摘要
In order to identify the resistant gene of rice false smut in rice, a recombi- nant inbred line （RILs） population with 157 lines derived from an inter-subspecies cross of Daguandao/IR28 by the single seed descent method was used to detect quantitative trait loci （QTLs） conferring resistance to strain Pi-1 of rice false smut caused by Usti/aginoiclea virens （Cooke） Takahashi in 2012 and 2013. The disease rate indexes of the two parents and 157 RILs caused by the strain Pi-1 of rice false smut were scored and the QTLs for rice false smut resistance were detected accordingly by QTL Cartographer software. Seven QTLs controlling false smut re- sistance were detected on chromosomes 2, 7, 8, 11 and 12, respectively, with the phenotypic variance of 8.5%-17.2%. There were four QTLs detected in 2012 and 2013, respectively, and only one QTL was found in both two years, the phenotypic variation explained by this individual QTL was 13.5% and 17.2%, and the additive effects of this QTL contributed to the 9.9% and 14.3% decrease of disease index and therefore the disease resistance increased. The direction of the additive effects at five loci qFsr2a, qFsr8a, qFsr8b, qFsr11 and qFsr12 coincided with that predicted by phenotypes of the parents, and the IR28 alleles at these loci had positive effect against rice false smut while the negative effects were found in Daguandao alleles at qFsr2b and qFsr7. The qFsr11 should be useful in rice breeding for resistance to rice false smut in marker-assisted selection （MAS） program.
为了鉴定水稻对稻曲病的抗病基因,利用157个家系组成的大关稻（japonica）/IR28（indica）重组自交系（Recombinant inbred lines,RIL）群体,采用人工接种方法 ,以发病病情指数作为表型值。2012和2013年,接种鉴定亲本及RILs对水稻稻曲病致病菌株Pi-1的抗性。利用QTL Cartographer分析软件,对水稻抗Pi-1菌株基因进行检测分析。两年共检测到7个QTL,分别为位于第2、7、8、11和12染色体上的q Fsr2a、q Fsr2b、q Fsr7、q Fsr8a、q Fsr8b、q Fsr11、q Fsr12,单个位点的贡献率介于8.5%~17.2%之间。其中,2012年检测到q Fsr2a、q Fsr2b、q Fsr8a、q Fsr11等4个位点;2013年检测到q Fsr7、q Fsr8b、q Fsr11、q Fsr12等4个位点。q Fsr11在两年中均被检测到,对性状的解释率为13.5%和17.2%,作用效应使病情指数下降9.9%和14.3%,提高了抗病性。根据抗性位点加性效应方向,q Fsr2a、q Fsr8a、q Fsr8b、q Fsr11和q Fsr12等位点是来自于亲本IR28的增效等位基因,而位点q Fsr2b和q Fsr7的抗性效应方向相反,是来自于大关稻。稳定遗传的抗病位点q Fsr11及其紧密连锁的分子标记可以在分子标记辅助选择育种中得以应用。
基金
Supported by the National Natural Science Foundation of China(31071397)
the Agricultural Science and Technology Innovation Fund Project of Jiangsu Province(CX(15)1054)~~
