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室内饲养和田间调查表明,棉铃虫在甘肃敦煌棉区年发生3～4代,第4代为不完全代。明确了各世代的盛发期和主要寄主作物。阐明了棉铃虫在本棉区可以安全越冬。越冬蛹主要分布在0～5cm的土层内,且四周地埂是棉铃虫越冬的主要场所,冬灌可显著降低越冬蛹的存活率。结合多方面调查资料分析,初步认为本市棉铃虫虫源以本地虫源为主。同时,还在变温条件下,饲养观察了本地区棉铃虫各代、各虫态的发育历期。
Indoor feeding and field surveys showed that cotton bollworm occurred in Dunhuang cotton area of Gansu for 3 to 4 generations and the fourth generation was incomplete. Clarified the flourishing period and major host crops of each generation. Clarified that the cotton bollworm in the cotton area can be safe wintering. Overwintering pupae were mainly distributed in the soil layer of 0 ~ 5cm, and the surrounding 埂 was the main site for overwintering cotton bollworm. Winter irrigation could significantly reduce the survival rate of wintering pupae. Combined with many survey data analysis, it is preliminarily believed that the source of the cotton bollworm in this city is local insect source. At the same time, we also observed the developmental stages of the cotton bollworm in each region and each insect state under variable temperature conditions.