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沾叶独枝来源于广东陆丰籼型地方稻种,它对华南稻区稻瘟病菌具有广谱抗性.为了挖掘和鉴定沾叶独枝含有的稻瘟病抗性基因,利用对五丰B (WB)致病、对沾叶独枝非致病的稻瘟病菌代表菌株GD08-T19接种以沾叶独枝为抗性供体、WB为感病亲本获得的F2群体.菌株GD08-T19在F2后代群体的抗感比率为15R:IS,其抗性由两个显性基因控制.利用已开发的Pi1,Pi2,Pi9,Pii,Pish,Pita等抗稻瘟病基因功能标记分别检测了沾叶独枝,研究表明沾叶独枝含有Pita基因.为了鉴定沾叶独枝另一抗性基因,选用300个平均分布于水稻12条染色体上的SSR标记对由GD08-T19接种的F2代群体构建的抗病池和感病池进行筛选和连锁分析.发现位于第6染色体上的2个SSR标记RM19769和RM19959与抗性基因连锁.进一步的定位区域扩充标记连锁分析表明,有6个标记RM19792、RM19804、GDAP41、RM19818、ESR6、RM19844与目的抗性基因连锁.目的基因被初步定位于Pi2/Pi9/Pi50区域.目标区域的Pi50等位基因测序表明沾叶独枝的另一目的抗稻瘟病基因为Pi50本身.“,”Zhanyeduzhi (ZYDZ) is an excellent resistant indica rice variety in Guangdong,which displayed broadspectrum resistance against rice blast fungus in South China.To excavate and identify the rice blast resistance genes which containing in ZYDZ,the representative isolate GD08-T19 compatible to Wufeng B (WB) but imcompatible to ZYDZ was used to inoculate the F2 population which derived from a cross between ZYDZ (as a resistant donor)and Wufeng B (as a susceptible parent).The resistant/susceptible ratio of F2 population was 15R:1S against GD08-T19,which indicated that the resistance of ZYDZ was controlled by two dominant resistance genes.The function markers of Pi1,Pi2,Pi9,Pii,Pish and Pita were used to detect if the donor had these resistance genes respectively,the results showed that was ZYDZ contained Pita gene.In order to identify another resistance gene,300 SSR markers which distributed on 12 rice chromosomes equally were used to screen the resistant and susceptible pool constructed by F2 population against isolate GD08-T19.The results showed that two SSR markers,RM19769 and RM19959 with chromosome 6 were linked to the resistance gene.Further linkage analysis showed that six markers RM19792,RM19804,GDAP41,RM19818,ESR6 and RM19844 were linked to the target resistance gene.The target gene was preliminarily located in the Pi2/Pi9/Pi50 region.The allele sequencing results of Pi50 in the target region indicated that another blast resistance gene was Pi50 in ZYDZ.