Forms of Potassium in Punjab Soils

The surface soil samples obtained from different soil zones of the Punjab on an average contained 1925 mg K₂O per 100 g. Nearly 30 per cent of the total potassium was present in the HCl soluble form, 6.1 per cent in fixed form, 0.98 per cent in water soluble and exchangeable form and 0.93 per cent in available form (Neubauer's technique). There are highly significant postive correlations between different forms of potassium. The low availability of potassium to rye seedlings shows that only water soluble and exchangeable potassium was readily available and the release from the fixed form was too small.