Title: | Pollen defenses negatively impact foraging and fitness in a generalist bee (Bombus impatiens: Apidae) |
Author(s): | Brochu KK; van Dyke MT; Milano NJ; Petersen JD; McArt SH; Nault BA; Kessler A; Danforth BN; |
Address: | "Department of Entomology, Penn State University, University Park, PA, USA. kkb90@psu.edu. Department of Entomology, Cornell University, Ithaca, NY, USA. kkb90@psu.edu. Department of Entomology, Cornell University, Ithaca, NY, USA. Minnesota Department of Natural Resources, St. Paul, MN, USA. Department of Entomology, Cornell AgriTech, Cornell University, Geneva, NY, USA. Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY, USA" |
DOI: | 10.1038/s41598-020-58274-2 |
ISSN/ISBN: | 2045-2322 (Electronic) 2045-2322 (Linking) |
Abstract: | "Plants may benefit from limiting the community of generalist floral visitors if the species that remain are more effective pollinators and less effective pollenivores. Plants can reduce access to pollen through altered floral cues or morphological structures, but can also reduce consumption through direct pollen defenses. We observed that Eucera (Peponapis) pruinosa, a specialist bee on Cucurbita plants, collected pure loads of pollen while generalist honey bees and bumble bees collected negligible amounts of cucurbit pollen, even though all groups of bees visited these flowers. Cucurbit flowers have no morphological adaptations to limit pollen collection by bees, thus we assessed their potential for physical, nutritional, and chemical pollen traits that might act as defenses to limit pollen loss to generalist pollinators. Bumble bee (Bombus impatiens) microcolonies experienced reduced pollen consumption, mortality, and reproduction as well as increased stress responses when exposed to nutritional and mechanical pollen defenses. These bees also experienced physiological effects of these defenses in the form of hindgut expansion and gut melanization. Chemical defenses alone increased the area of gut melanization in larger bees and induced possible compensatory feeding. Together, these results suggest that generalist bumble bees avoid collecting cucurbit pollen due to the physiological costs of physical and chemical pollen defenses" |
Keywords: | "Animals *Appetitive Behavior Bees/classification/*physiology Behavior, Animal Cucurbita Female Flowers/anatomy & histology New York *Plant Defense Against Herbivory *Pollen *Pollination;" |
Notes: | "MedlineBrochu, Kristen K van Dyke, Maria T Milano, Nelson J Petersen, Jessica D McArt, Scott H Nault, Brian A Kessler, Andre Danforth, Bryan N eng Research Support, Non-U.S. Gov't England 2020/02/23 Sci Rep. 2020 Feb 20; 10(1):3112. doi: 10.1038/s41598-020-58274-2" |