Intergeneric (intersubtribe) hybridization between Moricandia arvensis and Brassica A and B genome species by ovary culture

Summary Intergeneric hybrids between Moricandia arvensis (C₃–C₄ intermediate species) and Brassica A and B genome species (B. campestris and B. nigra) were produced via ovary culture. When M. arvensis was used as a female parent, the hybrid embryo yield (0.25–0.45 embryo per pollination) was similar between two genomes, regardless of the male parent. The reciprocal hybrid using B. campestris as a female was also obtained, although yield of embryo was lower (0.02 embryo per pollination). On the other hand, no hybrids were obtained without the in vitro technique. As most hybrid embryos could not develop normal shoots, plants were regenerated by inducing shoots on the cultured hypocotyl. The hybrid nature of the regenerated plant was confirmed morphologically and cytogenetically. A certain amount of bivalents (2.52-2.71) in the hybrids indicated the existence of partial chromosome homology between two genera. The present results indicate that ovary culture is an effective technique for overcoming the crossing barrier between M. arvensis and Brassica cultivated species.