Hybridization of Neotyphodium endophytes enhances competitive ability of the host grass
Article first published online: 10 APR 2012
© 2012 The Authors. New Phytologist © 2012 New Phytologist Trust
Volume 195, Issue 1, pages 231–236, July 2012
How to Cite
Saari, S. and Faeth, S. H. (2012), Hybridization of Neotyphodium endophytes enhances competitive ability of the host grass. New Phytologist, 195: 231–236. doi: 10.1111/j.1469-8137.2012.04140.x
- Issue published online: 24 MAY 2012
- Article first published online: 10 APR 2012
- Received: 1 February 2012, Accepted: 29 February 2012
- intraspecific competition;
- •Associations with microbial symbionts may lead to niche differentiation of their host. Vertically transmitted Neotyphodium endophytes of grasses often hybridize in nature. Infection by these hybrid symbionts may result in different host–plant phenotypes from those caused as a result of infection by nonhybrid symbionts. Observations of wild Arizona fescue (Festuca arizonica) populations show that hybrid Neotyphodium-infected (H+) grasses dominate in resource-poor environments, whereas nonhybrid endophyte-infected (NH+) grasses dominate in environments with more resources. We studied the hypothesis that hybridization of endophytes increases stress tolerance of the host.
- •To test whether hybridization of Neotyphodium affects performance and competitive abilities of the host depending on resources, we conducted a glasshouse experiment where competition, nutrients and watering were manipulated.
- •H+ plants had greater wet biomass than NH+ and endophyte-free plants, when grown in competition, but only in low-water and low-nutrient treatments. By contrast, NH+ plants did not perform better than H+ or endophyte-free plants regardless of the treatment combination.
- •Our results suggest that hybridization of symbiotic Neotyphodium endophytes may increase competitive potential of the host in stressful environments and that this hybridization may be underlying niche expansion of Arizona fescue in the environments with low resources.