Co-Authors:
Horowitz, M., Division of Weed Research, Volcani Institute of Agricultural Research, Newe Ya'ar Experiment Station, Haifa, Israel
HULIN, N., Division of Weed Research, Volcani Institute of Agricultural Research, Newe Ya'ar Experiment Station, Haifa, Israel
Abstract:
Summary. A rapid bioassay for diphenamid is described, based on differential elongation of oat roots after 48 h incubation, which can be used to assess the potency of diphenamid in solution or in soil. In sorption experiments using a slurry technique with soil: water ratios of 1: 2, 1: 3 and 1: 4, the bioactivity of the supernatant was similar for adsorption and release processes. The influence of soil characteristics on the bioactivity of diphenamid was determined by oat response in soil with herbicide and by oat bioassay on the supernatant after equilibration with soil. The results of direct and indirect assays corroborated each other and indicated that the organic matter content of the soil was the main factor affecting bioactivity. Copyright © 1971, Wiley Blackwell. All rights reserved