Herbicidal effects of aqueous extracts of three Chenopodium species on Avena fatua
Herbicidal effects of aqueous leaf extracts of three Chenopodium species; Chenopodium album L., Chenopodium murale L. and Chenopodium ambrosioides were evaluated on wild oat (Avena fatua L.), one of the problematic weeds of wheat. Among the aqueous extracts of 0, 2, 4 and 6% (w/v) employed in bioassays, 6% of C. album and 2% of C. murale caused significant inhibition in germination of A. fatua resulting in 66 and 34% decline in germination, respectively. Lower concentration of 2% of all the three Chenopodium species enhanced seedling growth of A. fatua. The highest extract concentration of C. album (6%) markedly suppressed both length and biomass of shoot of test weed species. The highest herbicidal effect was exhibited by 6% C. album leaf extract, resulting in 88, 89, 70 and 92% reduction in maximum and total root length, number of roots and root biomass, respectively. This study concludes that the aqueous leaf extracts of C. album contain herbicidal constituents for the management of A. fatua.
Key words: Aqueous extracts, Avena fatua, Chenopodium, natural herbicides.