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麦红吸浆虫五十年代在引黄灌区曾猖獗为害,后经大力防治,20多年来未发生明显为害。八十年代以来,由于多种原因,回升较快,又造成了历史性灾情重现,据1984、85两年普查,发生区已扩展到平罗、永宁、中卫及银川郊区共5县(区),其中平罗县以及贺兰的大部分乡是新发生区,发生总面积达30余万亩,全发生区中以贺兰县面积最大,为害最重。1985年在重发区调查,一般10复网扑到成虫35～210头,最多的1252头。扒麦垄目测检查,一眼可望见成虫10～20头。贺兰县常信乡于麦收后淘土检查,土壤中虫口密度平均每平方公尺4290条。剥穗检查,虫穗率达90％以上。虫粒率40
In the 1950s, the midges were used to be rampant in the Yellow River Diversion Irrigation District. After vigorous prevention and control, no significant damage occurred in more than 20 years. Since the 1980s, due to a variety of reasons, rapid recovery has caused a historic disaster to recur. According to the 1984 and 1985 censuses, the occurrence zone has expanded to five counties (Pingluo, Yongning, Zhongwei and Yinchuan suburbs) ), Of which most of Pingluo County and Helan Township is a new occurrence area, with a total area of more than 30 acres, Helan County, the largest occurrence of the area, the most serious damage. Survey in the reclamation area in 1985, generally 10 complex networks flutter adult 35 ~ 210, up to 1252. Grilled wheat ridge visual inspection, one can expect to see adult 10 to 20 heads. Helan County, often letter Township in the wheat harvest after the Amoy inspection, soil insect population density average 4290 per square meter. Peeling inspection, worm rate of 90% or more. Insect grain rate 40