Overview of approaches in assessing / mapping micro-nutrients with a case of Ghataprabha command area

Abstract

The importance of micronutrients and benefits in crop production are being increasingly recognized in modern agriculture. The incidence of micronutrient deficiencies has become more pounced consequent to the adoption of new strategy in agriculture. Although micronutrients are required in small quantity, they are considering to play a vital role in the plant growth and development and therefore to receive a greater attention in modern agriculture. The current paper throws light on various approaches in assessing / mapping micro-nutrients with a case of Ghataprabha command area was discussed. Studies on status of micronutrient cat ions (Fe, Mn, Cu and Zn) in soils of Ghataprabha command area of Belgam district revealed that the soils in different taluks namely Gokak, Raibag, Chikkodi, Athani and Hukkeri, these soils are alkaline in soil reaction and normal in electrical conductivity . The range and mean value of DTPA extractable iron, manganese, copper and zinc in soils of Ghataprabha command area vary from 0.32 to 11.02, 0.37 to 27.73, 0.54 to 8.28 and 0.03 to 3.88 ppm with a mean value of 3.77, 8.00, 2.54 and 0.51 ppm respectively. As per the limits of 4.5 ppm as deficient, marginal and sufficient in available iron, 21.1, 52.0 and 26.9 per cent of samples fall under deficient, marginal and sufficient category respectively. In respect of available manganese majority of the soil samples (97.1%) fall under category of sufficient (>2.0 ppm) and remaining (2.9%) samples fall under deficient category respectively. As per the deficiency (0.2 ppm) category for available copper, all the command area samples fall under sufficient category respectively. In respect of available manganese, majority of the soil samples (97.1%) fall under category of sufficient (>2.0 ppm) and remaining (2.9%) samples fall under deficient category. As per deficiency ( 2.0 ppm) category for available copper, all the soils of command area fall under sufficient category. In case of zinc 76.9, 9.1 and 14.0 per cent of samples fall under deficiency ( 1.0 ppm) category respectively.