Wild and managed insect pollinators are essential for crop production, but may be experiencing unprecedented declines as a result of intensive agriculture and urbanization. The objective of our research is to examine agricultural practices and their effects on pollinators, providing information fundamental to the future of food production. Specifically, we are investigating the effects of new pest treatments on individual, colony health, and learning ability of pollinators, and comparing the diversity and abundance of wild bees in organic, conventional, and genetically modified agroecosystems. In this talk we report on findings of a laboratory study examining the effects of the two transgenic proteins, Cry 1Ac (Bacillus thuringiensis) and chitinase, and the new chemical pesticide imidacloprid on bumble bees. Six bumble bee colonies in each of three treatment groups and one control were fed honey bee collected pollen for 10 weeks with either no pesticide, Cry1Ac at 50 ng/g pollen, chitinase at 0.6 ug/g pollen, or imidacloprid at 10 ng/g pollen. For each treatment the level of pesticide was chosen to approximate concentrations that have been found in the pollen of genetically modified or chemically treated plants. Colonies were monitored for worker longevity, adult weight, brood development time, and number of eggs, larvae, pupae, workers, and reproductives. After two months of feeding, learning ability of similar age worker bees in each treatment was assessed using an artificial foraging array set-up. The ability of bees to distinguish between rewarding and unrewarding flowers and their ability to access a complex flower type was compared among treatments. The results of this experiment provide information on the effects of agriculture on wild and managed pollinators crucial for food production and ecosystem health.
Species 1: Hymenoptera Apidae Bombus occidentalis (bumble bee)
Keywords: Genetically modified, agriculture
The ESA 2001 Annual Meeting - 2001: An Entomological Odyssey of ESA