Impact of integrated nutrient management on soil fertility and yield of onion (Allium cepa) on an alluvial soil

A field experiment was conducted during rabi season of 2015-2017 at Panwari village of Agra district with a view to investigate the effect of integrated nutrient management on soil fertility, productivity and uptake of nutrients by onion (Allium cepa). Eight treatments were evaluated in randomized block design with three replications. Results indicated that the availability of N (222.0 kg ha-1), P (13.1 kg ha-1), K (150 kg ha-1) and Zn (0.55 mg kg-1) was improved with the conjoint use of organics and fertilizers. However use of 75% NPK along with 40 kg S ha-1 resulted in substantial increase in sulphur status of soil (18.0 kg ha-1). Minimum amounts of these nutrients in post harvest soil were recorded in control. Application of 75% NPK + 10 t FYM ha-1 significantly increased the growth, yield attributes, bulb yield ( 34.02 t ha-1) and dry matter yield of bulb (5.34 t ha-1). The increase in bulb yield due to 75% NPK + 40 kg S ha-1) was 44.6 % over control. The content and yield of protein also improved with conjoint use of NPK fertilizers and FYM and sulphur. The minimum values of content and yield of protein were recorded in control. The uptake of nutrients increased with increasing level of NPK fertilizers and showed further increase in the presence of 10t FYM ha-1. The residual soil fertility was recorded minimum under control treatment.