Agricultural College and Research Institute, Coimbatore, Madras
The relationship between total and one per cent citric acid soluble forms of phosphorus and potash was assessed in the soils of Tanjore (new and old delta), Nilgiris, Kolli, Yercaud and Anamalai hills. The soils belong to three categories—alluvial, lateritic and laterite. A significant correlation was obtained between total and citric soluble forms of phosphorus in the soils of Nilgris—in the region between 1500 and 1800 metres as well as in the region above 1800 metres, Yercaud, Kolli hills and Anamalais. Similarly a significant correlation was obtained in the case of total and citric soluble potassium in the soils of Tanjore (new and old deltas) and the Nilgiris in the region between 1500 and 1800 metres.
