摘要
本文通过3年的定位观测研究,确定出赤松毛虫上树盛期为4月2日至4月5日,日均气温11.2℃,地下5cm深温度为15℃.幼虫暴食期为103d.从蛹至5龄幼虫生存系数为0.0047.产卵量与蛹重的回归方程为(?)=-155.456+193.918x.不同食叶水平油松材积生长量之间有显著差异,受害允许水平为50％以下,其单株载虫量最多不得超过18头,超过此指标应进行防治。
According to the fixed-place observations of three years, the peak time for larva of Dendrolimus spectabilis Butler to climb up trees from ground appears during the period of April 2-5 when the daily mean temperature is 11.2 ℃ and the soil temperature at 5cm beneath siol surface is 15℃.The greedily eating period of the larva is 103 days.The survival coefficient from pupa to fifth instar is 0.0047.And the regression
equation of egg amount and the pupa weight is y= - 155.456 + 193.918x. Different levels of needles eaten by larva result in significant differences of volume increment of Chinese pine.And the tolerable damage level is below 50%, or the numbers of the larva on a single tree should less than 18.If higher than the tolerable level, the control measures should be taken.
关键词
赤松毛虫
种群变动
防治
指标
Dendrolimus spectabilis Butler
population activity
control index
