柳蛎蚧的发生规律

Regulations of the Outbreak of Lepidosaphes salicina

柳蛎蚧在树干上的分布（累计虫口密度）规律为树干中部＞上部＞下部．树干上北方位虫口数较南方位虫口多．严冬、酷夏后死亡率高。通过对黑龙江省１０个市县柳蛎蚧发生面积与温度、湿度等气象因子关系的研究．建立了柳蛎蚧发生面积的多元线性回归预测模型、经检验证明．用该模型进行初步预测是可靠的。柳蛎蚧有螨类、瓢虫、寄生蜂及寄生蝇等多种天敌。

The distribution of Lepidosaphes salicina on the trunk (accumulated insect density) was in the order of middle>upper>lower. and the number of oyster scale on the north direction of the trunk were more numerous than on the south direction. their death rate was high in hot summer and severe winter. Investigation of the relationship between the occurring area of oyster scale and meteological factors such ifs humidity. temperature in ten cities and counties in Heilongjiang province formulated a multiple linear repression model for the prediction of the occurring area of oyster scale. Tests demonstrated that the use of this model for preliminary prediction gave reliable results. Acarids. ladybeetles. parasitic bees and parasitic flies were natural enemies of oyster scale.