Effect of nacl salinity on growth and distribution of sodium and some macronutrient elements in soybean plant

Two pot experiments were carried out with soybeans using vermiculite and water culture as growth media to study: a) the effect of NaCl salinity on the growth and cationic relations in the plant and b) the effect of NaCl elimination on the cationic relations in the salt-affected plants. The results obtained were as follows. 1. Salinity depressed the plant growth, particularly pods at the filling stage due to the low efficiency of pod yield production % (dry matter distribution %) in the salt-affected plants.2. In the salt-affected plants, the stems were found to be the major sink of accumulated sodium, while the leaves exhibited the lowest Na concentration among the different plant parts.3. After NaCl elimination from the growth medium, Na concentration in the salt-affected plants was markedly decreased particularly in the leaves and pods. In contrast, Na concentration in the shoots was slightly increased.4. Salinity generally increased the concentrations of K, Ca, and Mg in the leaves and decreased them in the roots and stems. However, short term salinization decreased the total uptake of K, Ca, and Mg by plant.5. Differences between control and salt affected plants in the content of macronutrients in different parts were generally less appreciable after NaCl elimination from the nutrient solution. Based on the above results, it is suggested that, irrigation of salt-affected soybean plants with fresh water at intervals may enable to alleviate the abnormalities in the cationic relations of the plants