Govind Ballabh Pant University of Agriculture and Technology, Pantnagar, Udham Singh Nagar District, Uttar Pradesh, 263145.
1Present address: Central Research Institute for Dryland Agriculture, Santoshnagar, P.O., Saidabad, Hyderabad, Andhra Pradesh, 500059.
A pot culture study was conducted to study phosphorus adsorption and release characteristics of two soils each from tarai (Mollisols) and bhahar (Entisols) regions of Uttar Pradesh. Langmuir constants of P sorption capacity (b) and P affinity (k) ranged from 110.2 to 142.2 mg kgl and 0.43 to 1.31 L mg−1, respectively. The cumulative release of P had high level positive relationship with the supply parameter (r = 0.968***), irrespective of the level of P. Tarai soils with slightly lower pH, clay content and CEC than the Bhabar soils, did not differ appreciably in respect of adsorption, desorption and supply parameter of P, owing to their similar mineralogical make-up.
Phosphorus adsorption, Langmuir isotherm, cumulative release of P, supply parameter, tarai soils, bhabar soils, wheat, maize
