June 13, 2012

expert reaction to study of GM cotton, insecticide use and biodiversity

A report in Nature shows that in addition to reducing the need for pesticide use, transgenic crops that produce a bacterial insecticide can boost populations of beneficial pest-controlling predators. Evidence from the study of Bt Cotton suggests that this effect may spill over to neighbouring non-transgenic crops.

Professor Dale Sanders, Director of the John Innes Centre, said:

“This paper adds to evidence that GM crops can be eco-friendly. Through decreased use of insecticides, biodiversity is given a better chance of thriving. The research findings represent good news for everyone: sustainable agriculture can be managed through biotechnology to fulfil human requirements in terms of food yield and quality at the same time as delivering on environmental concerns such as biodiversity.”

Guy Poppy, Professor of Ecology and Principal Investigator (Insect/plant interactions), University of Southampton, said:

“Global food security will require us to sustainably intensify agriculture. Opponents of GM have argued this can’t be done through biotechnology, whereas this research challenges this view and demonstrates the wider benefits of using GM plants. By reducing the need for insecticides against caterpillars, insect biodiversity is increased and this is shown to have added benefits outside of the GM crop field. These BT crops are providing the ecosystem service of pest regulation within the Bt crop and to crops/plants in the wider environment – a true win-win which is required for the sustainable intensification of agriculture.”

Professor John Pickett from Rothamsted Research, leader of the work on a new GM wheat that repels aphids and attracts their predators and parasites, said:

“It is now nearly thirty years since the pioneering work of Jeff Schell and Marc Van Montagu led to the first transgenic plants producing insecticidal proteins from Bacillus thuringiensis (Bt).

“Many, including distinguished scientists, have looked for associated problems as the technology has been commercially developed throughout the world and, of course, we should always exercise caution in introducing new technologies. However, use of GM based Bt resistance to pest insects would not have advanced so dramatically without advantages, not least a reduction in use of insecticides against the target lepidopterous insect larvae.

“In this publication, we see clear evidence that these advantages extend to biological services at higher trophic levels and, specifically, to the predators of other pests such as aphids which are not controlled by Bt.

“This demonstration heralds the introduction of a new generation of GM crops that are engineered to manage beneficial insects, including predators and also parasitic wasps, and is the basis of our experiments, currently in the news, on transgenic wheat expressing genes responsible for producing the aphid alarm pheromone.”

‘Widespread adoption of Bt cotton and insecticide decrease promotes biocontrol services’ by Lu, Y. et al., published in Nature on Wednesday 13th June.