Rapid identification of races and species-specific pathotypes using DNA-fingerprinting

利用多位点探针Maggy和MGR586对日本稻瘟病菌的种群结构进行了研究。对大约300个分离物的分析表明，在日本当前的稻瘟病种群中存在两个离散的谱系。它们被指定为JL1和JL2。有两个谱系与之前在1960年前的采集中发现的五个谱系中的两个相对应，这表明日本稻瘟病种群的结构在1960-1976年间发生了巨大变化。对越南稻瘟病种群进行了Maggy探针DNA指纹分析和致病型分析。这些分析表明，越南北部地区的稻瘟病种群在遗传上比南部地区更具多样性。在这两个群体中，没有发现谱系和小种之间的关系，这表明“谱系排斥假说”不适用于这些群体。对稻瘟病菌、水稻分离物、小麦分离物、Panicum分离物、狗尾草分离物、Eleusine分离物和马唐分离物的6个寄主特异性亚群进行了DNA指纹实验，建立了DNA诊断体系。我们提出了以下公式来区分这些亚群：(1)HindIII MGR583：识别每个群(2)Sali Maggy：识别水稻和狗尾草分离物(3)EcoRV MGR583：识别小麦分离物(4)HindIII Pot2：识别马唐分离物

DNA fingerprinting with miltilocus probes, MAGGY and MGR586, were conducted to investigate the population structure of the rice blast fungus, Magnaporthe grisea in Japan. Analyses of ca. 300 isolates revealed that two discrete lineages exist in the current rice blast population in Japan. They were designated as JL1 and JL2. There two lineages corresponded to two of the five lineages previously detected in collections made before 1960, suggesting that the structure of the rice blast population in Japan had drastically changed during 1960-1976. Rice blast population in Vietnam were also subjected to DNA fingerprinting with MAGGY probe and the pathotype analysis. These analyses revealed that the blast population in the northern region of Vietnam is genetically more diverse than that in the southern region. In both populations no relationships were detected between lineages and races, suggesting that the "lineage exclusion hypothesis" is not applicable to those populations.DNA fingerprinting experiments were carried out for establishing a system of DNA-diagnosis of six host-specific subgroups of M. grisea ; Oryza isolates, Triticum isolates, Panicum isolates, Setaria isolates, Eleusine isolates, and Digitaria isolates. We propose the following formulas for distinguishing those subgroups.(1)HindIII+MGR583 : to identify each group(2)SalI+MAGGY : to identify the Oryza and the Setaria isolates(3)EcoRV+MGR583 : to identify the Triticum isolates(4)HindIII+Pot2 : to identify the Digitaria isolates