SULFUR NUTRITION OF CROPS WITH AND WITHOUT ORGANIC MANURES UNDER INTENSIVE CROPPING

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 ri ce (Oryza sativa L.)-potato(Solanum tuberosum L)-sesame (Sesamum indic um L). The productivity of rice and potato was maximum where these cro ps were fertilizer with 75% (N, P and K @ 45, 1 0 and 19 kg/ha for ric e; 75, 33 and 62 kg/ha for potato) of the recommended doses of N, P (t hrough single superphosphate) and K (60,13 and 25 kg/ha for rice; 100, 44 and 83 kg/ha for potato) in conjunction with farmyard manure @ 10 tonnes/ha. Sesame grown on residual fertility recorded maximum seed yi eld (1.4 tonnes/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 pro ductivity of all the 3 crops. Nutrient uptake was maximum where both r ice and potato were fertilized with 100% of the recommended doses of N , P (as single superphosphate) and K. Total N, and the available P, K and S status of the soil improved when both rice and potato were ferti lized with 75% of the recommended fertilizer along with farmyard manur e @ 10 tonnes/ha or incorporation of crop residues. Negative balance o f S was recorded under the treatments receiving no single superphospha te, farmyard manum or crop residues. Application of farmyard manure @ 10 tonnes/ha to both rice and potato in conjunction with 75% (N, P and K @ 45. 10 and 19 kg/ha in rice; 75, 33 and 62 kg/ha in potato) of th e recommended fertilizer was more remunerative than that of 100%.