Insecticide resistance in Bemisia tabaci : A global perspective

Abstract

Current management strategies for Bemisia tabaci are severely constrained by the propensity of these species to develop resistance to insecticides. The breadth and geographical extent and breadth of resistance continue to increase, and many novel compounds are now affected in addition to chemical classes used widely in the past. Factors likely to promote the build-up and spread of resistance include (i) a haplodiploid breeding system enabling the rapid selection and fixation of resistance genes (ii) its breeding cycle on a succession of treated host plants; and (iii) its occurrence on high value crops that are widely traded internationally. There has been substantial progress with resolving the mechanistic basis of many forms of resistance, but others remain poorly characterised, other than at a phenotypic level. This paper will provide an update on the known incidence of resistance in B. tabaci, its practical consequences, and available information on the mechanisms responsible and their cross-resistance implications. As mechanisms become better understood, there is exciting scope for investigating the homology of resistance traits and genes between potentially reproductively-isolated biotypes, and the possible role of resistance in influencing changes in biotype composition. In this context, steps to expand the range of genomics-related tools applicable to B. tabaci are very welcome. These will provide valuable additional resources for the resistance research community