Fig. 4 Carbon isotope discrimination (
), internal substomatal [CO2] (Ci), and water-use efficiency given as leaf photosynthetic assimilation (Aa, leaf area basis) divided by stomatal conductance (gs) of tall fescue Kentucky 31 (K-31) populations selected for high and low . Plants were grown under greenhouse conditions and data averaged across well-watered and polyethylene glycol stress treatments. The bar is the LSD at
