黔北稻飞虱种群的消长动态

DYNAMICS OF RICE PLANTHOPPER POPULATION IN NORTHERN GUIZHOU

经过１１年的调查研究，得出了白背飞虱、褐飞虱两个种群在黔北一季中稻上的消长动态。两飞虱的迁入有同步突增的现象，发生量与迁入量关系密切；白背飞虱的主迁入时间比褐飞虱早，主要集中在５月底至６月上中旬和７月上中旬，田间种群高峰出现２次或１次，分别为６月中下旬和（或）７月中下旬，且年度间没有差异；褐飞虱主迁入迟，集中在７月下旬至８月上旬，田间种群高峰出现在８月中旬至下旬。稻飞虱在中稻上的种群消长表现出７月份以前田间以白背飞虱数量占绝对优势，进入８月份后褐飞虱虫口密度上升。

The dynamic state,growth and decline,of white back planthopper and brown planthopper in northern Guizhou was resulted after 11 years studies.The migration of two species was synchronous,and the population of the insects closely related to its migrant number.The main migration of white back planthopper was early than brown planthopper,it happened from the end of May to middle June, and early middle July.The population of the insects in the field presented two or one peaks in middle and late June, and middle and late July respectively and without any difference in different years;The main migration of brown planthopper was late,it centrated in late July and early August.The peak of population in the field occurred from middle to the end of August.Before July white back planthopper takes absolate majority,but the population density of the brown planthopper was increasing in August and damaged the rice plant in late stage of growth.