Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Entomologists update definitions to tackle resistance to biotech crops and pesticides

03.03.2014

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!

Further reports about: EPA Entomological cotton crops farmers insects pesticides proteins resistance toxins transgenic

More articles from Agricultural and Forestry Science:

nachricht Plasma-zapping process could yield trans fat-free soybean oil product
02.12.2016 | Purdue University

nachricht New findings about the deformed wing virus, a major factor in honey bee colony mortality
11.11.2016 | Veterinärmedizinische Universität Wien

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

High-precision magnetic field sensing

05.12.2016 | Power and Electrical Engineering

Construction of practical quantum computers radically simplified

05.12.2016 | Information Technology

NASA's AIM observes early noctilucent ice clouds over Antarctica

05.12.2016 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>