MORE than 20 years ago, ecologists and even genetic engineers began to express concerns that genes from engineered crops could “escape” into populations of wild relatives, possibly with damaging consequences for the environment. Since then, dozens of research projects have attempted to discover whether there are natural barriers to prevent genes in conventionally bred crops from spreading to wild plants through cross-pollination.
There is now abundant evidence that natural hybridisation occurs readily when certain crops grow close to their wild relatives: rice and wild rice, sugar beet and sea beet, for example. Hybridisation is much more limited across other species…
