Somatic hybrids between Arabidopsis thaliana and cabbage (Brassica oleracea L.) with all chromosomes derived from A-thaliana and low levels of fertile seed

We obtained somatic hybrids between Arabidopsis thaliana Columbia, and a cabbage variety, 'Chusei Succession' (Brassica oleracea L.), in addition to our previous success using the cabbage variety 'Fujiwase'. All hybrids of the two combinations possessed the chloroplast genome of cabbage, while the mitochondrial genome was recombined. PCR primers specific to each of the five chromosomes of A. thaliana were designed and used to analyze the hybrids. It was found that the hybrids had all five chromosomes of A. thaliana. Somatic hybrids between Columbia and 'Chusei Succession' flowered and showed extremely low pollen fertility, producing no seeds by spontaneous self-fertilization, whereas seeds were obtained by crosses between somatic hybrids and three cultivars of B. oleracea. The seeds could be useful materials for the transfer of genes of A. thaliana to cabbage and to establish cabbage lines with novel mitochondrial genomes.