Wheat growth as affected by nitrogen type, PH and Salinity. I. Biomass production and mineral composition

The interactions among the form of N supplied (ammonium or nitrate), NaCl concentration, and pH of the nutrient solution were studied on wheat (Triticum aestivum L. cv. Barkai) grown hydroponically. Plant growth was affected by increasing NaCl concentration from 0 to 100 mM. Increasing the pH from 5 to 8 resulted in reduced growth of ammonium-fed plants, but not of nitrate-fed plants, at all concentrations of NaCl applied. Potassium concentration in the shoot was inversely correlated with Na, but directly correlated with shoot dry weight. These correlations were affected, however, by the form of N in the nutrient media. The sensitivity of ammonium-fed plants to NaCl may be due mainly to the decreased concentration of K in the shoot.