The cotton aphid, Aphis gossypii (Glover) (Hemiptera:Aphididae), is a highly polyphagous pest that directly or indirectly damages cultivated plants. Six field-collected populations of cotton aphid, A. gossypii (BY-A, BY-B, YJ-A, YJ-B, CJ-A, and CJ-B) were tested for susceptibility to 14 different insecticides. Most population exhibited high to very high levels of resistance to neonicotinoid. Among them, a strain showing resistance to imidacloprid were selected and showed 1,543-fold in resistance as compared with susceptible strain. Piperonyl butoxide (PBO), diethyl maleate (DEM), and S,S,S tributyl-phosphorothiolate (DEF) failed to synergize imidacloprid in this resistant population. In addition, the activity of detoxification enzymes (P450, EST, GST) were no differences between susceptibility and imidalcoprid resistance strain. However, by analyzing the nicotinic acetylcholine receptor β1 subunit loop D, R81T point mutation was detected in BY-A, BY-B, YJ-A, and YJ-B strain.

• Ju-Il Kim(Highland Agriculture Research Center, NICS, RDA)
• Hyun-Na Koo(Department of Plant Medicine, Chungbuk National University)
• Gil-Hah Kim(Department of Plant Medicine, Chungbuk National University)
• Young-Uk Park(Department of Plant Medicine, Chungbuk National University)
• Sang-Eun Park(Department of Plant Medicine, Chungbuk National University)
• Jeong-Jin An(Department of Plant Medicine, Chungbuk National University)