Antioxidant Genes in \u3ci\u3eApis mellifera\u3c/i\u3e, Their Implication in Pesticide Detoxification

The effect of pesticides on Apis mellifera mortality as well as their effect on the transcriptional regulation of antioxidant genes was the aim of this study. Unlike previous studies, the work here shows the combined effects of pesticides imidacloprid and coumaphos on worker bees at levels likely encountered by workers using both toxological and molecular analysis. Bee brood were collected from hives and incubated until hatching. The 1 day old bees were then segregated and subjected to varying concentrations of coumaphos and imidacloprid both independently and in concert. Workers from each treatment group were removed and stored in RNA-later until they were used for molecular analysis. The 10 antioxidant genes monitored here comprised of both primary and secondary antioxidants. Four of the secondary antioxidants used were seleno-like genes found in the genome. These showed differential expression throughout the bee’s development as well in the presence of pesticides

Effects of Coumaphos and Imidacloprid on Honey Bee (Hymenoptera: Apidae) Lifespan and Antioxidant Gene Regulations in Laboratory Experiments

The main objective of this study was to test comparatively the effects of two common insecticides on honey bee Apis mellifera worker’s lifespan, food consumption, mortality, and expression of antioxidant genes. Newly emerged worker bees were exposed to organophosphate insecticide coumaphos, a neonicotinoid imidacloprid, and their mixtures. Toxicity tests were conducted along with bee midgut immunohistological TUNEL analyses. RT-qPCR assessed the regulation of 10 bee antioxidant genes linked to pesticide toxicity. We tested coumaphos at 92,600 ppb concentration, in combination with 5 and 20 ppb imidacloprid. Coumaphos induced significantly higher bee mortality, which was associated with down regulation of catalase compared to coumaphos and imidacloprid (5/20 ppb) mixtures, whereas, both imidacloprid concentrations independently had no effect on bee mortality. Mixture of coumaphos and imidacloprid reduced daily bee consumption of a control food patty to 10 mg from a coumaphos intake of 14.3 mg and 18.4 and 13.7 mg for imidacloprid (5 and 20) ppb, respectively. While coumaphos and imidacloprid mixtures induced down-regulation of antioxidant genes with noticeable midgut tissue damage, imidacloprid induced intensive gene up-regulations with less midgut apoptosis

Evaluating Mating Control of Honey Bee Queens in an Africanize Area of Guatemala

Tests using mark-recapture of cordovan drones show that beekeepers in southwest Guatemala can control at least 70% of the matings of their queens by using drone flooding techniques. When Europeanderived stocks are used, such control should be sufficient to avoid most of the problems associated with Africanized honey bees. We assume that the beekeepers will monitor their colonies closely and requeen when necessary with marked queens derived from selected or imported breeding stock. With these practices beekeepers in Guatemala should be able to maintain bees more desirable than the highly Africanized bees they had previously.This is an article from American Bee Journal 133 (1993):207-211.</p