| Abstract: | Salinity is a major abiotic stress that limits the productivity of crops, particularly cereal crops, while decreasing nutrient availability, especially of nitrogen. An experiment was conducted to study the effects of salt stress i.e., S0, S1, and S2 (control, 1.09; 5; and 10 dS m?1)] and four different nitrogen (N) levels i.e., N0, N1, N2, and N3 (control, 175, 225, and 275 kg N ha?1)] on two maize hybrids, Pioneer 32B33 (salt tolerant) and Dekalb 979 (salt sensitive). The experiment was conducted in a wire house. The experiment was laid out with three factors in a completely randomized design. The plant tissue was analyzed for solute and ion contents. With the increase in salt stress and N rate, solute (i.e., glycinebetaine), protein, total soluble sugar, and total free amino acids accumulated in both hybrids. Nitrate (NO3) and nitrite (NO2) reductase activity decreased sharply at 10 dS m?1 compared to lower levels of salinity but it increased significantly with the addition of N. The uptake of potassium (K+), calcium (Ca2+), magnesium (Mg2+), N, and phosphorus (P) reduced significantly in shoots with increased salinity while the sodium (Na+) and chloride (Cl) contents were increased. It is concluded from the present study that at greater salinity level, hybrid Pioneer32B33 maintained statistically greater solute and ion contents excluding Na+ and Cl ions and significantly decreased enzyme activity. However, these parameters were increased by N rate. |
