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白杨透翅蛾是危害杨树的一种主要蛀干害虫,也是植物检疫对象之一。广泛分布于天津市郊、县及廊坊地区,特别是对一、二年生的毛白杨幼苗为害严重。初孵幼虫多在嫩芽幼梢处为害,从而造成隧端下垂枯萎;初龄幼虫侵入初期,在木质部与韧皮部之间为害,影响养分输导,致使被害处组织增生,形成瘤状虫瘿;幼虫长大后,沿隧道逐渐由木质部向髓部蛀入,严重时只留下少量皮层与木质部相连,遇风倒折,造成断顶或缺苗。该虫在天津市及廊坊地区一年发生一代,以幼虫在枝干中越冬。越冬幼虫四月份开始活动取食,五月初化蛹,五月下旬出现成虫,个别的初孵幼虫,六月初即开始侵入
Poplar moths are one of the major stem borers that endanger poplar and one of the plant quarantine objects. Widely distributed in the suburbs of Tianjin, Langfang and the county area, especially on the first and second year of the Poplar seedlings seriously harmed. The newly hatched larvae mostly in the shoots young shoot damage, resulting in the tunnel end drooping withered; the first instar larvae invaded the initial stage, between the xylem and phloem damage, affecting nutrient delivery, resulting in damage at the tissue proliferation, the formation of nodules; Larvae grow up along the tunnel gradually from the xylem to the medulla oblongata, in serious cases, leaving only a small amount of cortex connected with the xylem, the case of wind folding, resulting in broken or lack of seedlings. The insect in Tianjin and Langfang area a generation a year, with larvae in the branches of the winter. Overwintering larvae begin their activity feeding in April and pupae in early May. Adult and individual newly hatched larvae appear in late May and begin to invade in early June