The reduced-risk insecticide azadirachtin poses a toxicological hazard to stingless bee Partamona helleri (Friese, 1900) queens

Abstract

Large-scale pesticide application poses a major threat to bee biodiversity by causing a decline in bee populations that, in turn, compromises ecosystem maintenance and agricultural productivity. Biopesticides are considered an alternative to synthetic pesticides with a focus on reducing potential detrimental effects to beneficial organisms such as bees. The production of healthy queen stingless bees is essential for the survival and reproduction of hives, although it remains unknown whether biopesticides influence stingless bee reproduction. In the present study, we investigated the effects of the biopesticide azadirachtin on the survival, behavior, morphology, development, and reproduction of queens of the stingless bee Partamona helleri (Friese, 1900). The neonicotinoid imidacloprid was used as a toxic reference standard. Queens were orally exposed in vitro to a contaminated diet (containing azadirachtin and imidacloprid) during development. Azadirachtin resulted in reduced survival, similarly to imidacloprid, altered development time, caused deformations, and reduced the size of the queens' reproductive organs. All of these factors could potentially compromise colony survival. Results from the present study showed azadirachtin posed a toxicological hazard to P. helleri queens.

Proteomic Profiling Analysis of Male Infertility inSpodoptera LituraLarvae Challenged with Azadirachtin and its Potential‐Regulated Pathways in the Following Stages

“…Azadirachtin was reported to be able to impair development of the reproductive system in several insect species, including Partamona helleri queens, Tuta absoluta , and Drosophila melanogaster . Moreover, azadirachtin‐induced imbalance in the titer of ecdysteroid and juvenile hormone could make great contributions to the abnormal development in reproductive system and have influences on reproduction via impairment of oogenesis and vitellogenesis, reducing mating probability and motility .…”

“…For insects, the reproductive ability was vital for species propagation and great potential as targets for insect control. Indeed, azadirachtin could have impacts on the reproductive ability of flies by regulating the yolk protein content in fat body and ovaries, postmating process of both sexes of flies, and the number of cysts and the apical nuclei position, reducing the size of the queens’ reproductive organs . However, the detailed mechanisms underlying such regulation were largely unknown.…”

Insights into the Toxicity and Degradation Mechanisms of Imidacloprid Via Physicochemical and Microbial Approaches

“…Apis mellifera LD 5048h = 0.0037 lg/bee Poses a major threat to bee biodiversity, affects the individual immunity of bees [41][42][43] Toxics 2020, 8, 0065 5 of 31…”

“…For instance, Apis mellifera is viewed as a pointer of classic ecotoxicology tests, and imidacloprid is highly toxic to it [41]. Indeed, the large-scale use of pesticides is the main reason for the decline in bee populations; pesticides pose a major threat to bee biodiversity by damaging the maintenance of bee ecosystems and by reducing agricultural productivity [42]. For example, bee farms near agricultural areas have a high mortality rate during pesticide use [56].…”

Epithelial remodelling of the midgut in the post-embryonic development of Partamona helleri (Apidae, Meliponini)

“…Partamona helleri , for example, can be found in Brazil, in the states of Bahia, Espírito Santo, Minas Gerais, Paraná, Rio de Janeiro, Santa Catarina and São Paulo (Camargo and Pedro 2013). Despite being an aggressive species, P. helleri plays an important economic role as a pollinator of a large number of plant species (Bernardes et al 2018). This ensures the maintenance and conservation of natural ecosystems and economically relevant agricultural systems (McGregor 1976;Camargo and Pedro 2013).…”