Mycoinsecticide effects of Beauveria bassiana, Metarhizium anisopliae, and Isaria fumosorosea on the whitefly Bemisia tabaci (Homoptera: Aleyrodidae) in different strata of bean

摘要

Beauveria bassiana, Metarhizium anisopliae?and?Isaria fumosorosea?are entomopathogenic fungi used as biological control agents for whitefly. They have been individually evaluated under laboratory, greenhouse and field conditions; however, there is little information on their comparative efficacy under greenhouse conditions particularly with respect to the height of the canopy in which they act. Mortality of eggs, first, second and third instar nymphs, pupae and adults were monitored on leaves located at three different heights in the canopy. The?Bemisia tabaci?population was homogeneously distributed in the tree strata of the plant and there was not any significant difference in mortality of the individuals for all life stages between the different strata.?M. anisopliae?was significant more effective against eggs, first, second and third instar nymphs and pupae, even under the adverse weather conditions in which the experiment was conducted; however,?B. bassiana?caused the greater mortality of adults. Our results indicate that mixed applications of?M. anisopliae?and?B. bassiana?could maximize the likelihood for control of all stages of?B. tabaci.