Untold Stories, Beyond Methyl Bromide

January 17, 2018

“THE IDEA TO write this book came to me after I retired in 2005 and was cleaning out, re-reading, and reorganizing 40 years of files…in spite of three books and more than 200 journal publications and book chapters, my files filled with history and unpublished data were headed for the trash bin…the greater my urge to somehow pull the stories together into a single read-through description of my career…unique, it is the approach I took and the philosophy behind my approach to do hypothesis-driven research starting in the field, followed by the laboratory,” writes R. James Cook in the “Preface” to his book, Untold Stories (APS Press, 2017).

In 1974, Cook and Kenneth F. Baker co-authored a landmark book, Biological Control of Plant Pathogens. That book, which in some ways is a precursor to Untold Stories, summarized scientific evidence relevant to creating ecological balances favoring beneficial organisms (e.g. biocontrol agents, antagonists, competitors) as pesticide alternatives to control pathogens capable of weakening and destroying plants, including major food crops such as potato and wheat. Human medicine has at various times in various places employed a similar biological approach, such as using bacteriophages to fight diseases such as cholera, but for an array of reasons biological control has found more fertile ground in agriculture. Ecological balances can be tilted or nudged from pathogens to beneficial organisms in various ways, including via soil pH adjustments, tillage systems, cropping sequences, fallows, composts, amendments, nutrients, etc. The specifics can vary widely among crops, individual fields, regions, soil types, etc. Dr. Cook, as the Untold Stories subtitle, “Forty Years of Field Research on Root Diseases of Wheat,” hints, found wheat a fertile microcosm for exploring the phenomena of naturally disease suppressive soils for producing healthy crops.

Cook’s job when he joined the USDA Agricultural Research Service included soil diseases afflicting wheat, one of humanity’s most ancient crops and a worldwide dietary staple. The USA grew 45.7 million acres of wheat in 2017, most of it winter planted varieties, the lowest acreage since record keeping began in 1919. USA farmers grow twice as much corn and soybean, roughly 90 million acres of each. Wheat exports earn the USA roughly $6 billion a year, out of $140 billion in total agricultural exports. Though wheat helps the USA balance of trade, family farms growing wheat are not sustainable or economically viable if soil pesticides are used. Dr. Cook’s challenge was curing wheat soil diseases without costly pesticides. In the 1970s, the mainstream view was that solving pest problems without pesticides was drug-induced organic hippie crazy talk, a near impossible task with low probability of success.

Fortunately Dr. Cook possessed sound inner instincts complemented by scientific understanding of ecology and microbiology, with an emphasis on biological control of plant diseases absorbed working alongside Kenneth Baker and others at the University of California, Berkeley where biological control was still honored and respected despite falling from its early 20th century heights during the synthetic pesticide era. Cook briefly acknowledges Louis Pasteur, the famous French freelance microbiologist, chemist and entomologist who developed modern medical germ theory and laid the foundations for modern epidemiology while alleviating a mysterious silkworm colony collapse (disease epidemic) depressing the mid-19th century French economy.

On page 236 of Untold Stories, Cook quotes Pasteur: “In the field of observation, chance favors the prepared mind.” I would go back one step more to Pasteur’s mentor, chemist Jean Baptiste Dumas, who according to French-borne microbiologist René Dubos, persuaded a reluctant Pasteur to tackle the silkworm problem despite an insect ignorance for which he was widely ridiculed: “To Pasteur’s remark that he was totally unfamiliar with the subject, Dumas had replied one day: ‘So much the better! For ideas, you will have only those which shall come to you as a result of your observations!’” Microbiologist Alexander Fleming, famous for the fungal antibiotic penicillin, noted another important factor: “Louis Pasteur in his youth and throughout his life believed in hard work. He lived for his work and put his whole heart and soul into it. His was not a 40-hour week. He worked so constantly in his laboratory that it was inevitable that he became a beautiful technician…”

Another message embedded in Cook’s Untold Stories: Successfully tackle hard problems that appear insoluble to everyone else, and the probability of job security and life success increase. Cook developed an expertise in finding cooperative wheat farmers and locating fields where natural biological controls seemed to be working on their own. Then did a laboratory form of reverse ecological process engineering to find out why these fields developed a disease immunity or natural suppression of wheat soil pathogens. When you can replicate or duplicate the phenomena experimentally, then a degree of understanding can be claimed.

 

Untold Stories feels like the real nitty-gritty, with behind-the-scenes stories about how research projects are accomplished. The type of details typically omitted from science journals, by design. If anyone dared put into their journal article the details of how they obtained funding, navigated the bureaucracy to win support, or cleverly acquired a piece of new equipment, it would no doubt get edited out. This is a reason Roald Hoffmann in his book, The Philosophy, Art, and Science of Chemistry (Oxford University Press, 2012), suggested a new kind of science journal allowing first person “voice” and personal experience. Actually, it would only be “new” in the “retro” sense that “everything old is new again.” In the early days of modern science, personal autobiographical expression, musings and miscellany were common. These early science articles could be confusingly messy and hard to decipher, perhaps harking back to the deliberately obscure days of alchemy. However, personal observation and experience was handled well by agricultural researchers in the early 20th century. Which is not meant to denigrate the utility and immense value of standardized journal formats with introduction, methodology, results, discussion, etc. There is room in the world for both.

Untold Stories embeds science in a wider human context, beyond what is possible in the modern journal format, which necessarily excludes the human dimension, but leaves behind an unintended residue, a subjective impression of a science rendered lifeless by the invisibility of its practitioners. Cook family members pitched in to write the forward, edit, design and deliver their father’s book ready for printing by the American Phytopathological Society (APS) Press. Cook’s attitude towards public service is refreshing, and clearly extended into his so-called retirement. Judging from the 2005 start date and the 2017 book publication date, Dr. Cook put over a decade into this “Magnum Opus” book project. Wife and family were promised this would absolutely be his last book. One might lament, but I have to believe Dr. Cook mined his past experiences so thoroughly as to be able to rest on his laurels and not feel that much was left out that could not be remedied in a few journal articles.

A mathematical ratio of untold stories to published stories would be interesting, and Dr. Cook is in a position to be the expert. Let’s say the Untold Stories:Published Stories ratio was 1:1 and had a certain “volume.” Then the “volume” (e.g. measured in pages, articles/books, person-years of work, or whatever) of untold stories could be multiplied by the number of scientists or the amount published in a given time period to yield an estimate of how much scientific research ends up in the proverbial trash bin.

The Untold Stories photo caption on page 52 brought to mind a much maligned molecule, methyl bromide, a research tool and experimental control integral to scientific investigation of naturally disease suppressive wheat soils. Salt marsh microbes naturally produce methyl bromide as an antibiotic type weapon in waging ecological warfare for survival against competitors and antagonists. The caption: “A discussion session in progress at a Pacific Coast Research Conference on Soil Fungi with Professor S.D. Garrett, Cambridge University, as the discussion leader…Steve Wilhelm from UC Berkeley, credited with the introduction of soil fumigation to the California strawberry industry, is in the front row…”

Dr. Wilhelm, who I knew to also be interested in promising methyl bromide alternatives such as steam, marigold cover crops and green manures, crops up again on page 186 of Cook’s book: “it was not until the middle of the twentieth century that soil fumigation was used on a large scale…Steve Wilhelm at UC Berkeley…together with Albert Paulus at UC Riverside, did the pioneering work on the use of mixtures of chloropicrin and methyl bromide to control soil-borne pathogens and weeds before planting strawberries in California starting in the late 1950s. Strawberry yields were roughly 5 tons per acre in fields not fumigated and up to 25 tons per acre in fields that were fumigated.”

Soil fumigation with methyl bromide and chloropicrin worked so well that California had near zero untreated strawberry fields available to investigate for naturally suppressive soils, which is unfortunate, as methyl bromide use is being phased out under the Montreal Protocol as an ozone depleting substance. Something I learned about in more depth working with the late Jamie Liebman, a plant pathologist at BIRC (Bio-Integral Research Center), where as subcontractors we helped develop a Montreal Protocol methyl bromide alternative research agenda for funding by the U.S. EPA and United Nations. I wrote a short chapter on this period in history titled “Rowland’s Recipe for Climate Treaty Success” in an ABC-CLIO book titled Science and Political Controversy, edited by David E. Newton in 2014. In 2015, attending agricultural, soil and entomological science meetings in Minneapolis, not far from APS headquarters, I was pleased to find that research agenda still extant and going deeper. Funny what a mere photo caption can trigger in human memory. No doubt Untold Stories will have similar effects on readers whose interests and paths intersected with those of Dr. Cook.

California’s $2 billion strawberry industry, which produces about 90% of the USA crop, an awesome 1.7 billion pounds on about 40,000 acres (43,000 pounds of strawberries per acre), was for all practical purposes birthed into existence by injecting chloropicrin and methyl bromide into soils under plastic tarps. California’s hyper-productive strawberry growers, like Florida tomato and inland Pacific Northwest potato growers, can earn back methyl bromide soil fumigation costs. Family wheat farms would be bankrupted and abandoned to tumbleweed and erosion by soil fumigation costs. Scientifically, the less prosperous economics of wheat growing were fortuitous, as Dr. Cook was precluded from earning a living testing and recommending soil pesticides. Instead, as Dr. Cook’s book rigorously details, applied science became indistinguishable from pure science (much as it did for Pasteur) as it delved into the microbiology, ecology and non-chemical remedies for soil pathogens causing unhealthy plants and crop failures.

A key scientific discovery was that growing wheat in the same field again and again, year after year without interruption or rotation, can result in soils becoming naturally suppressive or functionally immune to disease pathogens. But this goes against centuries of accumulated wisdom arguing that toxic root secretions (allelopathy) poison the soil, and are best alleviated by crop rotations. Cook’s objection on page 227: “this makes no mention of a role for root diseases and ignores one of the most fundamental principles of plant pathology taught to beginning students in plant pathology, that growing the same crop in the same soil increases the populations of pathogens of the roots of that crop…It takes a long time to replace the first explanation with the correct explanation for almost any phenomenon in nature.” It also takes time, as those who have studied ecology know, for pathogen, prey or pest populations to build up to peaks before predator and natural enemy populations reduce or crash them down to low levels. Dr. Cook’s mission was to shorten that time.

One set of wheat experiments described in the “Take-All Decline” chapter 7, owed inspiration to 1950s’ potato scab disease research in Washington State, where small amounts (10%) of suppressive soil (presumably containing beneficial microbes) were added to disease-susceptible soils. Within 2-3 years, wheat soils were growing healthy plants. “Although I never repeated this experiment (nor did it need to be repeated), it would turn out to be the most influential experiment of my career,” wrote Dr. Cook on page 144. “It led to my award of a Guggenheim Fellowship…to my first competitive grant awarded by the USDA Competitive Grants Research Office (CARGO) in 1978…to the USDA ARS approving the formation of the Root Disease and Biological Control Research Unit in 1984; and to the USDA ARS providing permanent funds for me to hire…”

This only scratches the surface of a truly remarkable book likely to become a classic of science.


Natural Nicotine Heals Honey Bees

January 23, 2017

NEONICOTINOID INSECTICIDES (e.g. thiamethoxam, imidacloprid, clothianidin) developed at Bayer Japan as safer alternatives (e.g. to human spray applicators) to the natural nicotine once widely used by farmers and gardeners, is now suspected of contributing to honey bee health problems like learning disorders and colony collapse. In contrast, natural nicotine, found in honey produced by bees working tobacco fields, as well as in pollen, nectar, leaves and other plant parts, is a nutrient and medicine helping to heal weak honey bee colonies, said Susan Nicolson of South Africa’s University of Pretoria at “Entomology Without Borders,” a joint meeting of the International Congress of Entomology (ICE) and the Entomological Society of America (ESA) in Orlando, FL.

Natural nicotine, even if produced organically in a sustainable recycling sort of way from tobacco waste products, is mostly shunned in organic farming and gardening. “Over 120 million sites will be returned on a web search on tobacco, but most will not be associated with plant science,” wrote USDA-ARS researcher T.C. Tso in Tobacco Research and Its Relevance to Science, Medicine and Industry. “Many plant scientists in academic institutions cannot obtain grant support for projects using tobacco as a research tool. Some even have to avoid tobacco because of the applying of ‘political correctness’ to academic research. The tobacco plant has served as a valuable tool since the dawn of plant and biological sciences, so it is indeed a great loss to scientific progress that a research tool already invested with so many resources and about which there is such abundant knowledge and such great potential for new advancement is now being wasted.”

Honey bees readily consume bitter alkaloids such as nicotine mixed in sugary plant nectars. Adult honey bees excel at detoxifying alkaloids such as nicotine, which should not be surprising, as survival depends on it. Younger, larval honey bees have fewer enzymes to detoxify nicotine, but also survive quite well even when their royal jelly contains high levels of nicotine. Honey bees and insects immune to nicotine, such as green peach (peach-potato) aphids, transform nicotine into less toxic butanoic acid. A knotty question naturally arises: If natural nicotine heals honey bees, why are synthetic neonicotinoids so terribly different? Are natural compounds like nicotine inherently more beneficial and their synthetic analogs (e.g. neonicotinoids) inherently bad, perhaps due to subtle differences in molecular structure? If bees and other pollinators are a major concern, perhaps natural product restrictions on nicotine need to be relaxed to provide competition to the synthetic neonicotinoids.

“Alkaloids, especially in the nicotine family, have been the main focus of tobacco research because alkaloids are the characteristic product of tobacco,” writes Tso. Dozens of other tobacco molecules are relatively overlooked, including sugar compounds providing least-toxic botanical insect and mite control. Anabasine (neonicotine), an alkaloid found in tobacco and other plants, has also been widely used as a natural insecticide. Strangely enough, anabasine is also an insect attractant and a poison gland product of Aphaenogaster ants. In a strange urban twist to the wild bird practice of lining nests with medicinal herbs emitting essential oils counteracting parasites: Researchers in Mexico discovered urban birds lining nests with cigarette butts to similar advantage. In times past, organic gardeners soaked cigarette butts in water to get a nicotine spray brew. Historically, most commercial nicotine insecticide used on farms and gardens was a sustainable tobacco waste extract.

There are 60-80 described tobacco or Nicotiana species, some available in seed catalogs and grown as ornamentals. Most Nicotiana species grow wild in the Americas, with some in Australia and Africa. “Tobacco plants are easy to grow and have a short growing period,” writes Tso. “Each tobacco plant may produce 14 g or about 150,000 seeds which may provide seedlings for 2 to 5 acres (1–3 ha) of field tobacco, depending on the type.” In Europe, oil extracted from tobacco seeds is being explored for an alternative bio-diesel fuel industry, with dry leftovers as animal feed.

Native American Nicotiana species are being integrated into China’s ancient agricultural interplanting tradition. When tobacco is interplanted in vineyard rows, tobacco roots and grape roots intermingle. Perhaps some sort of biological soil fumigation occurs. Whatever the mechanism, vineyards are cleansed of soil-dwelling phylloxera aphids, a pest that almost destroyed wine grape growing in France in the 1800s and is still a worldwide problem. According to the journal Chinese Tobacco Science, intercropping tobacco with sweet potato also alleviates soil and other pest problems, maximizing profits per unit area of land. Burley tobacco is intercropped with cabbage and other vegetable crops, according to the Journal of Yangtze University (Natural Science Edition).

Neonicotinoids are soluble in water and absorbed systemically by plants, and some are sprayed on urban lawns and landscapes. However, over 80% of synthetic neonicotinoids are applied to seeds prior to planting hundreds of millions of acres of corn, soybean, sunflowers and other crops. In Canada’s Ontario and Quebec provinces, 100% of corn seed is treated with neonicotinoids, said Nadejda Tsvetkov of Toronto’s York University at “Entomology Without Borders.” Though neonicotinoids were seldom found in corn pollen samples, somehow, perhaps by water transport, neonicotinoids are finding their way into clover and willow tree pollen far from corn fields.

“For a lot of farmers it is hard to get seeds untreated, especially corn,” as commercial seed is routinely treated with neonicotinoids regardless of need, said the University of Maryland’s Aditi Dubey at “Entomology Without Borders. In Maryland and other mid-Atlantic USA states where low pest pressures are the norm, neonicotinoid seed treatments are both unneeded and counterproductive. In 3-year Maryland rotations with double-cropped soybeans, winter wheat and corn, sowing seeds treated with thiamethoxam or imidacloprid reduced beneficial predatory ground beetles and increased slug damage to crops. Mid-Atlantic USA farmers typically apply 4 unnecessary prophylactic seed treatments every 3 years. Besides reduced biocontrol and more pest damage, soil accumulation over time is a disturbing agro-ecosystem possibility.

Alternative seed treatments include natural plant hormones such as salicylic acid and methyl jasmonate, which induce a natural immunity called induced systemic acquired resistance (SAR). Crops such as lettuce and argula (rocket) grown from seed treated with salicylic acid and methyl jasmonate also release volatile gases repelling pests such as sweet potato whitefly, a major worldwide pest, said Ben-Gurion University’s Mengqi Zhang at “Entomology Without Borders,” a gathering of 6,682 delegates from 102 countries. Numerous botanical materials and microbes have also been investigated around the world as alternative seed treatments.

A proactive approach to honey bee and bumble bee health includes a diversified landscape sown with herbs and medicinal botanicals for self-medication, not just natural nicotine from tobacco nectar or other sources. Thymol, an essential oil found in thyme and many other plants, is already sprayed in hives by beekeepers to combat Varroa mites. At “Entomology Without Borders,” North Carolina State University’s Rebecca Irwin reported laboratory choice tests where bumble bees rejected nicotine. In field tests, bumble bees were given a choice of different colored flowers each with a different botanical such as thymol, nicotine, anabasine and caffeine. Bumble bees only selected flowers with thymol to self-medicate. Interestingly, thymol and other herbal essential oils also synergize nicotine, boosting effectiveness against disease pathogens and perhaps also minimizing the likelihood of colony collapse.

Landscapes and hedgerows sown with medicinal plants such as thyme, sunflower and foxglove minimize bumble bee disease transmission, said Lynn Adler of the University of Massachusetts, Amherst. The current USA farm bill will actually pay farmers to plant bee-friendly sunflower edges or hedgerows around canola fields. Antimicrobial and medicinal honeys derived from sunflower, bay laurel (Laurus nobilis), black locust, etc., also effectively combat bee diseases like chalkbrood and foulbrood, said Silvio Erler of Martin-Luther-Universität in Halle, Germany at “Entomology Without Borders.”

Bee pharmacology is also useful in human medicine. In Oaxaca, Mexico gangrene is stopped and wounds are healed by combining maggot therapy and honey, reported Alicia Munoz. Maggot therapy uses sterilized (germ-free) green bottle fly maggots to disinfect and cleanse wounds by eating unhealthy tissues and secreting antibiotics, allowing healthy pink tissue to grow back under honey-soaked gauze. This cost-effective approach reduces hospital stays, lowers morbidity and can eliminate the need for surgery. It may sound yucky, but for diabetics and patients with bed sores or wounds where surgery is medically impossible, a few maggots and a little honey is preferable to amputating wounded or infected limbs.

Cancer-fighting bee propolis products were touched upon at “Entomology Without Borders” by Chanpen Chanchao of Chulalongkorn University in Bangkok, Thailand, where hives of stingless bees are reared like conventional honey bees. Cardol, a major component of propolis from the Indonesian stingless bee, Trigona incisa, causes early cancer cell death by disrupting mitochondrial membranes and “producing intracellular reactive oxygen species (ROS).” ROS are essential to energy, immunity, detoxification, chemical signaling, fighting chronic and degenerative diseases, etc. Cardol “had a strong antiproliferative activity against SW620 colorectal adenocarcinoma,” killing colon cancer cells within 2 hours, followed by complete cell necrosis within 24 hours. Thus, cardol is an “alternative antiproliferative agent against colon cancer.”


Sunflower Power & Health

October 10, 2016

WITH PERHAPS 25 MILLION ha (62 million acres) of sunflowers grown for seed oil worldwide, sunflower diseases and pests and their remedies have a global impact. “Sunflower oil can be used as an alternative or additive to diesel fuel to create biodiesel, a clean-burning alternative fuel produced from a renewable resource,” wrote G.J. Seiler, one of many worldwide contributing authors to the Compendium of Sunflower Diseases and Pests, a book produced by the American Phytopathological Society (APS), a scientific group whose essence includes plant doctoring, discerning what makes for healthy versus diseased plants. “Use of the product may decrease farmers’ dependence on petroleum fuels by substituting ‘farm-grown’ fuel for use in diesel engines. For use in diesel engines, sunflower oil requires more extensive purification, including removal of waxes and gums. Minor engine modifications, such as improved fuel filters, are also necessary to burn any vegetable oil. Since the energy content of sunflower oil is less than that of diesel fuel, consumption is greater and power output is less.” However, the high-protein residues leftover from sunflower oil extraction have the right amino acid balance to mix with soybean meal to grow healthy chickens and livestock, a virtuous ecological cycling of sunflower plants.

Indeed, in Argentina’s southern Pampas, if you get the planting times right, sunflower and soybean are compatible as intercrops. Working in agriculture, I observed sunflower border rows or perimeters around conventional crop fields attracting pollinators and natural enemies providing biological control of pests. However, sunflowers are so attractive to beneficial insects that they do not want to leave. Thus, sunflower stalks need vigorous shaking to get green lacewings and natural enemies of aphids and other pests to take flight into adjacent crops needing protection. At the moment, fields of GMO canola producing high quality cooking oil are displacing sunflower fields in many areas. But the APS sunflower Compendium awakened my love for sunflowers, as even the diseases afflicting the plants have a certain beauty under the microscope. So, I can see the APS sunflower Compendium serving as an outstanding library reference for biology teachers and students looking for projects in sunflower-growing areas.

R.M. Harveson opens the APS sunflower Compendium with a brilliantly concise narrative chronicling the journey of sunflower seeds from their native North America to Russia, where innovative plant breeders painstakingly created the first modern sunflower seeds high in oils, providing the platform for today’s worldwide sunflower industry. The Mennonites, an anti-violence religious group migrating from Germany (Prussia) and a war-plagued Europe to Russia in the 1780s for free farm land promised by Catharine the Great, pioneered commercial sunflower oilseed farming in a harsh landscape long thought unsuitable for even subsistence farming. Their descendants were lured to Saskatchewan and Manitoba, Canada to create North America’s sunflower industry. During World War II, when “securing the fields of Ukraine was a major objective of Adolf Hitler’s war on Russia,” sunflower oil was a superior antifreeze, lubricating World War II weapons that froze with conventional gun oils. Joe Pappalardo’s excellent and entertaining book, Sunflowers: The Secret History: The Unauthorized Biography of the World’s Most Beloved Weed (Overlook Press) adds color and specifics, and is cited in Harveson’s “Selected References” in the APS Compendium.

Personally, I love the feel on my head and hair of a shampoo blending organic sunflower oil, citrus oils and herbs; and organic sunflower seeds at breakfast supply trace minerals like zinc, which is often deficient in produce grown in local California soils. Sunflower sap, which occasionally has been used medicinally, contains terpenoid compounds that show potential as alternative botanical pesticides. As ingredients in traditional medicines, wild sunflowers have been used for everything from wound healing and rattlesnake bites to combating infection and pain relief. Modern medical uses include topical oil formulations with sunflower oil to improve skin health, fight fungal infections, relieve inflammation and itchy, dry skin, and in dentistry to improve the gums.

Seed hulls of certain sunflower varieties are traditional sources of yellow, ruby red, purple, and black dyes or colorants (e.g. anthocyanins) useful in body painting, cosmetics, foods and textiles. Indeed, some plant breeders are working on a sunflower seed that would be high in oil and have a ruby red husk or hull that could be extracted to replace commercial synthetic red food dyes. Other researchers see the hulls as useful absorbents for wastewater reclamation. But by far, sunflower seed oils (e.g. NuSun for cooking) are the main sunflower item of commerce, and even trade on the commodities futures markets. Sunflowers seeds like Mammoth Russian for eating and snacking or adding to birdseed blends are important crops, but minor compared to the large acreages of sunflower oilseeds grown worldwide.

For various reasons, sunflowers have not become commercialized as a biotech GMO (Genetically Modified Organism) crop, which makes life easier for organic growers. Though perhaps better known from Van Gogh canvases, sunflowers were experimental subjects on the USA’s Apollo space missions. And “sunflowers have been successfully used as vehicles for the phyto-remediation of soil contaminated with heavy metals and radioactive materials (e.g. following the Chernobyl disaster),” wrote Harveson. In March 2011 after the Great East Japan Earthquake and Fukushima Daiichi Nuclear Power Plant accident, sunflowers and sunchokes were among the “alternative technology” plantings to concentrate and remove from soils radioactive cesium, which emits gamma rays and has a 30-year half life.

Sunchokes or Jerusalem artichokes, perennial sunflowers grown for edible tubers high in inulins, are sometimes recommended for diabetes and cardiovascular diseases, being associated with lowering blood sugar and cholesterol. Indeed, Jerusalem artichoke chips have been tested as a snack food alternative to potato chips for diabetics, being almost devoid of starch and fats. Several dozen other sunflower species are known, including one that is 92% pure natural rubber. Most likely sunchokes and other sunflower species including backyard ornamentals are subject to pests and diseases similar to those described in the APS Compendium.

To prevent pests and diseases, as a kind of insurance, perhaps 95% of commercial sunflower seeds are coated with neonicotinoid pesticides (e.g. thiamethoxam, clothianidin) at planting time, according to Michael Bredeson of South Dakota State University in Brookings at the 2015 joint meeting in Minneapolis of the Entomological Society of America (ESA), the American Society of Agronomy, the Crop Science Society of America, and the Soil Science Society of America. Bredeson studied 11 commercial sunflower fields, and found that “the seed treatment failed to improve yield or decrease herbivores.” In other words, quite apart from whatever effects on honey bees and beneficial organisms higher in the food chain, the neonicotinoid seed treatments are mostly a waste of resources and money. Though perhaps they do buy peace of mind for commercial sunflower growers, much like any insurance policy.

But the peace of mind bought by unnecessary early-season pesticide seed treatments may bring ecological food chain effects that cost sunflower growers more money and crop loss later in the season. The neonicotinoid pesticides may enter the food chain via plant nectar, plant tissues and predator consumption of tainted prey. Indeed, Pablo Gontijo and colleagues (2015) reported that sunflower seeds treated with thiamethoxam poisoned minute pirate bugs (Orius insidiosus), which are major predators of aphids, caterpillars, spider mites and other pests. Part of the problem is that the beneficial bugs, besides eating pests, also suck moisture directly from plants and thereby become poisoned by systemic pesticides used as sunflower seed treatments.

Likely the poisoned pirate bugs are only the tip of the proverbial iceberg. At the 2015 ESA meeting, Sirilak Lankaew from RYFCRC in Rayong, Thailand reported that cassava cuttings treated preventively with thiamethoxam provided 1-2 months cassava mealybug protection at the cost of food chain effects on beneficial insects via poisoned cassava nectar. Specifically the wasp Anagyrus lopezi, a cassava mealybug natural enemy, feed on the poisoned cassava nectar and “experience acute mortality for up to 21 days after treatment, and have significantly reduced lifespan for at least 42 days after treatment.” With 8 million farming households in Thailand growing cassava and 70% of Thailand’s small-scale farmers using neonicotinoid pesticides, there is a need for alternative technologies “fully compatible with (naturally-occurring and cost-free) biological control.” In sunflower, something like the APS Compendium to identify the potential problems is a good first step towards minimizing unnecessary pesticide treatments and developing alternative technologies.

One approach to developing sunflower soils that are disease-free and avoiding seed treatments is the opposite of crop rotation. Namely growing the crop repeatedly in the same soil so that disease organisms build up and then are destroyed by natural biological agents. It is like the predator and prey cycle, where pests buildup to high levels and even cause some damage before being opportunistically exploited and knocked down by their natural enemies. This approach, known as building a disease suppressive soil, can take a few years; and is perhaps best suited to patient organic growers with the wherewithal to weather those tough early years, and possessed of a confidence, hope or faith that the natural cycles will eventually play out. Likely the Mennonites whose experiences Joe Pappalardo recounts in his book took this route in turning the barren Ukraine, Russian and Canadian lands into productive agricultural fields in the era predating intensive chemical agriculture.

Another interesting alternative technology with ancient roots is interplanting, the idea of mixing different crops in the same fields. In Pakistan, sunflowers are being considered as a healthful alternative for local cooking oil shortages via interplanting sunflowers with the staple mungbean crop. In Florida, sunflower strips have been proven to attract honey bees and a variety of predators and parasitoids supplying natural biological pest control to adjacent organic vegetables. In China, parts of Asia and Africa, and even the Americas, sunflowers are viewed as an alternative technology to reduce herbicide use. Sunflowers provide natural weed control via shading the ground and natural herbicidal compounds (allelochemicals) toxic to some of the world’s worst weeds, such as dodder and barnyard grass. Multiple benefits if you can get rid of a weed patch, produce beneficial insects and pollinators, and harvest some seeds at the same time.

The health benefits of sunflowers will likely be a key driver for this crop in the future, though medicinal sunflower benefits are far from the cutting edge of agriculture and medical research in the genomic era. Broader medical applications may involve anti-inflammatory and cardiovascular benefits, bone health, detoxification, skin protection (e.g. from light & anti-aging) and anti-cancer effects. Applied to the skin, sunflower oil formulations may reduce bacterial and fungal infections, and are touted by some for premature newborns. In Cuba a product called Oleozon, sunflower oil treated with ozone gas, was registered in 1999 to treat fungal skin diseases (tinea pedis); and can stop bacteria and viruses resistant to multiple drugs.

Interestingly, researchers in Iran writing in the Journal of Food Science and Technology like the idea of infusing highly unsaturated oils like sunflower seed oil with raspberry or related Rubus species (e.g. blackberries) as a GRAS (Generally Recognized As Safe) alternative to preservatives like BHA and BHT. Rubus leaves add other medicinal properties to sunflower oil, “including as astringent, hypoglycemic, anti-diarrhea, anti-inflammatory agents for mucous membrane of oral cavity (mouth) and throat.” Many other oils and herbs may have medicinal value when combined with high linoleic acid sunflower oil. Time will tell.

The whole idea of plant medicines may yet return to modern medical practices for a variety of reasons. “Extended life expectancy is accompanied with an increase in age-related pathologies that include cardiovascular and neurological diseases, obesity, and cancer, conditions that are inflicting an immense pressure on health care costs and quality of life,” write researchers Andrea Doseff and Erich Grotewold at The Ohio State University and Arti Parihar in Ujjain, India, in the book, Pigments in Fruits and Vegetables (Springer, 2015). “Thus, there has been an increased interest in recognizing and understanding the mechanisms of action of active nutritional compounds with health benefits, or nutraceuticals, for the prevention and treatment of various diseases.”

The researchers in India and Ohio note that over 8,000 flavonoid chemicals beyond vitamins have been identified, including a range of anthocyanins like those in sunflowers, “which are responsible for providing colors to fruits and vegetables, and have dietary value as color additives with potential health benefits.” Over 10,000 tons per year of anthocyanins from black grapes alone are consumed every year, and this whole general category of plant pigment compounds has “uses in the prevention and treatment of inflammatory diseases including cardiovascular diseases, obesity, and cancers.” Who knows what concentrated research into sunflowers would reveal?


Pigments of the Imagination: Cochineal’s Renaissance

June 22, 2016

SAP-SUCKING SCALE INSECTS, such as cochineal, kermes and lac, are sometimes sprayed with pesticides as landscape and crop pests, and other times cultivated as beneficial insects. For example, cochineal secals have provided biological weed control in India, Australia and South Africa where imported prickly pear cactus (Opuntia spp.) hedges have escaped and become rangeland weeds. Cochineal scale insects, bred in ancient Mexico to yield 15%-30% color pigment content, have been grown in the Americas for many centuries on prickly pear cactus as a sustainable, biodegradable colorant crop yielding dyes ranging from red, yellow, orange and brown to pink, lavender and purple (depending on mordant, pH, etc.). Intensely red cochineal has a long and famous history in painter’s palettes, tapestry and fabrics, and has been used for centuries to color or stain tissues red or purple for microscope visibility in biology and microbiology labs, medicine and dentistry. Cochineal scale pigments also color selected beverages, foods (on labels as E-120 & carmine) and cosmetics like lipstick, rouge and nail polish. Biochemistry labs like the cochineal red molecule’s ability to bind or bond with proteins, nucleic acids and fats (lipids). Analytic chemists use cochineal “for photometric determination of boron, beryllium, uranium, thorium, and osmium.” At the cutting edge frontier of science, cochineal pigments are being adapted to “molecular information processing” and computing. The red pigment’s “strong photosensitization and photocurrent switching effects” are being designed into next generation optoelectronic (i.e. light, photon) devices like semiconductors, fuel cells, sensors and photovoltaic solar energy systems.

“In Latin-the indispensable language of Renaissance medical professionals—the word pigmentum signified both a pigment and a drug,” writes Amy Butler Greenfield on page 83 of the paperback edition of her meticulously researched book, A Perfect Red, which follows the parallel rise and fall of the Spanish Empire and the secretive cochineal red export trade. “Artists who made their own paints were often advised to procure cochineal from their local “Drugist” or pharmacy, advice that highlights the fact that Europeans also used cochineal as a medicine,” a practice “at least partly borrowed from ancient Mexico,” where cochineal was used to clean teeth and also dissolved in vinegar and applied as a poultice to cure wounds and strengthen bodily organs. Spain profited more from importing cochineal into Europe than from all its plundered and mined New World gold. When ancient alchemy’s metamorphosis into modern chemistry advanced to synthesizing a less expensive, wider range of brighter dye pigments, the Spanish red dye monopoly was obsoleted and the financial collapse of the steadily weakening empire allowed for a global power shift; the USA, fresh from coast to coast expansion and hot for global colonial-style conquests, easily knocked off the remnant hollow shell of the Spanish Armada in the Caribbean and Philippines in 1898.

Let’s start with cochineal and scale insects as pests, and organic control alternatives, as that is how most people encounter and view scale insects. Parasitoid wasps, lady beetles, birds and many other natural enemies provide biological control of scale insects, but not always enough at the right time. Highly refined petroleum oils, vegetable oils and high-pressure water sprays (with or without soap or surfactants) are among the often used remedies. High pressure water sprays, from a nozzle or heavy overhead rainfall, wash off or injure cochineal scales; and this remedy is sometimes used post-harvest by packing houses to clean fruit prior to shipping. Laboratory studies indicate that epazote (Chenopodium ambrosioides), mint (Mentha spp.) and marigold (Tagetes spp.) extracts applied with emulsifiers are potential organic or environmentally friendly synthetic pesticide alternatives.

At the Entomological Society of America (ESA) annual meeting in Minneapolis I talked with Colorado State University extension entomologist Whitney Cranshaw, whose special spiked shoes for killing white grub beetle larvae beneath the soil surface while walking golf course turf and lawns achieved notoriety in Smithsonian magazine many moons ago. This time he was a lonely entomologist, as out of hundreds of passersby no one was stopping at the poster of graduate student Rachael Sitz reporting on a kermes scale vectoring a bacteria causing drippy blight of red oaks in Colorado. Cranshaw was ecstatic having a customer, and figured I was studying the poster display because the kermes scale was also found in California locales such as San Jose, Mammoth Lakes and Monticello Dam on blue oaks and chinquapin bushes. Actually, I was wondering if this particular kermes scale, which went by the scientific name Allokermes rattani, was related to Old World kermes scales used for centuries by pigment artists in Europe and Asia. According to Cranshaw, workers handling the Colorado kermes scale came away with hands dyed a deep brown. So, perhaps this “pest” scale insect is indeed an untapped resource, similar to cochineal, waiting to be discovered by textile artists, painters and photographers looking for natural organic pigments.

My own interest in these insect pigments is a bit abstract, how to incorporate these pigments into the photographic printing process, inspired in part by viewing Robert Rauschenberg’s vegetable pigment prints with photo images from Indonesia. Cochineal was apparently on occasion used in early color photography printing, dating back to the 1800s and heliochromes, which I surmise are solar prints that also use silver as a light-sensitive pigment. Some modern authors talk of a “green synthesis,” fusing conventional silver nanoparticle photography with cochineal red pigments; but I have not found much on the subject. “Color photography,” U.S. Patent No. 923,019 from 25 May 1909 reads: “To all whom it may concern: Be it known that I, EDGAR CLIFTON, a subject of His Majesty the King of the United Kingdom of Great Britain and Ireland, residing at 3 BeaufortVillas, London Road, Enfield, in the county of Middlesex, England, have invented certain new and useful Improvements in Color Photography…known as the two color process; the three color process; and the four plate process…so that the assemblage gives more or less natural color effects…As the red dye: alizarin (with alumed reliefs), cochineal red (or carmin with ammonia), or magdala red…”

SCALING UP PRODUCTION of pigment scales, versus natural harvest, is often surprisingly difficult. For one thing, about 14,000 individual scale insects are needed to obtain 100 grams of raw cochineal pigment. Far from being dumb savages, ancient Mexico’s New World cochineal growers were superb insect breeders. The best cochineal “breeds” contain 18%-30% pigment by dry weight. Spaniards settling in the New World never mastered the delicate art of cultivating cochineal scale on prickly pear cactus, and instead relied on the indigenous los indios de Mexico, some of whom grew rich on the cochineal trade in what was essentially a free market. Many Spanish colonists found it intolerable that the natives were becoming the richest citizens, and this led to all kinds of frictions and conflicts aimed at turning the natives into poorer, more docile (less uppity) and easier to control colonial subjects. The Spanish were remarkably successful at keeping curious outsiders out of the cochineal production areas for centuries, making the cochineal red dye one of the world’s all-time best kept trade secrets. Most Europeans assumed the grana or granules of cochineal were seeds or plant material, like indigo or madder. On those rare occasions when the secret was revealed, the public refused to believe that cochineal red was literally dried insects. This combination of secrecy and worldwide ignorance allowed the Spanish cochineal monopoly to persist for several centuries and be more lucrative than precious metals.

As any entomology grad student can tell you, the same insect that is an abundant pest can often be impossibly hard to grow when you want it for experiments or as a thesis subject. For one thing, the “insect crop” usually has its own set of pests (called natural enemies), which for cochineal scales includes bacteria, lady beetles, syrphid or hover flies, predatory caterpillars, rodents, reptiles and birds. To prevent “crop failure,” cochineal scales need pampering and protection: 1) from natural enemies; 2) shade to protect from direct sunlight; 3) shelter from heavy rains that wash off and injure the scales. Raising cochineal scales as “farm animals” or “livestock” on prickly pear cactus was often a family enterprise in Old Mexico, an art or skill passed down from generation to generation. The prickly pear cactus itself is still also food, animal fodder and medicine in Mexico. But cochineal grana are no longer treated like money or currency, as it was in Aztec Mexico when cochineal was used in payment of tribute or taxes. In that sense, in contrast to a modern dollar, euro, yen, peso, pound, rupee or digital currency, which cannot be directly used as dyes or medicines, the grana possessed an exquisite versatility and flexibility in ancient times.

CARMINIC ACID, a MEDICINAL CHEMICAL pigment compound extracted from cochineal and first synthesized in 1998, belongs to a class of anti-tumor and antibiotic compounds called anthracycline derivatives, which “are believed to develop their cytotoxic effect by penetrating into the tumor cell nucleus and interacting there with DNA,” write chemists at Gazi University in Ankara, Turkey. Combined with other compounds, cochineal is also active against viruses and other microbes. In Tamil Nadu, India cochineal scale insects collected from cacti are crushed, boiled in water and dried to a powder used against whooping cough and as a sedative. Other traditional uses likely abound.

In nature, cochineal functions as an insect repellent. One theory is that cochineal repels ants, protecting young scale insects before their protective waxy outer covering forms. A carnivorous caterpillar eating the scales incorporates the cochineal dye into its own bodily defenses. A study in the Journal of Polymer Science concluded that cochineal and other natural dyes (madder, walnut, chestnut, fustic, logwood) and mordants (aluminum, chrome, copper, iron, and tin) increased the insect resistance of the wool fabric to attack by black carpet beetles.” Indigo was least effective, and cochineal and madder were most effective except when used with tin and chrome as the mordant or binding agent. I only remember one ESA presentation investigating cochineal as a natural insecticide, and that was back in 2004; the idea was that since carminic acid was already approved as safe for food by the FDA, cochineal could be formulated as an organic bait spray to stop fruit flies without losing organic certification. The researcher theorized that cochineal needs sunlight to be activated as an insecticide, and would thus be ideal for organic agriculture. But as far as I know, the idea was never adapted as an agricultural or quarantine practice.

COMBINING COLOR and HEALING is, however, an idea gaining traction. Carminic acid, a brilliant red compound constituting about 10% of cochineal8, “is one of the most light and heat stable of all the colorants and is more stable than many synthetic food colors,” write Khadijah Kashkar and Heba Mansour in the Department of Fashion Design at King Abdul Aziz University, Saudi Arabia. “Besides the color attributes, recently, also has been reported to beneficial to health with potential antibiotic and antitumor properties. At the beginning of the 21st century it is predicted that many colors will be used for both their additional beneficial functions in the body, as well as, coloring effect.” Whether color and healing were also linked in ancient or Aztec times with cochineal is an intriguing question. Perhaps everything old is indeed new again, but who knows what the ancient New World healers or shaman thought when applying bright red or purple cochineal poultices.

PREVENTIVE MEDICINE might be what to call the combination of organic cotton and natural cochineal dyes to block ultraviolet light from skin contact. Ajoy Sarkar of Colorado State University, writing in the journal BMC dermatology: “The ultraviolet radiation (UVR) band consists of three regions: UV-A (320 to 400 nm), UV-B (290 to 320 nm), and UV-C (200 to 290 nm). UV-C is totally absorbed by the atmosphere and does not reach the earth. UV-A causes little visible reaction on the skin but has been shown to decrease the immunological response of skin cells. UV-B is most responsible for the development of skin cancers…Other than drastically reducing exposure to the sun, the most frequently recommended form of UV protection is the use of sunscreens, hats, and proper selection of clothing. Unfortunately, one cannot hold up a textile material to sunlight and determine how susceptible a textile is to UV rays.” Heavy concentrations of synthetic dyes in synthetic fabrics generally provide good UVR protection, but are not as comfortable as cotton fabrics for warm, humid climates. Generally, the darker the color and the thicker the weave or denser the fabric, the better to protect against UVR. Depending upon the weave (e.g. twill vs sateen), Sarkar reported good to excellent UVR protection with natural dyes such as madder, indigo and cochineal.

COCHINEAL’S 21ST CENTURY RENAISSANCE and resurgence includes harnessing cochineal’s ability to capture (harvest) or route light (photons) and electrons in advanced or next generation optoelectronic devices such as semiconductors, light harvesting antennae, sensors, fuel and solar cells, and molecular information and logic gates for computing devices. I was surprised to learn that natural pigments have a long history in advanced electronics: “As early as the birth stage of lasers, coumarin, which is found naturally in high concentration in the tonka bean (Dipteryx odorata), was used in dye lasers” and “coumarin dye is still the basic active medium for many tunable dye laser sources,” writes M. Maaza (2014) of the University of South Africa. “Extracts from Hibiscus sabdariffa, commonly known as Roselle, carminic acid of the cochineal scale and saffron exhibit exceptional nonlinear optical (NLO) properties of a prime importance in optics.”

THE “NEXT GENERATION” SOLAR CELL replacement for today’s silicon-based solar cells will probably be a dye-sensitized solar cell (DSSC) based on titanium dioxide (TiO2), a semiconductor material that is fused with color pigments analogous to those used in conventional color photography (e.g. silver halide emulsions sensitized by dyes). TiO2 and other metal oxides are widely used in medicine, food preservation, cosmetics, sunscreens, paints, inks and a wide range of electronic devices for sensing, imaging, optics, etc. TiO2 is relatively inexpensive, and deemed low toxicity. Interestingly, TiO2 nanoparticles for solar cells can be produced from cultures of bacterial cells, such as the Lactobacillus sp. found in yogurt or curd, which means an even “greener” solar cell fabrication process.

The scientific roots of the modern solar cell go back to French physicist Edmond Becquel’s discovery of the photovoltaic effect in 1839; and prototype solar cells with efficiencies of 1% or less also date back to the 1800s. Though Albert Einstein explained the photovoltaic effect in 1904, the development of lightweight solar energy cells to power spacecraft in the 1950s. But the DSSC or Grätzel cell is a 1990s’ innovation attributed to Mr. O’Regan and Michael Grätzel. “This new device was based on the use of semiconductor films consisting of nanometer-sized TiO2 particles, together with newly developed charge-transfer dyes,” and had “an astonishing efficiency of more than 7%,” write Agnes Mbonyiryivuze et al. (2015) in the journal Physics and Materials Chemistry.

Next generation DSSCs or photovoltaic cells are currently undergoing a major design transition using natural color pigments like those found in cochineal scale insects. DSSCs with efficiencies in the 10% to 15% range can be manufactured with titanium dioxide (TiO2) nanoparticles bonded on a thin film with a light-sensitive dye utilizing a rare and expensive platinum group heavy metal, ruthenium (Ru; named after Russia). Ruthenium’s relatively high cost and environmental and toxicology concerns are a barrier to commercialization that is spurring the search for substitutes; namely cheaper and more environmentally friendly natural pigment. Companies working “to bring DSSC technology ‘from the lab to the fab’” include “Dyesol, G24i, Sony, Sharp, and Toyota, among others,” write Mbonyiryivuze et al. (2015). “Functional cells sensitized with berry juice can be assembled by children within fifteen minutes, the large choice of colors, the option of transparency and mechanical flexibility, and the parallels to natural photosynthesis all contribute to the widespread fascination. In 2013, the drastic improvement in the performance of DSSC has been made by Professor Michael Grätzel and co-workers at the Swiss Federal Institute of Technology (EPFL). They have developed a state solid version of DSSC called perovskite-sensitized solar cells that is fabricated by a sequential deposition leading to the high performance of the DSSC. This deposition raised their efficiency up to a record 15% without sacrificing stability…this will open a new era…even surpass today’s best thin-film photovoltaic devices.”

“PIGMENTS MAKE NATURE COLORFUL and LIKABLE,” writes Chunxian Chen, a researcher at the University of Florida’s Citrus Research and Education Center and the editor of a 277-page book published by Springer in 2015, Pigments in Fruits and Vegetables: Genomics and Dietetics, which places a heavy emphasis on the nutritional and medicinal benefits of colorful natural pigments like those coloring crops of carrots and sweet potatoes orange and radishes and tomatoes red. “Plant pigments usually refer to four major well-known classes: chlorophylls, carotenoids, flavonoids, and betalains…Chlorophylls are the primary green pigments for photosynthesis. The latter three are complementary nongreen pigments with diverse functions…The importance of colors in living organisms cannot be overstated…they are biosynthesized behind the scenes in living organisms and ultimately ingested in daily diet.” Presumably this daily consumption and medicinal benefits makes natural pigments in general logical and sustainable alternatives to expensive heavy metals in “green” electronic, computer and solar energy cell designs.

Agnes Mbonyiryivuze, in her 2014 dissertation titled “Indigenous natural dyes for Gratzel solar cells: sepia melanin,” provides a readable overview of solar energy cells utilizing natural pigments. The list of natural pigments fabricated into solar cells is long, and the sources range from cochineal scale insects, green algae, baker’s yeast, fungi and bacteria to bougainvillea flowers, Chinese medicinal plants (e.g. tea, pomegranate leaves, wormwood, mulberry fruit) and food crops like beets, parsnip, purple cabbage, blackberry and black grapes. The black pigments are of particular interest, including skin melanins providing UV protection and the black powder from cuttlefish (Sepia officinalis) ink sacks. “To maximize the absorption of more photons from the sun light for DSSC,” writes Mbonyiryivuze, “it is better to have a black dye sensitizer having extremely high broadband absorption. It should absorb not only in visible range but also in ultraviolet and near-infrared regions. This challenge can be handled by using natural dyes from other sources such as fauna from which sepia melanin was obtained. Melanins are well-known natural pigments used for the photoprotective role as a skin protector because of their strong UV absorbance and antioxidant properties. Melanin possesses a broad band absorbance in UV and visible range up to infrared.” Sepia melanin “can also conduct electricity and is thus considered a semiconductor material.”

“There are numerous trials of solar cell construction which are based on biomolecules and supramolecular systems, for instance, chlorophylls, porphyrins, phtalocyanines, and other natural or bioinspired dyes,” write researchers in Poland constructing double layer solar cells with cochineal red and gardenia yellow pigments bonded to TiO2 nano-surfaces. “Hybrid materials incorporating biomolecules immobilized on conducting or semiconducting surfaces are unique systems combining collective properties of solids with structural diversity of molecules, which besides photosensitization show other unique electrochemical and catalytical properties.”

According to Mousavi-Kamazani et al. in Material Letters (2015), quantum dots composed of cochineal and copper offer the economically attractive “possibility of single step production of three-layered solar cells.” Clearly, though the distance might be measured in years or decades, we are getting closer to a cochineal and natural pigment renaissance that transcends traditional fabric dyes and artist’s pigments and extends into medicine and the heart of modern computers, lasers and electronic and optical devices of all sorts.


Insect Perceptions, Irrelevant or Important

February 23, 2016

“IT WAS THE BUTTERFLIES, my people say, who brought the first human babies to their feet,” writes Canadian Richard Wagamese in “Butterflies Teachings,” an essay touching on “what’s called Enendamowin, or Ojibway worldview” in his brilliant collection, One Native Life. “Before that, the New Ones sat in innocence beneath a tree, watching the world around them with wonder. But Creator had planned more for them. Their destiny called for them to move throughout the world. These human babies were meant to walk upon their two legs, and as long as they sat under that tree their destiny could not be fulfilled…The air seemed to tremble with butterflies. The human babies were entranced. Each time they tried to snare a handful of colour, the cloud drifted away. They stretched their arms higher. They thrust out their hands. But it was to no avail. When the butterflies danced just out of reach a final time, the New Ones lurched to their feet and raced after them across the meadow. The Animal People celebrated quietly, then returned to their dens and burrows and nests. The human babies never caught those butterflies, but they kept on running, right into the face of their destiny…”

Quite a different worldview from Prague and Eastern Europe, where Franz Kafka’s famous novel Metamorphosis begins: “As Gregor Samsa awoke one morning from uneasy dreams he found himself transformed in his bed into a gigantic insect.” According to the “wall notes” in the exhibit “Disguise: Masks & Global African Art” at the Fowler Museum at UCLA, Kafka’s words inspired South Africa artist Walter Oltmann. Among neon masks, dancing mask videos and sculptured African animals wearing masks are Oltmann’s large anodized aluminum and brass wire caterpillars in the midst of “transformation and change” (metamorphosis) and fashion sketches titled “Beetles & Suits.” The suit coats are gracefully curving, shell-like beetle elytra (outer wing covers) fashionably topped off with the latest antennae, and looking both business-like and sci-fi out of Star Wars or Star Trek at the same time. I can easily imagine a cell phone age makeover of The Beatles’ Sgt. Pepper’s Lonely Hearts Club Band regalia and long hair with “beetle suits” and high-fashion antennae. Perhaps too much entomology affects the psyche. Oltmann writes that “spending an inordinate amount of time on making something that is usually considered insignificant like an insect, does make us look differently at them.” He says it “speaks of neither this nor that,” but I’m not so sure.

Insect observations appear in haiku by Japanese master Matsuo Basho, whom I think of as the late 1600s slightly more refined counterpart of 20th century Los Angeles poet Charles Bukowski, who was too busy with “other interests” to notice beetles, flies, mosquitoes and roadside weeds. In Moon Woke Me Up Nine Times: Selected Haiku of Basho, translator David Young writes: “Odd numbers predominate; a dance is occurring, and each third of the poem is a turn, a gesture, a refining or revelation… The poem seems to end almost as soon as it has begun, a small flash of lightning…A more literal version of the haiku cited (below) would be something like: What can save your life? / one leaf, with an insect / sleeping on its journey… the journey, which refers to a Chinese story that Basho’s readers would know but that is largely meaningless to English readers…‘Basho mash-ups,’ I have sometimes called my versions”:

One insect
asleep on a leaf
can save your life

Perhaps Basho was thinking of medicinal silkworms slumbering on mulberry leaves, or perhaps his mind was journeying among high mountains where ghost moths metamorphose with fungi into plant-animal hybrids that have been used in Asian medicine for centuries. David Young says about haiku: “They love to startle, first the writer and then the reader. As though a hummingbird were to land suddenly on your resting arm. It is the way the world so often surprises us.”

A haiku by Los Angeleno Mark Jun Poulos, whose observation of the seemingly mundane urban habitat nagged at me long after I thought I had dismissed its ordinary elements from consciousness:

restroom sink-—
ladybug cooling off
in a drop of water

What nagged at me was water, a vital ingredient of life, which as hard sprays of rain washes away pesky mites and aphids that are ladybug prey. Water (H2O) is also a missing ingredient in most ecological studies of interplanting, a habitat diversity strategy designed to boost populations of lady beetles and other beneficial insects providing natural pest control. Australian grape vineyards and California lettuce fields have had some success interplanting blooming rows of sweet alyssum to provide pollen, nectar and alternative prey for ladybugs, lacewings, hover flies and other beneficial species consuming aphids and other pests. Sweet alyssum is also host to micro-wasps helping Michigan asparagus growers by parasitizing leafmining pest insects, Amanda Buchanan of Michigan State University reported at the Entomological Society of America (ESA) annual meeting in Minneapolis. But if habitats are missing water, then perhaps lady beetles, which do not puncture plants to drink fluid, will leave to find restroom sinks, puddles or other water sources. Perhaps, like providing water bowls for pets, something similar needs to be researched as part of biological control habitat alternatives. Though I would draw the line at alcoholic drinks, except perhaps beer in snail and slug traps. Another urban haiku observation by Mark Jun Poulos:

sultry afternoon—
wasp hovers over a whiskey bottle
held by a drunk bum

Ethanol or ethyl alcohol, by percentage the main chemical component of distilled whiskey, should not be abused, nor perhaps should it be so heavily subsidized as a biofuel, as that incentive exacerbates huge landscape changes measurable as reduced biodiversity. At Synergies in Science, a rare Minneapolis gathering of the ESA, American Society of Agronomy, Crop Science Society of America and Soil Science Society of America, the diminishing biodiversity of a Midwest USA with 21% less wheat, 16% less hay and much more GMO corn to distill into ethanol motor fuels was as hard to ignore as a drunk with a whiskey bottle on an urban bench. Jonathan Lundgren of the USDA-ARS in Brookings, South Dakota said we need to get away from our “very pest-centric approach” and adopt a more holistic biological network approach. Instead of a Midwest saturated with pesticides to grow GMO corn to distill into fuel tank ethanol, something as seemingly simple as adding biodiversity via cover crops amongst the corn rows could produce enough soil biocontrol of corn rootworm to eliminate wasteful neonicotinoid seed treatments whose honey bee and beneficial insect friendliness is being hotly debated. Karen Friley of Kentucky State University reported at the ESA that something as seemingly simple as native plant border rows around sweet corn fields “provide microclimates in the form of moderated temperatures, which offer shelter” for numerous natural enemies controlling corn pests.

Curiously enough, ethanol (alcohol) like that in whiskey bottles and vehicle fuels also attracts pine beetles and ambrosia beetles considered destructive forest, landscape, street tree and nursery pests. Perhaps more curiously, the very trees being attacked are producing the ethanol and releasing it into the atmosphere when stressed (e.g. by drought or flood), decaying or dying. Trees may look perfectly healthy on the outside, but inside the tree is another story, because ethanol emissions are signs of sickliness and ill health. Chemical ecologist Christopher Ranger of the USDA-ARS in Wooster, Ohio said it is a real problem, for example, when nursery seedlings are used to replant spruce forests or with dogwoods, magnolias, pines, etc. in nurseries, backyards, along streets, etc. It is definitely ecology, as the ethanol is luring in the beetles to help “recycle” the trees back into the soil as nutrients.

I liked Ranger’s reasoning: Find the tree equivalent of driver breathalyzer tests as a beetle-attack early warning system. SCRAM wrist bracelets worn by offenders for transdermal drug and alcohol detection were tested, but were not sensitive enough; taking a week to detect low tree ethanol exhalations, whereas beetles detect a few parts per million of alcohol and get to trees almost on day one. The solution was a portable ethanol monitoring device with a detector tube and a plunger to pull in air samples; developed using Japan’s Gas Tech industrial gas leak detection technology for quick detection of “inebriated” trees.

So, which is more startling and surprising: art, haiku or entomology?

Strange brew: September 17, 2015 daylight turning to dark, caught in one of those infamous, almost proverbial L.A. traffic jams at a freeway underpass on Church Lane transitioning from Sunset Blvd to Sepulveda Pass on my way past the Getty Museum to Mulholland Drive, listening to the Moody Blues Live at Red Rocks, going nowhere. Haiku and fireflies flashing internally, and externally the blinking side turn lites and red back brake lights suddenly and surprisingly metmorphosed into synchronous fireflies, albeit of a mechanical or robotic nature:

Tail and Turn Lights
Flashing like Synchronous Fireflies
In the Los Angeles Traffic Jam

 


Cholera Biocontrol (vaccines & antibiotics are insufficient)

October 22, 2015

CHOLERA, a VIRULENT, SOMETIMES lethal version of Montezuma’s Revenge, the diarrheal gut scourge bane of travelers, is commonly associated with pesky Vibrio bacteria; though similar symptoms are associated with the sometimes disease-causing and sometimes beneficial E. coli gut bacterium and many other intestinal tract microbes. Cholera is commonly controlled by an integrated management approach, often including proper sewage sanitation, water filtration, antibiotics, vaccines, rehydration therapy and the fortuitous presence of natural enemies known as phages.

Phages, short for bacteriophages, are ‘bacteria-eating’ viruses; the name phage is from the Greek word ‘phagein’, which means ‘to eat’. One might think of cholera as being like the black plague, a no longer relevant disease of the past. But a recent Google News search indicates lethal cholera outbreaks worldwide: From 54 dead in one month in Dar es Salaam, Tanzania, to Rwanda and Nigeria in Africa to Iraq in the Middle East and Haiti in the Americas; with worries about outbreaks in refugee camps worldwide where wars rage and after natural disasters such as earthquakes destroy sanitary infrastructure. In Iraq, “The epidemic is concentrated in the town of Abu Ghraib, situated about 25 kilometers (15 miles) west of the capital, Baghdad, where cholera has claimed at least 10 lives,” according to Iran’s Press TV. “Health Ministry spokesman Rifaq al-Araji has blamed the cholera epidemic in Iraq on low water levels in the Euphrates, noting that simmering temperatures during summer months may have activated the bacterium that causes the deadly disease…Cholera is an acute intestinal infection caused by ingestion of food or water contaminated with the bacterium Vibrio cholerae. It is a fast-developing infection that causes diarrhea, which can quickly lead to severe dehydration and death if treatment is not promptly provided.”

According to a “Major Article” in THE JOURNAL OF INFECTIOUS DISEASES: “Vibrio cholerae serogroup O1 and O139 organisms cause acute, watery diarrhea, with an estimated 100, 000–150, 000 deaths annually…Despite global efforts to improve drinking water quality and sanitation in developing countries, there has been little evidence of a decline in the global burden of cholera in recent years. Interest has therefore increased in the use of cholera vaccines as adjuncts to other preventive and therapeutic measures…Live oral cholera vaccines have the theoretical advantage of simulating infection by natural cholera. Experimental infection of North American volunteers has been shown to protect against cholera upon rechallenge…However, to date no live oral vaccine has conferred protection to cholera-endemic populations when tested in a randomized trial, suggesting that the predictions from studies of volunteers lacking preexisting immunity to cholera may not be readily generalizable to cholera-endemic populations.”

According to the United Nations News Centre: “A global stockpile of vaccines, funded by a number of international organizations and foundations, initially made 2 million doses of the vaccine available. In 2015, with additional funding from the GAVI Alliance, the number of doses available for use in both endemic hotspots and emergency situations is expected to rise to around 3 million. There are several examples in which the vaccine has stopped cholera outbreaks in their tracks, such as in South Sudan in 2014…But new outbreaks are ongoing in South Sudan and Tanzania” in 2015, indicating vaccines to produce natural immunity in conjunction with the best that can be done in the way of sanitation and clean water supplies is not enough. Using phages to produce natural biological control of the cholera bacterium, as part of a low-cost, integrated pest management approach, seems to have been totally and completely neglected, almost as if the successes of natural biocontrol of disease bacteria with phages from the years 1917 into the 1930s and continuing into the present in some parts of the world have been totally purged from the Western medical and public health history books. A costly neglect, in terms of human lives.

“Cholera generated as much horror and revulsion among Europeans as bubonic plague had before it, in part because of the blue-black shriveled appearance of its victims and in part because it could strike anyone without warning and kill in 4 to 6 hours,” according to an overview in Microbiological Reviews which implicated “sailors and colonists” in cholera’s global spread, not just poor sanitation (mixing sewage into drinking water supplies). “Although cholera is treatable with antibiotics and oral rehydration therapy (fluid and electrolyte replacement), it is nevertheless an extremely debilitating and sometimes fatal disease. The severe dehydration and cramps symptomatic of the disease are a consequence of the rapid, extreme loss of fluid and electrolytes during the course of the infection. The diarrhea is caused by the action of cholera toxin (CT), secreted by the bacterium Vibrio cholerae, although in some cases it may be caused by the related Escherichia coli heat-labile enterotoxin (LT).”

Historically, as mentioned in a previous blog post titled “Compost for Sustainable Soil Fertility & Disease Suppression,” Japanese cities adopted a more sustainable approach and thereby escaped the cholera epidemics afflicting London, Paris, India, the rest of Asia and the Americas: “Human waste, euphemistically called night soil, became a valuable soil fertility commodity in old Japan. Perhaps not quite worth its weight in gold, but a valuable commodity bought, sold, traded, and transported long distances from cities to farms. Rather than causing cholera and other diseases by entering the water supply as was common in European cities of the same era, sanitation and composting blessed Japan with multiple dividends…Farmers in old Japan spent their own money to build toilets and urinals along well-traveled roads for public use…” No doubt phages were also part of the integrated mix of methods providing natural biological control of cholera in old Japan, even if the invisibly small phages went unrecognized.

The 20th century use of phages for biological control of cholera and other disease bacteria was pioneered by the self-taught, French-Canadian microbiologist Felix d’Herelle, whose phage work was said by many to also be the foundation for modern molecular biology. An itinerant or journeyman scientist, who spent his life much like the modern-day post-doc, migrating from job to job around the world as he promoted phage therapy, d’Herelle was working with the Pasteur Institute in Paris while French and German troops were lining up against each other on the Western Front in World War I. In North Africa, as early as 1910, d’Herelle was pioneering the use of microbes to control biblical style locust plagues in North Africa, when he first noticed something killing the microbes used to kill the locusts; in other words, a complex ecosystem in which a higher level of natural enemies killed the lower-level natural enemies providing biological locust control.

During a World War I Paris dysentery outbreak, d’Herelle deduced that some patients were benefiting from phages invisibly providing biological control of the disease microbes. D’Herelle’s 1917 article on the subject for the French Academie des Sciences was titled “Sur un microbe invisible antagonistic des bacilles dysenterique” (“On an Invisible Microbe Antagonistic to Dysentery Bacteria”). “D’Herelle claimed that the antagonistic principle was filterable, living and organized, and hence a microbe,” wrote medical historian Ton Van Helvoort. D’Herelle “thought the living nature of the principle was proved by the possibility of transmitting it in a series of cultures of dysentery bacilli.”

Albert Einstein, who won a Nobel Prize for proving unseen forces and counter-intuitive phenomena based on mathematical constructs, agreed with d’Herelle. “The statistical explanation, which d’Herelle argued intuitively, is based on the properties of sampling that can be described by the mathematical expression known as the Poisson distribution,” wrote William Summers in his book, Felix d’Herelle and the Origins of Molecular Biology. “D’Herelle bolstered not only this argument but his own status with his well-known footnote giving Einstein’s opinion of this experiment: ‘In discussing this question with my colleague, Professor Einstein, he told me, as a physicist, he would consider this experiment as demonstrating the discontinuity of the bacteriophage. I was very glad to see how this deservedly-famous mathematician evaluated my experimental demonstration, for I do not believe that there are a great many biological experiments whose nature satisfies a physicist’…Since we have now presented the evidence proving the corpuscular nature of the bacteriophage we will no longer make use of such vague expressions as bacteriophage ‘liquid,’ ‘Fluid,’ or ‘filtrate,’ but will employ instead the more precise term’…The validity of the plaque counting assay and corpuscular nature of phage, however, would remain controversial and divide phage workers into two camps until the early 1940s.”

“The bacteriophage phenomenon was the observation that an abundant and therefore cloudy bacterial culture lysed within a short time to a clear solution under the influence of a filterable lytic ‘principle’,” wrote medical historian Ton van Helvoort. “The interpretation of this phenomenon gave rise to two main opposing positions, represented by Felix d’Herelle and Jules Bordet, who clashed heavily. In 1917, d’Herelle proposed the term “bacteriophage” for the lytic principle and was convinced it was to be characterized as a filterable virus which could lyse the bacterial culture. Therefore, this lysis was a virus disease of the bacteria which he named bacteriophagy. In the 1920s this interpretation was severely criticized by, among others, the bacteriologist and serologist Jules Bordet, who received the Nobel Prize for Medicine in 1919. Bordet’s view was that bacteriophagy was linked with the metabolism of the bacterium, while the involvement of a virus was rejected.” The dispute morphed into a personal vendetta against d’Herelle, whose strong personality was perhaps hated as much as his phage theories and his views on the dangers of vaccination that were considered heretical by the era’s Nobel Prize-winning immunologists.

According to medical historian Dottore Emiliano Fruciano: “In presenting his concepts to the scientific and world community, d’Herelle connected his phage interventions to a theoretical system that clashed with those held by institutional medical science. d’Herelle thought that the reason for natural recovery was not the humoral and cellular mechanisms activated by the immune system, but rather the presence of a virulent phage for the pathogenic bacterium in the host. His observations led him to believe that phage was a common guest of every organism from man to silkworm…d’Herelle concluded that phage was the exogenous agent of natural recovery, leading to ‘spontaneous recovery’…

“Recovery was a case of the prevalence of phage over the bacterium, and death was a case of the prevalence of bacterium over phage,” wrote Fruciano. “Furthermore, d’Herelle hypothesized that phage was able to spread among ill people, mainly via stool; thus, a lack of hygiene, while contributing to infection, would also lead to recovery; phage would have been the reason for the end of epidemics. This characteristic made phage, the recovery agent, transmissible between individuals, just like the agent of disease…

“In support of his theory of natural recovery, d’Herelle cited exemplary phenomena, including recovery following exposure to cholera. In cholera, patients generally convalesced after two or three days (sometimes within 12 hours) of initial symptoms; even ‘artificial’ recoveries through phage therapy often occurred after 24 hours. However, according to d’Herelle, observations from many animal diseases had demonstrated that it took many more days for immunity to become effective in the fight against infection. To explain natural recovery through the mechanisms of immunity was not possible because of the timing.

“Moreover, in diseases such as typhus and plague, which are characterized by strong immunity, relapses were possible during convalescence. This would mean that the patient, although convalescing, was still not immune. In these kinds of pathologies, typically typhus and plague, immunity usually lasts forever, yet immunity only comes into play 20 days following convalescence. According to d’Herelle, ‘Immunity, far from being the cause of recovery, is a consequence of recovery’. Further confirmation of d’Herelle’s theory was given by the statistics of the three hospitals in Calcutta, India. Paradoxically, the lowest rate of mortality for cholera (27%) was recorded at the hospital for poor people, the Campbell Hospital, while the highest rate of mortality (86%) was recorded at a hospital for rich people, the European Hospital – a hospital recognized in 1926 for its wealthy patients and hygienic conditions. There were fewer deaths at the hospital where care and hygiene were poor, that is, where the possibility for the development and dissemination of virulent phage or the recovery agent were best.”

The cholera and phage biocontrol case in general became intolerably heretical to many in the scientific medical establishment, what with d’Herelle’s warnings against the dangers of conventional vaccinations and the radical challenge to conventional consensus medical theories supported by immunologists who had won Nobel Prizes in medicine, said Fruciano: “According to d’Herelle, immunity and recovery were two different processes; only after the bacteriolytic action of phage could immunity be developed. Furthermore, there were two kinds of immunity: heterologous immunity, linked to the presence of phage activity against the pathogen, and homologous immunity, linked to immune system activity.

“…man contracts cholera because his immune system is not able to neutralize the bacterium. In d’Herelle’s opinion, in the case of patients with cholera, recovery occurs because of the presence of a virulent phage for Vibrio cholerae as a result of heterologous immunity, not because of natural or homologous immunity. d’Herelle found that the administration of phage resulted not only in a quick recovery, but also lasting immunity. He also asserted that a suspension of phage had strong immunizing power (here in the traditional sense) because the bacterial substances dissolved by phage action induced immune system reactions… d’Herelle’s findings were contrary to the conclusions of Metchnikoff, Bordet and Ehrlich, the founders of immunology…phage therapy efficacy would have required a revision of the current explanation of natural recovery…In other words, the proof of efficacy of phage therapy was equivalent to the proof of the truthfulness of d’Herelle’s heretical theories. Thus, to verify the efficacy of phage therapy and prevention measures, the principles of modern medicine were at stake; this was a paradigm shift for the scientific community.”

Of course, in the early years of the 20th century, prior to the invention of the electron microscope to provide visual evidence, the immunologists could plausibly argue against the existence of phages (despite Einstein’s endorsement); and in the absence of modern genomics, indeed before DNA and RNA were implicated in heredity, matching the right mixture of phages with a particular disease bacterium was perhaps more art than science, an art in continuous successful practice in just a few places such as the ex-Soviet Republics of Georgia and Russia, and Poland. Also, early 20th century medical experiments are not considered rigorous by current standards. All of which makes the several hundred successful phage experiments and interventions against cholera, plague, typhus and other diseases subject to blanket dismissal; and, hence, the absence of natural biological control from Western medical practices, medical schools, and institutional research agendas.

“The following details some of the most sensational results in phage prophylaxis that would seem to contradict the eventual dismissal of d’Herelle’s works,” stated Fruciano. “In 1927, an epidemic of Asiatic cholera was halted at its start in several villages with 2000 to 3000 Punjabi inhabitants via two methods of phage prophylaxis delivery: the first was the addition of potent, individually dosed phage preparations, and the second was the administration of phage prophylaxis to local water supplies. In both scenarios, the epidemic was terminated within 48 hours; in the past, the same result was achieved through traditional interventions within a 26-day time period.

“…at the St Mary Hospital in London, England, where penicillin was first discovered, Himmelweit developed a cross-therapy involving a combination of phage and penicillin to reduce the possibility of penicillin-resistant bacteria. This solution was very promising…Above all, the conjoined administration of phage and penicillin gave positive outcomes in clinical trials. It is likely that this experimental solution worked well because, as it is known today, the mechanisms by which phage and penicillin kill bacteria are different. Unfortunately, this alternative use of phage, in combination with penicillin, has been abandoned. Why has this possibility been forgotten despite the fact that antibiotic-resistant bacteria appeared as soon as penicillin was introduced into medical practice?

“…Summers, a historian of medicine who delved deeply into d’Herelle’s scientific works, speaks of the “Soviet Taint” as a plausible reason for the lack of interest in phage as an antimicrobial agent. Following World War II, phage therapy research continued only in eastern European countries, and “d’Herelle’s Cure” became “Stalin’s Cure”. According to Summers, phage therapy and prophylactic measures became ideological symbols of divisions and disagreements between western and eastern countries, partially explaining the lack of interest in phage as an antibacterial agent in Western medical science.”


Food Sweetener Safely Slays Insects

August 27, 2015

CERTAIN SUGARS CONSIDERED SAFE as sweeteners in the human food supply can double as environmentally-friendly pest remedies, and even make biological control of insects by beneficial fungi more practical for households, farms and gardens. Considering that caffeine from coffee grounds can be used against deadly dengue mosquitoes and that a variety of traditional herbs can blast away bed bugs, insecticidal sugar compounds should come as no surprise. Perhaps the only remedy more surprising is that rain water or simulated rain sprays from hoses or irrigation equipment can safely wash away pests with no toxic pesticide residues to worry about in the environment.

Using sugars directly to slay insects is somewhat unusual. However, sugars are commonly used as attractants, for instance to lure fruit flies, moths or ants to baits and traps both for population control and as a survey method or monitoring tool. California citrus growers have a long history of using sugar sprays as an IPM (integrated pest management) strategy to lure fruit-scarring citrus thrips to organic or botanical formulations of ryania (“from woody stem and root materials of plants of the genus Ryania”) or sabadilla (alkaloids from seeds of a lily bulb, Schoenocaulon officinale). “INTEGRATED PEST MANAGEMENT implies that techniques used to manage one pest species should not disrupt techniques used to manage other pests of the same crop,” wrote J.D. Hare and Joseph Morse in the Journal of Economic Entomology. “In citrus pest management in California, this situation is well illustrated in the choice of pesticides for the management of one major pest, citrus thrips, Scirtothrips citri (Moulton), without disruption of several effective biological control agents of the other major pest, California red scale, Aonidiella aurantii (Maskell).”

That sugars can be lethal to pests and be a source of environmentally-friendly pesticides is not exactly intuitive. “Potential of the non-nutritive sweet alcohol erythritol as a human-safe insecticide” was the strangely intriguing title of Drexel University’s Sean O’Donnell’s presentation at the Entomological Society of America (ESA) annual meeting. Many of the details were previously published in PLoS ONE, an open access journal, and in part because of the origins of the research in a grade school science project by one of the researcher’s sons, aspects of the story have been widely reported in various media. “Erythritol is a zero-calorie sweetener found in fruits and fermented foods,” summarized Lauren Wolf in Chemical & Engineering News, and “is Generally Recognized As Safe by the Food & Drug Administration and has been approved as a food additive around the globe.”

“Many pesticides in current use are synthetic molecules such as organochlorine and organophosphate compounds,” and “suffer drawbacks including high production costs, concern over environmental sustainability, harmful effects on human health, targeting non-intended insect species, and the evolution of resistance among insect populations,” write the researchers in PLoS ONE. “Erythritol, a non-nutritive sugar alcohol, was toxic to the fruit fly Drosophila melanogaster. Ingested erythritol decreased fruit fly longevity in a dose-dependent manner, and erythritol was ingested by flies that had free access to control (sucrose) foods in choice and CAFE (capillary feeding assays) studies…

“We initially compared the effects of adding five different non-nutritive sugar substitutes (Truvia, Equal, Splenda, Sweet’N Low, and PureVia,” wrote the researchers in PLoS ONE. “Adult flies raised on food containing Truvia showed a significant reduction in longevity…We noted that adult flies raised on food containing Truvia displayed aberrant motor control prior to death. We therefore assayed motor reflex behavior through climbing assays…Taken together with our longevity studies, these data suggested some component of the non-nutritive sweetener Truvia was toxic to adult Drosophila melanogster, affecting both motor function and longevity of this insect…

“Our initial analysis of sweeteners included two sweeteners that contained extracts from the stevia plant, Truvia and Purevia. While adult flies raised on food containing Truvia showed a significant decrease in longevity compared to controls, this was not the case for flies raised on Purevia. These data suggest stevia plant extract was not the toxic element in these sweeteners. Purevia contains dextrose as a bulk component, while Truvia contains erythritol as a bulk component…To determine if erythritol was the toxic component of Truvia, we repeated our longevity studies on food containing equal weight/volume (0.0952 g/ml) of nutritive sugar control sucrose, and non-nutritive sweeteners Truvia, Purevia, and erythritol. We assured the flies were successfully eating the foods containing these sweeteners through dye labelling the food with a non-absorbed blue dye (blue food), and visual confirmation of blue food present in fly abdomens and proboscises daily…The average percentage of blue abdomens throughout the study were 97.46%.”

“These data confirm all treatment foods (including Truvia and erythritol treatments) were consumed by adult flies, and suggest mortality was not due to food avoidance and starvation…A large body of literature has shown that erythritol consumption by humans is very well tolerated, and, indeed, large amounts of both erythritol and Truvia are being consumed by humans every day throughout the world. Taken together, our data set the stage for investigating this compound as a novel, effective, and human safe approach for insect pest control. We suggest targeted bait presentations to fruit crop and urban insect pests are particularly promising.”

Interestingly, a few decades ago UK researchers found that the sweeteners (sugar alcohols; polyols) erythritol, glycerol and trehalose rendered more effective several insect biocontrol fungi, Beauveria bassiana, Metarhizium anisopliae and Paecilomyces farinosus. These insect-killing fungi need a relative humidity (RH) near 100% for germination of their conidia (seed-like propagules). “Conidia with higher intracellular concentrations of glycerol and erythritol germinated both more quickly and at lower water activity,” wrote UK researchers J.E. Hallsworth and N. Magan in the journal Microbiology. “This study shows for the first time that manipulating polyol content can extend the range of water availability over which fungal propagules can germinate. Physiological manipulation of conidia may improve biological control of insect pests in the field…Although fungal pathogens have been used to control insect pests for more than 100 years, pest control has been inadequate because high water availability is required for fungal germination.”

Curiously, erythritol and glycerol, besides being sweetening substances, also function as antifreeze compounds. Certain Antarctic midges, known as extremeophiles for living in an ultra-cold habitat, ingest and sequester erythritol from their food plants; and as antifreeze it protects the adult flies from freezing. Indeed, many mysteries remain. Besides being found in green plants like stevia and in lower amounts in fruits, erythritol is found in certain mushrooms, lichens and algae. Human and animal blood and tissues apparently have low endogenous levels of erythritol; and erythritol is a yeast fermentation product (hence in sake, beer, wine). In human medicine, erythritol has been used for coronary vasodilation and treating hypertension; and according to Japanese microbiologists, erythritol ingestion may mean fewer dental cavities (caries) than sucrose sugar.


Grapes Love Tobacco & Sage

June 13, 2015

GRAPE VINES GAIN and pests suffer when TOBACCO and SAGEBRUSH grow in the same neighborhood. For example, Chinese experiments show that when tobacco roots intermingle with grape roots, vineyards soils are progressively cleansed of the dreaded soil-dwelling phylloxera aphid; the same phylloxera aphid that almost completely destroyed French grape growing in the 1800s, before resistant rootstocks were discovered. In recent decades, the phylloxera aphid has evolved new forms that destroy formerly-resistant rootstocks. But on the positive side, the phylloxera plague in nineteenth century French vineyards was a major catalyst for innovations such as the development of modern scientific agriculture and modern methods for fumigating or disinfesting sick soils.

Tobacco plants get a bad rap today, as the source of abused and addictive products with adverse health effects. But it was not always so, and need not be so today, write David A. Danehower and colleagues in the book, Biologically Active Natural Products: Agrochemicals: “When Columbus first arrived on the shores of North America, he found Native Americans growing and using a plant unknown to Europeans. This plant held great spiritual significance to Native Americans. Scientists who followed in the footsteps of the early North American explorers would later name this plant tobacco. Tobacco (Nicotiana tabacum) farming began in the early 1600s near the Jamestown colony in Virginia. As the use of tobacco products for smoking, chewing, and snuff was promoted in Europe, tobacco became a leading item of commerce between the colonies and England. Notably, George Washington and Thomas Jefferson both farmed tobacco. Thus, the history of America is inextricably linked with the history of tobacco production.”

The specific idea of interplanting tobacco with grapevines to control soil pests like phylloxera aphids is apparently a recent Chinese agricultural innovation. Why no one thought of it before is a mystery, as nicotine from tobacco plants has a long history as a fumigant and sprayed insecticide; and more recently sweet “sugar esters” (fructose, glucose, fatty acids) have been singled out from among the several thousand chemical compounds in tobacco as “new” natural insecticides (some fungi and other microbes are also killed). Perhaps agricultural tradition plays a role, as the Chinese have an ancient agricultural heritage that includes pioneering biological pest control (e.g. predatory ants to control citrus orchard pests) and routinely interplanting compatible plants for their pest-fighting and mutually beneficial effects. Of course, growing cover crops and beneficial insect plants like sweet alyssum in grape rows is becoming more common. And since ancient times, the Mediterranean areas of Europe and the Middle East have had grape vineyards interspersed with oaks (corks, barrels for wine grapes), olive trees and crops such as wheat. But never before has tobacco been grown among grape vines to control soil pests. Indeed, modern farmers seem to favor pumping liquid chemicals and volatile gases into the soil to combat soil pests.

Perhaps as close as a nineteenth century French grape grower came was Bernardin Casanova of Corsica, France, who in 1881 patented a liquid mixture of grape distillates, Corsican tobacco, spurge, laurel, grain straw, burnt cork and soap that was rubbed and poured on the base of grapevines to kill phylloxera. In California, which has native plants that are every bit as insecticidal as nicotine from tobacco, the only anti-phylloxera interplanting seems to have been new resistant rootstocks to eventually take the place of the old. In essence, a concession of failure and a starting over with new rootstock (and pulling out the old phylloxera-infested vines).

Like Mr. Casanova in nineteenth century France, the modern Chinese researchers started out with a watery solution containing tobacco; but in a bit more scientific fashion with controlled tests of the tobacco solution on young greenhouse-grown grape vines. “The results showed that aqueous extracts of tobacco had certain alleviating effects on phylloxera infection,” according to a 2014 abstract from the journal Acta Entomologica Sinica. “Both the aqueous extracts of tobacco at the concentration of 20 mg/mL and 50 mg/mL had an inhibition to phylloxera infection,” with a 50% reduction in phylloxera infection within 3 weeks (along with a reduction of fungal invaders that kill injured grape roots).

Chinese tobacco-grape laboratory and field studies were also reported in the Journal of Integrative Agriculture in 2014. The lab studies indicated that tobacco extracts in water were indeed a valid herbal (botanical) remedy against phylloxera aphids. In three years of field tests with tobacco interplanted in infested grape vineyards, phylloxera infestations of grape roots steadily decreased each year. “Tobacco was used as the intercropping crop because it includes nicotine, which is a source of bio-insecticides,” said the researchers. “The production of new grape roots was significantly higher in the intercropping patterns than in the grape monoculture in 2010, 2011 and 2012, and the vines gradually renewed due to the continuous intercropping with tobacco over three years…The results indicated that the secondary metabolites of tobacco roots had released to soil and got to the target pest.” Tobacco intercropping effects on grape plants was also measurable in terms of “cluster number per plant, cluster weight, cluster length, cluster width, berry number per cluster, mean berry diameter in the mid portions of the cluster, carbohydrate content, fruit color index, leaf width and branch diameter.” The researchers expect that this “Successful intercropping with tobacco” will stimulate more research with other insecticidal plants to disinfest vineyard soils.

We could probably end the blog item here, or have a second article as part II, but we have some interesting interactions among sagebrush and tobacco plants that can spillover to grape vineyards. Oddly enough, sagebrush and tobacco seem to get along very well. According to M.E. Maffei, writing in the South African Journal of Botany: “Aerial interaction of the wild tobacco (Nicotiana attenuata) and sagebrush (Artemisia tridentata subsp.) is the best-documented example of between-plant signaling via above-ground VOCs (Volatile Organic Compounds) in nature.” Wounded or “Clipped sagebrush emits many volatiles, including methyl jasmonate, methacrolein, terpenoids, and green leaf volatiles.” These sagebrush volatiles (VOCs) stimulate nearby tobacco plants to become less hospitable to caterpillar pests (fewer in number). The process is called priming and results in plants producing more chemicals deleterious to pests. For readers desiring all the details and more theory: In 2006, Kessler et al. published in a journal called Oecologia under the title “Priming of plant defense responses in nature by airborne signaling between Artemisia tridentata and Nicotiana attenuata.”

Big Sagebrush, known scientifically as Artemisia tridentata, is a native North American plant that can reach 4 meters in height and live from 30 to over 200 years in arid desert environments by using hydraulic lift to pump water from deep soil layers. The plants are a rich and underutilized source of medicinal compounds, insecticides, fungicides, natural preservatives, etc. Worldwide there are at least 500 Artemisia sagebrush species, many used in traditional medicines (e.g. China), cosmetics, insect repellents, and as spices and flavorings in foods. For example, Artemisia annua has attracted attention to combat malaria. Readers desiring a crash course in Artemisia species and their bio-active essential oils will find it online in an excellent 24-page review article in a journal called Molecules.

Big Sagebrush is “found in arid regions of North America from steppe to subalpine zones, dry shrub lands, foothills, rocky outcrops, scablands, and valleys,” wrote Christina Turi and colleagues in 2014 in the journal Plant Signaling & Behavior. “Traditionally, species of Big Sagebrush have been used as a ceremonial medicine to treat headaches or protect individuals from metaphysical forces. A total of 220 phytochemicals have been described in A. tridentata and related species in the Tridentatae. Recently, the neurologically active compounds melatonin (MEL), serotonin (5HT), and acetylcholine (Ach) were identified and quantified.” In other words, sagebrush plants and human brains and nervous systems have a lot in common.

Indeed, galanthamine, a botanical drug treatment for mild to moderate Alzheimer disease, can also be used to “treat” sagebrush. Galanthamine, which is named after the snowdrop plants (Galanthus species) where it was discovered, is also found in Narcissus and other common bulbs. Galanthamine is, according to researchers Turi et al., “a naturally occurring acetylcholinesterase (AchE) inhibitor that has been well established as a drug for treatment of mild to moderate Alzheimer disease.” Why bulb plants produce chemicals affecting both Alzheimer disease (human nervous systems) and sagebrush plants is a good question. One theory is that plants release these chemicals into the environment to communicate with and influence the behavior of other plants, and also perhaps deter or otherwise influence herbivorous animals. Environmentalists, overly preoccupied with worries about carbon dioxide and GMOs, might ponder the fact that human chemicals with medicinal effects released into the environment might be the bigger threat, affecting plants and ecosystems in ways not yet fully appreciated that may comeback to bite us.

The Western USA is known for its vast expanses, perhaps 50 million acres with Big Sagebrush, some of which is being displaced for vineyards in isolated valleys in the Pacific Northwest. I particularly like the description of the Big Sagebrush ecosystem at the Sage Grouse Initiative: “To many of us, sagebrush country symbolizes the wild, wide-open spaces of the West, populated by scattered herds of cattle and sheep, a few pronghorn antelope, and a loose-knit community of rugged ranchers. When you stand in the midst of the arid western range, dusty gray-green sagebrush stretches to the horizon in a boundless, tranquil sea. Your first impression may be of sameness and lifelessness—a monotony of low shrubs, the over-reaching sky, a scattering of little brown birds darting away through the brush, and that heady, ever-present sage perfume.”

About 90% of the native sagebrush steppe habitat in the eastern Washington grape growing area was removed to make way for the vineyards. But the 10% remaining sagebrush habitat may have important ecological benefits, such as improved natural or biological pest control in the vineyards. One suggestion is to leave some of the native Big Sagebrush around vineyards, for its beneficial ecological effects. “Perennial crop systems such as wine grapes have begun using cover crops and hedgerows to increase beneficial insects and promote sustainable vineyard management in areas like New Zealand and California,” Washington State University researcher Katherine Buckley told the 2014 Entomological Society of America (ESA) annual meeting in Portland, Oregon. “However, in arid wine growing regions such as eastern Washington, cover crops are often prohibitively expensive due to water costs. We wanted to determine if native plants, which require little or no irrigation, could be used to increase beneficial insects and enhance conservation biological control of vineyard pests in eastern Washington.”

The native sagebrush steppe ecosystem has a wide range of plants, but is characterized by species such as big sagebrush (Artemisia tridentata), rabbitbrush (e.g. Chrysothamnus, Ericameria spp.), bitterbrush (Purshia spp.) and perennial bunchgrasses (e.g. Agropyron, Stipa, Festuca, Koeleria, Poa spp.). The Big Sagebrush ecosystem is richer in species than meets the eye at first glance. Over 100 species of birds (e.g. sage grouse, sage thrasher, sage sparrow and Brewer’s sparrow) forage and nest in sagebrush communities, and they could provide a lot of insect biocontrol at less cost and with less environmental impact than chemical sprays.

A U.S. Forest Service report called Big Sagebrush a keystone species and “a nursing mother” to “31 species of fungi, 52 species of aphids, 10 species of insects that feed on aphids, 42 species of midges and fruit flies that induce galls, 20 species of insects that parasitize the gall inducers, 6 species of insects that hibernate in big sagebrush galls, 18 species of beetles, 13 species of grasshoppers, 13 species of shield-back katydids, 16 species of thrips, 74 species of spiders, 24 species of lichens, 16 species of paintbrushes, 7 species of owl-clovers, 5 species of bird’s beaks, 3 species of broom rapes, and a host of large and small mammals, birds, and reptiles.”

“After locating vineyards with some form of native habitat restoration in four different growing regions of eastern Washington, yellow sticky traps and leaf samples were used to monitor beneficial and pest insect numbers in the habitat restored vineyards and nearby conventional vineyards over a three year period,” said Buckley. The native plants, which are adapted to the region’s hot summers and cold winters, are home to at least 133 insect species. Native habitat vineyards had fewer pest insect species; and higher populations and a higher diversity of beneficial insects. Anagrus wasps, which are known to parasitize pesky grape leafhoppers, were most abundant in Big Sagebrush. More amazingly, this leafhopper biocontrol wasp was found year-round in Big Sagebrush, even when the plant was not flowering. No other plant, not even the photogenic wild roses planted at the end of vineyard rows and admired by tourists, hosted the tiny leafhopper biocontrol wasp year-round.

Garden herbs such as thyme (Thymus ssp.), mugwort (Artemisia ssp.) and fennel (Foeniculum ssp.) have all been tested in vineyard interrows because they are fungicidal against Botrytis cinerea, a fungus attacking grape clusters, and boost soil micro-nutrients like copper, manganese and zinc. Maybe at some point in time, the Chinese interplantings of tobacco and alternating strips of Big Sagebrush (or other Artemisia species) and garden herbs will all get integrated together with other cover crops and native hedgerows into grape vineyards for a more biological or natural approach to agriculture. With sagebrush and tobacco, we have only scratched the surface of vineyard possibilities.


Silicon Bed Bug Weaponry

May 4, 2015

BED BUGS CAN be spiked and trapped by tiny spears like leaf hairs, and can become dehydrated or dessicated and rendered harmless by certain forms of silicon, the second most abundant element in planet Earth’s crust (28%) after oxygen (47%). That silicon can be the bane of bed bugs is indeed odd when one considers that silicon permeates our world from beach sands, opals, agates and quartz crystals to sandpaper, semiconductors, glasses, ceramics, optical fibers and cosmetic products. Indeed, the famous French scientist and silkworm entomologist, Louis Pasteur, whose name has become synonymous with the germ theory of medicine, predicted silicon’s eventual service in human medicine; though Pasteur was probably not thinking along the lines of silica gels and desiccant diatomaceous earth dusts as remedies for the 21st century’s worldwide medical plague of bed bugs.

Despite its commonness in nature and the human environment and potential uses in human medicine, the use of silicon products comes with caveats to users, who might want to wear sufficient protective clothing and respirators to avoid inhaling the products. Strangely enough, that much maligned metabolic waste product, carbon dioxide, which along with sunlight is essential to photosynthesis and life on planet Earth, is perhaps a safer component (e.g. as a lure or attractant) when integrated into bed bug traps. Food grade diatomaceous earth made from freshwater diatoms is considered relatively nontoxic; whereas filtering grade diatomaceous earth (e.g. the type used for swimming pool filters) is a crystalline form with inhalation toxicity.

“Louis Pasteur (1822-95) said that silicon would prove to be a treatment for many diseases and in the first quarter of the twentieth century there were numerous reports by French and German doctors of sodium silicate being used successfully to treat conditions such as high blood pressure and dermatitis,” wrote British chemist John Emsley in his superb compendium, Nature’s Building Blocks (An A-Z Guide to the Elements). “By 1930, such treatments were seen to have been in vain and the medication fell out of favor. So things rested, until the discovery that silicon might have a role to play in human metabolism, and then followed suggestions that it could have a role in conditions such as arthritis and Alzheimer’s disease, but no new treatment based on these suggestions has yet emerged. Meanwhile, silicon continues to be linked with a disease of its own: silicosis. Miners, stone-cutters, sand-blasters and metal-grinders develop this lung condition which is a recognized occupational disorder caused by the inhalation of minute particles of silica…” Symptoms include coughing, wheezing and shortness of breath; a more aggressive form of silicosis associated with certain types of asbestos can develop into lung cancer and has been a rich source of litigation for occupational exposure in the USA.

While silica products should be used sparingly (a caution that should also apply to most sprays) or not at all by some people (e.g. existing respiratory problems; perhaps seek a medical opinion before using), they might prove for many others the tipping point for winning the bed bug war as part of an integrated approach that controls bed bugs (many of which are pesticide resistant) using a multiple arsenal of weapons including herbal oils, clutter reduction, heat, sealing crack and crevice harborages, traps, pheromones, carbon dioxide, vacuuming under baseboards, etc.

At the 2014 Entomological Society of America (ESA) annual meeting, Kyeong-Yeoll Lee of South Korea’s Kyungpook National University (Daegu) reported that silica in the form of diatomaceous earth (Perma-Guard(TM) or Fossil-Shell(R)) acted as a synergist when heat (hot air) fumigations substituted for chemical fumigants such as methyl bromide. Though the test insect was Indian meal moth, a worldwide pest of stored grain and many other packaged agricultural products, it would not be surprising to find that heat treatments combined with silica products like diatomaceous earth will also prove efficacious and perhaps also synergistic against bed bugs. Indeed, heat treatments may induce bed bugs to move around more, which could hasten contacting diatomaceous earth and water loss.

At the same 2014 ESA meeting, Virginia Tech (Blacksburg, VA) researcher Molly Stedfast provided some impressive results via the time-consuming process of first educating apartment residents about bed bugs and then painstakingly vacuuming along baseboards to suck up as many bed bugs as possible before applying the silica products under the baseboards to further reduce bed bug populations. This integrated (IPM; integrated pest management) approach required quite a bit of manual labor, as furniture had to be moved to gain access to the baseboards before vacuuming and then applying silica gel or dust products.

Stedfast tested two silica products, Mother Earth(TM) D, a highly-absorptive desiccant dust made from 100% freshwater diatomaceous earth, and CimeXa(TM) Insecticide Dust, a 100% amorphous silica gel. The silica dust or gel injures the insect cuticle (outer protective “skin”), letting water leak out and leading to dehydration (providing relative humidity is not extremely high, above 81%; and free water is unavailable). Both the diatomaceous earth and silica gel products were “very effective at killing bed bugs even at 10% of the label rate.” Going above the label rate was a waste of resources, as only so much product can contaminate the bed bugs. Bed bugs can die within 24 hours of contacting the silica products, but air currents that blow the dusts around can be a problem; also the products need to stay moist and not dry out to be effective. Among Stedfast’s biggest headaches is the application equipment, which was not very robust.

The patent literature reveals that inventors such as Roderick William Phillips in Vancouver are working on improved spray apparatuses for applying diatomaceous earth: “There is disclosed a spray apparatus for holding contents comprising diatomaceous earth and a compressed propellant for propelling the diatomaceous earth. There is also disclosed use of diatomaceous earth to control a population of bedbugs…diatomaceous earth, a naturally occurring siliceous sedimentary rock that includes fossilized remains of diatoms. However, known methods of applying diatomaceous earth can be cumbersome. For example, known methods of applying diatomaceous earth may undesirably require handling the diatomaceous earth, for example to transfer the diatomaceous earth from a container not having an applicator to a separate applicator apparatus. Also, known applicator apparatuses may apply diatomaceous earth unevenly, which may be wasteful or ineffective. In general, known methods of applying diatomaceous earth may be sufficiently complex so as to require professional involvement, which may undesirably add to cost and delay of bedbug treatment. Also, numerous types of diatomaceous earth are available, and different types of diatomaceous earth vary widely and significantly from each other. It has been estimated that there are approximately 100,000 extant diatom species…and may vary widely and significantly in size and shape across a very large number of diatom species…”

At the University of British Columbia (Vancouver), Yasmin Akhtar and Murray Isman demonstrated that both diatomaceous earth and herbal or botanical compounds such as neem, ryania and rotenone are to varying degrees transported by adult bed bugs and contaminate other adults and younger bed bug nymphs. “Our data clearly demonstrate horizontal transfer of diatomaceous earth and botanical insecticides in the common bed bug,” said Akhtar and Isman. “Use of a fluorescent dust provided visual confirmation that contaminated bed bugs transfer dust to untreated bed bugs in harborage. This result is important because bedbugs live in hard-to-reach places and interaction between conspecifics can be exploited for delivery and dissemination of management products directed at this public health pest…This result is important because bedbugs live in hard-to-reach places (cracks, crevices, picture frames, books, furniture) and as such interaction between the members of the colony can be exploited for delivery and dissemination of control products.”

At the 2014 ESA annual meeting, Akhtar suggested protecting travelers and suppressing bed bug transit by building diatomaceous earth into luggage, mattresses and fabrics. Diatomaceous earth provided 96% repellence; bed bug mortality was zero at 24 hours, but 93% after 120 hours. Diatomaceous earth could also be applied to box springs, dressers and headboards, and under carpets and inside drywall. A diatomaceous earth aerosol provided 81% bed bug mortality at 30 days, and was still active and being transferred from dead bed bugs to live bed bugs.

Diatom species mined for diatomaceous earth are stunning in their architectural variety and beauty. Ultimately, the silicon secrets of living diatoms has the potential to transform “the manufacture of siloxane-based semiconductors, glasses, ceramics, plastics, elastomers, resins, mesoporous molecular sieves and catalysts, optical fibers and coatings, insulators, moisture shields, photoluminescent polymers, and cosmetics,” wrote UCSB marine scientist Daniel E. Morse. “The manufacture of these materials typically requires high temperatures, high pressures or the use of caustic chemicals. By contrast, the biological production of amorphous silica, the simplest siloxane [(SiO2)n], is accomplished under mild physiological conditions, producing a remarkable diversity of exquisitely structured shells, spines, fibers and granules in many protists, diatoms, sponges, molluscs and higher plants. These biologically produced silicas exhibit a genetically controlled precision of nanoscale architecture that, in many cases, exceeds the capabilities of present-day human engineering. Furthermore, the biological productivity of siloxanes occurs on an enormous scale globally, yielding gigatons per year of silica deposits on the floor of the ocean. Diatomaceous earth (composed of the nanoporous skeletons of diatoms) is mined in great quantities from vast primordial deposits of this biogenic silica.”


Herbal Oils Blast Bed Bugs

March 28, 2015

HERBAL OILS such as NEEM can reduce bed bug populations when integrated with other pest control technologies such as traps. As desperation hits with more bed bug populations resistant to more conventional synthetic pesticides, more herb and essential oil formulations and fumigations, as well as silicon dioxide-based gels and dusts such as diatomaceous earth, are being integrated with other bed bug remedies such as clutter reduction and heat fumigation.

Those in thrall to chemical industry protocols adhere to the standard that a remedy must kill 95% in laboratory tests. But it is most often a hypocritical standard, as over time bed bugs are almost guaranteed to become genetically selected for resistance to widely used synthetic pesticides. According to Virginia Tech researchers: “A frightening resurgence of bed bug infestations has occurred over the last 10 years in the U.S. and current chemical methods have been inadequate for controlling this pest due to widespread insecticide resistance…While DDT was initially effective for bed bug control, resistance to the cyclodienes was well documented among different bed bug populations by 1958…bed bugs had developed resistance to organophosphate insecticides, including malathion by the 1960s…While there have been many hypotheses regarding the cause of the bed bug resurgence, the cause is at least partially explained by bed bug resistance to insecticides, in this case, those in the pyrethroid class,” including deltamethrin resistance in New York City bed bugs.

To that conclusion, I would add “over-reliance on synthetic chemical pesticides” to the exclusion of designing habitations to be inhospitable to bed bugs and alternative control methods. Oddly enough, herbal remedies not killing 95% are often subject to persecutory calls of marketplace banishment by the EPA, FDA, FTC or one of the myriad other USA.gov regulatory bureaucracies. An Alternative in the Internet age is letting people decide for themselves via Internet search engines before buying. To some extent, government regulation of herbal pest control efficacy is unnecessary when scientific test results can be posted on the Internet and debated.

An integrative approach can make excellent use of herbal remedies providing perhaps 40% or 60% bed bug reduction; in conjunction with heat treatments, sharp silicon dioxide crystals and other remedies that collectively might add another 30%, 40% or 50% bed bug reduction. It’s all mathematics, which many people hate; but nonetheless a 60% bed bug reduction from an herbal remedy combined with a 40% reduction from clutter reduction, heat fumigation or traps can easily equal over 95% control (the laboratory standard adhered to by those one-trick chemical ponies sometimes called “nozzle heads”).

In other words, herbal oils and other alternative treatments can leverage themselves when intelligently combined with other pest control methods such as heat, clutter reduction and traps. That should be intuitive, but it runs counter to the entomology training of the average PhD in the USA. The late “Professor (Robert) van den Bosch of the University of California was one of the developers of Integrated Pest Management” (IPM) and an advocate of biological controls; and he made the case for a multi-faceted approach to cotton and food crop pests long ago in books like The Pesticide Conspiracy (University of California Press).

Bed bugs and the urban environment of hotels, apartments, cracks, crevices, mattresses, trains, buses, backpacks and luggage of course present a different set of problems than a homogeneous field of crops or a laboratory spray arena. But you be the judge of whether herbal fumigations work against bed bugs: At the Entomological Society of America annual meeting, Korean researcher Jun-Ran Kim (Rural Develop Admin, Suwon-si Gyeonggi-do, South Korea) compared 120 herbal or botanical essential oils to the best conventional pesticides for controlling insecticide-susceptible and insecticide-resistant adult bed bugs hiding in protected places (as bed bugs do; e.g. cracks, crevices, inside electrical sockets).

Kim singled out two essential oils, those from peppermint (Mentha piperita) and myrtle (Myrtus communis) plants, as most effective and worth further development as bed bug fumigants. So, should the headline read: “Essential Oils a Failure as Bed Bug Fumigants,” as 118 of 120 essential oils did not make the cut. Indeed, fewer than 2% of the botanical oils tested, peppermint and myrtle, were singled out as potential bed bug fumigants. Or should the headline read: “Essential Oils Effective Bed Bug Fumigants,” or “Peppermint and Myrtle Oils Prove Essential Oils Can Work as Bed Bug Fumigants.”

Rue, an ancient herb, needs to be tested against bed bugs. Natural products researchers report: “An infusion of Ruta chalepensis leaves rubbed onto skin has been purported to be repellent to mosquitoes and other insects by farmers and shepherds in rural and mountainous areas of Marche and Latium, Central Italy. In the same Italian countryside, Ruta graveolens leaves were set under the bed to repel bugs and mice (Guarrera 1999). A decoction of Ruta species also has been used topically against scabies, lice, and fleas, to repel insects and to treat intestinal worms in livestock.”

Intriguingly, rather than following up on rue under the bed to fight bed bugs, Italian researchers veered off in another direction: Rue, as a sustainable weed control alternative for corn field weeds such as purslane and pigweed: “Poisonous plants are neglected sources of natural herbicides. An infusion of such a plant rue (Ruta graveolens L.) was tested…rue infusion (100 g/l) and its isolated allelochemicals…open up a promising avenue in the search of natural herbicides.”

Other researchers envision the disease-fighting properties of herbs such as rue and powders such as sodium bicarbonate (baking soda or bicarbonate of soda) being harnessed as alternatives to synthetic fungicides. Indeed, in organic and sustainable conventional farming, rue “at low rates…may lessen the onset of fungicide resistance” against powdery mildew, brown spot and other plant diseases in diverse crops, including strawberries.

Italian researcher Giovanni Aliottal and colleagues in a paper titled “Historical Examples of Allelopathy and Ethnobotany from the Mediterranean Region,” write: “Ruta graveolens L. (Rutaceae), or common rue, originating in Southern Europe, is an evergreen shrub with bluish-green leaves that emits a powerful odour and has a bitter taste. The plant is cited in the ancient herbals and has deep roots in folklore, alchemy and even demonology. Rue has been regarded from the earliest time as successful in warding off contagion and preventing the attacks of fleas and other noxious insects. The name rue derives from the Greek “reuo” (= to set free), because the plant is efficacious in various diseases. Rue was the chief ingredient of the famous antidote to poison used by Mithridates. It was also known to produce erythema and pustular eruptions on human skin. Many remedies containing rue as well as its abortive properties were mentioned by Pliny the Elder in his Naturalis Historia (XX, 143). In Europe, rue was considered a powerful defense against witches during the Middle Ages. Piperno, a Neapolitan physician, in 1625, recommended rue as a treatment for epilepsy and vertigo. Today, the aerial parts of the plant are eaten in Italian salads, and are said to preserve the eyesight. Rue is currently mentioned in the pharmacopoeias of 28 countries where it is considered mainly as a stimulating, antispasmodic, diuretic and emmenagogue. Moreover, fresh and dried leaves are used to preserve and to flavour beverages and foods such as liquor (grappa) and wine, cheese and meat.”

Ruta graveolens is the scientific name for garden rue or herb-of-grace, one of about 1,500 species in the plant family Rutaceae (includes oranges, lemons, other citrus). A native of the Balkans and southeastern Europe grown worldwide, rue is known as sudab or sadab in India, arvada in Tamil, aruda in Singhalese, gedung minggu in Javanese and geruda in Malay. Ruta chalepensis is the scientific name for fringed rue, Aleppo rue or Egyptian rue. Rue researchers D. H. Tejavathil and B. L. Manjula in India summarize: “Ruta graveolens L., a member of Rutaceae, is well known for its wide utilities such as ornamental, aromatic and culinary in addition to medicinal properties. Medicinal value of this taxon is attributed to the accumulation of flavonoids, furanocoumarins, acridine alkaloids, furanoquinolins and also essential oils which led to its recognition as one of the sought after traditional medicinal plants by pharmaceuticals.” Perhaps a bit dangerous, too; according to Egyptian researchers: “On moist skin in direct sunlight, it leads to photosensitivity. The essential oil is a central nervous system depressant and at high doses has become a narcotic.”

A major rue essential oil component, 2-undecanone, is nicely summarized in wikipedia: “2-Undecanone is used in the perfumery and flavoring industries, but because of its strong odor it is primarily used as an insect repellent or animal repellent. Typically, 1–2% concentrations of 2-undecanone are found in dog and cat repellents…” According to its web site claiming “invention” by Dr. R. Michael Roe and referencing 3 patents: “North Carolina State University is currently seeking an industry partner to commercialize a novel, natural insect repellent for mosquitoes, ticks, chiggers, bedbugs, house dust mites, cockroaches, and other pests…A researcher at North Carolina State University has discovered that undecanone and related structures are repellents of mosquitoes, ticks, bed bugs, cockroaches, thrips, aphids, deer flies, gnats and other animals. In some tests, these compounds were found to be more effective than DEET…”

The Flowers of Chania web site provides a nice overview of rue species used as medicine in Crete, grown in Netherlands botanical gardens, and mentioned in Shakespeare’s Hamlet. Unlike the Balkan bean leaf remedy for spearing bed bugs, which has recently sparked the interest of those desperate for bed bug remedies, medicinal plants in the rue family known since ancient times have escaped scientific scrutiny against bed bugs. Probably much to the delight of bed bugs worldwide. According to researchers in India, “The most frequent intentional use of the plant has been for induction of abortion.” If only that powerful rue activity could be integrated to naturally abort bed bug populations just enough to allow humans a more bite-free sleep.

On the Internet are a varied array of commercial products with herbal essential oil and soap (detergent) ingredients sold for potential use against bed bugs (and usually other pests, as well). The herbal ingredients do not need extensive safety testing, as they are GRAS (Generally Recognized as Safe) substances commonly found in foods, cosmetics, etc.

According to the USA FDA (Food and Drug Administration) web site: ““GRAS” is an acronym for the phrase Generally Recognized As Safe. Under sections 201(s) and 409 of the Federal Food, Drug, and Cosmetic Act (the Act), any substance that is intentionally added to food is a food additive, that is subject to premarket review and approval by FDA, unless the substance is generally recognized, among qualified experts, as having been adequately shown to be safe under the conditions of its intended use, or unless the use of the substance is otherwise excluded from the definition of a food additive. Under sections 201(s) and 409 of the Act, and FDA’s implementing regulations in 21 CFR 170.3 and 21 CFR 170.30, the use of a food substance may be GRAS either through scientific procedures or, for a substance used in food before 1958, through experience based on common use in food.”

In other words, if there is a long tradition of eating the stuff and smearing it on your body, it is likely not to need hundreds of millions of dollars and decades of testing and regulatory agency compliance like a pharmaceutical product. So, you don’t have to wait 15 years for a bed bug remedy that will be several times more costly (to recoup the regulatory expenses) than what is already available. Being publicly sold on the Internet, samples of these GRAS pesticide products can often be obtained free of charge by researchers for scientific studies. Sometimes the studies, even if taxpayer or public funded, are published in respected commercial journals and hidden from public perusal behind formidable paywalls. But Internet search engines can usually at least turn up abstracts, media reports and summaries of varying quality and usefulness.

Rutgers researchers compared 11 herbal and detergent products (e.g. Sodium Lauryl Sulfate) and two synthetic pesticide products against bed bugs. A nice summary by the researchers published in an industry trade publication and titled “Natural Pesticides for Bed Bug Control: DO THEY WORK?” was made freely accessible via the Internet. Bed bugs were placed in laboratory chambers offering no escape from spray contact; a valid approach for most product comparisons. But given that many bed bug populations are pesticide resistant and that in real rooms bed bugs hide and avoid spray contact, real world results are usually lower than the lab numbers. These are more or less truisms, for both botanical and synthetic pesticide products. Which is why pest control operators often are called back to spray multiple times over several months or years; and why you need an integrative approach (relying on more than just sprays) and plenty of patience to rid yourself of bed bug infestations. A quick overview of integrative bed bug alternatives with a resource list is found in the Jan. 2015 issue of the IPM Practitioner (as of this writing, still available for free Internet download).

According to the Rutgers researchers, Temprid SC [Imidacloprid (21%) and Beta-Cyfluthrin (10.5%)] killed 100% of exposed adult bed bugs coming in contact with the spray in three days, and “was significantly more effective than Demand CS” [Lambda-Cyhalothrin (9.8%)]. The best herbal formulations were a bit slower: “EcoRaider and Bed Bug Patrol were the most effective biopesticides in both tests. EcoRaider [Geraniol (1%), Cedar Extract (1%) and Sodium Lauryl Sulfate (2%)] caused 100 percent mortality after 10 days in both tests. Bed Bug Patrol [Clove Oil (0.003%), Peppermint Oil (1%) and Sodium Lauryl Sulfate (1.3%] caused an average of 92 percent and 91 percent mortality after 10 days in the first and second experiment, respectively. Neither of these two products caused more than 75 percent mortality at three days after treatment…Bed Bug Bully [Mint Oil (0.25%), Clove Oil (0.3%), Citronella Oil (0.4%) and Rosemary Oil (0.4%)] caused 60 percent mortality after 10 days.”

Thus, the need for a patience and a multi-faceted, integrative approach to bed bug control using herbal or synthetic pesticides, tiny leaf hair-like spikes, CO2, traps, heat, cold, steam, mattress encasements, vacuuming, pheromones, clutter reduction, diatomaceous earth, silica gels, etc. If winning the war against bed bugs were easy, the insects would have been extinct long ago and you would not be reading this.


Organic Dairies Suck Flies (CowVac)

December 5, 2014

Rest assured, a CowVac is not a veterinary vaccine of some sort that magically provides insect control or renders cows autistic. Rather, it is about producing organic milk and organic milk products like butter and yogurt. A CowVac is a suction or vacuum device incorporated into a larger trapping apparatus that removes blood-sucking flies that can be an even worse livestock plague than mosquitoes or ticks. Besides being bad economics (too expensive), pesticides repeatedly applied at ever higher doses quickly select for pesticide-resistant biting flies; i.e the flies become immune. Which is not to say that insects will not develop some ingenious solution, like holding on tighter, to avoid being sucked up by strong suction. But at least development of stronger suction devices and better ways to knock insects off animals would not add pesticide residues to the environment, food chain and human diets. A human equivalent, awaiting invention, would be an enclosure of some sort designed to knockoff and suck up (vacuum off) bed bugs before they bite (see previous blog, on bed bug desperation time innovative research).

“Seven years in the making: The Cow-Vac removes horn flies from dairy cattle” was the title of a special display at a members symposium “Honoring the Career and Contributions of Veterinary Entomologist Donald A. Rutz” at the Entomological Society of America (ESA) annual meeting in the beer brewing capital of the world, Portland, Oregon. On its web site, the Center for Environmental Farming Systems (CEFS) at North Carolina State University (NCSU) in Raleigh reports: “This innovative solution is now part of routine cattle management at the CEFS Dairy Unit and has allowed the herd to be insecticide-free for 5 years.” In other words, this “alternative fly management system” designed by Steve Denning and D. Wes Watson demonstrated “the feasibility of producing organic milk.”

“The trap removed between 1.3 and 2.5 million flies annually from the research station cattle,” Denning and Watson reported to the ESA in Portland. “Prior to the installation of the trap in 2007, the cattle routinely had horn fly populations above 1000 flies per animal and would require insecticide applications for horn fly control. With a vacuum trap in place, dairy cattle at CEFS have not required or have been treated with an insecticide.” With each of the thousand horn flies sucking blood 10-12 times per day, the blood loss and associated problems were huge (USA estimated losses are over $2.26 billion per year), and organic animal agriculture was considered questionable.

“The first walk-through pasture fly trap consisted of a covered structure designed to brush flies from the animals as they passed through, with the fleeing flies captured in the screened hollow walls,” reported Denning and Watson at the ESA meeting in Portland. “Modifications to the Bruce trap have been introduced over the years. These modified traps employ the same basic mode of action; curtains to dislodge flies and light, either natural or fluorescent, to attract flies to a cage, or bug zapper. In addition to curtains, the CowVac uses air pressure to dislodge flies, and vacuum to capture flies, trapping them in a chamber until death.” So far, the Animal Rights movement has yet to recognize a right to food (animal blood, in this case) for biting flies (also animals); and the flies die a natural death from lack of animal blood as a food source. Cruelty to animals (flies), perhaps; and fodder for an ethics debate. But if you want organic milk, butter, meat, yogurt, etc…

There are YouTube videos on the vacuum trap, and the Northeast Organic Dairy Producers Alliance has an in-depth article on the CowVac and its development by fly biocontrol specialist Tom Spalding of Spalding Labs: “…the Horn Fly is very tough to control. It’s resistant to most every chemical control. It only reproduces in cow pastures, which means there is always productive breeding material available as no one cleans up pasture pats…For the past 16 years, North Carolina State University entomologists, Dr. Wes Watson and Steve Denning, have been researching IPM practices for pest fly control for commercial livestock and poultry operations…They have seen it all, testing at least 100’s of products…repellent on most and only a few animals with pesticide, to using electric traps, light traps, walk thru traps, feed thru products, ear tags, oilers, you name it…in 2006 as Steve was watching flies get scrapped off cows going thru a walk in trap, and then following the cow out the exit and getting right back on, he had an AH HA moment of “let’s see if we could vacuum up those little buggers”…Organic Valley heard about this unit and they sponsored a test, placing 6 units on North Carolina dairies in 2012…we made a trip to Raleigh, NC to see it. I knew from our efforts using Fly Predators to control Horn Flies that this little insect was a big deal. It took a lot of work as you had to put the Fly Predators in the pastures where the cows has just been and that only worked for those doing intensive grazing. Harrowing or running a screen drag over the pastures made a big difference too, but all those things took more time than most dairymen had. If this vac thing worked it would solve a horrible problem every grazier has…We agreed to license the technology from NC State and so began the redesign for production and optimization. This is the second unlikely alignment of the stars. I run a beneficial insect company, but I’m a mechanical engineer (ME) by schooling and in the 30 years prior had started a number of high tech companies…we refined the airflow on real animals. While the simulated cow got us very close to optimized performance, we actually were blowing too much air…”


Impaling Bed Bugs on Tiny Spikes (Leaf Hairs)

October 21, 2014

KIDNEY BEAN LEAF hairs, an ancient Balkan folk remedy to ameliorate bed bugs biting like vampires in the nighttime and wee morning hours, are in essence medieval warfare pikes barbarically impaling bed bugs resistant to 20th and 21st century synthetic pesticides. The resurrection of kidney bean leaves from Balkan folklore is a measure of human desperation, and an example of an IPM (Integrated Pest Management) strategy combining multiple weapons and tactics to fight this modern-day plague. According to The Journal of the Royal Society Interface, a modern offshoot of the one of the earliest medieval gatherings (mid-1600s) of natural philosophers, scientists and scientific craftsmen (instrument makers) into an official organization, those Balkan peasants knew a thing or two about fighting pestilence with “primitive” botanical remedies. Ultimately, bed bug-impaling bean hair “swords” or fabricated replicas will be combined in IPM strategies with other tactics, including ancient Ayurvedic Asian herbal remedies like neem tree oils (see previous blog).

You are not alone in being plagued by bed bugs: According to the journal Medical and Veterinary Entomology (Davies et al., 2012) there are “over 4 millennia of recorded narratives dating back to medieval European texts, classical Greek writings and the Jewish Talmud” and “archaeologists excavating a 3550-year-old workmen’s village at el-Amarna in Egypt found fossilized bed bug remains.” Plus bed bug “Females lay one or two eggs every day, and each female may lay 200–500 eggs in her lifetime, which may be 6 months or longer.” Modern heated buildings with lots of cracks, crevices and hiding places are even more comfortable for bed bugs than the ancient unheated buildings and caves of our ancestors.

The search for botanical remedies is perhaps equally ancient. Sir Francis Avery Jones, writing in the Journal Of The Royal Society Of Medicine (v. 89, Dec. 1996): “In the Stone Age the hunter-gatherers have learnt by hard experience…Over the eons they could have recognized plants which dulled pain, induced sleep, healed wounds, or poisoned animals or their enemies like wolfsbane…In Iraq there is a well-preserved grave of Neanderthal man, dated to some 60,000 years ago, with grains of flower pollen thickly scattered around the bones. The pollen came from eight different species still grown in Iraq today, some having recognized medicinal uses…Very early documents from China, Egypt, Sumaria and India describe the uses of anise, mustard, caraway, mint, saffron, thyme, cardamom, turmeric, cloves and pepper. The herbals reached their peak in the first century AD when the Greek physician Dioscorides assembled his vast De Materia Medica, recording the name, description, habit and medical use of some 600 plants.”

Bean leaves in comparison are a relatively modern bed bug botanical, a variant on the Tudor England practice of covering floors with pest-repellent (e.g. versus fleas, flies, plague, gaol fever/typhus) strewing herbs for their uplifting aromatic properties (e.g. rosemary, woodruff, various mints, box, lavender, santolina, hyssop, balm, cleavers, costmary, marjoram, meadowsweet, tansy). Queen Elizabeth’s use of meadowsweet leaves and flowers was described in The Herbal or Generall Historie of Plantes (1597) by John Gerard: “leaves and floures of meadowsweet farre excell all other strewing herbs for to deck up houses, for the smell makes the heart merrie and joyful and delights the senses.”

The Balkan remedy of bed bugs becoming entangled in hooked bean leaf hairs was written about by someone named Bogdandy in 1927 in the journal Naturwissenschaften and then again in 1943 by the USDA’s Henry Richardson in the Journal of Economic Entomology. According to a 2013 issue of The Journal of the Royal Society Interface, whose authors included Catherine Loudon of the University of California Irvine, who talked about the subject at the Entomological Society of America (ESA): “Historical reports describe the trapping of bed bugs in Balkan countries by leaves from bean plants strewn on the floor next to beds. During the night, bed bugs walking on the floor would accumulate on these bean leaves, which were collected and burned the following morning to exterminate the bed bugs.”

Fire, burning bean leaves that have “hooked” or “trapped” bed bugs, might be considered an extreme and specialized form of pest control heat treatment to be practiced with extreme caution. But compared to combating blood-sucking (vampirism) and werewolfism (Lycanthropy) in Hollywood B-movies, who’s to say. YouTube has videos showing bed bugs getting snagged by bean leaf hairs, and a simulation indicating that real bean leaves are still better than synthetic fabrics fabricated to mimick bean leaves. Kidney bean varieties are best for impaling passing bed bugs, and easy to use around a bed. But some lima bean varieties and small passion flower leaves also work, said Loudon. Interestingly, like computer chips, bean hairs that snag bed bugs best are toughened with silicon, unlike synthetic fabric hairs so far fabricated from substances like dental molding.

But given enough time, I would expect researchers in some dark Transylvanian lab in the Vampire District or in some light-splashed lab with surfboards along Frankenstein Row on the southern California coast to focus their scanning electron microscopes under high and low vacuums and eventually patent and reveal to the world nano-fabric silica hairs of a monstrous nature (to bed bugs) that can protectively surround sleepers and trap bed bugs before they bite. Or perhaps the genetic engineers will get there first with a carnivorous plant (the Venus Bed Bug Trap) for biocontrol. But if you’re keeping score, for most of human history, with some periods of remission, Team Bed Bug is still on top. In the meantime, pleasant dreams; and don’t let the bed bugs bite.


Silkworms for Medicine & Good Health

August 17, 2014

A SILKWORM A DAY may not keep the doctor away, but for some in South Korea silkworm proteins are the pathway towards reduced Alzheimer’s disease, less diabetes, less fatigue, stronger muscles and perhaps eventually gold and silver Olympic swimming medals; much the way ghost moth caterpillars naturally infected with cordyceps fungi are used by Chinese athletes and herbal medicine practitioners. Silkworm production dates back several thousand years, and likely came to the Korean Peninsula via China, where over a thousand years ago bolts of silk (30 ft/bolt; one day’s production by a skilled weaver) were equal to silver and gold as hard currencies. A director of the International Dunhuang Project (IDP) investigating ancient Silk Road links between Asia, the Middle East and Europe, Susan Whitfield, wrote in her book, Life Along the Silk Road, that distrust of promissory notes led to demands that horse buyers pay with bolts of silk. According to A Guide to Korean Cultural Heritage (Korean Information Service, 2001): “In Korea, ma (hemp) and ppong (mulberry) trees were cultivated; myeonpo (cotton cloth) and mapo (hemp cloth), as well as hapsa (twisted thread)” and jasu (embroidery) on silk date back well over a thousand years to a time when China imported fine silks from Korea.

Medically, biodegradable silkworm fibers are highly valued for their biocompatiblity (i.e. minimal immune response) when sewn with human tissues as sutures or stitches. Various formulations of silk are also useful in surgical or bioengineering operations such as growing new bones, nerves or blood vessels. “As has been documented over decades, silk protein exhibits high mechanical strength and flexibility, permeability to water and oxygen and can be made into nets, sponges or membranes, being easily handled, manipulated and sterilized…especially in tissue engineering for the generation of artificial bones or ligaments,” write researchers at China’s Nantong University investigating “silk-based or silk-coated materials for peripheral nerve repair.” The idea being to use silk “as scaffold material to prepare the tissue engineered nerve grafts for promoting peripheral nerve regeneration.” Silk scaffolds or blood vessels can also be designed to release various drugs (e.g. anti-coagulants, antimicrobials, anti-inflammatory agents).

Silks can also be naturally colored or made luminescent (fluorescent) by incorporating coloring agents into silkworm mulberry leaf diets: Hence, “novel silk-based material (that) not only maintains the superior properties of natural silk but can also be imbued with additional properties to perform sensing and monitoring functions” such as measuring changes in wound or tissue pH (i.e. acidity, alkalinity), says Dr. Han Mingyong, Senior Scientist at Singapore’s Institute of Materials Research and Engineering (IMRE). “The novel silk material can be used as fabrics in apparel, and furnishing. In biomaterials, it can add function to sutures, wound dressings, and tissue engineering scaffolds.” All this at “minimal cost and with little modification” of centuries-old standard silkworm production practices, but with real environmental benefits because: “The lengthy dyeing process and post-processing steps in conventional silk making are completely removed.”

Silkworm silk production involves getting the adult female silkworm moths, which are flightless and can no longer live in the wild after centuries of domestication, to lay eggs that hatch into caterpillars living on mulberry (some species prefer oak) leaves. When the silkworms pupate, they spin a silken cocoon which is dropped in boiling water so that the outer silk threads unravel and can be spun into the fibers of commerce. “According to legend, 5,000 years ago Chinese Empress Xi Ling-Shi discovered silk when a silkworm cocoon fell into her hot cup of tea,” says Ecoworldly.com. “She unraveled the strange cocoon and, wrapping the thread around her finger, soon realized what an exquisite cloth it would make…If this is true, the silkworm that haplessly fell into the empress’ cup on that fateful day met a fate very similar to that of modern day silkworms.” Being insects, which are animals, they are not vegetarian fare; those concerned with animal cruelty and animal rights activists need to consider that these silkworms are in essence a human-created species (almost a symbiosis) and unable to survive in the wild.

Beondegi (번데기), the boiled or steamed silkworm chrysalis, are served as a snack food on the streets in Korea, and University of Florida, Gainesville, entomology professor Nan-Yao Su, who donated termite trap (Sentricon) royalties to establish the Entomological Society of America’s (ESA) “Nan-Yao Su Award for Innovation and Creativity in Entomology,” told me of eating silkworm snacks as a student in Japan. Dr. Su was not that impressed, an opinion shared by a South Korean and her Brazilian guest’s “gag me with a spoon response” on Izumislife vlog on YouTube; though an older Korean lady in the background, presumably more well-versed in beondegi’s medicinal properties was gulping down the boiled insects sold by the street vendor like there was no tomorrow (increased longevity may indeed be a beondegi benefit). Evidently, silkworms or beondegi (번데기) are a cultivated taste. But Dr. Su, with Professor Marjorie Hoy as my witness, professed not to be a Trader Joe’s fan either. So, I kept to my plan to attend the Tuesday night ESA Annual Meeting Korean Young Entomologists networking meeting, which led off with drones for delivering biocontrol insects and concluded with a trio of researchers fresh off the plane from South Korea to talk (in Korean; with slides in English) about their impressive latest research on the medical benefits of eating silkworm proteins. I was impressed with the research, and spent the last few months reading the English language scientific literature on silkworms for medicine and good health. The result is an overly long blog, like those 3-hour articles I used to read in the New Yorker instead of going to sleep at night; but since the blog readers mainly come here via search engines looking for information on a topic, I figure overly long is okay.

The Korean Young Entomologists (KYE) Member Symposium led off with Yong-Lak Park’s “Shooting insects from the sky: Aerial delivery of natural enemies using aerospace engineering,” and finally sometime between 9 and 10 at night (some time changes from ESA Internet site) came the silkworm presentations by Eunyoung Ahn, Hyobin Seo, and Yiseol Kim from South Korea’s Kyungpook National University. Researchers Sungpil Ryu, Taedong Kwon, Yunghi Yeo, and Mihee Cho contributed to the work, but were not present. The researchers made the point that silkworm pupae had a higher protein and amino acid content than soybeans, and were high in desirable unsaturated fatty acids that lowered blood lipid levels (anti-obesity). In rat feeding trials, powdered, freeze-dried silkworm proteins increased skeletal muscle volume when swimming was the exercise. This has obvious appeal to body builders and others involved in exercise and training seeking to increase muscle mass, strength and energy. Specific amino acids (glutamine, branched-chain amino acids, cysteine) were singled out as most important to the immune systems of athletes. A combination of silkworm proteins and exercise had multiple beneficial effects: increased antioxidants; decreased MDA and inflammatory cytokines. Swimming plus silkworm pupae also improved fat metabolism, leading to lower blood lipid levels; so a combination of silkworm protein and exercise was deemed good for promoting weight loss or combating the worldwide epidemic of obesity caused by “excess nutrition” (e.g. the trend towards super-sized portions). Other research indicated benefits involving blood cholesterol, reduced fat synthesis and accumulation, and preventing liver cirrhosis in high-fat diets. Thus, silkworm pupae are potential weight-loss foods or food supplements.

The 25-volume Dong-eui-bo-gam (동의보감) (Mirror of Eastern Medicine), published in 1613 by the legendary Korean royal physician Heo Jun (허준), called silkworm pupa a natural healthy food and nontoxic remedy for diabetes, ischemic disease and “thinning.” Modern medical research indicates Heo Jun knew what he was talking about, and was actually a couple of centuries ahead of modern Western medicine. Our knowledge of the potential medical benefits of silkworms is rapidly expanding, particularly in South Korea, China and Japan; and to a lesser degree in India, where the silkworms are often a different species feeding on oak tree leaves. We have only scratched the surface of the medical benefits of silkworms in this blog.


The Mysteries of Colony Collapse

May 15, 2014

COLONY COLLAPSE DISORDER (CCD) of honey bees is one of the lingering mysteries of early 21st Century science in more ways than one: from its microbial, immune system and genetic components to an amorphous almost Orwellian terminology as imprecise and ambiguous as climate change (a slogan wide enough to encompass warming up, cooling down, and even staying the same temperature while the numbers fluctuate around the mean or average). The ambiguous language says both nothing and everything simultaneously, though underlying CCD is a quest for as yet unknown changes in insect rearing circumstances that will produce non-collapsing honey bee colonies. During the 19th century (1800s), a century marked by worldwide famines in the the old colonial empires and phylloxera-ravaged wine-grape vineyards collapsing in France, a revolution in modern medicine was being birthed in the mysteriously collapsing silkworm colonies. Fortunately for lovers of silk fabrics, fashion and textiles, 19th century silkworm farmers had the services of the real-life scientific Sherlock Holmes of the era, the famous French freelance scientist and sometime entomologist, Louis Pasteur.

Pasteur had a knack for solving applied problems like fermentation (beer, wine, vinegar) and silkworm colony collapse, and then using the results to develop broader theories like germ theory, which taught modern doctors to wash their hands and sterilize their instruments so as to stop spreading the germs that commonly killed their patients. How Pasteur almost single-handedly accomplished so much more than whole scientific institutes seemed able to do in the 20th century was the subject of an illuminating mid-20th century book, Louis Pasteur Free Lance of Science, by French-borne microbiologist Rene Dubos. “Toward the middle of the nineteenth century a mysterious disease began to attack the French silkworm nurseries,” wrote Dubos. “In 1853, silkworm eggs could no longer be produced in France, but had to be imported from Lombardy; then the disease spread to Italy, Spain and Austria. Dealers procuring eggs for the silkworm breeders had to go farther and farther east in an attempt to secure healthy products; but the disease followed them, invading in turn Greece, Turkey, the Caucasus–finally China and even Japan. By 1865, the silkworm industry was near ruin in France, and also, to a lesser degree, in the rest of Western Europe.”

“The first triumphs of microbiology in the control of epidemics came out of the genius and labors of two men, Agostino Bassi and Louis Pasteur, both of whom were untrained in medical or veterinary sciences, and both of whom first approached the problems of pathology by studying the diseases of silkworms,” wrote Dubos, who between World Wars I and II worked at the League of Nations’ Bureau of Agricultural Intelligence and Plant Diseases as an editor of the International Review of the Science and Practice of Agriculture. “A disease known as mal del segno was then causing extensive damage to the silkworm industry in Lombardy. Bassi demonstrated that the disease was infectious and could be transmitted by inoculation, by contact, and by infected food. He traced it to a parasitic fungus, called after him Botrytis bassiana (since renamed Beauveria bassiana, a widely used biocontrol agent)…An exact understanding…allowed Bassi to work out methods to prevent its spread through the silkworm nurseries. After twenty years of arduous labor, he published in 1836…Although unable to see the bacterial agents of disease because of blindness, Bassi envisioned from his studies on the mal del segno the bacteriological era which was to revolutionize medicine two decades after his death.”

Chemist Jean Baptiste Dumas, Pasteur’s mentor, prevailed upon the reluctant free lance scientist to head a mission of the French Ministry of Agriculture. “Although Pasteur knew nothing of silkworms or their diseases, he accepted the challenge,” wrote Dubos. “To Pasteur’s remark that he was totally unfamiliar with the subject, Dumas had replied one day: ‘So much the better! For ideas, you will have only those which shall come to you as a result of your observations!’”

A way of life was also at stake. As described in 19th century France by Emile Duclaux, Pasteur’s student and intimate collaborator (in Dubos’ book): “…the cocoons are put into a steam bath, to kill the chrysalids by heat. In this case, scarcely six weeks separate the time of egg-hatching from the time when the cocoons are carried to market, from the time the silk grower sows to the time when he reaps. As, in former times, the harvest was almost certain and quite lucrative, the Time of the Silkworm was a time of festival and of joy, in spite of the fatigues which it imposed, and, in gratitude, the mulberry tree had received the name of arbre d’or, from the populations who derived their livelihood from it.”

“The study of silkworm diseases constituted for Pasteur an initiation into the problem of infectious diseases,” wrote Dubos, who was influenced by the famous Russian soil microbiologist, Serge Winogradsky, who favored studying microbial interactions in natural environments rather than in pure laboratory cultures. “Instead of the accuracy of laboratory procedures he encountered the variability and unpredictability of behavior in animal life, for silkworms differ in their response to disease as do other animals. In the case of flacherie (a disease), for example, the time of death after infection might vary from 12 hours to 3 weeks, and some of the worms invariably escaped death…Time and time again, he discussed the matter of the influence of environmental factors on susceptibility, on the receptivity of the ‘terrain’ for the invading agent of disease. So deep was his concern with the physiological factors that condition infection that he once wrote, ‘If I had to undertake new studies on silkworms, I would investigate conditions for increasing their vigor, a problem of which one knows nothing. This would certainly lead to techniques for protecting them against accidental diseases.’”

“Usually, the public sees only the finished result of the scientific effort, but remains unaware of the atmosphere of confusion, tentative gropings, frustration and heart-breaking discouragement in which the scientist often labors while trying to extract, from the entrails of nature, the products and laws which appear so simple and orderly when they finally reach textbooks and newspapers,” wrote Dubos. “In many circumstances, he developed reproducible and practical techniques that in other hands failed, or gave such erratic results as to be considered worthless. His experimental achievements appear so unusual in their complete success that there has been a tendency to explain them away in the name of luck, but the explanation is in reality quite simple. Pasteur was a master experimenter with an uncanny sense of the details relevant to the success of his tests. It was the exacting conscience with which he respected the most minute details of his operations, and his intense concentration while at work, that gave him an apparently intuitive awareness of all the facts significant for the test, and permitted him always to duplicate his experimental conditions. In many cases, he lacked complete understanding of the reasons for the success of the procedures that he used, but always he knew how to make them work again, if they had once worked in his hands.”

Though famed for disproving the spontaneous generation of life, immunization via attenuated living vaccines and the germ theory of infectious disease: “Pasteur often emphasized the great importance of the environment, of nutrition, and of the physiological and even psychological state of the patient, in deciding the outcome of the infectious process,” wrote Dubos. “Had the opportunity come for him to undertake again the study of silkworm diseases, he once said, he would have liked to investigate the factors which favor the general robustness of the worms, and thereby increase their resistance to infectious disease…A logic of Pasteur’s life centered on physiological problems is just as plausible as that which resulted from the exclusive emphasis on the germ theory of contagious disease.”

The 21st century is riddled with insect colony conundrums and mysteries. For example, why among the social insects are honey bees plagued by Colony Collapse Disorder, while “Colony Expansion Disorder” prevails for other social insects in the USA. Rather than collapsing, USA colonies of Argentine ants are forming “super-colonies,” and red imported fire ant colonies are growing stronger by the day and annually expanding their North American geographic range; this despite being deliberately dosed with pesticides and attacked by biocontrol organisms (perhaps even more so than the beleaguered honey bees). And quite independently of mortgage rates and housing sales, Formosan subterranean termite colonies damaging billions of dollars of USA housing stock are happily munching away at both live trees and “dead-tree” wooden housing assets with little collective danger of colony collapse, though individual colonies come and go.

Perhaps beekeeping and crop pollination would be easier if Colony Collapse Disorder were an actual “disorder” as defined by the Diagnostic and Statistical Manual of Mental Disorders (DSM), and honey bees were endowed with sufficient consciousness and behaviors amenable to bee psychology or psychiatry.

The very real plight of honey bee colonies or hives is still in what Dubos would call the “atmosphere of confusion, tentative gropings, frustration.” At the most recent Entomological Society of America annual meeting, roughly a century and a half after silkworm colony collapse was eliminated by better more sanitary rearing practices, honey bee health was still puzzling. Honey bee colony loss in Virginia increased to 30% from 5-10% in recent years, possibly due to disease pathogens, pesticides and immune system suppression, say Virginia Tech researchers (e.g. Brenna Traver) studying glucose oxidase (GOX), an indicator of immunity in social insects. Honey bee social immunity is complex, involving factors as diverse as pheromones and grooming, and honey bee production of hydrogen peroxide (H2O2), which sterilizes food for the colony.

Nosema ceranae, a global gut pathogen, was seen all around the USA in 2007 at the same time as Colony Collapse Disorder. Black queen cell virus is another culprit, along with deformed wing virus, which is spread among honey bees by varroa mites. Then it is hard to overlook that over 120 different pesticides and their metabolites have been found in honey; including common beekeeper-applied pesticides such as coumaphos, fluvalinate, chlorothalonil and the antibiotic fumagillin. At the University of Puerto Rico, Gloria Dominguez-Bello is testing oxytetracycline and other commonly used antibiotics for their effects on honey bee microbes similar to those known to affect everything from obesity and brain function to organ transplants.

Those familiar with Pasteur’s entomological research on silkworm colony collapse in the 1800s would have experienced a sense of deja vu at the most recent Entomological Society of America meetings listening to Gloria DeGrandi-Hoffman, a research leader at the USDA-ARS Carl Hayden Bee Research Center in Tucson, Arizona. Nutrition, stress and pesticides may indeed be involved, but more focus is warranted for honey bee microbial health and gut microbes. Honey bee nutrition and microbiology is complicated by seasonal variations with changing food sources. According to DeGrandi-Hoffman, a lack of beneficial microbes may set honey bees up for infectious diseases like chalkbrood.

For example, pesticides used for Varroa mite control and potent beekeeping antibiotics like thymol and formic acid can affect the Lactobacillus microbes bees need for digestion and preservation of pollen as beebread, said DeGrandi-Hoffman. When bacterial plasmids found in high numbers in beebread are plated with the pathogen Aspergillus flavus, the pathogen rapidly loses virulence.

It is likely honey bees rely on beneficial microbes to protect from harmful pathogens, as honey bees have among the fewest immune system genes of any insect. Thus, when California almond growers spray fungicides, insecticides and miticides, a side effect could be fewer beneficial microbes in honey bee guts and in beebread. Thus, the honey bees would be less healthy and more susceptible to diseases like chalkbrood. Probiotic supplements designed to add beneficial microbes to honey bee diets are being tested in some California orchards. No doubt a familiar concept to those shopping for probiotic yogurts.


Whole Hog Into Debugging Michigan Apples

April 9, 2014

FROM TIME to TIME over the course of the centuries, agriculture seems to reinvent itself, and if anything modern agriculture based on the industrial model seems to be unconsciously integrating the higher animals back into the fruit tree groves, at least among those Michigan entomologists and farmers who appreciate the overlooked virtues of the hog as a faithful human servant at the beck and command of its handlers for hunting down pests that have become resistant to pesticides and difficult to control even with the latest pheromone mating disruption technologies. To those combating or hunting down feral pigs and wild boar disrupting native ecosystems and rooting up farm crops, turning pigs loose in apple, cherry, pear and other fruit tree orchards is likely to seem a heretical notion belonging to renegade rednecks or radical hippie farmers from the counterculture past stuck in a continuous time-warp loop with Spock and the characters from Star Trek.

One of the advantages of attending Entomological Society of America meetings is being able to follow themes like “livestock-crop reintegration,” which Ceres Trust Research Grants have been funding for Michigan State University entomologists like Krista Buehrer and Matthew Grieshop. Basically, organic hogs provide organic fruit orchards control of weeds and insect pests like plum curculio (Conotrachelus nenuphar), codling moth (Cydia pomonella) and Oriental fruit moth (Grapholita molesta). “The rotation of hogs through different pastures and orchards with supplemental nutrition sources” is also “a method of livestock-crop integration that avoids the problem of adhering to National Organic Policy (NOP) and Good Agricultural Practices (GAP) policies restricting the application of manure prior to harvest,” wrote Buehrer in “Graduate Student Final Report – Ceres Trust Research Grant.”

Rotating organic hogs through organic fruit orchards to clean out weeds and insect pests hidden inside fallen fruits, traces its roots to Charles Valentine Riley, who pioneered modern biological control in the orange orchards of Los Angeles, California. In his 1871 “Third Annual Report on the Noxious, Beneficial and other Insects of the State of Missouri,” Riley said that for apple curculio “the only real remedy is the destruction of infested fruit.” In 1890, writing in the Iowa Agricultural Experiment Station Bulletin, C.P. Gillette suggested grazing orchards with sheep or hogs to eat the insect-infested “windfallen fruit” on the orchard floor and thereby reduce pest populations.

From the 1800s into the Roaring Twenties, Iowa apple growers could not get rid of apple curculios by shaking the trees, cultivating the soil, pruning, or spraying arsenic pesticides, leading B.B. Fulton in 1925 and 1926 to test hog grazing on the “Apple Grove Orchards south of Mitchellville, Iowa.” Writing in the Journal of Agricultural Research in 1928, Fulton said: “The experiments with pasturing pigs were successful from a business standpoint. A cost account kept for the two years showed that this method of control was more than economical, for it actually netted a profit. In 1925 each pig returned a net profit of $10 above cost and feed and in 1926 a net profit of $7.65…five pigs per acre can, if properly handled, clean up the early dropped apples in an orchard and thus control the apple curculio. The critical time for such control, as shown by the seasonal history data, is from the middle of June until about the middle of July. Pigs weighing about 100 pounds are the best size for this purpose since they do not tramp down the low branches. They do not feed from the trees…”

Krista Buehrer told the 2012 ESA Annual meeting in Austin, Texas that weekly rotations (June-August) of grazing hogs eating dropped fruit (containing pests inside) on the orchard floor produced marketable organic hogs and reduced pests without harming earthworms or beneficial insects (e.g. lady beetles, lacewings, ground beetles, spiders, parasitoid wasps, tachinid flies, syrphid flies, dolichopodid flies, ants). ““There were 3 control plots and 3 hog grazed plots,” said Buehrer. “Grazed plots were bordered by electric fencing to prevent hogs from escaping. Twenty-four Berkshire hogs were rotated through each grazed plot twice. In 2012, they were in each plot for 1.5 weeks per rotation, for a total of 3 weeks per grazed plot. In 2013 they were in each plot for 1 week per rotation, for a total of 2 weeks per grazed plot. Hogs ranged from 50-90 lbs (23-41 kg) each.”

Hog grazing really only scratches the surface of changing fruit orchard floor management, which includes cover crops, living mulches, composts, etc. Perhaps it is more a case of everything old becoming new again, as grazing by cattle, sheep, goats, wild pigs and boar are considered part of traditional European agroforestry systems.


Bed Bug Herbal Remedies Work Well With Traps

July 15, 2013

THE NEEM TREE (Azadirachta indica), a medicinal mahogany tree (Meliaceae) native to arid broadleaf and scrub forests in Asia (e.g. India), has been used for over 4,000 years in Vedic medicine and has a heavy, durable wood useful for furniture and buildings because it is resistant to termites and fungi. Nonetheless, despite US EPA registration as a pesticide for crop and home use and a long legacy of neem seed oil use for cosmetics, shampoos, toothpastes and medicines in India, Ohio State University researcher Susan Jones could not find any households near her Columbus, Ohio, home willing to try neem in her bed bug control experiments.

“We had no study takers because of the regulatory requirements,” which scared off people, Jones told the Entomological Society of America (ESA) Annual Meeting. “You have to read page after page to residents about toxicity without being able to talk about the toxicity of alternative products” not as safe as neem. In October 2012, an empty house with bed bugs became available for research when its occupant opted to escape a bad bed bug infestation by leaving the infested home; and inadvertently transferred the infestation to their new home.

Jones monitored the empty house by placing in each room four (4) Verifi(TM) CO2 (carbon dioxide) traps and four (4) Climbup(R) Interceptor traps. Visual inspections revealed few bed bugs. On October 24, 2012, prior to neem treatments, 38 bed bugs were captured in Climbup(R) traps, indicating bed bug infestations only in the master bedroom and bed of the empty house. Eight Verifi(TM) traps captured 48 bed bugs in the dining room, guest room and master bedroom. As part of an IPM (integrated pest management) approach using multiple treatment tools: Electrical sockets were treated with MotherEarth(R) D diatomaceous earth; 3.67 gal (13.9 l) at a rate of 1 gal/250 ft2 (3.9 l/23 m2). Gorilla Tape(R) was used to seal around the doors and exclude bed bug movement from other rooms.

The neem seed oil product, Cirkil(TM) RTU, was sprayed in various places, including on books, backs of picture frames and cardboard boxes. Vials of the insecticide-susceptible Harlan bed bug strain were placed around the house for on-site neem seed oil vapor toxicity assays. Two days after spraying, bed bug mortality from neem seed oil vapors was highest in confined spaces; with 48% mortality in vials placed between the mattress and box spring, versus 28% mortality in open spaces. On Nov. 6, two weeks post-treatment, 123 dead bed bugs were vacuumed up and live bed bugs were detected in a second bedroom. Bed bug numbers were low because the monitoring traps were doing double duty, also providing population suppression by removing many bed bugs.

Herbal oils can also be combined with heat chambers at 50 C (122 F) or carbon dioxide (CO2) fumigation chambers to combat bed bugs. However, heat chambers are expensive, and CO2 fumigation with dry ice can pose handling difficulties and room air circulation issues, Dong-Hwan Choe of the University of California, Riverside, told the Entomological Society of America (ESA).

Herbal essential oils are useful against head lice, and in Choe’s native Korea clove oil from from the leaves and flower buds of clove plants (Syzygium aromaticum) is used in aromatherapy and as a medicine. Clove oil is rich in GRAS (Generally Recognized as Safe) compounds such as eugenol, beta-caryophyllene and methyl salicylate (sometimes called wintergreen oil), which are useful as vapors in control of insects and microbes. In dentistry, clove oil (eugenol) is widely used as an antiseptic and pain reliever.

Clove essential oils work faster in closed spaces or fumigation chambers (e.g. vials, Mason jars) than in open spaces. Essential oils are even slower to kill bed bugs when orally ingested. In experiments at varied temperatures, Choe placed 10 bed bugs in plastic vials with mesh tops. The vials were placed inside 900 ml (1.9 pint) Mason jars; filter paper treated with essential oils was placed on the underside of the Mason jar tops.

Herbal essential oils worked faster at higher temperatures. For example, methyl salicylate fumigant vapors provided 100% bed bug mortality in 30 hours at 26 C (79 F); 10 hours at 35 C (95 F); and 8 hours at 40 C (104 F). Eugenol vapors produced similar results; there were no synergistic or additive effects from combining eugenol and methyl salicylate. Choe told the ESA that his future trials will include: botanical oil granules; exposing bed bug-infested items to essential oil vapors; and checking for sublethal essential oil effects on parameters such as female bed bug reproduction.

Narinderpal Singh of Rutgers placed bed bugs on cotton fabric squares treated (half left untreated) with synthetic pesticide and herbal essential oil products: 1) Temprid(TM) SC, a mixture of imidacloprid and cyfluthrin (neonicotinoid and pyrethroid insecticides); 2) Ecoraider(TM) (Reneotech, North Bergen, NJ) contains FDA GRAS ingredients labeled as “made from extracts of multiple traditional herbs that have been used in Asia for hundreds of years for therapy and to repel insects;” 3) Demand(R) CS, which contains lambda-cyhalothrin (a pyrethroid insecticide); 4) Bed Bug Patrol(R) (Nature’s Innovation, Buford, FL), a mixture with the active ingredients listed as clove oil, peppermint oil and sodium lauryl sulfate.&&

Temprid(TM) SC and Demand(R) CS proved best on the cotton fabric test. In arena bioassays with Climbup(R)Interceptor traps, none of the four insecticides were repellent to bed bugs (i.e. repellency was less than 30%). Ecoraider(TM) was equal to Temprid(TM) SC and Demand(R) CS against the tough to kill bed bug eggs. Singh concluded that field tests of Ecoraider(TM) as a biopesticide were warranted.

Changlu Wang of Rutgers told the ESA that travelers might be protected from bed bug bites and bring home fewer bed bugs if protected by essential oil repellents, as well as by more traditional mosquito and tick repellents like DEET, permethrin and picaridin. Repellents are more convenient and less expensive than non-chemical alternatives such as sleeping under bed bug tents and bandaging yourself in a protective suit.

Isolongifolenone, an odorless sesquiterpene found in the South American Tauroniro tree (Humiria balsamifera), is among the botanicals being studied, as it can also be synthesized from turpentine oil and is as effective as DEET against mosquito and tick species. Bed bug arena tests involve putting a band of repellent around a table leg, with a Climbup(R)Interceptor trap below. If the bed bug falls into the trap, it is deemed to have been repelled from the surface above. In actual practice, the bed bug climbs up the surface and goes horizontal onto the treated surface and drops or falls off if the surface is repellent. Isolongifolenone starts losing its repellency after 3 hours; 5%-10% DEET works for about 9 hours. In arena tests with host cues, 25% DEET keeps surfaces repellent to bed bugs for 2 weeks. But isolongifolenone is considered safer, and Wang is testing higher rates in hopes of gettting a full day’s protection.


Pollinator-Friendly Lawns: Flowers or No Flowers?

April 28, 2013

TURF is a $25 BILLION USA INDUSTRY, said Nastaran Tofangsazi of the University of Florida (Apopka, FL), a sex pheromone researcher looking to complement biocontrols like beneficial Beauveria bassiana fungi and Steinernema carpocapsae nematodes to control the browning and uneven grass growth caused by tropical sod webworm (Herpetogramma phaeopteralis) in Florida’s $9 billion worth of turfgrass. Also at the Entomological Society of America (ESA) annual meeting, Auburn University’s R. Murphey Coy noted that the USA’s 164,000 km2 (63,320 square miles) of turf is the USA’s most irrigated crop. Turfgrass irrigation consumes 300% more water than corn; plus 4.5 pounds (2 kg) of nitrogen per 1,000 square feet (93 m2).

Alabama is among the top USA turfgrass-producing states, and Auburn University researchers are looking to reduce turfgrass water, nitrogen and iron inputs by colonizing grass seeds and roots with easy to apply sprays of plant growth promoting rhizobacteria (PGPR). Blends of PGPR species such as Bacillus firmis, Pseudomonas and Rhizobium in turfgrass and cotton induce systemic resistance to pestiferous Fusarium fungi and triple parasitic wasp biocontrol of the caterpillar larvae of moth pests like fall armyworm (Spodoptera frugiperda).

Not everyone is a fan of turfgrass lawns, and before the modern chemical era lawns were more like fragrant flowery meadows. “Agricultural experts and agribusiness are bound by the idea that even land that has lost its natural vitality can still produce crops with the addition of petroleum energy, agricultural chemicals, and water…considering this form of agriculture to be advanced,” wrote Japanese agriculturist and philosopher Masanobu Fukuoka in the book, Sowing Seeds in the Desert (edited by Larry Korn).

“When I suggested that it would be a good idea to plant fruit trees to line the streets in towns and cities and to grow vegetables instead of lawns and annual flowers, so that when the townspeople were taking a walk, they could pick and eat the fruit from the roadside, people were surprisingly enthusiastic,” said Fukuoka. “When I suggested that it would be good to scatter the seeds of clover and daikon on the existing lawns so that in two or three years the clover would overcome the lawn and the daikon would take root amid the ground cover, interestingly, it was the Asian people and Asian-Americans who said they would try it right away. Most Americans would just laugh and agree with the theory, but they were cautious about putting it into practice. The reason, I believe, is that it would challenge their adherence to ‘lawn’ culture. If they cannot overcome this prejudice, there will be a limit to the growth of family gardens in the United States.”

“It seems that the main goal in the life of the average American is to save money, live in the country in a big house surrounded by large trees, and enjoy a carefully manicured lawn,” wrote Fukuoka. “It would be a further source of pride to raise a few horses. Everywhere I went I preached the abolition of lawn culture, saying that it was an imitation green created for human beings at the expense of nature and was nothing more than a remnant of the arrogant aristocratic culture of Europe…Because residential lots are large in the United States, a family vegetable garden can provide for all the food needs of a typical family, if they are willing to do the work. In Japan, a residential lot about a quarter acre would be enough to allow near self-sufficiency and provide a healthy living environment, but I learned—to my envy—that in many suburban and rural areas of the United States, people are not allowed to build houses on small lots.”

On closer inspection, modern American lawns are more often a biodiverse mixture of turfgrass and flowering plants like clover and dandelions. Kentucky bluegrass lawns may be 30% white clover, which favors native pollinators like bumblebees. Clover and dandelion flowers attract honey bees, bumble bees, parasitic wasps that kill pests, hover flies (syrphids) that eat aphids, and carnivorous rove and ground beetles eating snails, slugs, caterpillars and other pests. Nonetheless, tons of herbicides go onto USA lawns to eradicate clover and dandelions as weeds, often as part of fertilizer and insecticide mixtures.

Turf biodiversity is all well and good, but only as long as the clover and dandelion flower nectar is pure and uncontaminated by pesticide cocktails. Lawns laden with clover and dandelion flowers provide bees and beneficial insects with “a big gulp of nectar,” the University of Kentucky’s Jonathan Larson told the ESA annual meeting in Knoxville, Tennessee. When those “big gulps of nectar” are laced with certain neonicotinoid pesticides, the effects can ripple through the ecological food chain.

When turfgrass pesticide labels say, ‘Don’t treat flower heads,’ “Follow the label to the letter of the law” to avoid poisoning pollinators, said Larson. Or get rid of the flowering plants in the lawn by mowing the turf before spraying. Or delay pesticide sprays until after clovers, dandelions and other lawn flowers have finished flowering. Clover control in lawns using herbicides is difficult, and usually not feasible, Larson told the ESA. Hence, mowing is the preferred strategy for removing flowering lawn weeds before spraying pesticides.

In enclosure experiments with tents confining bees in the turf, mowing the turf before pesticide treatment mitigated the problem, resulting in more bees and more honey. In 2012, bees were tented on clothianidin-treated turf for 6 days and then moved for 6 weeks to a Lexington, Kentucky, horse ranch with unsprayed turf. Clothianidin reduced the rate of bumble bee weight gain, but at the end of 6 weeks the bees were starting to catch-up. But overall, the 6-day pesticide exposure still resulted in reduced bumble bee weight gain, less foraging and reduced queen and hive reproduction several weeks later. Chlorantraniliprole, which has a different mode of action (muscular), did not produce these adverse effects. Larson also told the ESA that clothianidin, a widely used neonicotinoid turf pesticide, also reduces decomposers (detritivores) like soil-dwelling earthworms and springtails more than chlorantraniliprole.

Besides supporting more soil life, more biocontrol organisms, and healthier crops of pollinating bees, you get a healthier turfgrass lawn if you do not need pesticides and do not have to mow so often. “Mowing height is an easily manipulated cultural practice that can have an impact on ecological conditions,” Samantha Marksbury from the University of Kentucky, Lexington, told the ESA. “Taller grass usually supports a more diverse ecosystem and increases natural enemies. Increasing cutting height stimulated deeper roots, yielding a healthier turf with less need for insecticide. Higher mowing height decreases need for irrigation and the canopy prevents water loss.”

Taller turf (raised mowing height) also tends to be more robust and more tolerant of white grubs. Nevertheless, about 75% of turf is lush residential monocultures (mostly one grass species) that is heavily fertilized, dosed with chemical herbicides and frequently mowed, Emily Dobbs of the University of Kentucky, Lexington, told the ESA. However, the ecology of grass cutting or mowing gets quite complex and has seasonal variations. In May, turf with a low mowing height (2.5 inches; 6.4 cm) was hotter, drier, and had the most predatory ground beetles, rove beetles and spiders. Later in the season and Sept/Oct, turf with a higher mowing height (4 inches; 10.2 cm) was cooler, wetter, and had the most predators.

Historically, in the Middle Ages in England, going back many centuries (even before Chaucer) before the age of chemical farming and gardening, lawns were “flowery meads” with roses, violets, periwinkles, primroses, daisies, gillyflowers and other colorful, fragrant flowers interplanted right into the turf. The idea of planting a lawn with one species of grass made no sense, though a camomile lawn or plot came into being for infirmary gardens in England after 1265, as this medicinal aromatic plant helped other plants growing nearby in poor soils and grew faster the more it was trodden.

“There were no flower-beds of the sort familiar to us,” wrote Teresa McLean in her 1981 book, Medieval English Gardens. “The simplest type of flower garden was the flowery mead, wherein low-growing flowers were planted in turf lawns, sometimes walled, sometimes left open, to make a beautiful domestic meadow. The flowery mead was the locus amoenus of God’s beautiful world.”

“Trees were often planted in raised turf mounds, surrounded by wattle fences, which doubled as seats,” wrote McLean. “Medieval lawns, unlike modern ones, were luxuriously long, and full of flowers and herbs; they were fragrant carpets to be walked, danced, sat and lain upon. What modern lawn could find a poet to write about it as Chaucer wrote about the one in the Legend of Good Women?

Upon the small, soft, sweet grass,
That was with flowers sweet embroidered all,
Of such sweetness, and such odour overall…”


Medicinal Caterpillar Fungus High in Nepal’s Himalayan Mountains

December 27, 2012

CATERPILLAR FUNGI ARE not everybody’s finger food, though their beautifully-sculpted medicinal mushrooms are rich in fiber, amino acids, minerals and vitamins. The caterpillar fungus of commerce, Cordyceps sinensis, grows high in the Himalayan Mountains in the larvae (caterpillars) of equally high-altitude Asian ghost moths (genus Hepialus). An ancient medicine or tonic, caterpillar fungus is in reality part insect (mummified caterpillar) and part fungus; and perhaps a conundrum for vegetarians, who might have to take a pass on its medical benefits because of its animal kingdom (insect) component.

Cordyceps is an abundant resource of useful natural products with various biological activity, and it has been used extensively as a tonic and health supplement for subhealth patients, especially seniors, in China and other Asian countries,” write Kai Yue and colleagues at Sichuan Agricultural University in an article pre-published online in October 2012 in the Royal Pharmaceutical Society’s Journal of Pharmacy and Pharmacology.

For perhaps thousands of years (at least several hundred) in China and other Asian countries, “Cordyceps sinensis (Caterpillar fungus) has been used as a tonic for longevity, endurance, and vitality,” write Chinese Academy of Sciences researchers Zhenquan Liu et al. in an Open Access journal, Behavioral and Brain Functions. “Many studies have shown that Cordyceps sinensis modulates immune responses, inhibits tumor cell proliferation, enhances hepatic function, regulates insulin sensitivity” and modulates steroid production.

“Although Cordyceps sinensis is extensively used in Chinese medicine, it lacks scientific grounds for its efficacy,” write Liu et al. In other words, it has worked like magic for centuries; providing practical benefits, though the exact mechanisms of how it works are unknown or speculative. The Chinese researchers argue that even proponents of modern medicine objecting to traditional natural or folkloric medical treatments could benefit from studying the caterpillar fungus. Their argument is that the research results from studying the mechanisms of how the caterpillar fungus works to heal or prevent disease could also be used to develop more conventional medical or drug treatments.

Caterpillar fungus could be particularly useful for certain brain strokes, where modern medicine lacks effective drugs and treatments. ”The lack of effective and widely applicable pharmacological treatments for ischemic stroke patients may explain a growing interest in traditional medicines,” wrote Liu et al. An example is “self-medication or preventive medicine” to prevent cerebral ischemia. In this type of stroke, brain oxygen levels are too low; which can trigger a cascade of biological events leading to brain damage and death. Caterpillar fungus prevents or protects against this type of brain stroke (“ischemia-induced brain infarction”), presumably by inducing or modulating production of a steroid, 17beta-estradiol.

Cordyceps sinensis mushrooms growing out of golden caterpillar bodies are sometimes artfully and decoratively displayed in high-end Chinese herbal shops. Caterpillar fungus achieved some notoriety when it was revealed to be a dietary supplement for Chinese athletes bringing home gold and silver medals at the 2008 Beijing Olympics.

“In China, this fungus is usually called ‘Dong Chong Xia Cao,’ which means ‘Worm in winter and grass in summer,’” write Kai Yue and colleagues at Sichuan Agricultural University. “This insect parasitizing fungus lives primarily on the head of the larva of one particular species of moth, Hepialus armoricanus Oberthur (Lepidoptera), but is occasionally found growing on other moth species. Cordyceps was first introduced to Western society during the 17th century. In 1878 Saccardo, an Italian scholar, named Cordyceps derived from China officially as Cordyceps sinensis (Berk.) Sacc., and this nomenclature has been adopted up to the present day.”

At a Nepal Overseas Entomologists members symposium at the Entomological Society of America (ESA) annual meeting in Nov. 2012, at the Convention Center in Knoxville, Tennessee, Bhishma Subedi of the Asia Network for Sustainable Agriculture and Bioresources (ANSAB) screened a 20-30 minute documentary film as part of a talk titled, “Cordyceps sinensis a natural viagara(sic) from the mountains of Nepal.” Even the other Nepali entomologists in attendance learned something new, as the caterpillar fungus is found only in remote Himalayan Mountain locales; and it is not common knowledge, even in Nepal.

Known in Nepal by its Tibetan name, yarsagumba, caterpillar fungus is well-hidden; blending like a camouflaged black joss stick into black soils and grasses on slightly north-facing (5-10 degrees) Himalayan slopes 3,200 to 4,500 meters (10,500 to 14,800 ft) high. Yarsagumba lands are several days trek from anyplace where people normally live, and the ground is covered in snow 6 months of the year. But this is where temporary high-mountain camps must be set up for hunting the difficult-to-find caterpillar fungus.

Searching for the camouflaged black and debris-covered yarsagumba means crawling on hands and knees or bending over among short grasses and melted snow. Men search for yarsagumba and other medicinal herbs in the vicinity, while women stay behind and maintain the base camps. A certain Buddhist purity is maintained in yarsagumba lands; there is no alcohol, no tobacco and no shouting, loud voices or arguing. People pray, and the first yarsagumba found is offered to the Gods.

The beauty of the mountains belie the harshness of the climate and the difficulty of the life in search of yarsagumba; it’s a tough way to earn money in these remote mountains where economic opportunities are few. Storms can come at any time, and it is easy to fall down a steep cliff when climbing in the snow. A fall near a cliff edge can mean loss of limbs and frequently death. There are no second chances, no safety nets to catch you up here. Medical treatment is do-it-yourself, by necessity. Conventional medicine and doctors are many days distant. Widows are commonplace at all ages; and many subsistence families in Nepal have lost husbands, fathers, brothers and sons during the search for yarsagumba and medicinal herbs that may help others prevail against brain strokes and other maladies.

It takes seven cleanings with a toothbrush to remove all the debris and black soil, and make the black yarsagumba look like a proper insect, namely a golden caterpillar. The going price from the middlemen is 80,000 rupees per kilo; with 3,500 to 4,000 pieces of clean golden caterpillars per kilo. It takes five people a month to find a kilo. People are doing well to come out of the season with 60,000 rupees, before the expenses of the trek and weeks or months of camp costs. Recently, the Nepal government imposed a 20,000 rupee per kilo tax or royalty on the trade.

After being steamed and packaged, most of the yarsagumba eventually is exported and finds its way to the Chinese market. The yarsagumba trade is estimated at 2 tons annually. But in Nepal, since the government-imposed 20,000 rupee/kilo royalty or tax went into effect, it was like the yarsagumba harvest had become illegal for Nepal’s subsistence mountain people. Royalties were paid on only 3 kilos in a recent year. Perhaps there is a free market and tax lesson in all this. Or perhaps it is just part of the great wheel of life.


Doggone Birds (Fruit Protection)

September 13, 2012

Many bird species provide biocontrol by eating a wide range of insect pests, and are worth encouraging for controlling flies, mosquitoes, locusts, caterpillars, ticks, rodents and other pests around homes, forests, farms and gardens. Other bird species are considered pestiferous when feeding on our food plants, and can be repelled in various ways, including by loud noises, eyespot balloons, reflecting tape, scarecrows and scare devices, sensor networks and dogs.

Among the beneficial birds when they are not causing damage to utility poles or annoying people with their racket are woodpeckers. Personally, I like hearing woodpeckers working urban and forest trees, and was heartened to learn from Michigan State University’s Andrew Tluczek’s presentation to the Entomological Society of America (ESA) annual meeting that: “Woodpecker predation has caused up to 90% mortality of emerald ash borer (Agrilus planipennis) larvae in some sites.”

A 2006 tick control article in BioScience magazine devoted considerable discussion to birds for tick biocontrol. In Africa, birds known as oxpeckers (Buphagus spp.) provide biocontrol of ticks on mammals by consuming hundreds of adult ticks or thousands of nymphal ticks per day. Free-ranging guinea fowl experimentally tested around New York (USA) lawns reduced adult blacklegged tick numbers; but unfortunately the smaller nymph stage blacklegged ticks transmitting Lyme disease apparently were missed and not stopped very well.

The list of bird benefits for biocontrol, like barn owls for rodent biocontrol in Israel, Palestine, Malaysia and elsewhere could go on and on.

“Bird damage situations throughout the world are similar, involving many of the same crops and genera of birds,” wrote John W. De Grazio a few decades ago in the <em>Proceedings of the 8th Vertebrate Pest Conference. Seed-eating red-winged blackbirds, ring-necked pheasants, sparrows, crows, doves, parrots, munias, queleas, weavers and waterfowl are sometimes pests of corn, rice, wheat, sorghum, sunflowers, almonds, pecans, peanuts, etc. Starlings, sparrows, finches, grackles, robins, parakeets, etc. consume grapes, blueberries, and other fruit in yards, vineyards and orchards.

Dogs are used in pest control for sniffing out termites and bed bugs, and the natural proclivity of some dog breeds to chase birds can be harnessed to keep birds from destroying fruit in orchards and vineyards. In researching a grant proposal to travel to and write about Japan, which I failed miserably to qualify for, my Internet research for the proposal took me to the Japanese Journal of Farm Work Research. Being one of a select 4% of the USA population to have worked in agriculture, the journal title intrigued me enough to browse through several years of tables of contents, where I came across an intriguing article title: “Protection of Citrus From Bird Damage by a Dog.”

Not reading Japanese, I had to rely on the visual diagrams and English summary by researchers Hiromichi Ichinokiyama and Masami Takeuchi at the Kinan Fruits Tree Laboratory and Mie Prefectural Science and Technology Promotion Center:

“Effectiveness of a dog (Canus lupus familiaris) for protecting citrus fruits from bird damage was investigated using a citrus orchard (5.8 a in area) in the harvest season. In Experiment 1, a Border collie shepherd (male) was tied to a wire extended along one side of the square orchard to allow him to run along the inner side of the orchard. This watchdog system was effective in reducing fruit damage by birds (mainly brown-eared bulbul) only in the citrus tree row nearest to the dog runway.”

However, the researchers had better success letting the dog run free in the orchard:

“In Experiment 2, the orchard was enclosed with a tall chain-link fence and the same dog was allowed to move freely in the orchard. In this case, he persevered in chasing birds until they flew away from the orchard. This watchdog system effectively reduced bird damage to citrus fruits all over the orchard, resulting in an increase in crop yield…Further study is needed on the optimum number of dogs released per unit orchard area and the effectiveness of the watchdog system in case when this bird control system is spread to all orchards in the citrus-growing area.”

Like Richard Feynman’s Nontoxic Ant Ferry, dogs chasing birds away from trees laden with fruit or nuts is more a proof-of-concept awaiting further development than a fully developed technology you can order on the Internet.

Thank you to the organizations and people who created and are advancing the Internet, as even finding this sort of information would have been nearly impossible a few decades ago. Amazing how this high-tech infrastructure can advance low-tech solutions like the old-fashioned four-legged, tail-wagging dog as a bird-chaser in service of better fruit harvests.


Carbon Dioxide Gas Combats Bed Bugs

July 24, 2012

CARBON DIOXIDE GAS, an essential nutrient for photosynthesis and the human and animal food chain consuming green plants, can also play a key role in bed bug control. As an attractant, carbon dioxide (CO2) is useful for monitoring and trapping bed bugs and other vampire-like blood-suckers attracted to the gas, including ticks, mosquitoes, and assorted biting flies. Carbon dioxide gas, which has been used to fumigate everything from stored grain and food products to freight containers, museum collections, and hotel and motel rooms, can also be used to fumigate clothing, furnishings, books, electronics, and other bed bug-infested items.

Carbon, carbon dioxide, and the carbon cycle are integral to our very existence on planet Earth. “The carbon of the Earth comes in several forms,” writes University of Cambridge chemist John Emsley in his fascinating Oxford University Press book, Nature’s Building Blocks (An A-Z Guide to the Elements). “Most of what we eat –carbohydrates, fats, proteins and fibre – is made up of compounds of carbon…most ingested carbon compounds are oxidized to release the energy they contain, and then we breathe out the carbon as carbon dioxide. This joins the other carbon dioxide in the atmosphere, from where it will again be extracted by plants and become part of the carbon cycle of nature…The cycle rules the tempo of life on Earth and turns over 200 billion tonnes of carbon each year…In this way carbon is passed up the various food chains, with each recipient releasing some as carbon dioxide, until most carbon is back where it started.”

Does this mean that using carbon dioxide for bed bug control is environmentally acceptable, since it is kind of a “miracle of life” gas behind photosynthesis and plant life? Or is carbon dioxide really more the evil greenhouse or global-warming gas causing global climatic havoc and deserving of punishment via carbon taxes and elimination from the atmosphere via geological carbon sequestration (storage) schemes? Perhaps we should offset carbon dioxide releases for bed bug pest control with offsetting carbon dioxide injections into greenhouses, where elevated CO2 levels increase yields of greenhouse roses, tomatoes, cucumbers, peppers and other crops.

“Carbon is probably the most important element from an environmental point of view,” writes Emsley in Nature’s Building Blocks. “The Earth’s early atmosphere may have contained a lot of carbon dioxide and methane, but once life evolved that began to change. Today, there is very little of these gases and a lot of oxygen instead, thanks chiefly to the action of plants which convert carbon dioxide and water into carbohydrate and oxygen by photosynthesis. The Earth’s atmosphere contains an ever-increasing concentration of carbon dioxide and carbon monoxide, from fossil fuel burning, and of methane, from paddy fields and cows. Human contributions to these sources are still minor compared with natural sources: most carbon dioxide comes from plants, microbes and animals, while methane is given off by swamps, marshes and termite mounds.”

Obviously best to avoid bed bug infestations, and not have to think about remedies like carbon dioxide trapping or fumigations. Italian chemist Primo Levi makes the most persuasive literary argument: “Carbon dioxide, that is, the aerial form of carbon…this gas which constitutes the raw material of life, the permanent store upon which all that grows draws, and the ultimate destiny of all flesh, is not one of the principal components of air but rather a ridiculous remnant, an ‘impurity,’ thirty times less abundant than argon, which nobody even notices. The air contains 0.03 percent; if Italy was air, the only Italians fit to build life would be, for example, the 15,000 inhabitants of Milazzo in the province of Messina. This, on the human scale, is ironic acrobatics, a juggler’s trick, an incomprehensible display of omnipotence-arrogance, since from this ever renewed impurity of the air we come, we animals and we plants, and we the human species, with our four billion discordant opinions, our millenniums of history…”

Bed bugs concern themselves little with environmental correctness, and just tune into characteristics like the heat and carbon dioxide released by metabolizing warm-blooded meal hosts like humans, poultry, rodents, rabbits, etc. A flush from a CO2 cartridge is enough to flush bed bugs from their harborages or hiding places onto a bed in search of a meal. But more naturally, bed bugs follow CO2 gradients to locate live hosts for their blood meals.

“Carbon dioxide has been shown by several researchers to be the most effective attractant for bed bugs,” University of Florida-Gainesville entomologist Philip Koehler told a recent Entomological Society of America (ESA) annual meeting. Humans produce about 700 mg (0.02 oz) of CO2 per minute. “Thus, detectors with very slow CO2 releases cannot compete with human hosts,” said Koehler. “A rapid CO2 release is a better mimic to the human breathing pattern. Detectors with fast CO2 release captured about 4x more bed bugs than detectors with slow release.”

Trapping or monitoring bed bugs with CO2 is complicated by the fact that at different times in the life cycle bed bugs seek out hosts (releasing CO2) for blood meals when hungry; and then when well-fed, instead of CO2 bed bugs seek shelter in groups or cracks and crevices. So although CO2 is the better lure for hungry bed bugs, bed bugs that have fed have different needs and respond to different lures.

A commercial product, FMC’s Verifi(TM) trap, is a dual-action detector combining “fast CO2 generation with liquid kairomone and pheromone lures to attract both host-seeking bed bugs and aggregation-seeking bed bugs,” Koehler told the ESA. Carbon dioxide and the kairomone lure blood-seeking bed bugs into a pitfall part of the trap from which there is no escape. A pheromone lures harborage- or aggregation-seeking bed bugs seeking shelter in cracks and crevices into another part of the trap.

“An inexpensive detector that can be left in place and routinely serviced is needed to aid pest management professionals,” Ohio State University’s Susan Jones told the ESA. “Rutger’s do-it-yourself dry ice (frozen CO2) traps are a cheap and effective method for overnight surveys of potentially infested habitations.” An experiment in a 13-story high-rise apartment building in Columbus, Ohio compared (see You Tube video) 3 Verifi(TM) bed bug detectors per room with 1 CO2-generating dry ice trap per room and canine (dog) detection teams (2 dogs/room; same handler).

Verifi(TM) traps detected bed bugs in 11 of 17 infested rooms in the first 24 hours; and in 14 of 17 infested rooms within a week. Dry ice traps had similar efficacy. Dogs detected bed bugs in 19 rooms, including 3 rooms where neither visual inspections nor dry ice or Verifi(TM) traps detected anything. But the dogs were also not perfect, as each dog also missed 1 room rated positive for bed bugs. So the quest to capture bed bugs with carbon dioxide and other lures goes on.

Human ingenuity seems almost unlimited when it comes to traps. Carbon dioxide, heat and other attractants are all being tested with traps as varied as Susan McKnight Inc.’s Climbup bed bug trap and pitfall traps made from inverted dog bowls painted black on the outside. Rutgers’ Narinderpal Singh tested CO2, heat, and lures such as nonanol, octanol, 1-octen-3-ol, coriander, and spearmint with inverted dog bowl pitfall traps. CO2 had an additive effect with multiple-component lures in inverted dog bowl traps, and may be developed into an inexpensive monitoring system for detecting low levels of bed bugs. Trials with baited traps are continuing.

Both carbon dioxide and ozone show fumigant potential against bed bugs. Purdue University’s Kurt Saltzmann told the ESA of “Two devices capable of delivering ozone to laboratory fumigation chambers.” One device delivered a short exposure to high ozone levels, and the other long exposure to low ozone levels. “Preliminary experiments showed that adult male bed bugs were susceptible to relatively short periods of ozone exposure when high concentrations of ozone were used,” said Saltzmann. “100% mortality was achieved when bed bugs were exposed to 1800 ppm ozone for 150 minutes.” Low ozone fumigation is also being tested with 1-2% hydrogen peroxide for up to 72 hours.

Carbon dioxide (CO2) is used by libraries, museums, and others as an insect-killing fumigant. Indeed, dry ice (frozen CO2) to release CO2 gas is cheaper than washing and drying fabrics to kill bed bugs, Rutgers University’s Changlu Wang told the ESA. At an 80% concentration, CO2 kills all bed bug eggs in 24 hours (eggs are the toughest bed bug life stage to kill). A 50% CO2 concentration for 8 hours is sufficient to kill bed bug nymphs (immatures) and adults.

Wang’s CO2 fumigations involved filling Husky garbage bags 90% full of items such as mattress covers and fabrics, leaving little room for air. Then the bags were sealed with dry ice inside for several hours. Books, electronics, toys and other items damaged by heat treatments might benefit from the low temperatures created by dry ice treatments. However, for safety reasons Wang recommends wearing gloves and turning on fans for ventilation when opening many bags filled with carbon dioxide gas (fumigant).