Sulphur nutrition of crops with and without organic manures under intensive cropping

Abstract

A field experiment was conducted during pre-rainy season, rainy season (kharif) and winter season (rabi) of 1989-90 and 1990-91 to evaluate the productivity and fertility building under intensive cropping of rice (Oryza sativa L.) – potato (Solanum tuberosum L) – sesame (Sesamum indicum L). The productivity of rice and potato was maximum where these crops were fertilized with 75% (N, P and K @ 45, 10 and 19 kg/ha for rice; 75, 33 and 62 kg/ha for potato) of the recommended doses of N, P (through single super phosphate) and K (60, 13 and 25 kg/ha for rice; 100, 44 and 83 kg/ha for potato) in conjunction with farmyard manure @ 10 t/ha. Sesame grown on residual fertility recorded maximum seed yield (1.4 t/ha) in the treatment receiving 75% of the recommended fertilizer applied to both rice and potato along with incorporation of crop residues of each crop in the sequence. Exclusion of single super phosphate having 12% S either from potato or from rice reduced the productivity of all the 3 crops. Nutrient uptake was maximum where both rice and potato were fertilized with 100% of the recommended doses of N, P (as single super phosphate) and K. Total N, and the available P, K and S status of the soil improved when both rice and potato were fertilized with 75% of the recommended fertilizer along with farmyard manure @ 10 t/ha or incorporation of crop residues. Negative balance of S was recorded under the treatments receiving no single super phosphate, farmyard manure or crop residues. Application of farmyard manure @ 10 t/ha to both rice and potato in conjunction with 75% (N, P and K @ 45, 14 and 19 kg/ha in rice; 75, 33 and 62 kg/ha in potato) of the recommended fertilizer was more remunerative than that of 100%.