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草地螟是我国北方农作物和牧草的重要害虫。其发生常表现来势猛、密度大、危害严重,如防治不及时,即可造成毁灭性的灾害。草地螟在国外早已有发生和研究资料发表,国内在五十年代中期曾有猖獗为害的记载。但是,该虫自1957年曾严重发生以来,几乎有20年的时间一直没有大量出现,至1977年起,种群数量又急剧上升,1979、1980连续两年严重发生,1982年出现大发生,一、二、三代幼虫都造成严重危害,发生面积在一亿亩以上,再次上升为我国北方最严重的农业害虫。据黑龙江、吉林、内蒙古三省(区)测算,1982年因防治草地
Meadow borer is an important pest of crops and forage in northern China. Its occurrence often fierce momentum, density, serious harm, such as control is not timely, you can cause devastating disasters. Meadow borers have occurred in foreign countries and research data published in the mid-1950s have rampant record. However, since the pest had been severely affected in 1957, there has been no substantial emergence for a substantial period of 20 years. Since 1977, the population has risen sharply again, with serious occurrences in 1979 and 1980 for two consecutive years. In 1982, a massive occurrence occurred. One , Second and third generation larvae have caused serious harm, the occurrence of an area of more than 100 million mu, once again rose to the most serious agricultural pests in northern China. According to Heilongjiang, Jilin, Inner Mongolia, three provinces (regions) estimated that in 1982 due to grassland control