Sulphate salts of different micro-nutrients are the common sources of micro-nutrients. Correction of zinc and copper deficiencies may be made by inorganic fertilizers, e.g. zinc sulphate and copper sulphate or chelates. Application of farmyard manure at 10 tons/ha is able to meet zinc requirements of potato crop. Iron sprays best accomplish correction of deficiencies of iron in the field. Foliar sprays with acidified solution of 0.3% ferrous sulphate or with 0.1% iron citrate has been found to reduce iron chlorosis and significantly increase potato tuber yield of cv. Kufri Jawahar. Fe-EDDHA can also be used successfully in the field.