Leaf Water Potential, Stomatal Resistance, and Photosynthetic Response to Water Stress in Peach Seedlings

Abstract

Individual groups of peach (Prunus persica [L.] Batsch) seedlings stressed to -17, -26 and -36 bars recovered to control levels within 1, 3, and 4 days, respectively. Stomatal resistance was significantly correlated with both leaf water potential and net photosynthesis. In seedlings stressed to -52 bars, leaf water potential and stomatal resistance recovered sooner than net photosynthesis, despite recovery of 0(2) evolution at a rate similar to leaf water potential. Therefore, some nonstomatal factor other than reduction in photochemical activity must be responsible for the lag in recovery of CO(2) assimilation following irrigation.