ABSORPTION AND DEGRADATION OF METALAXYL IN MUSTARD PLANT (BRASSICA-JUNCEA)

Absorption and degradation of metalaxyl were studied in mustard (Brass ica juncea) plants after application as a seed dresser, a foliar spray , and a combination of both under subtropical conditions in India. Res ults indicated that absorption of metalaxyl increased up to 30 days wh en it was applied as a seed dresser; thereafter, it started declining and was not detectable after 60 days of sowing, The maximum residues ( average, 9.03 ppm) of metalaxyl were found after 1 day of spraying. Th e dissipation of metalaxyl after initial deposits on mustard plants wa s almost complete after 15 days of spraying. The safe waiting period o f metalaxyl was calculated to be 62 and 8 days for seed dresser and fo liar application, respectively, The seeds raised through treatments un der study were completely free from any detectable amount of metalaxyl residues. (C) 1997 Academic Press.