河南省主推小麦品种白粉病发生程度及流行动态研究

Occurrence degree and epidemic dynamics of powdery mildew on winter wheat varieties in Henan Province.

经１９９５～１９９７年的试验表明，河南省近几年推广的小麦品种６７％以上为感白粉病品种。极感品种（豫麦１３号）白粉病发生早，发病全盛期长，约３０ｄ，表观侵染速率（ｒ）达０１１～０１６，最终病指和病指曲线下面积（ＡＵＤＰＣ）都最高；高感品种豫麦２５等的最终病指及ＡＵＤＰＣ值分别比极感品种低１９％～６６％、４０％～７３％，发病早，发病全盛期２５～３０ｄ，ｒ值０１～０１５；中抗品种豫麦２１号、２４号、中育４号占３３％，没有免疫品种。中抗品种的最终病指及ＡＵＤＰＣ值比极感品种分别低８３％～９１％、８９％～９４％，且发病较晚，发病全盛期只有１０ｄ，ｒ值００６～０１１。

The results showed that more than 67% of winter wheat varieties were susceptible to powdery mildew in Henan. The powdery mildew not only occured early but also had a lengthy logistic phase for 30 days on extremely susceptible variety (Henan wheat 13). Its apparent infection rate (r) was 0. 11-0 16, the final disease index and the area under disease progress curve (AUDPC) were the largest among all varieties. The final disease index and AUDPC of high susceptible varieties were decreased 19%-66% and 40%-73% as compared with those of Henan wheat 13, respectively. Their logistic phase was 25 to 30 days and the apparent infection rate was 0 10-0 15. About 33% varieties were moderate resistant. The final disease index were 89% to 94% lower as compared with that of Henan wheat 13. Their logistic phase were only 10 days and the apparent infection rate were 0 16-0 11.