(Beyond Pesticides, April 11, 2024) Scientists are moving forward in testing an agroecological method of “push-pull” pest management (reducing the attractiveness of the target organism and luring pest insects towards a trap) to fight the Asian citrus psyllid (ACP) in Florida orange groves, as it spreads a plant disease known as the pathogenic bacteria huanglongbing (HLB), also known as citrus greening, which is deadly to citrus trees. The disease is spread by the pathogenic bacteria Candidatus Liberibacter asiaticus (CLas).  The chemical-intensive, or conventional, citrus industry is under intense pressure to find alternatives, as synthetic antibiotic use for this purpose has been successfully challenged in court. ACP is the carrier, or vector, for HLB, spreading it through the citrus groves and killing the trees. The chemical-intensive industry has focused on using antibiotics, which the environmental and public health community has rejected because of serious medical concerns associated with life-threatening bacterial resistance to antibiotics used to protect humans. A federal district court decision in December 2023 found illegal the U.S. Environmental Protection Agency’s (EPA) decision to register the antibiotic streptomycin in Florida citrus without adequate review of its impact on endangered species. The streptomycin lawsuit, filed in 2021 by a coalition of […]

New research highlights the beneficial effects of rose essential oil (REO) on tomato plants as a plant defense potentiator (a substance or treatment enhancing natural defense mechanisms against pests, diseases, and other stressors by activating the plant’s own defense responses) for organic agriculture and horticulture. As reported in the Journal of Agricultural and Food Chemistry, REO, particularly its component β-citronellol, activates defense genes in tomato plants, enhances their natural defense mechanisms, and dramatically reduces leaf damage by 45.5%. Additionally, REO attracts beneficial insects that prey on herbivore pests. This study, “Novel Potential of Rose Essential Oil as a Powerful Plant Defense Potentiator,” adds to a growing area of scientific literature on essential oil (EO), largely unexplored as plant defense potentiators. Beyond Pesticides advocates for accelerating the switch from chemical-intensive agriculture to organic agriculture, which remains the only viable solution, in the long run, to address today’s existential crises by prioritizing natural pest control methods, soil health, and biodiversity conservation to protect farmworkers and consumers from the detrimental effects of petrochemical pesticide exposure.     Study Methods and Results  The researchers applied highly diluted solutions of EOs to the soil of potted tomato plants and assessed the expression levels of defense genes in […]

(Beyond Pesticides, November 30, 2023) Scientists at Minami Kyushu University in Japan have made a groundbreaking discovery of a new biological control for a target insect. They have identified a virus in tobacco cutworms that kills males, creating all-female generations. The discovery was described in a recent issue of the Proceedings of the National Academies of Sciences and The New York Times as evidence that multiple viruses have evolved to kill male insects. This “male-killing” virus could be added to the growing attempts to control unwanted insects with biological, as distinguished from genetically engineered (GE) solutions. Efforts range from the introduction of natural predators, to radiation-based sterilization of insects, CRISPR-based genetic mutations, and other techniques. While the GE approach has run into controversy because of unanswered questions associated with their release into natural ecosystems, some approaches have also run into resistance problems. Nearly a decade ago, researchers found armyworm resistance to Bacillus thuringiensis (Bt)-incorporated genetically engineered (GE) maize in the southeastern region of the U.S., calling this evolution of insect resistance to a naturally occurring soil bacterium engineered into crops “a serious threat to the sustainability of this technology.” The general population knows to avoid eating raw eggs because the bacteria salmonella, […]

(Beyond Pesticides, September 26, 2023) In Ethiopia’s Bahir Dar, where Lake Tana feeds into the Blue Nile, a major hydroelectric power plant stands, serving as an emblem of the ecosystem services the river provides to over two million inhabitants. Yet ever since its first appearance in 2012, this crucial waterway has been under attack by one of the world’s most invasive species: the water hyacinth.   In America and Europe, where agrochemical giants such as Bayer and Syngenta are headquartered, such problems might quickly be remedied using herbicides. However, the prevailing ethos coming from the African continent is quite different. Dion Mostert, whose South African boat business has suffered due to the water hyacinths infestation, encapsulates this sentiment, saying he has considered herbicides but sees them as a temporary fix to a much larger challenge.  Instead of relying on temporary—and often harmful—agrochemical solutions, Ethiopia and other African countries are embracing holistic and sustainable solutions.   For instance, Lake Victoria–a water body shared by Kenya, Tanzania, and Uganda—suffered from a water hyacinth infestation in the 1990s. In response, scientists introduced two species of weevils known to be natural predators of the hyacinth: Neochetina bruchi and Neochetina eichhorniae. The initiative was extremely successful, […]

(Beyond Pesticides, July 12, 2023) A study by University of Delaware entomologist Thabu Mugala and colleagues finds that modifications to their farming methods can reduce slug damage when those changes also encourage natural slug predators, allowing farmers to avoid the endless cycle of pesticide dependency, pest resistance, genetically engineered crops, and synthetic fertilizers. With insects as the target for tens of millions of pounds of agricultural use, growers of the highest-production crops in the U.S., corn and soybeans, continue to find slugs to be a serious problem. Corn and soybean growers who have adopted no-till or conservation tillage and cover crops often think these practices worsen the problem by increasing moisture and decaying plant material in fields, which slugs love. But the cause-and-effect picture is more nuanced and requires strategies that nurture ecological balance. Slugs are the most damaging non-arthropod pest in no-till corn production in the U.S., and truly effective chemical deterrents do not exist at agricultural scale, as Beyond Pesticides noted here, although biological methods may be on the horizon, such as a parasitic nematode already used in Europe that shows promise. The most voracious natural slug hunters are ground beetles, but harvestmen (daddy longlegs), and wolf spiders […]

(Beyond Pesticides, June 6, 2023) Government agencies in Hawaii are making preparations to release a small parasitoid in an attempt to control infestations of coffee berry borer (CBB) in the state, according to a release published by the University of Hawaii.  “This biological control agent has the potential to make significant positive economic impacts in the Hawaiʻi coffee industry, and offers an environmentally safe way to manage CBB,” says Mark Wright, PhD, professor at UH. “The Hawaiʻi coffee industry is economically and culturally significant, and we hope that this work will improve the lives of many people associated with the industry.” The planned release comes at a time of increasing interest in nontoxic biological pest management as a means of reducing the harmful effects of industrially produced pesticides. As early as fall 2023, the U.S. Department of Agriculture’s Agriculture Research Service (USDA ARS) and UH’s Department of Plant and Environmental Protection Services plan to release thousands of parasitic wasps throughout coffee growing areas in Maui, O’ahu and the Big Island. The parasitoid in question is Phymastichus coffea, a wasp that lays its eggs in the abdomen of coffee berry borers. According to researchers, the wasp becomes attracted to the coffee […]

(Beyond Pesticides, November 16, 2022) Putting up with moderate pest levels can attract and maintain predators and parasitoids that provide important biological control services throughout the landscape, according to research recently published in Environmental Entomology. While scale insects can be a problem in urban areas, dropping sticky ‘honeydew’ on cars and structures, they also play a critical role in maintaining native populations of pest predators. Scientists at NC State University (NCSU) set out to understand just how important these pest populations are at maintaining their own natural enemies. To do so, researchers worked through a series of three hypotheses on the connection between urban trees, scale insects, and pest predators. Focus was first placed on investigating different oak species and comparing the number of predators between trees infested and not infested with scale. Twigs from willow oaks, sawtooth oaks, and overcup oaks were collected from scale infested and scale uninfested trees on the NCSU campus over the course of spring, and counted for their scale abundance. Then, through the summer, researchers used a sampling tool that effectively shook insects out of the tree and into a funnel collection. Unsurprisingly, scale infested oaks contain more scale insects. But these trees also […]

(Beyond Pesticides, June 29, 2022) A virus present in low levels in the United States is effective at managing populations of non-native fire ants, according to research. Although only focused on one particular fire ant, Solenopsis invicta (the red imported fire ant), the study published in the Journal of Invertebrate Pathology shows promise for gardeners, land managers, and the public looking to manage fire ants without the use of hazardous chemical insecticides. As climate change and global trade facilitate the spread of dangerous non-native species, there is a strong need for new and cutting edge approaches that target these pests without significant harm to public health or the surrounding environment. Prior testing by scientists involved in the current study had indicated that Solenopsis invicta virus 3 (SINV3), found sparsely throughout the U.S., was able to successfully infect and kill imported red fire ants in a laboratory setting. Scientists find that the virus modifies the behavior of worker ants, impeding their ability to either acquire or distribute food to larval ants. Worker neglect caused by the virus results in high larval mortality and degraded queen health, eventually leading to colony failure. Based on the promising laboratory data, scientists initiated a field […]

(Beyond Pesticides, June 8, 2022) A new biological agent to manage the destructive pest spotted wing drosophila (SWD) (Drosophila suzukii) is set to be released this month after approval was granted by the U.S. Department of Agriculture (USDA). Ganaspis brasiliensis, a parasitic wasp with a specific affinity for SWD, has the ability to significantly curtail the use of toxic pesticides otherwise employed to manage the pest. The move is an important step forward for biological pest management in the United States, an approach that has already added billions of benefits to agricultural economies, and has the potential to help farmers eliminate the regular use of hazardous pesticides. SWD is a small fruit fly originally from southeast Asia. In 2009, it was discovered on the U.S. West Coast and rapidly became a major pest, leading to significant crop loss estimated at over $700 million each year. The insect attacks nearly all soft bodied fruits, including blueberries, blackberries, raspberries, cherries, peaches, nectarines, apricots, grapes, and others. It has an apparent preference for blueberries, costing that industry alone $100 million per year. It lays its eggs inside of ripe fruit, which hatch into larvae and ruin the entire fruit as it feeds. Female […]

(Beyond Pesticides, April 26, 2022) Using pesticides to reduce the number of ticks in residential areas does not translate to lower rates of tick-borne disease in humans. This finding is the culmination of research overseen by scientists at the U.S. Centers for Disease Control and Prevention (CDC), which have been studying the effectiveness of pesticides to manage tick bites and tick borne-diseases for over a decade. While earlier research focused on direct pesticide applications to individual household lawns, the most recent publication, under early release in the Journal of Emerging Infectious Diseases, represented a broader, neighborhood-wide implementation of control measures. Yet in both instances, pesticide use did not play a role in reducing tick-borne disease. The studies are a stark warning for states and communities considering vector disease spray campaign for ticks in a similar manner to mosquito spraying. “The bottom line is that toxic pesticide use is not the answer to tick bites or tick-borne disease,” said Beyond Pesticides executive director Jay Feldman. “To manage ticks, we must embrace ecological solutions that work with natural processes and education campaigns emphasizing personal protection.” Researchers set out to test two methods of broad area tick control in 24 residential neighborhoods in […]

(Beyond Pesticides, March 24, 2022) A range of essential oils can provide high levels of larvicidal and adulticidal activity against a commonly found species of mosquito, according to research published last week in Scientific Reports. The use of essential oils in mosquito management has generally been limited to personal protection, with synthetic pesticides often the first choice for vector control activities. This research highlights the potential role of these natural compounds to replace hazardous synthetics in managing larval sources and killing adult mosquitoes under last-resort scenarios. The team of Egyptian-based scientists conducting the study purchased 32 different essential oils from a regional retailer in order to test them on both the larval and adult stages of Culex pipiens. C. pipiens, often referred to as the common house mosquito, is the most abundant mosquito in the Northern U.S., and is known to vector West Nile virus and Saint Louis encephalitis, among other diseases. Larval efficacy was tested on the fourth instar larvae of C. pipiens, delivered through a mixture of the essential oil, water, and the solvent Tween-20, which contains the surfactant Polysorbate-20, used to emulsify the mixture. All oils tested had some level of larvicidal activity (between 60-100%). Researchers classified […]

(Beyond Pesticides, March 16, 2022) Pest damaged plants release volatile chemical “scents” that alert other nearby plants of potential predators and give them time to prepare their defenses, according to research recently published in Plant Physiology by researchers at Tokyo University of Science. The findings have important implications for agriculture, including new practices that utilize this novel process. “The effective use of plants’ natural survival strategies in production systems will bring us closer to the realization of a sustainable society that simultaneously solves environmental and food problems,” says study coauthor Gen-ichiro Arimura, PhD. Budding research conducted since the turn of the century has discovered and confirmed that plants can communicate through specific volatile organic compounds (VOCs).  These compounds, referred to by researchers as “infochemicals,” can act as airborne signals that an herbivore danger is in the vicinity. Not only can plants within the same species communicate, there is evidence that plants will react to infochemicals produced by different species the other plant cannot produce, and may never have encountered. A recent experiment found, for instance, that soybean plants grown near mint are better able to withstand pest pressure by “eavesdropping” on VOCs produced by mint. Likewise, corn and tomato plants […]

(Beyond Pesticides, December 22, 2021) A promising new biocontrol agent for the tree of heaven (Ailanthus altissima)—considered an invasive species in the U.S. and Europe by some—was recently discovered by French-based scientists at the U.S. Department of Agriculture. The finding centers on a small mite of the Eriophyidae family, Aculus mosoniensis, which has been found to feed on tree of heaven. The finding is encouraging for the future management of this species in conjuction with balanced ecosystems. “In Europe, this Eriophyid mite is considered one of the most promising biological control agents of tree-of-heaven,” said Javid Kashefi, senior support scientist at the European Biological Control Laboratory (EBCL) in France. “This finding provides encouraging evidence that the geographic occurrence of this species is expanding in the continent.” Tree of heaven is a fast-growing deciduous tree native to Asia that has spread throughout Europe and North America. First introduced in the 1700s as a shade tree, it was appreciated for its quick growing ability and low propensity for insect damage, but quickly became problematic. Researchers identify five traits that warrant its classification as ‘invasive,’ including its ability to tolerate extreme environmental conditions, produce hundreds of alleopathic compounds (which harm, or inhibit the […]

(Beyond Pesticides, November 2, 2021) Cover crops create habitat that draw in pest predators and help mitigate crop injury, finds research published in the journals Agroecosystems and Biological Control from scientists at the University of Georgia. Expanded predator diversity can reduce pest pressure that drives conventional chemical farmers to apply toxic pesticides, and the authors of the study find the practice to be economically viable within these cropping systems. “There’s a motion of change going on where growers are thinking more about using natural systems instead of just using pesticides,” said co-author Jason Schmidt, PhD in a news release. “Producers must use all tools available to make a profit, so if they can promote beneficial insects in the system to aid in pest control,  fewer inputs are needed and that should lead to reduced costs of production. ” To determine how beneficial cover crops were to cotton production, researchers began with experimental crops established over two years in 2016 and 2017 in Georgia. Twelve cover crops plots were established with crimson clover and rye, while a plot not planted with cover crops was used as a control. Researchers planted the cover crop in early November after the previous cotton crop […]

(Beyond Pesticides, August 23, 2021) “Biopesticides”—widely regarded as an alternative to chemical pesticides and hence given a special status in regulation—need a better definition. “Biopesticide” is generally poorly understood, and defined differently by various entities and stakeholders. The term can be misleading and mixes contradictory approaches. It is troublesome when we continue to look for product replacements or substitutions for agricultural practices that are clearly ineffective, and in the process avoid the changes necessary to transition to organic practices, which represent the real, long-term solution to concerns among chemical-intensive farmers that they are losing pesticides in their arsenal, either to organism resistance or regulatory restrictions. The U.S. Environmental Protection Agency (EPA) uses the following definition for “biopesticides”: Substances that interfere with mating, such as insect sex pheromones, as well as various scented plant extracts that attract insect pests to traps (and synthetic analogs of such biochemicals); Microbial pesticides consisting of a microorganism (e.g., a bacterium, fungus, virus or protozoan) as the active ingredient; Plant-Incorporated-Protectants (PIPs), pesticidal substances that plants are genetically engineered to produce. Tell EPA it’s time to redefine “biopesticide.” It is deceptive and misleading. The definition should not include genetically modified organisms or synthetic analogs of naturally occurring […]

(Beyond Pesticides, May 26, 2021) Coffee leaf rust, caused by a fungus that can devastate fields of coffee plants, and the coffee industry of entire countries, was recently detected on the Hawaiian Islands for the first time. The U.S. Environmental Protection Agency (EPA) acted quickly to approve the emergency use of a synthetic fungicide, but new research conducted in the fungus’ home range shows the promise of a hyperparasite biocontrol. Caused by the fungus Hemileia vastatrix, coffee leaf rust was first documented in its home range of Africa in the 1860s. By the later part of that decade, it had spread to Sri Lanka, and destroyed the country’s monoculture coffee plantations, which were subsequently replaced with tea cultivation. The disease has now been found in every coffee producing country, but up until late last year, it had never been seen on the Hawaiian Islands. Thus, Hawaiian coffee farmers are rightly concerned about the disease. In response, EPA permitted the use of a product called Priaxor Xemium, a fungicide consisting of the active ingredients fluxapyroxad and pyraclostrobin, which has been linked to birth and developmental effects, and presents significant hazards to birds and aquatic organisms. “Hawai’i coffee growers now have an […]

(Beyond Pesticides, February 12, 2021) Being many decades down the path of chemical-intensive agriculture, growers and other land managers (and all the industries that influence them) have come largely to ignore the efficacy of healthy, functioning natural systems to maintain ecological equilibrium, i.e., not letting any one pest or disease proliferate. Recent research points to an example of such ecosystem efficacy. The study, by researchers in California and China, sought to evaluate whether increased population densities of fungi might be suppressing nematode populations in California production fields frequently planted with the cole crops (such as brussels sprouts and broccoli) they favor. The research finds that a diverse population of fungi in soils is highly likely to be effectively killing nematodes that threaten such crops. This is not the first time Beyond Pesticides has covered the potential of fungi as an effective control for agricultural pests. Thirty years ago, these nematodes were dealt with by application of soil fumigants and nematicides, because at sufficient population levels, the nematodes can destroy cole crops. During the following three decades, state-mandated monitoring showed that use of those chemical controls was diminishing and, by 2014, had been eliminated — even as yields rose. The co-authors […]

(Beyond Pesticides, September 29, 2020) While the green revolution is often heralded in conventional agriculture circles as the key agricultural innovation of the last century, new research finds that biological controls likely had a bigger beneficial impact on world crop production. The study, Ecological Pest Control Fortifies Agricultural Growth in Asia–Pacific Economies, published in Nature Ecology and Evolution, makes the case that the introduction of predators to manage non-native pest species was just as important as the introduction of new cereal grain varieties. “Our work constitutes an empirical demonstration of how insect biological control helped solidify the agrarian foundation of several Asia-Pacific economies and, in doing so, places biological control on an equal footing with other biological innovations such as Green Revolution germplasm,” said study co-author Michael Furlong, PhD, of the University of Queensland, Australia. The study, focusing in on the Asia-Pacific region between 1918-2018, relied primarily on the BIOCAT database, a record cataloging “classical biological control” introductions. Of 252 unique interventions reviewed within individual countries, pest predators established themselves in 96. Of those roughly 4 in 10 introductions that were able to maintain populations over the long term, 48% achieved full or partial pest control. The success of these […]

(Beyond Pesticides, March 18, 2020) Freshwater habitats are threatened now—more than ever—by the adverse effects of pesticide pollution, according to a report published in Scientific Reports by a collaborative research team from the Helmholtz Centre for Environmental Research (UFZ) and the Kenya-based International Centre of Insect Physiology and Ecology (ICIPE). Pesticide pollution, attributed to runoff from agricultural farms, indirectly increased the rate of the tropical disease schistosomiasis, which infects over 280 million people (2018). This research underlines the range of uncertainties that exist as a result of pesticide contamination, making it critically important that subtropical areas where this disease threat exists move toward organic and pesticide-free approaches.  Increased prevalence of this disease is devastating to socioeconomic development in affected regions, as life expectancy, employment rate, and gross domestic product (GDP) decreases. Schistosomiasis (snail fever), or bilharzia, is a tropical disease caused by parasitic flatworms (trematodes) in the genus Schistosoma and transmitted via freshwater snail (genus Biomphalaria) to its definitive human host. Freshwater snails act as a vector for schistosomiasis as they play a vital role in the lifecycle of the parasitic flatworm. Professor Matthias Liess (Ph.D.), Head of the Department of System Ecotoxicology at the UFZ, and his research team investigated pesticide pollution’s […]

(Beyond Pesticides, August 27, 2018) Beyond the visual and audial charms of some bird species, insect-eating birds play a significant role in controlling pests that can ruin crops or ravage forests. A meta-study by Martin Nyffeler, Ph.D. of the University of Basel in Switzerland finds that globally, birds annually consume 400-plus million metric tons of various insects, including moths, aphids, beetles, grasshoppers, crickets, and other arthropods (invertebrate organisms with exoskeletons, paired and jointed appendages, and segmented bodies, such as insects, crustaceans, and spiders). This research reviews 103 studies that examine the volume of insects consumed by various birds in seven of the world’s major biomes. In consuming such volumes of insects that can inflict damage on crops, trees, and other plants on which organisms may feed or otherwise depend, birds provide significant services to ecosystems, to denizens of habitats, and to human food system and economic interests; they also keep local ecosystems in balance. Threats to birds — and thus, to those ecosystem services — include those from pesticide use. Of the 10,700 known bird species distributed across the planet, more than 6,000 are primarily insectivorous. The study indicates that forest-dwelling birds consume the majority of insects (approximately 300 million metric […]

(Beyond Pesticides, July 5, 2018) With mosquito season in full swing throughout the U.S., land managers and abatement districts can be well served by employing biological controls in the form of fathead minnows (Pimephales promelas), according to research published earlier this year by scientists at the University of Waterloo in Ontario, Canada. In all but the most extreme conditions, these small fish, native throughout most of the continental United States, can provide effective control of mosquito larvae breeding in standing water. Beyond Pesticides encourages states and localities to focus primarily on larval control and public education as the best means to manage nuisance and disease-carrying mosquitoes, in contrast to adulticiding, the least effective means which allows 99.9% of a pesticide applied to contaminate the environment. At the close of Pollinator Week 2018, join us in urging Governors and state legislatures to ban the use of mosquito misters. To test the efficacy of fathead minnows to control mosquito populations, researchers stocked the fish in 10 water catchment basins in the central U.S. Over the course of three years, larval mosquito populations were monitored in these basins, as well as in six control basins that did not receive an influx of minnows. […]

(Beyond Pesticides, February 8, 2018) New trials are being launched in the United Kingdom (UK) to monitor fields that have long strips of wildflowers planted through croplands to boost natural predators and potentially reduce pesticide spraying. The large-scale trials are meant to determine how effective these strips can be as a tool for practitioners wishing to enhance biological pest control in the field. The field trials, carried out by the Centre for Ecology and Hydrology (CEH), are being conducted on 15 large arable farms in central and eastern England and would be monitored for five years. Until now, wildflower strips have been placed at the edge of fields as refuges. However, natural predators in these strips would be unable to access the center of large planted fields, and thereby unable to effectively target pests that are in the fields. In the new trials, six-meter wide strips of annual wild and cultivated plants – with 13 to 16 species – will be planted 100 meters apart so that predators will be able to attack aphids and other pests typically found in fields. The researchers at CEH’s ASSIST program (Achieving Sustainable Agricultural Systems) will determine whether in-field strips are feasible tools for […]

(Beyond Pesticides, January 4, 2018) Last month, the U.S. Environmental Protection Agency (EPA) released the preliminary ecological (non-pollinator) assessments for the neonicotinoids (neonics); clothianidin, thiamethoxam, dinotefuran, and the terrestrial ecological assessment for imidacloprid, finding that these pesticides pose both acute and chronic risks to aquatic life and birds. Treated seeds are identified as posing the highest dietary risks to birds, confirming previous research that neonics are highly hazardous not only to bees, but to birds, aquatic life, and other non-target organisms. Released December 15, 2017, EPA opened the public comment period for these assessments until February 20, 2018. Along with the risks identified in the assessments, the agency is specially requesting feedback on the benefits of continued use of the neonics in cotton and citrus crops identified in last year’s pollinator assessments as posing risks to honey bees. EPA states, “We believe early input from the public will be helpful in developing possible mitigation options that may be needed to address risks to bees.” This despite evidence of long-term systemic exposures to non-target organisms that support a phase-out of these pesticides. EPA believes that neonicotinoids are crucial for the management of Asian citrus psyllid, an invasive pest that causes citrus greening, […]