基于无毒基因的晚疫病菌指纹类型与致病型关系研究

Correlation between pathotype and DNA fingerprinting pattern based on avirulence genes of Phytophthora infestans

由致病疫霉Phytophthora infestans （Mont） de Bary引起的晚疫病是马铃薯生产上可导致绝收的世界性病害,在我国各地均有发生和流行[1]。传统的致病型鉴别只局限于表型上的分析,无法对复杂多变的晚疫病菌致病型变化进行快速准确的预测,因此有必要探索新的方法来弥补常规手段的不足,以便更加准确有效地监测其变化趋势。晚疫病菌与寄主马铃薯这一病理体系中的单一抗性基因和相应的无毒基因符合典型＂基因对基因＂学说,

Four specific primers were designed according to the sequences of avirulence genes of Phytophthora infestans in GenBank and 88 P.infestans isolates from various regions were used for amplification by PCR technique with the primers.Seven types of DNA fingerprinting were obtained by assortment of the bands of PCR products.Meanwhile,pathotypes were identified with 11 different potato cultivars carrying known dominant mono-genes R1-R11 according to the response of resistance and susceptibility,the results showed that 88 isolates were separated into 4 groups at 44% genetic similarity level.There was no obvious correlation between pathotype of the pathogen and DNA fingerprinting pattern based on avirulence genes in this study.