小麦叶锈菌生理小种监测及其观点和方法的改进

Monitoring of Physiologic Races of Puccinia recondita f.sp. tritici and Improving of Viewpoint and Method of Research

1985～1990年小麦叶锈菌生理小种监测结果表明,在小种类型上,仍以频率在2%以上的小种叶中1、2、3、38和对洛夫林10等抗源能致病的洛10小种群为优势小种(群),洛10小种群急剧上升,由1985～1986年的18.33%上升至1989～1990年的57.65%.抗叶锈病的几个重要抗源洛夫林10、洛夫林13和山前麦等对这一小种群都不能抵抗,应引起育种和生产部门的高度重视.本文还对传统研究的观点和方法作了改进,放弃按分类学区分锈菌致病性的观点,代之以生物间遗传学研究小麦品种与叶锈菌相互作用的观点,调整了原有的鉴别寄主,采用毒力频率法和毒力组合法研究小麦品种与叶锈菌群体的关系,把过去研究个体品种与个体菌株的关系改变为研究品种群体与锈菌群体的关系.

The result of five years’ survey on the physiologic races of P. recondita f. sp. tritici indicated that races 1 , 2 , 3 , 38 and Lovrin 10 race group which was virulent to important sources of resistance were prevalent ones. Race 2 remained stable, race 1 slightly increased, race 3 and 38 slightly decreased, and Lovrin 10 race group incrcaced rapidly from 18.33% in 1985-1986 to 57.65% in 1989-1990 in frequency.Besides using the traditional method to monitor the races, effert was made to improve the viewpoint and method of research. The taxonomic point of view of distinguishing the races was abandoned and a view of interorgani-smal genetics was adopted to study host-parasite interaction. Seven of 8 differential hosts established by Chinese workers were replanced by 8 sources of resistance and cultivars which were important in relation to wheat production as well as breeding program. Metheds of virulence frequency and virulence association were used to analyze the interaction of wheat cultivars and the population of pathogen. Virulence frequency method revealed that some important sources of resistance such as Lovrin 10, Lovrin 13 and Predgornaja 2 were not ideal resistance parents for breeding. The virulence association method seemed to be useful in designing variety deployment rationally.