Abstract
In this work Bioassay technique had used to identify the allelopathic potential effects of different parts of Johnson grass on the germination and seedlings growth of bread and durum Wheat, 2-row and 6-row Barley, Chickpea and Lentil. The results showed different inhibition of allelopathic potential for the residues in comparing with the control treatments for all six crops. The root extracts had the highest inhibition impacts on all of the characteristics studied, and less effect of both shoots and seeds. While the effect of seed extracts had the same effect or as control in most cases. The radical length and dry weight affected more than germination percentage, shoot length and shoot dry weight. The results also indicated that Lentil was more affected than 2-row Barley, bread Wheat, 6-row Barely and durum wheat, while the Chickpea had the lowest response.
