Journal or Publishing Institution: Universidade Federal de Viçosa
Author(s): Gomes, I.N.
Article Type: Report
Record ID: 808
Abstract: Pollination is one of the essential ecological services for the maintenance of natural and agrarian environments. Among the pollinators, bees represent a diverse group that plays a fundamental role in this process. The decline of bee populations has been reported, with the intensive use of pesticides being pointed as one of the main factors responsible for this impact. In Brazil, the stingless bee Melipona capixaba is threatened with extinction. Its region of occurrence is largely impacted by the presence of various agricultural crops and the use of agrochemicals. In this sense, the objective of this work was to evaluate the toxicity of the pesticides thiamethoxam, glyphosate and mancozeb on workers of M. capixaba and Apis mellifera. Survival bioassays were performed by contact and ingestion exposure at field doses and dilution of this dose to 1/10. The surviving bees of these bioassays were submitted to the flight test. Repellency bioassays were also performed. In the survival bioassays the two doses of the thiamethoxam insecticide in the two exposure routes, and the field dose of the herbicide glyphosate on ingestion exposure decreased the survival of the individuals of M. capixaba and A. mellifera. The two doses of the mancozeb fungicide decreased the survival of A. mellifera bees exposed by contact, however in the flight bioassays performed with the survivors of this route of exposure, these treatments caused changes in the flight capacity of both species. In the exposure by ingestion the field doses of the glyphosate herbicide caused losses in the flight of both species, as well as the field dose of the fungicide, only for A. mellifera. Finally, it was verified an absence of repellency of the pesticides tested for the two species, possibly leading to a high exposure of the workers during the foraging. These results suggest that the three pesticides tested have negative impacts on the population of the threatened stingless bee M. capixaba and on the A. mellifera species.
Citation: Gomes, I.N., 2017. Assessment of the potential effects of pesticides on bees of the species Melipona capixaba and Apis mellifera. Doctoral dissertation, Universidade Federal de Viçosa.
