The entomopathogenic approach to whitefly management and its compatibility with insecticides

Management of Bemisia tabaci MEAM1 is a reoccurring event for many vegetable crops due to severe annual B. tabaci-induced economic injury. Insecticides such as imidacloprid, cyantraniliprole, and some insect growth regulars are commonly applied during the management of this species. However, alternative approaches for B. tabaci management are needed due to environmental and regulatory concerns and the development of insecticide resistance. Microbial biocontrol options, such as entomopathogenic nematodes (EPNs), are promising alternatives. Combining chemical and microbial approaches may be compatible with a whitefly management program and consequently reduce the sole reliance on other insecticide-only programs. The first objective of this study was to evaluate the compatibility of entomopathogens with insecticides. The second objective was to evaluate the efficacy of these insecticide-EPN combinations against B. tabaci in several experimental conditions. Several evaluations were conducted to determine the synergistic relationship between EPNs and insecticides in a combined application. Under laboratory conditions, compatibility between insecticides and EPNS was significantly high despite exposure to higher insecticide doses. When tested in the greenhouse, the mortality of B. tabaci following combined insecticide and EPN applications was comparable to insecticides in above-ground applications. This research elucidates the potential benefits of using entomopathogens for the management of B. tabaci under laboratory, greenhouse, and field conditions.