The biotype and insecticide-resistance status of whiteflies, Bemisia tabaci (Hemiptera: Aleyrodidae), invading cropping systems in Xinjiang Uygur Autonomous Region, northwestern China

Xinjiang Uygur Autonomous Region in northwestern China is undergoing rapid development of its agricultural industries. Areas planted with cotton, grapes and vegetables have expanded dramatically in recent years. The tobacco whitefly, Bemisia tabaci, was first found in Xinjiang in 1998 on poinsettias (Enphorbia pulcherrima) and may have been imported to the region on that crop. Analysis of non-specific esterases using native polyacrylamide gel electrophoresis showed six samples of B. tabaci collected within a 200 km radius of Urumqi (Xinjiang's capital city) to belong to the highly invasive B biotype. The samples showed very similar profiles of insecticide resistance with very strong (> 1000-fold) resistance to pyrethroids, low to moderate resistance to imidacloprid and pyriproxyfen, and no resistance to abamectin. The implications for resistance management and contending with further invasions of aggressive B. tabaci biotypes are discussed. (c) 2006 Elsevier Ltd. All rights reserved.