Terai Zone of West Bengal is considered as a fragile ecological region because of high rainfall and prolongs winter. Plants cannot derive nutrients effectively from its organic source because of slow mineralization. Soils are acidic and light textured. High rainfall coupled with low pH lead to deficiency of several macro and micro-nutrients and at the same time toxicity of some other elements. | Atmospheric nitrogen fixing capacity of Azotobacter isolate from cooch behar and Jalpaiguri districts soil of West Bengal India