Evaluation of the potential for interspecific hybridization between Camelina sativa and related wild Brassicaceae in anticipation of field trials of GM camelina

Camelina (Camelina sativa (L.) Crantz) is a re-emergent oilseed crop that is also becoming important as a model for applied projects based on studies in Arabidopsis thaliana, since the two species are closely related members of the tribe Camelineae of the Brassicaeae. Since camelina can be transformed genetically by floral dip, genetically modified (GM) camelina is being created in many laboratories, and small-scale field trials are already being conducted in the US and Canada. Although camelina does not cross-fertilize Brassica crop species, such as oilseed rape, nothing was known about its ability to cross with other members of the tribe Camelineae, which in addition to arabidopsis includes the widespread weed, shepherd's purse (Capsella bursa-pastoris). We have tested the ability of camelina to cross with arabidopsis and C. bursa-pastoris, as well as with the more distantly related Cardamine hirsuta, tribe cardamineae. No seeds were produced in crosses with arabidopsis, and a few seeds were obtained in crosses with C. hirsuta, but the embryos aborted at an early stage of development. A few seeds were also obtained in crosses with C. bursa-pastoris, which germinated to produce plants of a phenotype intermediate to that of the parents, but the hybrids were both male and female sterile. Therefore, the likelihood of pollen-mediated gene flow from camelina to these related species is low.