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小麦是一代棉铃虫的主要寄主之一,1990年以来,麦田一代棉铃虫发生量突然猛增,对小麦生产构成了威胁。1992年是有史以来发生最重的一年,河北省中南部麦区,田间幼虫量是历年同期平均值的几倍至几百倍,麦穗被害率达60％以上,减产3—5％。为减轻其危害,我们进行了麦田一代棉铃虫发生规律及防治技术的研究。本文根据近两年的调查结果,谈一下麦田一代棉铃虫的发生及防治,供参考。 一、发生特点 在冀南地区,棉铃虫越冬代成虫始见于4月中旬,4月下旬(约在25—28日)为成虫出现高峰期。4月21—23日田间开始见卵,盛期在4月底5月
Wheat is one of the main hosts of the generation of cotton bollworm. Since 1990, a sudden surge in the generation of cotton bollworm in the wheat field has posed a threat to the production of wheat. 1992 was the heaviest year in history. The quantity of larvae in the fields in central and southern Hebei Province was several times to several hundred times the average over the same period of previous years. The rate of wheat ear damage was over 60% and the yield was reduced by 3-5%. In order to reduce its harm, we carried out the research on the law of generation and control of cotton bollworm in wheat field. This article based on the findings of the past two years, talk about the generation of cotton bollworm and prevention and control for reference. First, the occurrence of characteristics In southern Hebei, the overwintering generation of cotton bollworm adults first appeared in mid-April, late April (about 25-28 days) adult peak. April 21-23 began to see eggs in the field, peaked in late April and May