Allelopathic potential of mugwort (Artemisia vulgaris L.) to control the Italian ryegrass (Lolium multiflorum Lam.) in winter wheat

The allelopathic potential of mugwort was evaluated in laboratory, glasshouse and field assays to control the Italian ryegrass (L. multiflorum) in winter wheat (Triticum aestivum L.). Extracts of mugwort inhibited the seed germination and radicle and hypocotyl lengths of Sinapis alba L. and followed the order: leaf extracts > stem extracts > rhizome extracts. The aqueous extract of aerial biomass (leaves + stems) of mugwort at the highest concentration (25% w/v) may be considered as a potent inhibitor of seed germination and plant growth of L. multiflorum. The application of aqueous extract on the soil surface as pre-emergence herbicide was found most effective for maximum efficacy against weeds. However, the bioactivity of mugwort extract in soil decreased with the increase in extract concentration. In field experiments, the mugwort extract (20% w/v) alone gave efficacy of 50% against L. multiflorum; furthermore, the dose of chlorsulfuron was reduced up to 80%, when aqueous extract were added in the spray solution. The mugwort extract alone or in mixture with chlorsulfuron significantly increased the wheat yield in the field. The extract of mugwort used as foliar bioherbicide did not control L. multiflorum.