分子标记辅助选择改良宁恢8号的条纹叶枯病抗性

Improving Resistance to Rice Stripe Disease of Restorer Line Ninghui 8 by Molecular Marker-Assistant Selection

为改良宁恢8号的条纹叶枯病抗性,以含条纹叶枯病抗性基因Stv-bi的品种关东194为供体,通过杂交、回交,利用与条纹叶枯病抗性基因Stv-bi和恢复基因Rf1a共分离的分子标记进行辅助选择,将条纹叶枯病抗性基因Stv-bi导入宁恢8号,结合田间抗性和性状鉴定,至BC3F3育成10个条纹叶枯病抗性显著提高、农艺性状优良的改良系。选择其中4个综合性状较优的株系分别与不育系A25、A19和A70进行配组鉴定。结果表明,改良系-2所配组合的综合性状明显优于对照宁恢8号的相应组合。

A molecular marker assisted selection （MAS） strategy was used to improve the resistance to rice stripe disease of Ninghui 8, the restorer line of japonica hybrid 86 you 8, by advanced backcross with Ninghui 8 as the recurrent parent and Kanto 194 as the donor of the rice stripe disease resistant gene. Markers tightly linked with Stv-b~ and Rfla genes were used for selecting the two genes of the ability to recovery the sterility and to resistant the stripe disease, respectively. After identification of the rice stripe disease resistance and investigation of some agronomic traits, 10 resistance improved lines with similar characteristics as Ninghui 8 were developed in BCa Fa generation, and 4 lines with excellent characteristics were selected to cross with male-sterile lines A25, A19 and A70, respectively. The results indicated that comprehensive characters of hybrid combinations from improved line-2 were significantly better than those from Ninghui 8.