Intervarietal differences in nitrogen content and nitrate assimilation in wheat (Triticum aestivum L.) under salt stress

Effect of five NaCl salinity treatments (0, 50, 100, 200 and 300 mM) given at different growth and developmental stages on total N level and in vitro nitrate reductase activity (NRA) in leaves and roots of two wheat cultivars viz., Ghods and Boolani was studied in greenhouse conditions. In response to salinity treatments, total N concentrations and NO(3)(-) assimilation rates in Ghods, a salt-sensitive cultivar, were suppressed more than that of Boolani, a salt-resistant cultivar. However, not much differences in root N content were found between the cultivars. Our data suggest that NRA is affected under the influence of salt stress more than that of N concentration. In addition, there was no clear correlation between N levels and the activity of NR, particularly in leaves. The effect of salinity stress on N content and NRA depends on the cultivar, organ, developmental stage and degree of salt stress.