利用重组自交系分析水稻稻曲病抗性位点及效应

利用157个家系组成的大关稻/IR28重组自交系群体，采用高效引发稻曲病人工接种方法，以病情指数作为稻曲病的表型值，鉴定了亲本及157个重组自交系群体对水稻稻曲病的抗性。利用QTL Cartographer 软件，对水稻稻曲病抗性基因进行检测分析。检测到qFsr1、qFsr4、qFsr10、qFsr11和qFsr12共 5个QTL位点，分别位于第1、4、10、11和12染色体上，贡献率为9.8%~22.5%。根据抗性位点加性效应方向，在qFsr1、qFsr10、qFsr11和qFsr12位点上，亲本IR28存在抗稻曲病的增效等位基因，大关稻具有减效等位基因；而qFsr4位点抗性效应来源于大关稻。

QTL Analysis for Resistance to Rice False Smut by Using Recombinant Inbred Lines in Rice

A recombinant inbred line (RIL) population with 157 lines derived from an inter-subspecific cross of Daguandao/IR28 by the single seed descent method was used to detect quantitative trait loci (QTLs) conferring the resistance to rice false smut caused by Ustilaginoidea virens (Cooke) Takahashi. The disease index for the two parents and 157 RILs in response to rice false smut were scored and the QTLs responsible for rice false smut resistance were detected accordingly by QTL Cartographer software. Five QTLs controlling false smut resistance were detected on chromosomes 1,4,10,11 and 12,respectively,with the phenotypic variance explained from 9.8% to 22.5%. The directions of the additive effects at the four loci qFsr1,qFsr10,qFsr11 and qFsr12 coincided with those predicted according to phenotypes of the parents. At these four loci,the IR28 alleles had positive effects against rice false smut,while Daguandao alleles showed negative effects. The resistance was attributed to the alleles from Daguandao at the loci qFsr4.