Ameliorative Effects of Nitrogen Application on Vegetative Growth and Productivity in Genotypes of Ragi (Eleusine coracana Gaertn.) under Saline Conditions

Abstract

Background: Salinity and low soil nitrogen availability are important growth limiting factors for most crops. The proper use of N fertilizer is not only important for growth but it may also alter the salinity tolerance of plants depending on the level of salinity. Methods: The present study was undertaken to determine the interactive effects of N nutrition and saline irrigations (3, 6, 7.2, 10, 12 and 14 dSm-1) on growth and grain productivity in two varieties of finger millet viz. VL-315 and Local Hills. Different growth and productivity parameters (like plant height, dry weight of shoot, root and leaves, dry weight of panicle/plant, no. of grains, grain yield/plant etc.) adversely affected by saline irrigations, however, nitrogen nutrition minimized at different levels of salinity. Result: The positive response of nitrogen was comparatively higher at lower salinity levels (3-7.2 dSm-1) as well as at control than higher salinity (10-14 dSm-1). The effect of salinity was lower in cv. VL- 315 than Local Hills, but the interactive effects of N nutrition and salinity also enhanced the dry weight of shoot, root, leaves, dry weight of panicles and grains/plant. It is probable that N nutrition had enhanced assimilation of NO3-1-N, through the activity of NRA which further increased total nitrogen and protein content in leaves, hence, enhanced growth, biological and grain yield in both cultivars.