TRAITS such as herbicide resistance could spread from genetically modified
oilseed rape to its wild relatives if the crop were widely grown in Britain. The
first large-scale study of gene flow suggests that hybridisation between crops
and weeds is rare—but does occur.
Using satellite images covering 15 000 square kilometres of southern England,
Mike Wilkinson and his colleagues at the University of Reading identified fields
where normal oilseed rape or canola (Brassica napus) was being grown. A close
relative of oilseed rape, the wild turnip Brassica rapa, grows mostly along
river banks, so by looking at maps of waterways…
