Research Journal of Agricultural Sciences
Vol : 3 - Issue : 6 ; 1170-1174
S Selvaraj, B Basavaraj and N S Hebsur
Department of Soil Science and Agricultural Chemistry,
College of Agriculture, University of Agricultural Sciences, Dharwad - 580 005, Karnataka, India
Sixty surface (0-20 cm) soil samples each from the farmers paddy field collected from different villages in Gangavati taluk, North Karnataka in the year 2010. Distributions of different forms of zinc in twelve village paddy growing soils were studied. The results showed that more than 79.38% in Herura village and 99.35% in Maralanahalli village of total zinc occurred as residual zinc, whereas water soluble + exchangeable Zn occurred only in 0.11% in Maralanahalli village and 6.71% in Sanapura village soil samples. Soils contained water soluble + exchangeable zinc from 0.13 to 1.93 ppm, organically bound zinc from 0.16 to 5.32 ppm, manganese oxide bound zinc from 1.00 to 5.89 ppm, amorphous sesquioxides bound zinc from 0.09 to 2.16 ppm, crystalline sesquioxides bound zinc 1.21 to 9.94 ppm and residual zinc from 53.29 to 277.99 ppm. In this fractions water soluble + exchangeable zinc was low in all the soils when compared to other fractions, still it is very important from the plant availability point of view. Amorphous sesquioxidebound form of zinc is the seat for zinc adsorption because of its high specific surface area. Crystalline sesquioxide bound form of zinc dominated when compared to water soluble + exchangeable, organically bound, manganese oxide bound and amorphous sesquioxide bound zinc fractions.
| Published online : 12-Jan-2017