Compatibility of the insect pathogenic fungus Beauveria bassiana with neem against sweetpotato whitefly, Bemisia tabaci, on eggplant

Abstract

AbstractA study on the compatibility of the entomopathogenic fungus Beauveria bassiana (Balsamo) Vuillemin (Ascomycota: Hypocreales) with neem was conducted against sweetpotato whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), on eggplant. Initially, three concentrations of B. bassiana (106, 107, and 108 conidia ml−1) and three concentrations of neem (0.25, 0.5, and 1.0%) were used as individual treatments against B. tabaci. The highest concentration of B. bassiana yielded the highest B. tabaci egg (25.2%) and nymph mortalities (73.0%), but this was not significantly different from the mortalities caused by the 107 conidia ml−1 suspension. Similarly, the highest concentration of neem yielded the highest egg (27.3%) and nymph mortalities (75.5%), which was also not significantly different from the 0.5% suspension. Therefore, 0.5% neem was used along with 107B. bassiana conidia ml−1 suspension as an integrated pest management program against B. tabaci. The combination of B. bassiana and neem yielded the highest B. tabaci egg (29.5%) and nymph mortalities (97.2%), and the lowest LT50 (2.08 day) value. Moreover, an integrated combination of B. bassiana with neem caused 27.6 and 20.5% more nymphal mortality than individual treatments of B. bassiana and neem, respectively, 7 days post‐application. Thus, a combined application of an entomopathogenic fungus and a botanical insecticide may benefit from both, and it has proven effective for the control of B. tabaci on eggplant.