Micronutrients plays an important role in increasing quality of crops. In crop production, application of macronutrients without giving much priority on micronutrients imbalance the soil ecosystem as well as the plant sustenance. Calcareous soils of Bihar found in districts like Champaran, Saran, Kaimur, Kishanganj, Muzaffarpur, Darbhanga, Saharsa and Samastipur. Calcareous soils are characterised by presence of high calcium carbonate (>15 %) with increasing pH (alkaline upto 9.0). Hence, micronutrients (Fe & Zn) are fixed in insoluble form which is not available for plant growth. So, due consideration should be given to apply judicious mixture of both macro and micro nutrients as required by the crop.