Abstract: To improve bacterial blight (BB) resistance of a wide compatibility restorer line 4183 of hybrid rice, Xa21 gene with the broad spectrum resistance to BB was introduced into the restorer line by using molecular marker-assisted selection successively in the process of back-crossing. The wide compatibility restorer line R4183(Xa21), with BB resistance was developed. It was similar in BB resistance to the donor IRBB21(carrying Xa21), maintained the good traits of the accepter of wide compatibility restorer line 4183. Problems and breeding strategies on improvement of BB resistance in hybrid rice were discussed.

Key words: rice, bacterial blight, molecular marker-assisted selection, wide compatibility, restorer line

摘要： 以IRBB21为Xa21基因供体,广亲和恢复系4183为受体，进行1次杂交并回交3次，逐代用分子标记检测手段，导入广谱抗白叶枯病基因Xa21,在保持广亲和恢复系4183优良经济性状的基础上，增强其抗白叶枯病的能力，育成抗白叶枯病的广亲和恢复系抗4183，其抗性达到了IRBB21的抗性水平，且保持了4183的广亲和性、恢复性及优良的经济性状。并就杂交水稻白叶枯病的抗性改良及育种对策进行了讨论。

关键词: 水稻, 白叶枯病, 分子标记辅助选择, 广亲和性