Allelopathic effects of Cocklebur (Xanthium strumarium L.) on germination and seedling growth of some crops

In lab bioassays, the effect of cocklebur (Xanthium strumarium L.) leaves and stem aqueous extracts was studied on germination and seedlings growth of corn, canola, sesame, lentils and chickpea.. In pot culture, the effect of aqueous shoot extracts of Cocklebur was studied on growth of test crops. The leaves and stems extracts significantly reduced the germination, root and shoot lengths of all test crops. The inhibitory effect was concentration dependent. The inhibitory effects were greater on canola germination than on other crops. The aqueous shoot extracts of cocklbure significantly reduced dry weight (DW) of test crops. These results suggest the presence of allelopathic components in cocklebur leaves and stems.