Role of Sulfur in Agriculture "Phosphate- Sulfur- Bentonite Mixture for Optimum Utilization of Rock Phosphate as A Fertilizer"

Document Type : Original Article

Abstract


THROUGHOUT several research and development projects, ……. carried.out by the Egypt Sulfur project at the NRC, have proved a prominent role of S in increasing P mobility to root zone; P uptake by the plant ; crop productivity in sandy, saline calcareous and alkaline clay soils.
Semi-pilot and pilot field trials on S and P applications to soils were shown to correct several soil problems. Such applications reduce soil pH, decrease salt accumulation, achieve ionic- balance and mobilize P, Fe and Ca. Such favorable effects of sulfur were promoted by mixing S with rock phosphate (RP) and other nutrients-carrying minerals. Results have also confirmed the effect of sulfur in promoting the efficiency of phosphate fertilizers and their uptake by plants.
A special synergetic effect between phosphates (P) and Sulfur (S) in the soil- plant system proved to increase the efficiency of each other.
Inoculation of S-P mixture with S- oxidizing bacteria enhances the oxidation of S and maximizes its favorable effect on soil pH and on P availability
Besides, applying bentonite clay into the mixture has increased water retention in sandy soils and increased exchangeable Ca on the account of free Ca in the soil solution. Such effect on Ca has markedly increased phosphate availability to plants.
A special mixture of all the above-mentioned materials, RP, S, Bentonite clay and oxidizing bacteria, are now produced under the name of Agrite Phosphate.
*Agrite Phosphate is a bio-mineral sulfur-phosphate fertilizer that proved to be a superior long-acting P fertilizer, as compared to many other phosphates.

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