The ecological consequences of hybridization of asexual microbial symbionts

University Of North Carolina Greensboro, Greensboro NC

Investigators

Abstract

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). Many new plant and animal species arise from hybridization between different species. Although less well-studied, microbial species also hybridize and create new genetic species and variants. All plants species harbor microbial partners, and these partners often dramatically alter plant growth and performance. For example, microbial partners in the roots of agricultural crop plants increase growth and yields. This project will examine the ecological consequences of hybridization among fungal endophytes that are microbial partners living inside grasses and that dramatically alter plant performance and resistance to drought and herbivores. This partnership or symbiosis has been manipulated to improve growth, competitiveness, and resistance to insects in the forage and turf grass industry. In native grasses, fungal endophytes appear to hybridize frequently to create new strains that can become common in nature. These new, hybrid strains of endophytes may affect growth and seed production and competitive abilities in ways very different than non-hybrid strains. This project will experimentally examine the role of hybridization of endophytes on growth and competitive abilities of two native grasses: sleepy grass (Achnatherum robustum) and Arizona fescue (Festuca arizonica). Soil water and nutrient conditions will be manipulated in greenhouse and field experiments to test the hypothesis that hybridization of endophytes increases the ability of the host grass to survive and compete better in harsh environmental conditions. This project has broad implications for efforts to conserve and restore native grasslands, and for rangeland management, since both study grasses are native species that are important to livestock grazing in the southwest USA. The research will also provide for collegiate and K-12 educational opportunities. This project will support undergraduate and graduate students to receive research training in plant and microbial ecology. Undergraduate students will be recruited from the University of North Carolina - Greensboro, with an emphasis on involving women and minorities. As part of this project, a summer internship for local K-12 teachers will be established in partnership with The Science Nature Center of Greensboro and North Carolina State Parks.