四川无融合生殖水稻(SAR-1)的初步研究

SAR-1是1988年春季在南繁育种材料中发现的新种质,该材料花粉高度不育而能自行结实,在隔离条件下,最高株系结实率达55.33％;经剪颖去雄、温水杀雄处理的颖花也能部分结实;经逐花取雄镜检,确认完全不育的颖花也能批量结实,最高结实率达41.80％。细胞胚胎学表明:SAR-1卵细胞不经受精,独自分裂形成胚,胚经正常发育,达到成熟;也观察到由子房壁细胞发育的不定胚,因此,可以推测SAR-1无融合生殖具多源性;未受精极核融合并分裂,发育成胚乳细胞,胚乳存在为胚的发育提供营养基础,胚乳自发形成,是SAR-1的一个十分显蔟的主要特征,SAR-1单性结实特性不仅能世代相传,也能转导到其它材料上。     

Initial Study on Sichuan Apomixis Rice (SAR-1)

SAR-1 is a new germplasm which was discovered in the breeding material of southern multiplication in spring, 1988. The material showing high sterility of pollens is able to set seeds spontaneously. Under isolation, the seed-setting highest rate may reach 55.33%. The florets emasculated by clipping spikelet and lukewarm water still set seeds at certain rates. The completely sterile florets, after being emasculated and checked under microscope one by one, still set seeds, and the highest setting rate is 41.80%. Cytoembryological research indicates that the egg of SAR-1, without fertilization, divides independently into an embryo, which follows the normal process to maturity. Adventitious embryos originate from ovary wall cells. Therefore, it is deduced that SAR-1 has multiple mechanisms of apomixis, and the unfertilized polar nuclei fuse and develop into endosperm cells. The endosperm provids the embryo with nutrient for development. The automatic formation of the endosperm is an obvious feature of SAR-1.