Mapping of DTPA Extractable Micronutrients in Sugarcane Soils of Sudhalagunta Sugar Factory, Andhra Pradesh, India – A GIS Approach

Sugarcane is the most important commercial crop grown in India and plays vital role in agricultural and industrial economy. In Andhra Pradesh, more than 50% of sugarcane is produced from Chittoor district for sugar and jaggery production. Sugarcane is heavy nutrient requirement crop and also removes considerable amount of nutrients through biomass. Continuous application of straight fertilizers, limited use of organic manures as well as non recycling of crop residues causes micronutrient deficiencies in soil. Keeping this in view, the present study was taken up to study the physico-chemical properties and DTPA extractable micronutrients and mapping of these nutrients. Soil samples along with geo reference coordinates were collected and analyzed for physico-chemical properties and DTPA extractable micronutrients (Fe, Mn, Zn and Cu). The digital soil maps for DTPA extractable micronutrients were generated with geo reference coordinates by using GIS approach. The analytical data of soils in Sudhalagunta sugar factory zone, Chittoor district showed that 80% of samples were slightly alkaline in reaction followed by 13% of samples were neutral in reaction. Regarding electrical conductivity, 16% of soils were slightly saline in nature. Among micronutrients, except DTPA-Zn, all cationic micronutrients were existed in above critical limit in this factory zone, 11% of soils showed Zn deficiency. Similar trend was noticed in plant Zn content. 18.4% of plant samples showed Zn deficiency. Remaining micronutrients were in sufficient range. Digital maps for DTPA - Fe, Mn, Zn and Cu have prepared.