柳杉长卷蛾的生物学及其防治

Bionomics and Control of Homona issikii

柳杉长卷蛾是柳杉的主要害虫之一。在浙江文成县一年二代,以初孵幼虫在被取食的枯枝针叶内越冬,翌年4月中下旬开始活动。5月下旬出现成虫。卵产于嫩枝上或针叶基部,每雌蛾产43～254粒。幼虫共5龄,初孵幼虫取食叶肉,3龄后吐丝缠缀嫩梢成虫苞,在其内取食针叶和枝皮,老熟幼虫在虫苞内化蛹。室内外防治试验表明;对幼虫喷洒溴氰菊酯、甲胺磷、敌百虫、敌敌畏、氧化乐果及白僵菌均有良好效果。此外还可用人工摘除虫苞和灯光诱杀成虫。

Homona issikii Yasudas is an important insect pest of the Cryptomeria fortunei and C. japonica in East China and Taiwan Province. It has two generations per year in Wencheng county, Zhejiang province. Winter is passed as newly larvae in the inner of leaves of dying down branches to be eaten. The larvae begin to be active early April next year. The adult moths begin to appear in late May. It hides during the day in shaded of trees, mating and oviposition take place by day and night now and then. The eggs are laid masses on the surface of shoot and the base of leaves. Each female moth lays 43-254 eggs. The newly hatched larvae usually feed leaf flesh and only the epidermis will remain. Larvae over 3 instars web several shoot to form temporary nest, and feed on the leaves and epidermis of shoot by their nests. The larval stage has five instars. The mature larva pupates in the temporary nest.There are a number of natural enemies attacking this insect. Among then the important are Macrocentrus sp. and Beauveria bassiana. The result of experiments showed that Decamefhrin, Tamaron, Trichlorphon, Dichlorphos, Omethoate, Beauveria bassiana were very effective for the control of the larvae.