Sequential extraction and chromatographic procedures were used to isolate inhibitors of yellow nutsedge growth from sweet potato periderm tissue. Most of the inhibitory activity was found in a single high pressure liquid chromatography peak that contained 1.2% of the periderm dry weight. Concentration-response data indicated that yellow nutsedge is highly sensitive to this fraction. Several other fractions inhibited yellow nutsedge root growth, but they did not compose a major portion of the inhibitory capacity of the periderm extracts.
