树干涂毒环防治下树转移沙棘木蠹蛾幼虫研究

观察研究沙棘木蠹蛾当年生幼虫的下树转移危害习性，利用该习性采取在树干上涂毒环、绑毒绳的方法控制该虫。观察发现，2005年9月1日到18日，幼虫绝大多数是在09：00-16：00间下树转移，极少数是在20：00-08：00下树；2005年9月18日以后未曾在早上和夜晚观察到下树幼虫，幼虫都是在10：00-16：00间下树。幼虫从排粪处爬出，顺着树干向下爬，到地面时继续沿着树干钻入土层，最后找到适宜的场所，停留在树根部的树皮裂缝处。用中西杀灭菊酯与金天敌长效缓释剂按1：9的比例混合配成毒剂涂干，环宽5cm，施药第5天对沙棘木蠹蛾幼虫的防治效果为100％，第30天防治效果在80％以上。

Control of Holcocerus hippophaecolus larvae moving down tree with insecticidal ring on trunk

The habit of moving down tree of Holcocerus hippophaecolus larvae hatched in the year was investigated from August to October,2005 in Jianping County,Liaoning Province.Based on the investigation,the control tests were conducted with insecticidal ring and rope on trunk in 2005.The result showed that from September 1st to 18th,most larvae moved down trees between 09:00 and 16:00 while a few larvae moved down between 20:00 and 08:00.After September 18th,all the larvae moved down between 10:00 and 16:00.The larvae crawled out of the excretory hole,moved down along the trunk to the ground,got into the soil and finally stayed in bark cracks in root.Painting a ring 5 cm wide around the trunk with the mixture of 2 mL fenvalerate EC and 18 mL Jintiandi long-effective slow release EC at the height between 30 cm and 40 cm could kill 100% of the larvae 5 days after the application.The mortality was above 80% on the 30th day.