Indução do parasitoidismo por Myrmosicarius grandicornis, Borgmeier, 1928 (Diptera : Phoridae) em Atta sexdens (Linnaeus, 1758) (Hymenoptera : Formicidae) em condições de laboratório

Abstract

The interaction between ants and their natural enemies is a relevant field of ecology, especially in contexts where parasitoids act as natural agents of population control. This approach has gained increasing interest as a sustainable alternative to chemical pesticides, given their environmental and economic impacts. Among ant pest groups, leaf-cutting ants, particularly Atta sexdens (Linnaeus, 1758) (Hymenoptera: Formicidae), stand out for their complex social organization and the significant damage they cause to agriculture and the environment. In this study, parasitism rates in leaf-cutting ants artificially exposed to the phorid fly Myrmosicarius grandicornis Borgmeier, 1928 (Diptera: Phoridae) were evaluated, considering variables such as mortality, survival time, and head capsule size. Collections were carried out at three sites in São Cristóvão, Sergipe State, Brazil, between February and June 2025, totaling 360 ants and 26 phorid flies. Ants were equally divided into two groups (control and treatment). The experiments were conducted under controlled conditions, with direct exposure of ants to phorids for 90 minutes in entomological cages, at a ratio of five ants per phorid, and subsequently stored in a B.O.D. chamber and monitored for 15 days. Significant differences were observed in parasitism rates between the treatment and control groups (p = 0.04), in addition to higher mortality and shorter survival time in the exposed group (p = 0.04), as well as a smaller average head capsule size in the treatment group (p < 0.01). These findings reinforce the potential of phorids as biological control agents and contribute to the understanding of parasitoid–host dynamicsin leaf-cutting ant systems. The study highlights the importance of integrated and ecologically viable strategies in pest management, emphasizing the use of natural enemies as a promising alternative.