Productivity, nutrient uptake and economics of grain amaranth (Amaranthus hypochondriacus L.) with N and Fe fertilization and planting techniques

A field experiment was conducted during rabi season of 2007–08 and 2008–09 at Instructional Farm, SD Agricultural University, Sardarkrushinagar (Gujarat), India to evaluate appropriate planting technique and N and Fe requirement of grain amaranth in light textured soil. Among the planting techniques, line sowing recoded significantly higher grain and stover yield of amaranthus. Nutrient content in grain and stover was maximum with line sowing. Highest total uptake of N, P and Fe was recorded with line sowing followed by paired row of planting. Yield of grain amaranths increased significantly with the application of 60 kg N ha⁻¹ then decreased gradually as crop received higher doses of N. Iron application did not have significant effect on yield during individual years but in pooled results it showed significant response and recoded higher yield. Iron application did not show significant effect in N and P content. Fe content and total uptake of N, P and Fe by the crop were significantly higher with the application of 10 kg FeSO₄ ha⁻¹. Highest net income ( 37648 ha-¹) and benefit: cost ratio (3.69) was associated with 60 kg N ha-¹ with 10 kg FeSO₄ ha⁻¹ with line sowing.