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草地螟是我区历史上发生危害严重的一个害虫,曾于1954、1956年大发生,仅这两年为害农作物291.1万亩,危害草场133.3万亩,被害减产达10—20%,严重的被害40—50%,59年为中等偏重发生,以后草地螟发生程度逐渐下降,甚至基本不发生为害。1963年于乌盟兴和县调查,越冬代成虫期仅4天,一代幼虫每亩有虫2—8头。1976年—1978年在乌盟凉城县、丰镇、察右前旗、兴和县出现越冬代成虫且虫量逐年上升,但幼虫零星发生。1979年我区西部草地螟突然大发生,成为我区主要暴发性社会害虫。现将几年来草地螟发生情况总结如下:
Meadow borer is a serious pest in the history of our district. It occurred in 1954 and 1956, affecting a total of 2,911,000 mu of crops and 1,333,000 mu of grassland in the past two years, with a yield reduction of 10-20% and serious victimization 40 - 50%, 59 years of moderately heavier occurrence, later the degree of occurrence of meadow moth gradually decreased, or even basic harm. In 1963 in Wuhe Xinghe County survey, overwintering on behalf of the adult period of only 4 days, a generation of larvae per acre 2-8 head. From 1976 to 1978, overwintering generations of adult worms appeared in Liangcheng County, Fengzhen, Chayouqian Banner, Xinghe County, Ulsun Province. The number of pests increased year by year, but larvae sporadically occurred. In 1979, the sudden occurrence of the western meadow moth in our district suddenly became the major outbreak social pest in our district. The past few years now the occurrence of meadow moths are summarized as follows: