Growth and physiological responses of tree species in salinized soil treated with amendments

The study aimed to evaluate the effect of amendments on the reclamation of a saline-sodic soil and on growth and physiological responses of native species of trees from Caatinga ecosystem. Two experiments were carried out in a greenhouse, in a completely randomized design. In first experiment, five treatments of soil reclamation were evaluated with four replications. In the second experiment the treatments were arranged in a factorial scheme 5 x 4, related to the native species of trees from Caatinga ecosystem and five treatments of reclamation evaluated in the first experiment with three replications. The application of amendments, especially elemental sulfur, decreased salinity and sodicity of salinized soil, favoring the growth and dry matter production of plants. The Caesalpinia ferrea specie was the one that was more tolerant to excess of salts and sodium. Excess of salts and sodium in the soil increased the concentration of sodium and sodium/potassium ratio in the shoots and decreased stomatal conductance and intercellular CO2 concentration in the leaves.