Lethal and sublethal toxicities of acetogenin-based bioinsecticides on Ceratitis capitata and the parasitoid Diachasmimorpha longicaudata

Abstract

In this study, was evaluated the action lethal and sublethal of three formulations of Annona species extracts (A. mucosa, A. muricata and A. sylvatica) on adults of Ceratitis capitata (Wiedemann, 1852) (Diptera: Tephritidae) and yours parasitoid Diachasmimorpha longicaudata (Ashmead, 1905) (Hymenoptera: Braconidae). In addition, the efficacy of the selected toxic bait formulations was evaluated by mixing them with different food attractants (Anamed™, 3% Biofruit and 7% sugarcane molasses). From the use of the discriminatory concentration (2000 mg L-1), only A. mucosa caused mortality of C. capitata of more than 85% in ingestion and topical application bioassays, equivalent a spinosyn-based insecticide (control positive). In toxic bait formulation with the tested food attractants, the extracts had a residual effect (mortality ≥80% C. capitata) up to 14 days after applying treatments (DAAT) in the absence of rain. Based on the LC90 (1984.20 mg L−1) values estimated from the concentration-response curves for C. capitata, A. mucosa caused less than 40% adult mortality of the parasitoid D. longicaudata in the ingestion bioassay. However, both treatments showed no sublethal effects (parasitism reduction) over time. In addition, in bioassays with and without choice, there was a significant reduction in the number of punctures and galls caused by females and larvae of C. capitata, respectively, in grape berries in the presence of dry residues of all evaluated treatments. The A. mucosa seed extract was considered the most promising product for use in C. capitata management programs, particularly in organic-based systems, due to its selectivity to D. longicaudata.