Abstract

Persian galbanum seeds have hard dormancy, and washing has a good effect on seed dormancy breaking; it seems that Galbanum seeds are a source of inhibitor material. In this study, we evaluated the allelopathic effects of seed, stem and root aqueous extract of Galbanum in three concentrations (10, 5 and 2.5%) on seed germination and seedling growth of three weeds (common amaranth, purslane and wild barley) with pre and post-emergence method. In pre-emergence experiment, bioassays showed that all organ extracts in most of the concentrations significantly decreased germination percent, germination rate, radicle length and hypocotyl length. In post-emergence method, root (except wild barley) and stem length, dry and wet weight decreased in most of the treatment, viability reduced in some treatment of receiver plant. Also, total protein root content of wild barley plantlet enhanced by exposing them to stem extract (after 48 h), but polyphenol and peroxidase enzyme activity decreased. This study exhibited that galbanum has inhibitor material that decreased seed germination and seedling growth of receiver weeds. So, galbanum is an allelopathic plant that can be considered as a source of allelochemical. Also, galbanum organs can be used as an organic herbicide. Further, one of the main reasons for the hard dormancy of galbanum is the presence of the inhibitor compound.

Key words: Allelopathy, plant aqueous extract, organic herbicide, protein content, enzymes activity.