Research Accomplishment Reports 2011

Endophyte Effects on the Structure and Function of Tall Fescue Pasture

R.L. McCulley
Department of Plant and Soil Sciences

 

Non-Technical Summary

Endophyte infection in tall fescue can cause significantly alter nutrient cycling and soil characteristics in pastures of the southeast. The purpose of this study is to evaluate the geographic range over which these endophyte effects are observed and to determine whether climate plays a role in governing these effects.

2011 Project Description

Activities performed on this project in 2011 included: continuing to conduct a field experiment entitled Effects of Warming and Altered Precipitation Regime on Managed Grassland Structure and Function, completing a trace gas and plant production dataset from field plots of common toxic and novel endophyte-infected (E+) and endophyte-free (E-) tall fescue plots, training three graduate students on grass-endophyte symbioses and ecological effects, training/mentoring a postdoc on the subject, completing lab work to characterize the soil nutrient and microbial pools of E+ and E- stands from Indiana, initiating a new experiment on novel endophyte effects on litter decomposition rates, and initiating a new experiment exploring plant genotype x fungal endophyte genotype x climate interactions. We analyzed data from all but the newest of these projects. I mentored three graduate students, one postdoc, and three undergraduates.

Events that occurred were: four presentations on the results of this work were presented at two national meetings this year, and the climate change project served as a demonstration/field site for several small groups (international scientists, high school students, and UK College of Agriculture freshmen). Review services were provided for a nationally competitive panel (NSF), one Hatch proposal, one Canadian Research proposal, and >20 scientific manuscripts.

Products included creating new collaborations and writing competitive grants on the general topic. My group generated new fundamental knowledge about how tall fescue will respond to climate change and the dependency of these responses on endophyte infection status and endophyte genotype. I disseminated information on the topic of this KAES project through invited seminars (n=2) to college and university audiences and via presentations at the above mentioned conferences, field days, and workshops. I graduated my first PhD student on this topic, who is now employed as a visiting assistant professor at Berea College.

2011 Impact

This project has contributed to changing the conditions and knowledge about the topic (i.e., ecological effects of fungal endophyte symbioses in grasses) within the primary discipline and related fields. For example, we have shown that the fescue-endophyte story is not as straightforward as it is widely represented in the literature to be.

We have shown for the first time that novel endophytes have the ability to affect soil processes differently than the common toxic endophyte. We have generated new knowledge, as evidenced by several publications on the topic.

Through my graduate training, I have produced students that are currently using the scientific and teaching skills they acquired, in part, while in my program to their various positions. In addition, through my various presentations/demonstrations that I have made on this topic, I have educated the public, undergraduate and graduate students, and faculty from other areas on this particular topic.

2011 Publications

Iqbal, J., J.A. Siegrist, J.A. Nelson, and R.L. McCulley. (2012). Fungal endophyte infection increases carbon sequestration potential of southeastern U.S.A. tall fescue stands. Soil Biology & Biochemistry, 44:81-92

S.L. Hall. 2011. Restoration of tall fescue pastures to native warm season grasslands: Does a fungal endophyte symbiosis play a role in restoration success PhD Dissertation, University of Kentucky, 196 pp.

Hall, S.L., K. Clay, E. Koziol, and R.L. McCulley. 2011. Does endophyte status of tall fescue impact mycorrhizal colonization of native species commonly planted in grassland restorations Ecological Society of America Annual Meeting Abstracts, Austin, TX.

McCulley, R.L., J.A. Nelson, and A.E. Carlisle. 2011. Effects of elevated temperature and additional growing season precipitation on managed grassland carbon storage and flux. Ecological Society of America Annual Meeting Abstracts, Austin, TX.

Cooke, A.L., G.B. Brosi, J.A. Nelson, and R.L. McCulley. 2011. Climate change effects on forage quality of Kentucky hay fields. American Forage and Grassland Council Annual Meeting Abstracts, French Licks, IN.

Iqbal, J., J.A. Nelson, A.E. Carlisle, and R.L. McCulley. 2011. Influence of fungal endophyte genotypes on plant diversity and soil to atmospheric trace gas fluxes. Soil Science Society of America Annual Meeting Abstracts, San Antonio, TX.