17 M. S. Islam H. Kato-Noguchi Journal of Animal and Plant Sciences JAPS 20162016/12/01 26 6 1765-1771 1018-7081 NA <p>The present study was conducted to evaluate the allelopathic potentiality of&nbsp;<em>Cyperus</em><em>&nbsp;difformis</em>from the Cyperaceae family. Aqueous methanol extracts from&nbsp;<em>C. difformis</em>&nbsp;were applied at four concentrations (0.01, 0.03, 0.1 and 0.3 g dry weight [DW] equivalent extract/mL) on the seedling growth of eight test species namely, cress (<em>Lepidum sativum&nbsp;</em>L.), lettuce (<em>Lactuca sativa&nbsp;</em>L.), alfalfa (<em>Medicago sativa&nbsp;</em>L.), rapeseed (<em>Brassica napus&nbsp;</em>L.), Italian ryegrass, (<em>Lolium multiflorum&nbsp;</em>Lam.), barnyard grass (<em>Echinochloa crus-galli&nbsp;</em>L.), timothy (<em>Phleum pratense&nbsp;</em>L.) and sand fescue (<em>Festuca megalura</em>&nbsp;Nutt.). A complete inhibition of seedlings of lettuce was found at concentration of 0.1 g DW equivalent extract/mL<em>.</em>At a concentration of 0.3 g DW equivalent extract/mL, complete inhibition was also found in cress shoot and root of cress, alfalfa, timothy and sand fescue, whereas others test species showed more than 90% inhibition. This inhibition was concentrations dependent and increased with increasing extracts concentrations. Considering concentrations required for 50% growth inhibition (I<em>50</em>), rapeseed was the most sensitive to the extracts.The results indicate that,&nbsp;<em>C.</em><em>&nbsp;difformis</em>may possess allelopathic properties and therefore, could be a candidate for the isolation and identification of allelopathic substances to develop environment friendly bio-herbicides.</p> allelopathy and allelochemicals, Cyperus difformis, aqueous methanol, I50, bio-herbicides Pakistan Agricultural Scientists Forum https://thejaps.org.pk/AbstractView.aspx?mid=2016-JAPS-231