一九九○年全国小麦秆锈菌小种动态

1990年在我国17个省、市、自治区的42个县采集到小麦秆锈病(Puccinia graminis f.sp.tritici)标样129份,从中分离鉴定了183个菌株。小种命名中同时采用了原半开放式鉴别寄主系统和美国明尼苏达大学禾谷类锈病室代码(Pgt-code)系统构成的复合命名法,共鉴定出21C3和34C2两个小种类群,21C3-CHK,21C3-CFH,21C3-CKK,34C2-MFK,34C2-MKK 和34C2-MKR 等6个小种,其出现频率依次为61.20%、12.6%、7.7%、1.1%、1.1%和0.5%。21C3-CKH 为当前流行小种,21C3小种群的出现频率为97.3%,34C2类群为2.7%。在利用89个菌株对41个 Sr 单基因系的毒力频率测定中,没有发现对 Sr 9e、11和38有毒力的菌株,对Sr25,26,31,35,GT 和 Wld-1的毒力频率均在9%以下。

RACE IDENTIFICATION OF PUCCINIA GRAMINIS F.SP.TRITICI IN CHINA IN 1990

Wheat stem rust occured lightly in most part of China during 1990.It was analysed and identified with 183 isolates of 129 samples collectedfrom 42 counties of 17 provinces and autonomous regions.Races weredesignated according to the nomenclature of Roelfs's code and Stak-man's System(pgt-code).They were races 21C3 CKH,21C3CFH,21C3 CKK,34C2 MFK,34C2 MKK and 34C2 MKR,and theirpercentages were 61.2%,12.6%,7.7%,1.1%,1.1% or 0.5%,respec-tively,21C3 CKH was the dominant race and the next to it was 21C3CFH.21C3 was 97.3% and 34C2 was 2.7%.Their virulenees was detemined on 41 wheat lines of single gene.No virulence was found in single gene lines Sr9e,11 or 38 and viru-lence frequencies of 9% and less were found in Sr25,26,35,GT orWld-1.