MOBILITY OF METAMITRON IN SOILS UNDER CONVENTIONAL AND REDUCED TILLAGE

The mobility of the triazinone herbicide metamitron (4-amino-3-methyl- 6-phenyl-1,2,4-triazin-5(4H)) under reduced tillage (RT) and conventio nal tillage (CT) in undisturbed soil columns has been studied after se veral water doses application. The amount of metamitron recovery in br eakthrough curve profile and cumulative leaching (BTC's) was 9 and 5% in CT and RT, respectively and the metamitron residues was higher in C T than RT, indicating a low mobility of metamitron under RT vs. CT mai nly due to enhanced biodegradation processes in the first case and to preferential flow in the second one.