我国小麦秆锈菌群体毒性基因的初步研究

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

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。

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.