Assesment of drought resistant of Quercus branti and Q. Libanii seedlings using growth, physiological and nutrient uptake

Drought is the one of the major environmental stresses that it has a negative effect on plant growth. The Zagros forests with Mediterranean climate are dry forests, So that, for this purpose, the effect of drought stress on growth and physiological traits and nutrient uptake in two species of Quercus (Brantii and Libani) were investigated. øFor doing this experiment, the treatment wase 4 levels includes of control and drought stress. The results showed that drought stress had negative effects on growth, morphological and physiological parameters of two oak species, so that most of parameters decreased but electrolyte leakage rate of organs were increased. Results of nutrient uptake also showed that K uptake rate of root and shoot was increased under drought stress. The results showed that stress tolerance index (STI) of Q. Brantii for all parameters except of fresh and dry weight of leaf were higher than Q. Libani. Overall, these results indicated that the Q. Brantii could show more resistant to drought stress than Q. Libani, which may be due to lower Na uptake rate of leaves and so Na/K ratio and number of leaf.