Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Beneficial insects, nematodes not harmed by genetically modified, insect-resistant crops

03.02.2014
A large body of literature has shown that genetically-modified plants that produce proteins from the bacterium Bacillus thuringiensis (Bt) to protect themselves from insect pests have little to no effect on a wide range of nontarget insects.

However, concerns about Bt crops still exist. Now two new studies using more exacting methods show that Bt crops have no negative effects on two beneficial insect predators or on a beneficial, entomopathogenic nematode.


This shows Geocoris punctipes feeding on an unidentified Homopteran.

Credit: Russ Ottens, University of Georgia, Bugwood.org

In an article in the February 2014 issue of Environmental Entomology, called "Using Resistant Prey Demonstrates that Bt Plants Producing Cry1Ac, Cry2Ab, and Cry1F Have No Negative Effects on Geocoris punctipes and Orius insidiosus," researchers used caterpillars that were known to be resistant to Bt proteins and fed them Bt maize and Bt cotton.

They then fed the caterpillars to two common, beneficial, predatory insects -- insidious flower bugs (Orius insidiosus), and big-eyed bugs (Geocoris punctipes) -- for two generations and compared them to another group of predators that consumed caterpillars fed on non-Bt plants.

The researchers found that the survival, development, adult mass, fecundity, and fertility of the insect predators in both groups were similar, regardless of whether they consumed caterpillars that fed on Bt plants or non-Bt plants.

"This research demonstrates that the current Bt proteins used in corn and cotton crops globally do not harm Geocoris punctipes or Orius insidious, two important insect predators that help suppress pest populations on corn, cotton, and many other crops," said Dr. Anthony Shelton, a professor of entomology at Cornell University and one of the co-authors. "By using caterpillars resistant to the Bt proteins in this study, we were able to remove any 'host quality effects' that might have led to spurious misinterpretation of the results. This work demonstrated that the caterpillars consumed the Bt proteins, and the predators consumed the Bt proteins when they fed on the caterpillars, but they did not suffer any harm even over multiple generations."

In a similar article appearing in the February 2014 issue of the Journal of Economic Entomology called "Tri-Trophic Studies Using Cry1Ac-Resistant Plutella xylostella Demonstrate No Adverse Effects of Cry1Ac on the Entomopathogenic Nematode, Heterorhabditis bacteriophora," Shelton and his colleagues used similar methods and found that an important nematode predator was not harmed when it ingested another Bt protein. For this study, resistant caterpillars were fed Bt broccoli and then exposed to Heterorhabditis bacteriophora, a beneficial nematode that preys on insects.

The researchers found that the virulence, reproductive potential, and time of emergence of the nematodes that consumed Bt-fed caterpillars were not significantly affected, compared to nematodes that did not ingest the Bt protein.

"This is the first report we are aware of in which a nematode predator has been tested in such detail against a Bt protein," Dr. Shelton said.

"Together, these two studies add to the scientific literature demonstrating that Bt plants can control targeted insect pests while not harming important natural enemies that help suppress pest species and maintain biodiversity in agricultural systems," Shelton added.

The Environmental Entomology article is avaliabe at: DOI: http://dx.doi.org/10.1603/EN13184

The Journal of Economic Entomology article is avaliabe at: DOI: http://dx.doi.org/10.1603/EC13310

Environmental Entomology and the Journal of Economic Entomology are 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.

Dr. Anthony Shelton | EurekAlert!
Further information:
http://www.entsoc.org
http://www.cornell.edu

More articles from Ecology, The Environment and Conservation:

nachricht Coorong Fish Hedge Their Bets for Survival
27.03.2015 | University of Adelaide

nachricht Greener Industry If Environmental Authorities Change Strategy
27.03.2015 | University of Gothenburg

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

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

Im Focus: Experiment Provides the Best Look Yet at 'Warm Dense Matter' at Cores of Giant Planets

In an experiment at the Department of Energy's SLAC National Accelerator Laboratory, scientists precisely measured the temperature and structure of aluminum as...

Im Focus: Energy-autonomous and wireless monitoring protects marine gearboxes

The IPH presents a solution at HANNOVER MESSE 2015 to make ship traffic more reliable while decreasing the maintenance costs at the same time. In cooperation with project partners, the research institute from Hannover, Germany, has developed a sensor system which continuously monitors the condition of the marine gearbox, thus preventing breakdowns. Special feature: the monitoring system works wirelessly and energy-autonomously. The required electrical power is generated where it is needed – directly at the sensor.

As well as cars need to be certified regularly (in Germany by the TÜV – Technical Inspection Association), ships need to be inspected – if the powertrain stops...

Im Focus: 3-D satellite, GPS earthquake maps isolate impacts in real time

Method produced by UI researcher could improve reaction time to deadly, expensive quakes

When an earthquake hits, the faster first responders can get to an impacted area, the more likely infrastructure--and lives--can be saved.

Im Focus: Atlantic Ocean overturning found to slow down already today

The Atlantic overturning is one of Earth’s most important heat transport systems, pumping warm water northwards and cold water southwards. Also known as the Gulf Stream system, it is responsible for the mild climate in northwestern Europe. 

Scientists now found evidence for a slowdown of the overturning – multiple lines of observation suggest that in recent decades, the current system has been...

Im Focus: Robot inspects concrete garage floors and bridge roadways for damage

Because they are regularly subjected to heavy vehicle traffic, emissions, moisture and salt, above- and underground parking garages, as well as bridges, frequently experience large areas of corrosion. Most inspection systems to date have only been capable of inspecting smaller surface areas.

From April 13 to April 17 at the Hannover Messe (hall 2, exhibit booth C16), engineers from the Fraunhofer Institute for Nondestructive Testing IZFP will be...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

World Conference On Regenerative Medicine 2015: Registration And Abstract Submission Now Open

25.03.2015 | Event News

University presidents from all over the world meet in Hamburg

19.03.2015 | Event News

10. CeBiTec Symposium zum Big Data-Problem

17.03.2015 | Event News

 
Latest News

Two Most Destructive Termite Species Forming Superswarms in South Florida

27.03.2015 | Agricultural and Forestry Science

ORNL-Led Team Demonstrates Desalination with Nanoporous Graphene Membrane

27.03.2015 | Materials Sciences

Coorong Fish Hedge Their Bets for Survival

27.03.2015 | Ecology, The Environment and Conservation

VideoLinks
B2B-VideoLinks
More VideoLinks >>>