Studies on Some Aspects of Soil Sulphur and Response of Sunflower to Sulphur Application

Typical acid soils (Inceptiso/s) mostly from coastal areas in Karnataka were characterised for different forms of sulphur present therein. Significant relationships existed between various fractions with total sulphur. The sulphur retention capacities were high in these soils dominated by kaolinitic clay minerals associated with low pH. While the increase in seed yield of sunflower due to graded doses of sulphur application was not significant, the contents of amino acids, cystine and methionine were significantly increased with 10 and 20 ppm S levels. Sulphur application enhanced the concentration of sulphate and heat soluble forms.