H.T.ChannalD.N.Samaraweera2016-07-232016-07-232009http://krishikosh.egranth.ac.in/handle/1/69507Soil characterization, incubation study and field experiments were conducted to study the distribution of S forms, transformation and direct and residual effect of sulphur on growth, yield and quality of rice-rice cropping system during rabi/summer and kharif seasons during 2007, respectively. In characterization study, there was lot of variations among sulphur forms in soils of eight selected locations. Correlation studies revealed that sulphate sulphur was significantly and positively correlated with EC and CEC, water soluble sulphur, organic sulphur and total sulphur. Water soluble sulphur significantly correlated with pH, EC, organic sulphur, non-sulphate sulphur and total sulphur. Results obtained from incubation study revealed that Factomphos increased sulphate sulphur and water soluble sulphur up to 32nd day of incubation and these fractions declined thereafter. Field investigations on response of rice to applied two sulphur sources indicated that Facomphos was superior over gypsum and the highest grain and straw yield (57.09 and 63.63 q ha-1), protein and methionine content (6.17% and 2.51 mg g-1) were recorded with Factomphos apllied @ 50 kg ha-1, respectively. In succeeding rice, same treatment registered highest grain and straw yield (51.90 and 58.02 q ha-1), protein and methionine content (5.92% and 2.18 mg g-1), respectively. Economic analysis revealed that application of Factomphos @ 50 kg ha-1 resulted the highest benefit:cost (B:C) ratio of 1.69 in first rice with net return of Rs. 16,847/ha which was 33.2 per cent increase over control (Rs. 12647/ha). Similarly, the highest benefit:cost (B:C) ratio of 1.64 in succeeding rice with net return of Rs. 14,565.00/ha was recorded with the residual effect of the same treatment and that was 55.9 per cent increase over control (Rs. 9343/ha).Thesis