Mobilization of Iron in Soil and Its Influence on Phosphate Availability Through the Chelating Effects of Aqueous Extracts of Some Green Manuring Plant Materials

Department of Soil Science and Agricultural Chemistry, Faculty of Agriculture, University of Kalyani, West Bengal Manuscript received 16 April 1974; accepted 2 May 1975 Mobilization of iron in soil through the chelation effects of the aqueous extracts of Alfalfa, Berseem and P. calcaratus plant materials, and its effect on the release of phosphate has been studied with two types of West Bengal soil at different levels of pH and different submergence periods. The maximal release of iron was observed in all cases on incubation of the soil samples for 15 days. Irrespective of soils the order of chelating ability was observed to be Alfalfa > P. calcaratus > Berseem. No definite correlation could, however, be obtained between the release of iron and phosphate availability