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农村实行家庭承包责任制后,非承包的沟渠、坡堤、田埂常年失管,杂草丛生,为稻蝗提供了繁殖滋生的场所,加上农民放松了虫害防治,以致中华稻蝗近几年来已逐年上升为我市水稻的主要害虫之一。1983年全市发生面积仅20万亩,每平方米0.1～0.2头;至1985年已发展至40万亩,每平方米0.4～0.5头;1986年达到70万亩,每平方米0.5～0.6头;1987年猛增到110万亩,每平方米0.5～0.9头,局部高达10头以上;1988年继续猛增,发生面积达160余万亩,每平方米0.9～1.4头,局部高达45头以上。据不完全统
In rural areas, after the household contract responsibility system was implemented in rural areas, non-contract ditches, bank slopes and fields were perennially dropped and weeds were overgrown, breeding areas for rice locusts were provided. Coupling with the peasants’ relaxation of pest control, It has been one of the major pests of rice in our city year by year. In 1983, the city only had an area of 200,000 mu and 0.1-0.2 m 2 per square meter. It has grown to 400,000 mu in 1985 to 0.4-0.5 m 2 per square meter. In 1986, it reached 70 million mu of 0.5-0.6 m 2 ; 1987 soared to 1.1 million mu, 0.5 ~ 0.9 head per square meter, some as high as 10; in 1988 continued to surge, occurred in an area of 160 mu, 0.9 ~ 1.4 per square meter, as many as 45 the above. According to incomplete system