Changes in photosynthetic parameters and nutrient distribution of olive plants (Olea europaea L.) Cultivar 'chondrotia chalkidikis' under NaCl, Na2SO4, and KCl salinities

The effect of NaCl, Na2SO4, and KCl on growth, nutrient distribution, photosynthetic parameters and leaf water potential of young olive (Olea europaea L. cv. 'Chondrolia Chalkidikis') plants. was studied under greenhouse conditions. The plants originated from leafy cuttings, were grown in a 1:1 sand:perlite mixture and irrigated with half strength Hoagland's nutrient solutions containing 0, 30, 60, 90, 120 and 150 meq.L-1 NaCl, Na2SO4, or KCl. The experiment terminated after 96 days when toxicity symptoms in leaves were obvious at the highest saline treatments. Salinity significantly reduced shoot growth after 55-60 days, but the dry weight of the plants was not affected. Net photosynthetic rate and stomatal conductance were also significantly reduced but the internal CO2 concentration remained constant with increasing concentrations of salts. Salinity also brought about a significant reduction in chlorophyll concentration and water potential. Salt toxicity followed the order KCl > Na2SO4 > NaCl. In general. salinity decreased the leaf concentration of N, P, K, Ca, Mg, Fe, Mn, Zn and B, and increased that of Na (NaCl > Na2SO4) and Cl (KCl > NaCl). The percentage of total Na and Cl plant content in leaves remained however lower than that of shoots and roots.