Producing Fertile Somatic Hybrids

Summary

For introgression of alien genes into a cultivated genome it is necessary for the somatic hybrids to possess some fertility. The use of fluorescence-activated cell sorting for the production of large numbers of somatic hybrid plants should enable a realistic analysis in this respect. Various factors, including the degree of aneuploidy and homology between chromosomes, as well as the ploidy levels of the parental species, affect fertility in somatic hybrids. Irradiation of one of the parental species to inactivate the nucleus is known to facilitate the production of cybrid plants: this can result in the production of fertile interspecies cybrids possessing novel cytoplasmic features. Irradiation-induced chromosome breakage can also facilitate limited gene transfer and can result in the production of transgenic fertile plants. Encouragingly, triploid plants resulting from the fusion of haploid gametic protoplasts with diploid protoplasts have been shown to possess high levels of fertility.