Bioassays for Detection of Butachlor and Oxad1Azon Residues in Soil

Ragi and mustard detected butachlor residues in soil upto 0.01 ppm as measured by GR 50 in root length within a period of seven days. For oxadiazon, ragi and wheat were found to be suitable bioassays, detecting residues upto 0.1 and 5.7 ppm as measured by the per cent germination and GR 50 in root length respectively. Pea, cucumber, green gram, black gram and tomato were fairly rolerant to butachlor and all crops except wheat and ragi to oxadiazon.