Allelopathi Effect of the Leaf Extracts of Zizyphus spina-christi (Sedr), Salix fragilis L. and Ricinus communis L. on Seed Germination Percentage of Triticumae stivum L. in Iraq

This study investigated the effect of the aqueous leaf extracts of Zizyphuss pina-christi (Sedr.), Salixfragilis L., and Ricinus communis L. on seed germination percentage of (wheat) Triticumae stivum L. Boiled water and alcohol were used to prepare different concentrations of leaf extracts (0%, 20%, 40%, 60%, and 80%) and control. Results showed that the effects of alcoholic leaf extracts of Zizyphuss pina-chris L, Salix fragilis L and Ricinus communis L on seed germination percentage were superior over those of the control (distilled water). Moreover, the alcoholic leaf extract of Zizyphus exerted the highest impact on seed germination percentage. Increased concentration of all leaf extracts inhibited seed germination, except under 20% alcoholic leaf extract of Zizyphus, which showed the opposite effect, which in turn reflected the increase in other growth parameters.