利用Pi9基因分子标记辅助选择培育抗稻瘟病水稻新品系

Breeding New Rice Line with Blast Resistance by Molecular Marker-assisted Selection of the Pi9 Gene

利用广谱持久抗瘟基因Pi9的内含子序列设计特异功能标记Ins2-1,通过分子标记辅助选择和连续回交育种,改良早籼稻1701的稻瘟病抗性。结果表明:Ins2-1是一个显性分子标记,在Pi9基因供体亲本75-1-127和受体亲本1701之间多态性明显且稳定;Ins2-1标记基因型对稻瘟病抗性表型的选择效率为100%;通过连续回交和自交,获得了含Pi9基因且遗传背景接近受体亲本的BC6F2群体;通过对BC6F3株系标记基因型和室内接种表型鉴定,筛选出了一个抗病纯系"抗瘟1701"。

To improve blast resistance of the early season indica rice line 1701, a dominant functional DNA marker, Ins2-1, was developed based on the intron sequence of the broad-spectrum blast resistance gene Pi9 and marker-assisted selection breeding practice was implemented in this study. The main results were as follows： Ins2-1 showed stable polymotphism be- tween 1701 and 75-1-127,the Pi9 donor, and the selection efficiency of the marker genotype for blast resistance phenotype was 100%. A BC6F2 population,harboring the Pi9 gene and consecutive backcrossing and bagged-pollination,and a blast possessing receptor＇ s genomic background,was developed by resistant rice pure line, named resistant 1701 ,was identified from the BC6 F3 families by genotypic and phenotypic analyses, these work paved a way for breeding elite blast resistant rice varieties or hybrids.