Biologically Active Substances in Subterranean Parts of Purple Nutsedge

Abstract
The growth of barley (Hordeum distichum L., var. Esperanza) seedlings in nutrient solution was reduced by purple nutsedge (Cyperus rotundus L.) plants growing in connected vials and by addition of ethanolic extract of purple nutsedge. Aqueous and ethanolic extracts from subterranean parts of purple nutsedge reduced the germination and root elongation of barley; stimulations of barley root elongation were obtained with diluted aqueous extract. The germination of barley, mustard (Brassica nigra L., var. Alsace), and cotton (Gossypium hirsutum L., var. Acala 1517) was reduced in soil which had been infested previously with purple nutsedge. Radicle elongation of barley was inhibited by ethanolic extract of soil previously infested. Chromatographic studies indicated that the inhibitors are phenolic substances.