Effect of NaCl on growth,ion composition and ascorbic acid concentrations of capsicum fruit

Potted plants of Capsicum annuum, cultivar ‘Long Sweet Yellow’, were restricted to two fruits each and supplied with 0, 10, 25 and 50 mM NaCl. Chloride concentrations exceeded sodium concentrations in ripe fruit from all salt-treatments. The difference was 2.5-fold in ripe fruit from plants treated with 50 mM NaCl. Fruits from the 50 mM treatment were markedly lower in fresh weight and were of a more intense colour than control fruit. Fruit ripening was accelerated by all salt-treatments, but the fresh weight to dry weight ratio of ripe fruit was reduced; the reduction was in proportion to the stress applied.A significant correlation was found between fruit ascorbic acid and Ca^{2 +} concentrations. Fruit Ca^{2 +} was reduced by salinity, but the reduction was not in proportion to sodium chloride concentration. Additional calcium nitrate in the nutrient solution increased the Ca^{2 +} content and ascorbic acid concentration in fruit on control plants but not in fruit from plants treated with 50 mM NaCl. Instead, these fruit showed a marked increase in Na⁺.