我国小麦秆锈菌群体毒性基因的初步研究

利用29个抗秆锈病小麦单基因系(或近等基因系)对来自我国云南、陕西、辽宁、四川等16个省(区)的74个菌株进行了测试,分析了我国小麦秆锈菌群体的毒性基因频率、毒性因子、毒性值和毒性基因组合的多样性。结果表明:(1)毒性基因V6、V7b、V8a、V9d、V9g、V10、V17、V36、Vw1d—1的出现频率较高(68.9％—98.6％),其对应的抗性基因为目前我国小麦秆锈菌的无效基因;其次为V5、V9b、V13、V21、V24、V25、V27和V37(39.2％—62.2％);毒性基因V9e、V11、V22、V26、V29、V30、V31、V32、V33、V38、VGt和VTmp的出现频率达0％—30％,其对应的抗性基因为目前我国小麦秆锈菌的有效基因。(2)我国小麦秆锈菌群体毒性与北美相比存在着很大的异质性,其毒性因子和毒性值分别为7.0和701.05,且毒性基因组合比较丰富,分布较为均匀。

VIRULENCE GENES OF FUCCINIA GRAMINIS F. SP. TRTFICI POPULATION IN CHINA

74 isolates of Puccinia graminis f. sp. tritici obtained from 16 Provinces or Autonomous Regions in China were tested by using 29 monogenic lines (or near-isogenic lines) as differentials and the virulence gene frequency, virulence factor, virulence value and diversity of virulence gene combinations were analyzed. Results demonstrated. (1)The frequencies of virulence genes V6,V7b,V8a,V9d,V9g,V10,V17,V36,Vwld-l were 68. 9%-98. 6%,indicating that the corresponding resistance genes were ineffective to wheat stem rust population in China at present; followed by V5,V9b,V13,V21,V24,V25,V27,and V37 with frequencies of 39. 2% -62. 2% and V9e,V11,V22,V26,V29,V30,V31,V32,V33,V38,VGt,and VTmp with frequencies of 0%- 30% ,indicating that the corresponding resistance genes were effective. (2) The virulence factor and virulence value of wheat stem rust population in China were 7. 0 and 701. 05 respectively, differing from North America,and the virulence gene combinations were more abundant and more evenly distributed.