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玉米螟在吉林一年发生1~2代。不论一年发生几代,都是以最后一代的老熟幼虫在寄主的秸秆、穗轴、根茬及杂草里越冬,其中75%以上幼虫在玉米秸秆内越冬。越冬幼虫春季化蛹、羽化、飞到田间产卵。一、发生条件玉米螟发生的轻重和为害程度与越冬基数、气候、天敌及寄主植物的种类、品种和生育期等有着密切的关系。1.越冬基数一般幼虫越冬基数大的年份,田间卵量和被害率就高。如果百秆越冬活虫量在50头以下发生轻;在
Corn borer occurred in Jilin a year or two generations. Regardless of several generations a year, the larvae of the last generation are overwintering in the straw, cob, stubble and weed of the host, and over 75% of the larvae winter in the corn straw. Overwintering spring pupa pupation, emergence, fly to the field to lay eggs. First, the occurrence of conditions Occurrence of maize borer severity and damage degree and overwintering base, climate, natural enemies and the host plant species, species and growth period are closely related. 1 overwintering base general larvae overwinter base of a large number of years, the field of eggs and the victimization rate is high. If the stalks live over the amount of live insects occur in the following 50 light;