Nitrogen Nutrition Effects on Growth, Protein and Oil Quality in Soybean (Glycine max) Genotypes under Saline Conditions

Nitrogen (N) application affects crop growth and development even under saline condition. This study compared the effects of nitrogenous fertilizer on growth, biochemical activities, proteins and oil quality of soybean (Glycine max L.) genotypes under saline conditions. The experiment was comprised of salinity levels (7.5 and 15 dS m(-1) including control) and two nitrogen rates viz. 25 and 50 kg ha(-1) using calcium nitrate and ammonium sulphate as a source for NO3- and NH4+. Soybean growth significantly reduced under adverse saline conditions while N application increased the plant biomass. The results indicated that the application of nitrogen fertilizer in both forms significantly increased the shoot and root fresh as well as dry weights, reducing the leaf Na+ and enhancing K+ concentration under normal and saline conditions. Protein and oil contents were also improved by nitrogen nutrition which were significantly reduced by salinity. It was concluded that soybean accession 2429-3130 and 3702 had better biomass production, protein content, oil percent and K+ contents through N application then Lochlon and Ajmari under both saline and non-saline conditions. Comparing the N sources impact the application of N in the nitrate form was more effective under salt stressed conditions. (C) 2020 Friends Science Publishers