果内核桃举肢蛾低龄幼虫防治研究初报

核桃是山区主要经济树种之一,由于核桃举肢蛾(Atrijuglous hetaonei yang)的为害,使核桃大幅度减产、变质,甚致绝收。过去的防治目标集中在果外的各个虫态的防治,防止幼虫蛀入果内,一旦蛀入,多采取摘掉或拾毁虫果,减少了当年的收入,或者是刨树盘树上、树下多次喷药防治成虫,有条件的地区可以收到较好的效果。但是核桃多分布在山区,刨树盘难;干高冠大的树不易喷药,加上山区缺水,连续喷药不易做到。为探讨解决这一问题,1988-1991年,我们作了用高压注射机将久效磷注射到树干内,防治果内低龄幼虫的研究。

PRELIMINARY REPORT ON THE CONTROL OF YOUNG LARVAE OF ATRIJUGLOUS HETAOHEI YANG

The aim of this study was to control the young larvae of Atrijuglous hetaohei in the walnut fruits. A high pressure injector was used to inject systemical insecticides into the tree trunk and the insecticides were transported to the fruits by the tree fluids. Based on the dynamics of insecticides in thefruits, its effective period and the peak of adult emergence, the best timefor application and the proper dose of insecticides were decided. Once a yearto use this method, a mortality over 80% could be reached. This methodnot only can save time and labour but also is safe to natural enemies andenvironment, meanwhile it can not be affected by climate. No phytotoxicitieswere found and the residues were below the acceptable level.