Efficacy of a new strain of beauveria bassiana against the melon fruit fly, zeugodacus cucurbitae (Diptera: Tephritidae)

Abstract

The melon fruit fly, Zeugodacus cucurbitae Coquillett (Diptera: Tephritidae) is an important pest in tropical and subtropical regions of the world. The biocontrol effect of Beauveria bassiana (Bals.) Vuill. (Hypocreales: Cordyciptaceae) BC-B1 strain on Z. cucurbitae was evaluated. One suspenso-emulsion (SE) formulation of B. bassiana was prepared and was applied against Z. cucurbitae under laboratory conditions. The results showed that the LC50 of BC-B1 on the adults and larvae of Z. cucurbitae were 0.65 x 105 and 1.08 x 105 conidia/mL, respectively. B. bassiana conidia were not affected by abamectin and imidacloprid at field dose, which is strong in compatibility. In comparison to using single biopesticide (B. bassiana), using the mixed formulation could improve efficacy. There were high synergistic interactions of B. Bassiana-abamectin and B. bassiana-imidacloprid to larvae of Z. cucurbitae. The larval mortalities reached 88.75%. The soil inoculation of B. bassiana is proved to be a great help to increase mortality of larvae. These results suggested that B. bassiana BC-B1 strain could be useful for control of Z. cucurbitae.