Biotype and resistance status of whitefly Bemisia tabaci in Beijing and Hunan areas

Key Words：Beijing, Hunan, Bemisia tabaci, biotype, insecticide resistance

Abstract：      The whitefly Bemisia tabaci(Gennadius) is one of the most important and difficult to control insect pests of vegetables and ornamental crops. Insecticides are still the most common control method for these pests. The resistance of different B. tabaci biotypes from Beijing and Hunan to 6 insecticides was investigated. The results showed that B. tabaci from these regions were of the Q and B biotypes. Insects from both areas were still susceptible to abamectin but had moderate to high resistance to nitenpyram and other neonicotinoid insecticides, including thiamethoxam and imidacloprid. The degree of resistance was much higher in Hunan than in Beijing, with the highest recorded resistance being 71.58-fold. Traditional insecticides including chlorpyrifos and bifenthrin showed low toxicity activity for B. tabaci adults.