Phospher Fertilizer -Single Super Phosphate
Importance of the Fertilizer Single Super Phosphate (SSP) is the first fertilizer produced commercially. It is a water soluble phosphatic fertilizer since the phosphate present as Monocalcium Phosphate. It has lowest price per kilogram preferred by small and marginal farmers. Its production process is simple. For production Rock phosphate is mixed with sulphuric acid to form slurry and solidification done by process called Denning. It supplies Calcium and Sulphur also.
Amount of Available Nutrients SSP contains 18 % Phosphorous. It also provides 12% sulphur, 21 % calcium.
Compatibility in fertilizer mixtures SSP can be mixed with Murate of Potash, Potassium Sulphate, Ammonium Sulphate, and Ammonium Phosphate. It should be mixed only prior to application with Calcium Ammonium Nitrate, Sodium Nitrate and Urea. It can’t be mixed with Calcium Carbonate.
Reaction of the Fertilizer in Soil SSP when applied in soil it will form monocalcium phosphate which is water soluble and so plant available form. In acidic soils Monocalcium phosphate react with iron and aluminium ions to produce varieties of phosphate which may include colloidal iron and aluminium phosphate. In alkaline soils Monocalcium Phosphate converted to Dicalcium phosphate and then to Tricalcium Phosphate and finally forms Apatite.
Situations where Recommended It is advisable to apply as basal dose since the phosphorus requirement is high during the early growth period of the crop. Early application promotes early growth which in turn leads better utilization of soil nutrients. The fertilizer is suitable for all crops and can be applied to all soils. In acid soils, it should properly be used in conjunction with organic manure. It should be applied before or at sowing or transplanting. SSP is suitable for short duration crops where quick response is required.
References 1. Yawalkar, K. S., Agarwal, J. P., and Bokde, S., (1996) Manures and Fertilizers, Agri-Horticultural Publishing House, Nagpur