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1.介壳虫危害加重的原因1.1气象因素北方的气候是十年九旱,对各种介壳虫的产卵和卵的孵化都是不利因素。所以,很多年以来,介壳虫一直是果园的次要害虫,没有对树体和果实造成危害和损失。因此,果园的管理人员疏忽了针对介壳虫的防治。可是,2002-2004年,北方大部地区降雨增多,有?
1. The reasons for the increased risk of scale insects 1.1 Meteorological factors The northern climate is ten years of nine dry, a variety of scale insects spawning and egg hatching are unfavorable factors. As a result, scale insects have been the secondary pests of orchards for many years without causing harm or loss to the trees and fruits. Therefore, the orchard managers neglected the scale control. However, from 2002 to 2004, the rainfall in most parts of northern China increased.