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我省应用赤眼蜂防治玉米螟从1973年以来防治面积逐渐扩大,近2～3年全省放蜂面积80～90万亩。有些单位已坚持多年大面积放蜂控制螟害,防治效果一般较好,卵寄生率70～80%,防治效果60～70%。但是放蜂治螟有的地方效果好,有的效果差。随着生产的发展,螟虫危害日益严重,百株玉米有虫200～300头,多的达1000头,减产5～10%以上,群众迫切要求防治。为此,我
Trichogramma application in our province to prevent and control corn borer since 1973, gradually expanding control area, the past 2 to 3 years the province put the bee area of 80 to 90 acres. Some units have persisted for years to put a large amount of bee control pests, the control effect is generally good, the egg parasitic rate of 70 to 80%, the control effect of 60 to 70%. However, some places have good effects of beekeeping, and some have poor results. With the development of production, the stem borers are more and more seriously endangered. Hundreds of corn have 200-300 heads, more than 1000 heads, and more than 5-10% reduction in production. The masses urgently demand prevention and treatment. For this, me