13 November 1998

GM combine spread

THE most likely route for GM oilseed rape to spread its key characteristics is through combines, not pollen, according to Rothamsted researcher Peter Lutman.

GM volunteers from seeds dropped in fresh fields from poorly cleaned machines will be much more significant than out-crossing from roadside plants or neighbouring crops, maintained Mr Lutman. In theory, a whole range of related crops and weeds can cross-pollinate with rape to absorb GM features, such as herbicide tolerance. In practice there are many hurdles, not least the relative size of the pollen cloud from competing crops, he explained. Both parents must also flower at the same time.

"The potential is there, but it is not very great."