Groundnut Pod Yield and Leaf Spot Disease as Affected by Potassium and Sulphur Nutrition

The effect of applied K and S, both individually and in combination, on pod yield and Tikka leaf spot (Cercospora archidicola Hori.) of groundnut (Arachis hypogaea L. cv. GAUG-1) was studied in a 4x4 factorial CRD in greenhouse. Dry matter and pod yield were very poor and were not influenced by S application when K was deficient (0.5 meqL⁻¹). K application up to 3 meqL⁻¹ increased both dry matter and pod yield significantly. Application of 3 meqL⁻¹ K and 4 meqL⁻¹ S in the medium produced the highest pod yield (14.01 g/plant) and interaction effect of K and S was significantly positive and synergistic. Natural infestation of Tikka leaf spot disease was observed at flowering and was more prominent on K deficient plants irrespective of S treatment. Mean disease incidence of 55.5% was observed in 0.5 meqL⁻¹ K which decreased to 10.9% in the 3.0 meqL⁻¹ K. There was a substantial loss in yield due to this disease. K application helped in mitigating the adverse effect caused by this disease to a greater extent.