INFLUENCE OF PHOSPHORUS, SULPHUR AND BORON ON GROWTH, YIELD, NUTRIENT UPTAKE AND ECONOMICS OF RAPESEED (Brassica Campestris L. VAR. YE LLOW SARSON)
A field experiment comprising three levels each of phosphorus (0, 30 and 60 kg P2O5 ha-1) and sulphur (0, 20 and 40 kg S ha-1) and two levels of boron (0 and 1 kg B ha-1) was conducted during the winter seasons for two consecutive years of 2007-08 and 2008-09 at farmers field of Pingla block in Pashcim Medinipur district of West Bengal to study the contribution of these nutrients in improving yield components and yield of rapeseed crop [Brassica campestris var yellow sarson] cv. ‘B-9’ on medium deep loam soil having medium in available P and S. The experiment was carried out in a factorial randomised block design with three replications. The results revealed that successive increase in P, S and B levels increased yield attributes and seed yield of yellow sarson crop. The increase in seed yield was significant up to 60 kg P2O5 ha-1 and 40 kg S ha-1 while uptake of P and S was significant up to 60 kg P2O5 ha-1 and 20 kg S ha-1. Seed-yield response to tested different levels of P and S was found quadratic. Based on the response equation, optimum dose of P2O5 was 48.1 kg ha-1 and response was 8.3 kg seeds kg-1 P2O5. Corresponding figures for S application were 27.3 kg S ha-1 and 13.5 kg seed kg-1 S. Net returns were the maximum with 60 kg P2O5 ha-1 (Rs 40852.75 ha-1) and 20 kg S ha-1 (Rs 38477 ha-1), whereas benefit: cost ratio was the highest with 30 kg P2O5 ha-1 (2.87) and 20 kg S ha-1 (2.48). Boron application also recorded marked improvement in seed yield (14.38%), uptake of P (12.75%), S (12.78%) and net returns (13.9%) and benefit: cost ratio (7.11) as compared to control.