稻瘟菌对水稻品种梅雨明的无毒性的遗传分析和分子标记

 将交配型为a、并对水稻品种梅雨明不致病的稻瘟菌菌株S1522与对该品种致病的、交配型为A的稻瘟菌菌株P131和S159杂交,分别获得了24和56个单子囊孢子后代。致病性测定结果表明:这些后代菌株在梅雨明上的致病个体与不致病个体的比例近等于1:1。由此推测:稻瘟菌对水稻品种梅雨明的无毒性是由1个基因控制的。进一步通过RAPD比较了致病后代与不致病后代的DNA多态型,获得了1个与该无毒基因连锁的、长度为1000 bp的RAPD标记,两者间的遗传距离为3.7cM。

IDENTIFICATION OF A RAPD MARKER LINKED WITH THE LOCUS IN RICE BLAST FUNGUS CONFERING AVIRULENCE TO RICE CULTIVAR TSUYUAKE

Twenty-four and fifty-six mono-ascospore progenies were obtained from two crosses of the strains of rice blast fungus, S1522 with P131 and S159. The strain S1522 belonging to mating type a is avirulent, and P131 and S159 belonging to mating type A are virulent to rice cultivar Tsuyuake. Pathogenicity test showed that ratio of avirulent progenies to virulent oneswas approximately 1 : 1, indicating that a single locus confers the avirulence in S1522 to Tsuyuake. RAPD technique was used to compare difference in DNA polymorphism between the avirulent and virulent progenies. One RAPD marker with about 1 000 bp was found closely linked with the avirulence locus, and genetic distance between the marker and the avirulence locus is about 3.7 cM.