Allelopathic potential of Amaranthus viridis L. against annual ryegrass.

Allelopathic effects of extracts from Amaranthus viridis on annual ryegrass have been observed in petri-dish bioassays. The result showed that germination percentage, plus root and shoot growth were significantly decreased compared to controls especially by extracts from dried samples. Extracts at 50% and 100% from dried samples and 100% from fresh plant samples were more toxic to ryegrass. Ryegrass was mostly inhibited by 100% followed by 50% dried and 50% fresh plant extract. The result also suggests that phytotoxicity of Amaranthus viridis depends on the extract’s preparation procedures.