GM crops not likely to become 'super-weeds'

The results of a long-term study reported in the 8 February Nature might allay fears that genetically modified (GM) crops, once released into the environment, could invade and dominate other habitats or cross-pollinate with non-crop plants.

Following a 10-year survey of four GM crops, Michael Crawley and colleagues, from Imperial College, London report that the particular GM crops studied did not survive well in the wild, and were not more likely to invade other habitats than their non-GM counterparts (Nature 2001, 409:682-683).

In 1990, fields located at 12 different sites in the UK, were planted with the GM crops available at the time — rape, maize, sugar beet and potato, each engineered to express resistance to herbicides or insects — alongside non-GM versions of the same crops. In no case was a GM crop found to be more invasive or persistent than its non-GM counterpart. Within four years, all crops ...