Mediterranean and Continental Tall Fescue: I. Effects of Endophyte Status on Leaf Extension, Proline, Mono‐ and Disaccharides, Fructan, and Freezing Survivability

Abstract

ABSTRACTTall fescue [Festuca arundinacea Schreb. syn. Lolium arundinaceum (Schreb.) Darbysh.] is widely used for hay and pasture in the Eastern regions of the United States, with new types of Mediterranean tall fescue possessing superior growth under cool growing conditions. However, they do not survive Midwestern winters. To date, little research has examined the role of endophyte infection on the ability of tall fescue to grow under cold conditions or survive freezing conditions. This study's objectives determined the endophyte's role in tall fescue growth and production of metabolites for nonfreezing conditions. Additionally, the role of endophyte infection on the ability of plants to survive freezing temperatures was determined. This experiment used five genotypes of tall fescue. Half of the plants from each genotype were endophyte infected (E+), with the remaining genotypes being endophyte free (E–). We report for the first time the effects of endophyte status on proline, simple sugars, and fructan accumulation when plants were grown under cold, nonfreezing temperatures and the survivability at various freezing temperatures. Endophyte removal only affected fructan concentrations at 4.5°C; however, plant genotype affected leaf extension rate, proline, sugars, and fructan concentration. The freezing test found no effect of the endophyte on tiller survival, while plant genotype was significant. These data indicate that endophyte removal has little influence on the measured traits, and plant genotype is more critical for survival under cold conditions.