褐稻虱在我省主要为害晚稻,轻者影响稻谷饱满程度,重者造成稻株枯死倒伏。一九六八年以来差不多连年严重发生,成为我省水稻生产的主要害虫。一、年发生世代。萧山地区褐稻虱在稻田中初次出现的时间,两年来都在七月初,一九七三年是七月一日,一九七四年是七月二日。从迁入代成虫始见后,一般能在稻田繁殖四个世代。二、越冬调查。一九七三年和一九七四年冬春调查,没有在双穗雀稗、狗牙根、千金子 Brown planthopper in late rice damage in the province, the light affect the full extent of rice, heavy rice caused by dead weight lodging. It happened almost continuously after 1968 and became the main pest of rice production in our province. First, there are generations. The first occurrence of brown planthopper in the paddy field in Xiaoshan was in early July in two years, July 1 in 1973 and July 2 in 1974. After migrating into the adult from the beginning, the general breeding in the paddy four generations. Second, the winter investigation. The winter and spring surveys of 1973 and 1974 did not show any significant differences in the values ​​of Paspalum, Bermudagrass,