The occurrence law of rice water weevil ( RWW) was investigated in Leping City ,Jiangxi Prov-ince.The results indicated that the RWW occurred 2 generations per year in the double rice regions of Poyang Lake plain in Jiangxi Province .The RWW began to come out from the overwintering places when the tempera-ture was over 13 ℃,and then migrated to the fields .April 15th was the peak time of their coming out of the ground ,April-end was the peak of the adults ’ migration to the fields .The peak occurrence of adults in the fields was in the period from April-end to early May .The final stage of adults in the fields was in early June .A-dults of RWW oviposited and larvas hatched in May ,the peak of larva incubation was in early and middle May . Pupae occurred from early June ,and the pupation was in the middle ten days of June .The first generation a-dults emergenced from June ,and the peak emergence was in the middle ten days of July .The final stage of the first generation adults was in early August ,a few adults stayed in the fields to form the source of the second gen-eration in late rice season .The average of field insects was 22.95 per 100 hills of rice in 2011,the loss percentageof rice was 18%to 20%;the number of insects in the seriously damaged plots was 49.25 per 100 hills,the loss percentage of rice was 30%-35%.The occurrence area of Lissorhoptrus oryzophilus Kuschel in Jiangxi Province from 2007 to 2010 was expanded ,but the annual growth rate had a little decline compared with that in the past .%为明确江西省稻水象甲发生规律，田间调查了稻水象甲的发生动态，结果表明：鄱阳湖平原双季稻区稻水象甲一年发生2代。3月下旬温度升至13℃以上越冬成虫开始出土，出土高峰在4月15日，入迁本田高峰在4月底，4月底田间成虫盛发，终见期在6月初。5月上旬成虫产卵，幼虫孵化高峰在5月上、中旬。6月初幼虫结茧化蛹，中旬达化蛹高峰。6月下旬一代成虫羽化，7月中旬达到高峰，成虫终见期在8月初，极少量一代成虫构成二代虫源。2011年越冬代成虫盛发期平均田间虫量达22．95头/百丛，损失率为18％～20％；受害严重田块平均百丛虫量达49．25头，损失率为30％～35％。2007-2010年稻水象甲在江西省发生面积扩大，但年间同比增长在减缓。成虫偏好狗牙根、白茅等禾本科杂草。
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