Nitrogen uptake efficiency of finger millet grown in hydroponic culture

The optimum nitrogen requirement along with nitrogen uptake efficiency of finger millet (Eleusine coracana) for obtaining plants of a high phenotypic quality was studied in this research using hydroponic culture. 20 days old seedlings were transferred in nutrient solution containing all the essential macro and micro nutrients. Plants were subjected to three treatments of nitrate viz. 0.05 mM, 0.1 mM and 0.5 mM by dissolving it in the nutrient solution. Plants grown in nutrient solution devoid of nitrate were treated as control. Plants grown in 0.5 mM nitrate conc. attained more height compared to other low nitrogen treatments (0.1 mM and 0.05 mM). Similarly plants of 0.5 mM nitrate treatments possessed more number of lateral roots, surface area of leaves, dry weight of plants and chlorophyll content compared to other low nitrogen treatments. Specific activity of nitrate reductase in plants treated with 0.5 mM concentration was found nearly 3 times higher than that of control plants; similarly, specific activity of nitrite reductase in 0.5 mM treated plants was also high compared to other low nitrogen treatments followed by control. The results of the present investigation therefore indicate that nitrogen uptake efficiency as revealed by the activities of nitrate reductase and nitrite reductase was high in 0.5 mM nitrate treatment. It also shows that 0.5 mM nitrate is optimum nitrogen concentration for the growth of finger millet in hydroponic condition.