Copper and Zinc Status of Maharashtra Soils

Twenty four surface soil samples, belonging to red, laterite, black, saline, alkali and coastal alluvium types were analysed for copper and zinc contents by chemical and microbiological methods. Water dissolved out negligible quantities of these elements. Cation exchange reagents, ammonium acetate and potassium chloride, extracted slightly larger, but still very small quantities. Acidified ammonium acetate dissolved much larger amounts of zinc. In calcareous and alkali soils, O. IN HCl was not found to be a suitable extract ant. Chelate forming agents, EDTA and pyrophosphate, extracted substantial quantities of the elements and agreed closely with bioassay. It is indicated that Some of the black soils are likely to be deficient in zinc. The results have been discussed on the basis of postulated pools of micronutrients in the soil.