Alluri Padma Raju, Acharya N.G. Ranga Agricultural Univ, Rajendranagar, Hyderabad, India and Poonam Mala Kondaiah, Dept of Agriculture, Basheerbagh, Hyderabad, India.
Systematic studies were carried out for better land use planning in Andhra Pradesh (India). As a part of these studies, soil maps are prepared for an area of 26 million hectares in 1:250,000 scale. The genesis and morphology of these soils were studied and they were classified. Utilizing these maps and the information generated from 22 automatic weather stations, land use planning was made for crop production on both arable and non-arable areas in all the 22 agricultural districts of Andhra Pradesh. Impact studies were also initiated. Awareness camps were organized for farmers and extension staff for effective use of soil map. Government of Andhra Pradesh is planning to prepare soil maps 1:25,000 scale for selected areas based on original maps for more clarity for different areas with low rainfall (less than 500 mm/year). Information on soil physical constraints affecting crop growth was generated for the soils of Andhra Pradesh state. The physical constraints included crusting and hardening, shallow soils, soil erosion and runoff, subsoil hard pan, impeded drainage and high permeability. These constraints being highly location specific, suitable management practices were developed to make those soils productive. Location specific technologies developed in this regard are incorporation of paddy husk/powdered groundnut shells/composted coir pith/paddy and sorghum straws and green leaf manure for soils with crusting and hardening; formation of edges for shallow soils; kantoor cultivation, vegetative barriers and check dams for arresting soil erosion and runoff; crowbarring/chiselling up to a depth of 30 to 45 cm for soils with subsoil hard pan; sub-surface drainage for increasing the productivity of water logged soils and addition of tank silt/clay to reduce the permeability. Suitable crops and cropping systems were identified to suit these soils. The areas deficient in secondary and micronutrients were delineated in all the 22 districts of Andhra Pradesh. Sulphur and zinc were found to be highly deficient in majority of the soils of Andhra Pradesh. Soil fertility maps were prepared for all the new trends. Corrective measures were developed for increasing the crop productivity in nutrient deficient soils both by soil application and through foliar spray. Information was also generated on the extent of saline, saline – alkaline and acidic soils of Andhra Pradesh and location and situation specific reclamation measures were standardized. Long term measures were recommended for arresting further soil degradation. Research on bio energy plantations were carried out for better utilization of marginal and degraded lands. Crop specific eco-friendly technologies were generated viz., integrated pest management, integrated nutrient management, bio fertilizers, bio pesticides and measures to reduce global warming. Suitable measures were worked out for minimizing the effects of natural calamities like cyclones, floods and severe droughts. Attempts were also made to minimize the effects of Tsunami on crop plants.