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通过44个品种83块麦田小麦纹枯病为害损失的测定,明确小麦纹枯病可引起小麦显著减产。病级1～4级,穗粒数降低依次为3.39％、4.68％、5.97％、15.99％,但差异并不显著。千粒重降低依次为2.15％、5.74％、10.53％、18.66％,减产依次为7.21％、12.22％、25.05％、37.72％,千粒重降低是减产的主导因素。同一病级的为害损失,品种间有明显的差异,表现出耐病和敏感的不同,稻茬小麦损失大于玉米茬小麦。小麦群体病株率(X_1)和病情指数(X_2)与产量损失率(L)的关系符合二次曲线:L=0.2072X_1-8.0747×10~(-5)X_1~2-1.4937(n=67,R=0.7181),L=0.4346X_2-3.4835×10~(-4)X_2~2-0.8787(n=67,R=0.7530)。防治适期在小麦返青拔节期3月15日前后。小麦纹枯病防治指标商榷为病株率15％,或病情指数4％。
Through the determination of the damage of wheat sheath blight on 83 varieties of wheat in 44 cultivars, it was clear that wheat sheath blight could cause significant decrease of wheat yield. Disease grade 1 to 4, reduce the number of spikelets were 3.39%, 4.68%, 5.97%, 15.99%, but the difference was not significant. The decrease of 1000-grain weight was 2.15%, 5.74%, 10.53% and 18.66%, respectively. The yield reduction was 7.21%, 12.22%, 25.05% and 37.72% respectively. The loss of the same level of damage, there are significant differences between varieties, showing resistance to disease and sensitive to different, wheat loss of rice stubble than corn stubble. The relationship between diseased plants rate (X_1) and disease index (X_2) and yield loss (L) of wheat population was in accordance with the quadratic curve: L = 0.2072X_1-8.0747 × 10 -5 -1_1.4937 (n = 67 , R = 0.7181), L = 0.4346X_2-3.4835 × 10 ~ (-4) X_2 ~ 2-0.8787 (n = 67, R = 0.7530). Preventative period in the wheat regurgitation jointing period around March 15. Wheat sheath blight disease control indicators for the diseased plant rate of 15%, or disease index of 4%.