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祁东、安仁、桂阳三县位于我省南部,常年气温17～18℃,年雨量1400～1500毫米,无霜期280～290天,历年耕作栽培制度及水稻害虫发生危害情况大体可划分三个时期:1956年前以中稻为主,占70～80％,辅之双季间作稻、连作稻和一季晚稻混栽,水稻主要害虫以二化螟、稻飞虱为主,三化螟、稻叶蝉和稻纵卷叶虫为害较轻;1957～1969年,扩大了双季
The three counties of Qidong, Anren and Guiyang are located in the southern part of our province with annual temperature of 17-18 ℃, annual rainfall of 1400-1500 millimeters and frost-free period of 280-290 days. The tillage and cultivation system and pest damage of rice in the past years can be roughly divided into three periods : Dominated by middle rice in 1956, accounting for 70 ~ 80%, supplemented by double-season intercropping rice, continuous cropping rice and a season of late rice mixed planting, the main rice pests to Chilo suppressalis, planthopper-based, rice borer Cicada and rice leafroller damage less; 1957 ~ 1969, expanding the double season