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一、草地螟在我省发生区域及历年发生情况草地螟在我省五十年代初曾有过发生。自一九八○年以来,又开始发生,并逐步扩展。一九八○年仅在北部地区发现危害,目前在我省的北部、西北部、中部以及东南部地区都有发生,并程度不同的造成危害。自一九八○年一代幼虫危害逐年加重,一九八○年仅在辽北的开原县发生二百余亩;一九八二年全省为轻发生年,发生三十余万亩;一九八三年全省为中等偏轻发生年,局部中等偏重到大发生,发生面积八十余万亩,仅铁岭市就发生四十余万
First, the occurrence of grass borers in the region and the occurrence of the past years Meadow borers in our province had occurred in the early fifties. Since 1980, it has started to happen again and gradually expanded. In 1980, only the hazards were found in the northern areas. At present, they occur in the northern, northwestern, central and south-eastern regions of our province, and to varying degrees, they cause harm. Since 1980, the harm of the first generation larvae has been increasing year by year. In 1980, it only occurred in Kaiyuan County in northern Liaoning over 200 mu. In 1982, the province was light-prone and there were over 300,000 mu. In 1983, the province was moderately young, with some medium to large occurrences, with an area of more than 800,000 mu. There were more than 400,000 in Tieling alone