Soil persistence of cyanazine under field conditions in humid tropic

Abstract

The persistence of cyanazine {2-[[4-chloro-6(etylamino)-s-triazin-2-yl] amino]-2 metylpropionitrile} applied in pre-emergence at 1.25, 1.75 and 2.25 kg/ha was studied under field conditions during three years. A phytotron bioassay using oat (Avena sativa L.) showed that cyanazine was not present at phytotoxic levels in the top soil samples (0-10 cm depth) taken from treated plots four weeks after treatment in areas cultivated with soybeans.