| Abstract Detail
Ecology Pittenger, Madison [1], Caudle, Keri L. [2], Baer, Sara G. [3], Johnson, Loretta C. [4], Maricle, Brian R. [5]. Herbivory preferences among ecotypes of big bluestem (Andropogon gerardii). Big bluestem (Andropogon gerardii), a dominant prairie grass, exhibits a wide distribution with several genetically distinct ecotypes. Each ecotype uniquely adapts to abiotic and biotic factors within its own environment. These adaptations may prove more or less desirable to herbivores in the area. For instance, plants adapted to areas with greater rainfall tend to grow larger than those adapted to drier conditions. However, wetter conditions might result in greater numbers of herbivores, so ecotypes adapted to wetter conditions might have evolved greater herbivore defense mechanisms; therefore, a trade-off may exist between drought resistance and herbivore resistance. We hypothesized that herbivores would display a preference for plants adapted to drier conditions. We tested this with feeding preference trials involving grasshoppers and leaves from five ecotypes of A. gerardii that represented plants adapted to wet and dry conditions. Scans of leaves before and after herbivory trials indicated 53 to 77 percent of leaf area remained, with the more mesic ecotypes being favored by herbivores. We also hypothesized that leaves with more tannins would be less preferable to herbivores. This was tested with measures of leaf tannin concentration from five ecotypes of A. gerardii from four common gardens across a precipitation gradient. Leaf tannin concentrations ranged from 0.19 to 3.93% of leaf dry mass, and were not different among ecotypes. However, there were site differences among leaves, indicating environmental influences on leaf tannin concentration. Ecotypes of A. gerardii are responsive to environmental factors involving herbivory, but were not related to leaf tannin concentrations. Log in to add this item to your schedule
1 - Fort Hays State University, Department of Biological Sciences, 600 Park St., Hays, Kansas, 67601, United States 2 - Fort Hays State University, Department of Biological Sciences, 600 Park Street, Hays, KS, 67601, USA 3 - Southern Illinois University, Department of Plant Biology and Center for Ecology, Carbondale, IL, 62901, USA 4 - Kansas State University, Biology, Ackert Hall Rm 232, Manhattan, KS, 66506-4901, USA 5 - Fort Hays State University, Department Of Biological Sciences, 600 Park St., Hays, KS, 67601-4099, USA
Keywords: tannins common gardens sand bluestem herbivory tolerance drought tolerance.
Presentation Type: Poster Session: P, Ecology Location: Exhibit Hall/Omni Hotel Date: Monday, June 26th, 2017 Time: 5:30 PM This poster will be presented at 6:15 pm. The Poster Session runs from 5:30 pm to 7:00 pm. Posters with odd poster numbers are presented at 5:30 pm, and posters with even poster numbers are presented at 6:15 pm. Number: PEC006 Abstract ID:169 Candidate for Awards:Ecological Section Best Undergraduate Presentation Award |