Percentage variation in the drought stress treatment (irrigation 0% of field capacity) with respect to the control (irrigation 0% of field capacity) for selected photosynthesis (A = net photosynthesis; g_s = stomatal conductance to water vapour; E = leaf transpiration; Ci/Ca = ratio between stomatal and ambient CO₂ concentration; WUE = Water Use Efficiency), and fluorescence parameters (ΦPSII = effective quantum efficiency of PSII; qP = photochemical quenching; qNP = non photochemical quenching; ETR = electron transport rate; F_v/F_m = maximum quantum yield of PSII), measured on Tietar and DKC6575 at T2 (after 20 d without irrigation) in the field experiment.

<p>Percentage variation in the drought stress treatment (irrigation 0% of field capacity) with respect to the control (irrigation 0% of field capacity) for selected photosynthesis (A = net photosynthesis; g_s = stomatal conductance to water vapour; E = leaf transpiration; Ci/Ca = ratio between stomatal and ambient CO₂ concentration; WUE = Water Use Efficiency), and fluorescence parameters (ΦPSII = effective quantum efficiency of PSII; qP = photochemical quenching; qNP = non photochemical quenching; ETR = electron transport rate; F_v/F_m = maximum quantum yield of PSII), measured on Tietar and DKC6575 at T2 (after 20 d without irrigation) in the field experiment.