Non-Peer ReviewedIn this study, a bioassay for determination of flucarbazone residues in soils has been investigated. The response of five crops grown on soils (0-10cm) from three landscape positions was examined in the Brown soil zone. Lentil, field pea, tame oats, chickpea and oriental mustard were grown for five days in soils spiked with 1,3,5,10 and 20 ppb of flucarbazone. Root and shoot length and shoot dry weight were measured and percent growth inhibition was calculated. Root length inhibition provided the most sensitive and consistent indication of herbicide presence in the soil. Of the investigated crops, oriental mustard was the most sensitive in revealing root inhibition from of flucarbazone in the soil with detectable inhibition down to 1 ppb. The mustard also showed the highest degree of inhibition, up to approximately 70% as
compared to approximately 50% for the other crops. Percent root growth inhibition was soil dependent; the highest degree of inhibition was observed in the upper slope soil and the lowest in the lower slope soil, indicating that soil properties affect the phytotoxicity of the herbicide in the soil