利用分子标记辅助选择聚合水稻抗病基因Pi-ta、Pi-b和Stv-b^i

Pyramiding Resistance Gene Pi-ta,Pi-b,and Stv-b～i by Marker-assisted Selection in Rice (Oryza sativa L.)

水稻稻瘟病和条纹叶枯病是长江中下游粳稻稻区两大主要病害,选育抗病品种是防治这两大病害最有效的方法。以同时含有稻瘟病抗病基因Pi-ta和Pi-b的武运粳8号,含有条纹叶枯病抗病基因Stv-bi的镇稻42为基因供体配置杂交组合。利用Pi-ta和Pi-b的基因标记和Stv-bi紧密连锁的分子标记对分离世代进行基因位点的检测,结合田间多代选育、抗性鉴定将3个抗病基因同时转育到高产品种中,选育出高产、优质、多抗水稻新品系74121。利用分子标记辅助选择,为选育多抗水稻新品种提供了一种简单、快捷的选择方法,同时也为水稻抗病育种提供了新的遗传资源。

The blast and stripe disease are two major diseases of rice in Yangtze River japonica cultivating area.Breeding resistant cultivars is the most effective way to prevent these two major diseases.Wuyujing 8,containing both Pi-ta and Pi-b,was crossed with Zhendao 42 which carried rice stripe disease resistance gene Stv-bi.Two gene-markers,Pita and Pib,and one SCAR marker tightly linked with Stv-bi were used for marker-assisted selection in each segregating generation.After the multi-generation breeding and identification of resistance,three resistance genes were put together finally.One new rice stable line,74121 was obtained which conferred good agronomic characteristics containing high-yield,good quality and multi-resistance.These results indicated that marker-assisted selection could not only be a simple and effective way but also provide genetic resources for breeding new rice multi-resistant varieties.