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新疆南部主要棉区高密度棉田二代棉铃虫消亡因子主要可以归纳为天敌捕食、寄生、生理死亡、自然损失及人为活动等5个因子。1龄、5～6龄幼虫以及卵是新疆南部主要棉区二代棉铃虫田间自然消亡的主要阶段。各龄期幼虫田间自然存活率分别为53.3%、14.93%、10.60%、8.16%、6.69%、4.62%和2.58%。新疆南部棉产区二代棉铃虫总消亡率为97.95%,种群趋势指数(Ι)为8.8778。单头二代棉铃虫幼虫蛀食蕾数为0.921～14.35,平均4.92个,其数量与棉花蕾、花、铃数量减少率和产量损失呈正相关,综合棉铃虫危害和当前高密度棉花种植的生产成本,其防治指标为102粒卵/百株。
The second generation cotton bollworm demineralization factors in high-density cotton fields in southern Xinjiang mainly can be summarized as five factors of predation, parasitism, physiological death, natural loss and human activities. The first and fifth to sixth instar larvae as well as the eggs were the main stages of natural extinction of the second generation cotton bollworm in the main cotton area in southern Xinjiang. The natural survival rates of each larvae were 53.3%, 14.93%, 10.60%, 8.16%, 6.69%, 4.62% and 2.58%, respectively. The second generation cotton bollworm in southern cotton production area in southern Xinjiang had a total mortality of 97.95% and the population trend index (Ι) was 8.8778. The average numbers of earing buds of the single-headed second-generation cotton bollworm larvae were 0.921-14.35, with an average of 4.92. The numbers were related to the decreasing rate of cotton buds, flowers and bolls, and the yield loss. Combining the damage of cotton bollworm and the production of high-density cotton Cost, the control index of 102 eggs / one.