Effect of phosphorus and sulphur on yield attributes, yield, nodulation and nutrient uptake of green gram [Vigna radiate (L.) wilczek]

Abstract

Field experiments were conducted during pre kharif 2010, 2011 and 2012 to study the effects of phosphorus and sulphur on yield parameters, yield, nodulation and nutrient uptake of green gram. The experiment was laid out in a factorial randomized block design with three replications having eight treatment combinations viz. four levels of sulphur (0, 20, 40, and 60 kg ha-1) as factor A and two levels of phosphorous (30 and 60 kg ha-1) as factor B. Experimental results revealed that yield attributing characters and seed yield of green gram were significantly influenced by phosphorus, sulphur and interaction effects of these two factors. Application of higher dose of phosphorus (60 kg ha-1) and increasing levels of sulphur up to 40 kg ha-1proved to be the best in improving the yield attributing characters and seed yield (1.62t ha-1)of green gram. Sulphur applied beyond 40 kg ha-1could not increase the parameters further. Application of sulphur 20 kg ha-1 significantly increased the active nodule no. and nodule dry weight of green gram and there after applied S beyond 20 kg ha-1the mean nodule production reached a more or less plateau pattern and application of lower dose of phosphorus without sulphur drastically reduced the nodule dry weight. Interaction of higher dose of phosphorus and higher dose S found to have a negative impact on yield. Application of varying levels of phosphorus and sulphur significantly improved the nutrient uptake by green gram in a sulphur deficient soil. Sulphur acted synergistically with nitrogen and increased the uptake of other nutrients. Application of 60 kg P205 ha-1 and 40 kg Sha-1 proved to be most economic in green gram with NPV 4.59.