Effects of sodium chloride on tobacco plants.

The effect of salinity on the growth and ion concentrations in a number of tobacco cultivars is described. Sodium chloride, at a concentration of 200 mol m^-3, hardly affected the fresh weight, but significantly reduced the dry weight. The difference in the response of fresh and dry weights to salt was due to a change in succulence (water per unit leaf area); the latter increased with increasing leaf Na⁺ and Cl^- concentration. Under saline conditions, increasing the external Na⁺ Ca^- ratio by decreasing the Ca²⁺ concentration increased the accumulation of Na⁺ and Cl^- into the leaf tissue. [ABSTRACT FROM AUTHOR]