Abstract: Resistance to some insecticides used commonly in different populations of the white-backed planthopper,Sogatella furcifera collected from Zhejiang,Guangxi,Yunnan and Hainan Province in China was measured.The specific activities of some resistance-associated enzymes,i.e.esterase,carboxylesterase,glutathione S-transferase and acetylcholinesterase from these populations were also measured.The resistant levels to malathion,methamidophos,isoprocarb and buprofezin were markedly higher in Yunnan and Hainan populations than in other populations,but considerably more heterogeneity in response to insecticides was found in Zhejiang and Guangxi populations.The specific activities of the enzymes were obviously higher in Zhejiang and Guangxi populations than in Yunnan and Hainan populations,and the distribution range of the enzyme activity was the widest in Zhejiang population,and the narrowest in Guangxi population.Finally,The relationship between the long-distance migration and the territorial difference in insecticide resistant level and activityes of the enzymes in the populations of this planthopper was discussed.

Key words: Sogatella furcifera, Insecticide resistance, Enzyme activity, land use, Dongting Lake area, ecosystem service value, spatial pattern, space-time evolvement