抗稻瘟病水稻材料谷梅2号中主效抗稻瘟病基因的成簇分布

Clustering of Major Genes Conferring Blast Resistance in Rice Cultivar Gumei 2

应用由籼稻组合中 15 6 /谷梅 2号衍生的 30 4个重组自交系 ,构建了由 177个标记组成、覆盖 12条水稻染色体的连锁图谱 ,定位控制水稻稻瘟病抗性的主效基因。前期定位的控制对中国稻瘟菌菌系 92 183(小种ZC1 5)穗瘟抗性的基因Pi2 5 (t)的位置得到进一步确认 ,位于第 6染色体标记A7和RG4 5 6之间 ,与A7和RG4 5 6的遗传距离分别为 1.7和 1 5cM ;发现群体对菲律宾稻瘟菌菌系Ca89(4谱系 )的叶瘟抗性由单基因控制 ,将该暂命名为Pi2 6 (t)的基因定位于第 6染色体标记B10和R6 74之间 ,与B10和R6 74的遗传距离分别为 5 .7和 2 5 .8cM。两个基因座位上的抗病等位基因均来源于谷梅 2号 ,表明谷梅 2号中存在控制水稻稻瘟病抗性的基因簇。

By using 304 recombinant inbred lines derived fro m indica rice cross Zhong 156/Gumei 2, a linkage map consisting of 177 marker loci and covering 12 rice chromosomes was constructed and employed for mapping genes conferring blast resistance in rice. Genomic location of gene P i25(t) conferring neck blast resistance to Chinese isolate 92-1 83 (race ZC 15) was verified to be located between markers A7 and RG456 on chromosome 6, with genetic distances of 1.7 cM and 1.5 cM to A7 and RG456, respe ctively. Leaf blast resistance of Gumei 2 to Philippine isolate Ca89 (lineage 4 ) was found to be controlled by a single gene. The gene tentatively designated a s Pi26(t) was located between markers B10 and R6 74 on chromosome 6, with genetic distances of 5.7 cM and 25.8 cM to B10 and R674 , respectively. Resistant alleles at both gene loci were derived from Gumei 2, indicating an existence of resistance gene clusters in Gumei 2.