Effects of Increasing Water Stress on Simulated Swards of Festuca arundinacea Schreb under Wind Tunnel Conditions

The effects of increasing water stress on water relations, leaf conductance, leaf extension and leaf rolling of Festuca arundinacea in sward (I m2) were investigated under wind tunnel conditions. The plants were grown in a container 60 cm deep and the experiment was conducted over a 36 d period. Upon cessation of watering (day 11), leaf extension and conductance were affected. Within 8 d, the onset of leaf rolling helped to reduce transpiration and to maintain leaf water potential. Nocturnal recovery of turgor potential helped in maintaining leaf extension at a moderate level and in the final 5 d water and osmotic potentials dropped sharply as leaf rolling became more acute and leaf extension stopped. The grass combines various morphological and physiological mechanisms to prevent water losses and maintain growth.