分子标记辅助选择 Pi9基因改良 R288的稻瘟病抗性

摘要

To improve blast resistance of rice restorer line R288,an inner -gene functional marker Clon2 -1 was designed based on DNA sequence of the cloned broad -spectrum blast resistance gene Pi9,and molecular marker -assisted breed-ing was implemented.The main results were as the follows:Clon2 -1 is a co -dominant marker and showed obviously and stable polymorphism between Pi9 gene donor parent 75 -1 -127 and the receptor R288,and selection efficiency of Clon2-1 marker genotype for rice blast resistance phenotype reached 100%.The BC6 F3 population harboring Pi9 with R288 background was developed through consecutive backcross and self -pollination,and thereupon a resistant homozygous line R288 -Pi9 was bred.The hybrid produced by R288 -Pi9 and the photo -thermal sensitive genic male sterile line Peiai 64S,also showed high -level blast resistance.%根据已克隆的广谱持久抗瘟基因 Pi9的 DNA 序列设计功能标记 Clon2-1，通过分子标记辅助选择开展回交育种实践，定向改良水稻恢复系 R288的稻瘟病抗性。获得如下结果：Clon2-1为共显性标记，在 Pi9基因供体亲本75-1-127和受体亲本 R288之间多态性明显且稳定；Clon2-1标记基因型对稻瘟病抗性表型的选择效率达100％。通过分子标记辅助选择和连续回交自交，获得了含 Pi9基因的 BC6 F3群体，在此基础上筛选鉴定出1个高抗稻瘟病水稻新品系‘R288-Pi9’，用其与培矮64S 配组获得的杂交组合同样表现出高水平稻瘟病抗性。