不同生育期玉米上草地贪夜蛾的发生为害规律

2019年在广东湛江、江门调查了玉米上草地贪夜蛾Spodoptera frugiperda (Smith)发生为害动态，分析了不同生育期玉米上该虫发生为害差异规律。发现各个地区草地贪夜蛾的虫口数量与玉米受害程度存在较大差异，呈现不均衡性；该虫对玉米苗期为害最严重，其次为大喇叭口期；建立了2个地区玉米6个生育期受害率与虫口数量之间的线性回归模型。研究结果可为草地贪夜蛾监测预警及防控提供参考。

Occurrence and damage of the fall armyworm Spodoptera frugiperda (Smith) at different growth stages of corn

The occurrence and damage dynamics of the fall armyworm Spodoptera frugiperda (Smith) on corn were investigated in Zhanjiang and Jiangmen, Guangdong in 2019, and the occurrence and damage regularity of the armyworm in different growth stages were analyzed. It was found that the armyworm density and damage degree to corn at different regions was different, showing imbalance. The damage to corn seedling stage of the armyworm was the most serious, followed by the big-bell-mouth stage. The linear regression models between the damage rate of corn and the pest density at six corn growth stages in two regions were established. The results provided the reference for monitoring, warning and control of the armyworm.