Wheat yield, some physiological traits and nitrogen use efficiency response to nitrogen fertilization under salinity stress

In order to assess the effects of salinity on yield, physiological parameters and nitrogen use efficiency of winter wheat (Triticum aestivumL.) an experiment was conducted with two cultivars (Bam and Toos) and three salinity levels, viz., 1.3, 5 and 10 dS m−1in 2008 and 2009, using a randomized factorial design with 3 replications. Results showed that the effect of salinity stress on physiological traits such as activity of superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX), and grain yield can be altered by application of 100 and 150 kg N ha−1. There was positive relationship between nitrogen application and salt tolerance. The salt-tolerant genotype exhibited maximum value for NUE, biochemical and yield characteristics at 100 kg N/ha than that of salt-sensitive genotype. As a result, an increase in nitrogen application played a key role in the ability of wheat cultivars to tolerate salinity damage on antioxidant enzymes and yield.