黑翅小斑螟生物学特性及其防治

Studies on Bionomics and Control of Oligochroa atriquamella Hampson

黑翅小斑螟是危害黑荆树最严重的食叶害虫之一。该虫在福建省华安一年发生6代,林间世代重叠,以幼虫在黑荆树或地被物上吐丝结薄茧越冬,翌年3月下旬越冬幼虫陆续化蛹。幼虫5龄,吐丝缀叶结巢危害,幼虫历期16～24d,越冬幼虫历期117～148d。蛹期8～15d。成虫具趋光性,卵产于黑荆树嫩枝叶或旧虫巢上,每雌平均产卵103粒。大发生时用甲胺磷、氧化乐果800～1000倍液,氰戊菊酯2000倍液,溴氰菊酯4000倍液喷洒3～5龄幼虫或结合抚育人工摘除虫巢集中烧毁,防治效果均可达90％以上。

Oligcchroa atriqumella Hampson is one of the moot serious pest of Acacia mearnsii in Fujian Province. This paper reports the results of the studies on the bionomics and control of this pest from 1988 to 1991. It has 6 generations a year in Huaan, Fujian Province. In the field, there is an overlapping, generation. The larvae over winter within thin cocoons in the twigs and leaves or in the thick growth of grass or the fallen leaves. The overwintering larvae pupate in late-March next year. There are five instars for the larvae and they do harm by curling leaves of the plant. The overwintering larvae last 117-148 days and the others last 16~24 days; The pupae last 8-15 days. The adults fly to light at night. The eggs are laid individually on the tender twigs and tender leaves or insects nest and the average number of eggs laid per female is 103.Control methods include hand-collection of the larvae. Spraying insecticides such as diluted 40% Omethoate 800~1 000 times, 50% Methamidophos 800~1 000 times, 20% Fenvalerate 2000 times and 2.5% Decis 4000 times, respectively, upon 3~5 th larvae in laboratory were found to be very effective with a mortality of 90%.