Allelopathic potential of Jimsonweed (Datura stramonium L.) on the early growth of maize (Zea mays L.) and sunflower (Helianthus annuus L.)

Laboratory and glasshouse experiments were carried out to investigate the allelopathic potential of different plant parts of D. stramonium on maize and sunflower on early growth stages. The aqueous leachates of D. stramonium roots and shoot did not produc a significant effect on germination and shoot length of maize, but root length of maize was significantly reduced at the highest (1/1) D. stramonium roots leachate compared to control. From the other side, germination of sunflower was significantly reduced at the highest (1/1) D. stramonium shoot leachate concentration, but lower (1/5 and 1/2) D. stramonium roots leachate concentrations significantly increased root and shoot length of sunflower compared to control. In glasshouse experiment, no one treatment with different D. stramonium plant residues significantly affected density, height and fresh weight of maize plants compared to control. Contrary, D. stramonium mixtures with 1/1 root and shoot residues significantly reduced plants density and fresh weight of sunflower plants compared to control. Lower (1/2 and 1/5) mixtures of D. stramonium roots residues and mixture with 1/5 D. stramonium shoot residues significantly increased the height of the sunflower plants