Abstract:Different populations of Myzus persicae (Sulzer) were collected from ten main tobacco regions in Yunnan and Guizhou Provinces. The resistance to fenvalerate, imidacloprid, omethoate, and methomyl was tested by topical application of capillary tube. The results showed that the resistance ratios of CX-population (the M.persicae (Sulzer) collected from Chuxiong area) to fenvalerate, omethoate, methomyl and imidacloprid were 26.87-, 10.02-, 6.00- and 5.83-folds, respectively compared with sensitive population. The resistance ratios of DL-population (collected from Dali area), LJ-population (collected from Lijiang area), SL-population (collected from Shilin area) and QJ-population (collected from Qujing area) to fenvalerate were 24.98-, 14.94-, 11.11- and 10.33-folds respectively, but still relatively sensitive to omethoate, methomyl and imidacloprid. The measures of managing the resistance should be taken as soon as possible. The five populations of M.persicae from Guizhou Province were still relatively sensitive to the tested insecticides.