Glyphosate affects the larval development of honey bees depending on the susceptibility of colonies

VAZQUEZ D; ILINA, N; PAGANO, E; ZAVALA, J; , FARINA WM; FARINA WALTER M.

PLOS ONE

PUBLIC LIBRARY SCIENCE

Lugar: San Francisco; Año: 2018

1932-6203

As the main agricultural insect pollinator, the honey bee (Apis mellifera) is exposed to anumber of agrochemicals, including glyphosate (GLY), the most widely used herbicide.Actually, GLY has been detected in honey and bee pollen baskets. However, its impact onthe honey bee brood is poorly explored. Therefore, we assessed the effects of GLY on larvaldevelopment under chronic exposure during in vitro rearing. Even though this proceduredoes not account for social compensatory mechanisms such as brood care by adult workers,it allows us to control the herbicide dose, homogenize nutrition and minimize environmentalstress. Our results show that brood fed with food containing GLY traces (1.25±5.0mg per litre of food) had a higher proportion of larvae with delayed moulting and reducedweight. Our assessment also indicates a non-monotonic dose-response and variability inthe effects among colonies. Differences in genetic diversity could explain the variation insusceptibility to GLY. Accordingly, the transcription of immune/detoxifying genes in the gutsof larvae exposed to GLY was variably regulated among the colonies studied. Consequently,under laboratory conditions, the response of honey bees to GLY indicates that it isa stressor that affects larval development depending on individual and colony susceptibility.