【摘要】 稻瘟病是水稻(Oryza sativa L.)三大病害之一,对水稻产量和品质造成了严重的影响。本研究利用优良恢复系R287与广谱抗稻瘟品种细麻线的BC3F1回交群体构建的分子标记遗传连锁图谱,并通过全生育期自然诱发稻瘟病进行抗性鉴定。结果显示,全基因组分析共定位到16个抗叶瘟和13个抗穗颈瘟相关的QTLs,所有抗性QTL均来源于细麻线。其中q BR3是位于第3染色体上同时控制水稻叶瘟和穗颈瘟抗性效应的QTL,其能够提高叶瘟抗性2个数量级和降低穗颈瘟发病率40%左右。q BR3对叶瘟和穗颈瘟的抗性LOD值分别为18.63和22.77,解释的表型变异率分别为21.20%和26.10%。通过对水稻已有稻瘟病抗性位点的定位结果分析,发现q BR3可能是一个新的广谱抗性QTL位点。本研究结果为稻瘟病抗性育种提供了新的基因资源。更多还原

【Abstract】 Rice blast is one of the three major diseases of rice(Oryza sativa L.),which cause serious influence on rice yield and quality.A molecular marker linkage map was builded using a BC3F1 backcross populations from an elite restorer lines R287 and a broad-spectrum blast resistance rice cultivar Ximaxian in this research.Through genome-wide QTL(quantitative trait loci) analysis with the phenotype of rice blast under natural infection condition,16 QTLs were resistance to leaf blast at tillering stage(RT),13 QTLs were resistance to panicle neck blast(RN) at maturation stage,and all of the resistance QTLs were from A111.QTL q BR3 located on chromosome3,was resistance to leaf blast and panicle blast with the LOD value of 18.63 at tillering stage and 22.77 at maturation stage,explained the phenotypic variations of 21.2% and 26.1%,which can improve 2 degree of leaf blast and reduce the incidence of panicle neck blast with 40%.Through the comparison of indentified QTLs of rice blast loci,q BR-3 may be a new broad-spectrum resistance QTL,which can be used in rice blast breeding as a new gene resource.更多还原