论文部分内容阅读
本文采用野外罩枝放养幼虫以及观察林间样树上幼虫一昼夜自然落粪数等方法对危害枣树的枣步曲幼虫的排粪量的特性进行了研究 ,并应用排粪量来推算枣树上的虫口密度。结果表明 :枣步曲幼虫的排粪量与日平均气温及昼夜温度的变化密切相关 ,但各龄幼虫间变化不大 ;枣步曲幼虫的排粪量随着龄期的增长而呈几何级数增加 ;枣步曲幼虫在枣树上的分布比较均匀 ,各方位间无显著差 ;建立了以日平均气温和排粪量为自变量来推算出虫口密度的动态模型n =mF =m1 6849+0 81 42T
In this paper, the characteristics of jujube jujube larvae detritus and juvenile jujube jujube larvae were studied by using shoot-covering larvae and observing the number of natural faecal excrement of larvae on the forest-like tree day and night. Insect density on the mouth. The results showed that the excreta amount of jujube larvae was closely related to the daily mean air temperature and the changes of diurnal temperature, but the larvae did not change much in all the larvae. The excretion of larvae of jujube larvae increased geometrically Jujube larvae distributed more evenly on jujube trees and there was no significant difference among all directions. A dynamic model was established to estimate the population density of insects by daily average temperature and defecation volume as n = mF = m1 6849 +0 81 42T