SCIENCE IN THE NEWS DAILY
GM Crops Good for Environment, Study Finds
from the Guardian (UK)
Crops genetically modified to poison pests can deliver major environmental benefits, according to a landmark study spanning two decades and 1.5 million square kilometres. The benefits extended to non-GM crops grown in neighbouring fields, researchers found.
Plants engineered to produce a bacterial toxin lethal to some insects but harmless to people were grown in over 66 million hectares around the world in 2011. So-called Bt cotton is one type and now makes up 95% of the vast plantations in China. Since its introduction there in 1997, pesticide use has halved and the new study showed this led to a doubling of natural insect predators such as ladybirds, lacewings and spiders. These decimated pests not targeted by the Bt cotton, not only in the cotton fields, but also in conventional corn, soybean and peanut fields in the region.
"Insecticide use usually kills the natural enemies of pests and weakens the biocontrol services that they provide," said Professor Kongming Wu at the Chinese Academy of Agricultural Sciences in Beijing, who led the research team. "Transgenic crops reduce insecticide use and promote the population increase of natural enemies. Therefore, we think that this is a general principle."