Zinc requirement of wheat and its influence on zinc fractions in anInceptisol of Agra, Uttar Pradesh

Field experiment was conducted on Agricultural Research Farm, Agra (U. P.) on a zinc deficient Inceptisol soil to assess the effect of different rates, frequency and distribution of Zn in different fractions. Crop of wheat responded to applied Zn up to 22.5 kg/ha application of Zn at highest dose i. e. 30 kg ZnSO4/ha had effects up to wheat crop. For applied Zn on yield of wheat, a field experiment was undertaken to evaluate the effect of graded levels of zinc sulphate (0, 7.5, 15.0, 22.5 and 30.0 kg/ha) on the yield, content and uptake of nutrients in wheat. Different fractions of soil Zn were in dynamic equilibrium with each other. Depletion of water soluble, exchangeable and complexed forms of Zn occurred with a build-up organic, occluded and residual fractions of Zn. Depleted levels of readily available Zn in soil could be replenished by the other pools of soil Zn.