*Department of Science & Agricultural Chemistry, University of Agricultural Sciences, GKVK, Banglore-560065
**ICAR Scheme on Water Management, Agricultural Research Station, Navalgund, Dharwad District.
University of Agricultural Sciences, Bangalore, 560 065, India
Online published on 15 December, 2011.
Studies on leaching rate and distribution of carbaryl and phorate in soil columns revealed that the leaching of both the pesticides was more in coarse-textured red and laterite soils than that in fine-textured black and saline-alkali soils. In saline-alkali soils no loss of the pesticides occurred during first 18 hours. The leaching rate of carbaryl and phorate in different soils followed the order: red soil > laterite soil > black soil > saline-alkali soil. Very low leaching rate of these pesticides in saline-alkali soil was probably due to the low hydraulic conductivity (0.25 cm/h) of the soil and/or due to their sorption on soil. Maximum amount of carbaryl and phorate were retained in the upper (0–7 cm) layer of soil columns particularly in black and saline-alkali soils, while appreciable downward movement occurred (upto 18 cm) in red and laterite soil.
