Vol. 11, Issue 11 (2022)

The effect of different potassic salt viz., potassium chloride, potassium sulphate, potassium nitrate and dipotassium hydrogen phosphate at 1.0,0.5, 0.05 and 0.01 per cent concentrations of potassium on the growth and sclerotial formation of R. solani was studied. It was observed that the mycelial growth was enhanced by the salts at the lower concentrations of potassium and inhibited at higher concentrations of potassium. The inhibition was maximum in the case of potassium chloride followed by potassium sulphate, potassium nitrate and dipotassium hydrogen phosphate. Potassium chloride exerted good inhibition of the mycelial growth of the pathogen at all the concentrations. Maximum percentage of inhibition was recorded as 64.63 per cent in the case of KCl at one percent concentration. Sclerotial formation was very poor with potassium chloride and potassium sulphate. Maximum inhibition of sclerotial production was observed at 0.5 per cent and 1.0 per cent production was observed at 0.5 per cent and 1.0 per cent concentration of KCl₂ and potassium sulphate respectively.