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郾城县地处黄淮平原,玉米种植面积、单产、总产均占秋粮的首位。1977年以来,玉米种植面积一直在30万亩以上,1981年达36.6万亩,占秋粮面积的50.5%;总产量也占秋粮总产的56.2%。玉米螟Ostrinia furnacalis Guenee是危害玉米的主要害虫,一年发生三代,以一代危害最重,三代次之,二代较轻。玉米螟的天敌种类较多,据记载有70多种,是抑制玉米螟种群数量的主要自然因素之一。为了弄清河南郾城县的玉米螟天敌资源,为保护利用提供依据,笔者等于1982年对玉米螟的天敌种类及主要寄生蜂——螟虫长
Tancheng County is located in the Huanghuai Plain, corn acreage, yield, total output of autumn accounted for the first place. Since 1977, corn acreage has been above 300000 acres, 366000 acres in 1981, accounting for 50.5% of autumn grain area; total output also accounted for 56.2% of the total output of autumn crops. Corn borer Ostrinia furnacalis Guenee is the major pest that endangers corn. Three generations occur a year, one generation harms the most, the third generation second and the second generation lighter. Corn borer more natural enemies, according to records of more than 70 species, is one of the main natural factors inhibiting the population of corn borer. In order to understand natural enemies of corn borer in Tancheng County, Henan Province, in order to provide the basis for protection and utilization, the author is equal to the natural enemies of corn borer in 1982 and the main parasitoids - stem borer