桑螟发生规律及防治策略

通过室内饲养和大田调查 ,证实湖州地区桑螟DiaphaniapyloalisWalker年发生以 5代为主 ,少数年份有 4代 ;桑螟成灾主要集中在第 4,5代。大田桑螟消长同气候、养蚕形式、天敌、防治水平有密切关系 ,不同年份之间发生时间、数量差异很大。桑螟防治方法 :以调整养蚕布局为主 ,辅以化学防治。在大批桑螟 3龄前用药是药剂防治的关键。药剂有 :40 %桑宝乳油 1 1 4mg kg,养蚕安全间隔期 6～ 8d。

Occurrence regularity and control strategy of Diaphania pyloalis

The occurrence regularity and control methods of Diaphania pyloalis Walker were studied with raising in laboratory and investigating in fields. The results showed that Diaphania pyloalis had 5 generations each year in Huzhou District, but 4 generations sometimets. The 4th and 5th generations caused great damage. The occurrence time and quantity in various years were different. Population dynamics of Diaphania pyloalis contacted with climate, raising silkworm method, natural enemies and control level. Reasonably arranging silkworm raising was main control method. Chemical control was secondary method. Using insecticides before 3rd instar was the key of chemical control. Effective insecticide was 40% EC Sangbao. The safe period of raising silkworm was 6～8 days.