Resistance to pesticides has now been recorded in nearly a thousand pest species, including more than 500 insects, 218 weeds, and 190 fungi that attack plants.
The recorded cases of resistance in insects, mites and other arthropods, which include resistance to multiple pesticides per species, more than doubled from 5,141 in 1990 to 11,254 in 2013. A first step in tackling this growing global problem is establishing a common vocabulary, because the current jumble of terms fosters confusion among scientists in academia, industry and government. To address this issue, five entomologists from the University of Arizona and Michigan State University updated definitions for 50 key terms related to resistance in a new article in the Journal of Economic Entomology (DOI: http://dx.doi.org/10.1603/EC13458).
"The lack of a modern glossary for resistance was recently brought to our attention by an initiative of the U.S. Environmental Protection Agency (EPA) seeking input on definitions of terms about resistance," said Dr. Mark Whalon, one of the co-authors from Michigan State University, who directs the online Arthropod Pesticide Resistance Database and who also serves as the Entomological Society of America's Liaison to the EPA Office of Pesticide Programs. "We provide a list of 50 key resistance terms and definitions aimed at facilitating understanding and management of resistance."
The authors favor definitions that promote proactive detection and management of resistance, such as resistance defined as "a genetically based decrease in susceptibility to a pesticide." They contrast this with an alternative definition used by some industry scientists that requires "repeated failure of a product to achieve the expected level of control," which generally occurs only after it's too late to respond most effectively.
The stakes are especially high for defining and managing insect resistance to corn and cotton plants genetically engineered to produce proteins from the bacterium Bacillus thuringiensis (Bt). These proteins kill some key pests, but are not toxic to people, wildlife, or even most insects. Organic growers have used Bt toxins in sprays for decades, and conventional farmers have widely adopted transgenic Bt crops since 1996. In 2013, Bt corn and Bt cotton were planted on 187 million acres worldwide and accounted for 75% of all cotton and 76% of all corn grown in the U.S.
Recognizing that resistance is not "all or none" and that intermediate levels of resistance can have a continuum of effects on pest control, the authors describe five categories of field-evolved resistance and use them to classify 13 cases of resistance to five Bt toxins in transgenic corn and cotton based on monitoring data from five continents for nine major pest species.
Emerging resistance of the western corn rootworm to Bt corn exemplifies the urgent need for well-defined resistance terms. The cost of this insidious beetle to U.S. corn growers has been estimated at one billion dollars annually. In 2003, to reduce costs and cut back on soil insecticides, U.S. farmers began planting Bt corn that kills rootworms.
"The first evidence of rootworm resistance to Bt corn was discovered in Iowa in 2009," said Dr. Bruce Tabashnik, the study's lead author and head of the entomology department at the University of Arizona. "Nearly five years later, the resistance has spread but decisive regulatory action by the EPA is still stalled, in part because an effective definition of resistance is lacking in this case."
Although some scientists have expressed concern that reports of pest resistance to Bt crops provide 'ammunition' to anti-biotech activists, Tabashnik said "Pests are remarkably adaptable. They usually evolve resistance to any tactic that's used repeatedly to control them, so this problem is not limited to transgenic crops." Noting that insects have been evolving resistance to natural plant defenses for millions of years and that this year marks the 100th anniversary of the first reported case of insecticide resistance, he concludes, "Finding ways to delay resistance is a never-ending challenge with any pest management approach."
The full article can be accessed at http://dx.doi.org/10.1603/EC13458
The Journal of Economic Entomology is published by the Entomological Society of America, the largest organization in the world serving the professional and scientific needs of entomologists and people in related disciplines. Founded in 1889, ESA today has more than 6,500 members affiliated with educational institutions, health agencies, private industry, and government. Members are researchers, teachers, extension service personnel, administrators, marketing representatives, research technicians, consultants, students, and hobbyists. For more information, visit http://www.entsoc.org.
Dr. Bruce Tabashnik | EurekAlert!
Farming with forests
23.09.2016 | University of Illinois College of Agricultural, Consumer and Environmental Sciences (ACES)
Ecological intensification of agriculture
09.09.2016 | Julius-Maximilians-Universität Würzburg
The Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP has been developing various applications for OLED microdisplays based on organic semiconductors. By integrating the capabilities of an image sensor directly into the microdisplay, eye movements can be recorded by the smart glasses and utilized for guidance and control functions, as one example. The new design will be debuted at Augmented World Expo Europe (AWE) in Berlin at Booth B25, October 18th – 19th.
“Augmented-reality” and “wearables” have become terms we encounter almost daily. Both can make daily life a little simpler and provide valuable assistance for...
With the help of artificial intelligence, chemists from the University of Basel in Switzerland have computed the characteristics of about two million crystals made up of four chemical elements. The researchers were able to identify 90 previously unknown thermodynamically stable crystals that can be regarded as new materials. They report on their findings in the scientific journal Physical Review Letters.
Elpasolite is a glassy, transparent, shiny and soft mineral with a cubic crystal structure. First discovered in El Paso County (Colorado, USA), it can also be...
For the first time, Fraunhofer IKTS shows additively manufactured hardmetal tools at WorldPM 2016 in Hamburg. Mechanical, chemical as well as a high heat resistance and extreme hardness are required from tools that are used in mechanical and automotive engineering or in plastics and building materials industry. Researchers at the Fraunhofer Institute for Ceramic Technologies and Systems IKTS in Dresden managed the production of complex hardmetal tools via 3D printing in a quality that are in no way inferior to conventionally produced high-performance tools.
Fraunhofer IKTS counts decades of proven expertise in the development of hardmetals. To date, reliable cutting, drilling, pressing and stamping tools made of...
At AKL’16, the International Laser Technology Congress held in May this year, interest in the topic of process control was greater than expected. Appropriately, the event was also used to launch the Industry Working Group for Process Control in Laser Material Processing. The group provides a forum for representatives from industry and research to initiate pre-competitive projects and discuss issues such as standards, potential cost savings and feasibility.
In the age of industry 4.0, laser technology is firmly established within manufacturing. A wide variety of laser techniques – from USP ablation and additive...
Every three years, the plastics industry gathers at K, the international trade fair for plastics and rubber in Düsseldorf. The Fraunhofer Institute for Laser Technology ILT will also be attending again and presenting many innovative technologies, such as for joining plastics and metals using ultrashort pulse lasers. From October 19 to 26, you can find the Fraunhofer ILT at the joint Fraunhofer booth SC01 in Hall 7.
K is the world’s largest trade fair for the plastics and rubber industry. As in previous years, the organizers are expecting 3,000 exhibitors and more than...
23.09.2016 | Event News
20.09.2016 | Event News
16.09.2016 | Event News
26.09.2016 | Materials Sciences
26.09.2016 | Materials Sciences
26.09.2016 | Materials Sciences