Do Endophytes help with Resistance to Drought and Herbivory in Ammophila breviligulata?

Abstract

The dunes of the East Coast and of the Great Lakes are dominated by Ammophila breviligulata, also known as American beach grass. Previous experiments completed on the species determined that Ammophila originating on the East Coast (Cape genotype) was infected with Acremonium typhinu, an endophyte previously known to infect forage and turf grasses (Halisky and White 1991). Interesting enough, research currently being conducted has shown that native Michigan genotypes are not infected (Emery, Rudgers, unpublished data). Through our research we found that Ammophila that had been cultivated in greenhouses had been planted by many National and State Parks. The greenhouse supplying Ammophila to the parks was selling two different genotypes: the Michigan genotype grown from local plants, and a Cape Genotype developed by the USDA Cape May Plant Materials Center. These populations originated in New Jersey. Thus, the parks may have been unintentionally introducing a non-native endophyte, which could have yet unknown results. In this experiment we used 2 different source populations of Ammophila; Cape, and native Michigan plants from Grand Mere State Park in SW Michigan (approximately 42.00N, 86.50W). For this study I used a combination of feeding trials and greenhouse experiments aimed to answer the following questions: 1. Do fungal endophytes provide protection from herbivores or drought? 2. Do they provide protection when both are present? 3. Do endophytes increase competitive ability of plants?