夏玉米成熟后期茎腐病对千粒重的影响

Effect of Stem Rot Disease at Late Maturity on Thousand-Grain Weight of Summer Corn

2014年9月14～18日连续阴雨天导致玉米茎腐病大发生。调查结果表明，国家黄淮海夏玉米区域试验的13个参试品种，从发病到收获6d内，其茎腐果穗千粒重比正常果穗减少3．28％～9．56％，其中晚熟、灌浆时间长的品种1-11的茎腐病果穗的千粒重减少最多，达9．56％，灌浆开始晚的1-2、1-7、1-12的茎腐果穗千粒重减少在7％以上，也高于其他品种；国家玉米产业技术体系黄淮海区域筛选试验的7个参试品种，从发病到收获4d内，其茎腐果穗千粒重比正常果穗减少1．93％～8．56％，其中吐丝最晚的诺达1号茎腐病果穗千粒重减少最多，达8．56％，吐丝期较晚的先玉688和先玉335，其茎腐果穗千粒重比正常果穗减少7．84％和6．28％，高于其他品种。晚熟品种、吐丝期晚的品种受到的不利影响大。

Continuous rainy days from September 14 to 18 in 2014 led to the outbreak of corn stem rot disease. The results of investigation showed that for the 13 varieties in the state - level regional tests, the 1 000 - grain weight of infected plants decreased by 3.28% - 9.56% during 6 days from incidence to har- vest. In which, the late -maturing variety 1 - 11 with longer filling time decreased the most as 9.56% ; and then the varieties 1 -2, 1 -7 and 1 -12 with the filling time beginning later, which decreased by over 7%. For the 7 varieties in the Huang - Huai - Hal regional tests, the 1 000 - grain weight of infected plants de- creased by 1.93% -8.56% during 4 days from incidence to harvest. In which, the variety Nuoda 1 with the latest silking time decreased the largest as 8.56% ; and then the varieties Xianyu 688 and Xianyu 335, which decreased by 7.84% and 6.28%. In conclusion, the late -maturing or late -silking varieties suffered larger negative influences.