THE EFFECT OF Phyllanthus virgatus EXTRACT ON COMMON WEED SPECIES

The potential of allelochemicals from Pyllanthus virgatus to inhibit plant germination and growth was tested using 10 common weed species. An aqueous extract of P. virgatus (leaf/stem/fruit), was mixed with agar to produce a 5% FW/v substrate concentration. Seeds of Apium leptophyllum, Avena fatua, Bidens pilosa, Chenopodium album, Echinochloa crus-galli, Lolium rigidium, Parthenium hysterophorus, Raphanus raphanistrum, Sonchus oleraceous and Urochloa pannicoides were placed on the agar and germinated under controlled conditions for 7-16 days. The extract caused a significant reduction in the germination of A. leptophyllum, L. rigidium, P. hysterophorus and S. Oleraceous from 100% down to 63.2%, 88.0%, 49.4% and 40.8%, respectively. Shoot growth was significantly reduced by 8.1% to 65.8% in most weed species. Root growth was so severely affected in all species that the survival of seedlings would be unlikely if the extract environment was maintained.