【摘要】 本研究将以前在稻瘟病菌菌株S1522获得的与决定对水稻品种梅雨明无毒性的基因（AVR-Pik^m）相连锁的1个RAPD标记OPO12₁₀₀₀进行了克隆和鉴定。核苷酸序列测定与分析结果表明:OPO12₁₀₀₀的大小为946个碱基,不含有与已报道的稻瘟病菌Mg-SINE、Fosburry、Magyy、Grasshopper、Pot2以及Pot3等同源的重复序列。根据OPO12₁₀₀₀的核苷酸序列,设计了1对24个核苷酸的特异引物,对无毒表型亲本S1522和毒性表型亲本S159、无毒表型群体基因池、毒性表型基因池以及有性杂交后代108个菌株进行了PCR扩增,所有无毒表型的菌株均能特异性地扩增出1条与OPO12₁₀₀₀大小相同的DNA条带,而毒性表型的菌株除5个重组个体外,均不能扩增出这条特异带。此结果表明,与稻瘟病菌无毒基因AVR-Pik^m连锁的RAPD标记OPO12₁₀₀₀被成功地转化为SCAR标记,为进一步通过染色体步移克隆该无毒基因奠定了基础。更多还原

【Abstract】 A randomly amplified polymorphic DNA （RAPD） marker, OPO12₁₀₀₀, which is closely linked to the avirulencegene AVR-Pik^m conferring avirulence in Magnaporthe grisea on rice cultivar Tsuyuake, was cloned and sequenced. Se-quence analysis showed that OPO12₁₀₀₀ was 946 bp in length and did not contain any sequence homologous with the previ-ously reported Mg-SINE, Fosburry, Magyy, Grasshopper, Pot2 and Pot3. According to the sequence, a pair of 24 merprimers was designed and used in PCR with templates for an avirulent parental strain S1522, a virulent parental strainS159 and 108 progenies from the cross S1522×S159. The PCR amplification produced a single DNA band of ahaut 1000 bpwhich was as the same as OPO12₁₀₀₀ in the avirulen strains while no amplification was detected in the virulent strains exceptfor 5 virulent recombinants. The results indicated that the RAPD marker, OPO12₁₀₀₀, was converted into a SCAR markersuccessfully and it could be used to initiate chromosome walking for cloning of the target gene.更多还原