Effect of intergrated nutrient management on root growth of wheat in a rice-wheat cropping system

The experiment was laid out in randomised block design with three replications during 1997–98. The treatments were combinations of organic and inorganic fertilizers. In rice, inorganic fertilizers were tested at 50, 75 and 100 per cent of the recommended dose of NPK (80:60:40 kg) as compared to substitution of 50 per cent and 25 per cent N through organic sources viz., green manure, FYM and rice-straw while in wheat 50,75 and 100 per cent of recommended NPK ferti lizer (100:50:30 kg) was used. The treatment having 50 per cent NPK. plus 50 per cent N through green manure (Gratolaria juncea) in kharif and 100 per cent NPK in rabi resulted in highest yield and maximum root length density (0–24 cm depth), root volume and root dry weight (0–36 cm depth), whereas it was lowest in control.