Oilseed Rape: Co‐existence and Gene Flow from Wild Species

Abstract

Abstract Oilseed rape ( Brassica napus ) is partly outcrossing. This gene flow between oilseed rape and the environment may have consequences such as effects on purity and quality of the oilseed rape harvest and abundance of wild relatives. The rape pollen is transferred by insects and wind, and seeds are spilled before and after harvest. Hybridization between different oilseed rape fields and between fields and volunteers will take place. Especially in relation to dispersal of transgenes from GM oilseed rape, this intraspecific gene flow is unwanted. Impurities from unintended mixture of seeds of different varieties during harvest or transportation is another source of adventitious presence. To limit dispersal of genes through pollen and seed, a number of measures could be taken. Among the most effective are physical separation of fields, effective control of volunteers, testing the purity of the certified seed, and cleaning of agricultural machinery. Hybridization between oilseed rape and wild or cultivated relatives can also occur. This interspecific gene transfer is most frequent between oilseed rape and the species B. rapa . After the formation of hybrids between the crop and the relative, survival of the hybrids in the ecosystem will depend on the hybrid‐fitness. Wild species that receive transgenes from GM oilseed rape may experience decrease as well as increase in their abundance depending on the selection for the transgene.