Leaf characteristics associated with drought resistance in tall fescue cultivars

Knowledge of leaf features associated with turfgrass performance during drought is important for improving drought resistance. The objective of this study was to determine major leaf characteristics that could contribute to the maintenance of quality turf for tall fescue (Festuca arundinacea Schreb) exposed to drought stress. Twelve tall fescue cultivars were grown in soils maintained well watered by daily irrigation or under drought stress by withholding irrigation for 30 d in a greenhouse. Several drought stress indicators, including turf quality, leaf relative water content (RWC), and cell membrane stability expressed as electrolyte leakage (EL), and morphological, anatomical, and physiological characteristics of leaves were examined. Turf quality, RWC, and cell membrane stability decreased dramatically during drought stress for all 12 cultivars. Generally, 'Kentucky-31' was the most resistant to drought stress, 'Coyote' was the most sensitive, and the others were intermediate. Regression analysis of turf quality and various leaf characteristics for all 12 cultivars showed that turf quality under drought stress was related positively to leaf thickness, epicuticular wax content, and tissue density but negatively to stomatal density and leaf width.