甜菜夜蛾在河南省一年发生4～5代,尤以7～8月间即第三、四代幼虫发生量最大,对农作物危害最甚。成虫白天隐匿在杂草、枯叶及土缝等处,夜间活动,20～23时活动最盛,进行取食、交尾和产卵,趋光性强,卵多产于叶背或叶柄部,平铺一层或多层重叠,卵块上披有白色鳞毛。每头雌蛾产卵100～600粒,最多产卵1700粒,卵期3～6天。3龄 Beet armyworm occurred in Henan Province for 4 to 5 generations a year, especially in July to August that the third and fourth generation larvae occur the most, the worst damage to crops. Adult during the day hidden in the weeds, dead leaves and soil seams and other places, night activities, activities from 20 to 23 when the peak, for feeding, mating and spawning, phototropism, egg prolific in the leaf back or petiole, tiled Layers or layers overlap with white scales on ovum. Each female moth spawns 100 ~ 600, a maximum of 1700 eggs, eggs, 3 to 6 days. 3rd age