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杨干透翅蛾是杨树的一种新的蛀干害虫。在西宁地区蛀害指数达43—79％,2年1代。成虫分主、副两组,6月和8月为发生盛期,幼虫侵蛀期主要在7月中、下旬和9月下旬—10月中旬。幼虫计有8龄。当年侵蛀后可长至1—4(5)龄;第二年可长至6—7(8)龄,在林木边材中造成“L”形蛀道;于第三年相继在蛀道内作茧化蛹、羽化。因有二个发生年度不同的群体相互演替,故每年都有一批成虫和初孵幼虫出现。树龄10年左右,胸径17.77±4.42厘米的四旁杨树最易受害;树干胸高1米以内和树冠基部分枝点附近,着卵最多,蛀害也最严重。侵蛀盛期喷布50％磷胺乳剂50—100倍液,毒杀小幼虫;辅以40％乐果乳剂或80％敌敌畏乳剂原液注孔,熏杀中、老龄幼虫。
Dryopteryx mongolica is a new borer to poplar. Index of soil damage in Xining 43-79%, 2 years 1 generation. The adults were divided into two groups. In June and August, the larvae invaded were mainly mid-July, late-September and late-mid-October. Larvae have 8 years old. In the same year, they can grow up to 1-4 (5) age invaders; the second year can grow to 6-7 (8) age, resulting in “L” shaped tunnels in the forest sapwood; in the third year, Cocoon pupation, eclosion. A number of adult and newly hatched larvae emerge each year because of two successive annual successions of different populations. Tree age of about 10 years, the diameter of 17.77 ± 4.42 centimeters chest diameter most vulnerable to damage; trunks chest height of less than 1 meter and crown branches near the base, the most eggs, the most serious damage. Moths emasculation spray 50% 50 ~ 50 times the concentration of phosphoric acid emulsion, killing small larvae; supplemented with 40% dimethoate emulsion or 80% dichlorvos liquid emulsion injection, fumigation, the old larvae.