Fungivorous mites enhance the survivorship and development of stingless bees even when exposed to pesticides

Abstract

Stingless bees are the largest group of eusocial bees in the world. They play an essential role as crop pollinators and have been considered for inclusion in pesticide risk assessments (RAs). Beyond the mutualism involving stingless bee larvae and fungi, the fungivorous mite Proctotydaeus (Neotydeolus) alvearii proved to be interesting for studies of associations with stingless bees. Their presence is related to colony strength and health, showing a permanent-host-association level. Here, we tested whether the coexistence with P. (N.) alvearii affects stingless bee larvae survivorship and development, including when fed pesticide-dosed food. We chose dimethoate, the reference standard for toxicity tests, and thiamethoxam, widely used in neotropical crops and listed to be reassessed in RAs. Bees associated with the mites showed higher larval survivorship rates, even in the dosed ones, and revealed changes in the developmental time and body size. Our study represents the first approach to stingless bee responses to the coexistence of fungivorous mites inside brood cells, leading us to believe that these mites play a beneficial role in stingless bees, including when they are exposed to pesticides.

Further evidences of an emerging stingless bee-yeast symbiosis

“…SDCP2 through the production of lovastatin and monascin, respectively ( Paludo et al, 2019 ). More recently, Rosa-Fontana et al (2022) reported the presence of fungivorous mites in brood cells of the Scaptotrigona postica , which might be involved in controlling the multiplication of both mutualistic and opportunistic fungi in the brood cell favoring the larval development of this SB.…”