INHERITANCE OF MALE-STERILITY MUTATIONS INDUCED IN HAPLOID SORGHUM TISSUE-CULTURE

A high frequency of male sterile mutants regeneration was shown in cal lus cultures derived from leaves and panicles of haploid sorghum (Ms(c 1), A1 cytoplasm) and a spontaneous autodiploid obtained from this hap loid. The cultures derived from the embryos of this autodiploid yielde d significantly fewer mutants. Absolutely or partially male sterile mu tants appeared among the regenerants or in the progeny of fertile rege nerants. In the self-fertilized progenies of partially male sterile mu tants and in the hybrids of sterile mutants with autodiploid line (i.e , under one and the same nuclear genome) male sterility mutations were inherited as cytoplasmic. Non-Mendelian segregation of sterile, parti ally male sterile and fertile plants was observed in these progenies. Partially male sterile plants were characterized by somatic segregatio n of male sterility genetic factors. In test-crosses with some CMS Al fertility restorers, mutations were manifested as nuclear recessive wh ile with others as nuclear dominant. These differences are supposed to be the result of interaction of fertility restorer genes of these tes ters with the novel cytoplasm. Male sterility mutations accompanied wi th female sterility were inherited as nuclear recessives.