Interspecific Buckwheat Hybrid between Fagopyrum esculentum andF. cymosum through Embryo Rescue

Abstract

In buckwheat, interspecific hybrids with perennial species could provide the opportunity to introgres new and usefulcharacters into annual species. An in vitro embryo rescue procedure, previously developed to produce interspecific hybrids of self-pollinating buckwheat, was used in this study. The comparative studies on embryo development in interspecific cross of F. escu-lentum F. cymosum indicated that incompatibility caused the embryo abortion. Pollen tube grew normally to reach micropyle in24 hours after pollination. Hybrid embryos at the early heart stage were disected 5 days after pollination (DAP) and cultured invitro on MS medium supplemented with zeatin (2.0 mg/l). When F. cymosum was used as a male parent, interspecific hybrid plantswere successfully obtained by culturing the embryos. Al of the hybrid plants grew normally and produced flowers. However,almost all of the hybrid plants were male-sterile. The new hybrid plants may be useful for the improvement of self-pollinatingbuckwheat in future, if sterility can be overcome.