Characterization of Interspecific Hybrids between Flowering Chinese Cabbage and Chinese Kale

Interspecific hybridization is considered to be an important driving force in the evolution, diversification, and formation of plant species. We selected one flowering Chinese cabbage variety and three Chinese kale varieties to make hybrids. Heterologous haploid offspring were obtained by embryo rescue and heterologous diploids were obtained by colchicine doubling. A total of 108 individuals of the F2, F3 and F4 generations from three parental combinations were investigated for field traits and SSR (simple sequence repeats) markers. The results showed trait separation and the appearance and disappearance of SSR bands in the hybrids, showing significant differences among parental combinations and among the different generations. This proved that the phenotypes of the initial generations of allopolyploids were not stable. This study not only enriches the genetic resources available for breeding flowering Chinese cabbage and Chinese kale, but lays a theoretical foundation for exploring the segregation of traits in distant hybrids and in different generations.