稻瘟菌致病性变异突变体的筛选及共分离分析

通过筛选稻瘟菌(Magnaporthe grisea)P131小种的REMI(Restriction Enzyme MediatedIntegration)转化体库获得对水稻品种梅雨明致病性变异的突变体,命名为PX1.与野生型菌株P131相比,该突变体对水稻品种梅雨明致病性丧失,在洋葱表皮上侵染钉形成率显著降低,而孢子萌发率和附着胞形成率差异不显著.遗传分析表明,该突变体的突变表型和潮霉素抗性标记共分离,说明突变是由于外源质粒插入引起的,因此,可以此为标记克隆控制该表型的基因.

Screening of a Pathogenicity Variation Mutant of Magnaporthe grisea and Its Cosegregation Analysis

The pathogenicity variation mutant PX1 that had lost pathogenicity to cultivar Tsuyuake was obtained by screening a REMI transformant library of Magnaporthe grisea P131 strain. The mutant has no difference with wild type P131 in conidia germination,appressorium formation and other biological characteristics(including sporulation capacity and colony morphology)except significantly reducing appressorium penetration on onion epidermis. Genetic analysis revealed that the mutation phenotype was cosegregats with the insertion marker, and that the mutation is due to the marker insertion which can be used for cloning the gene.