Seed to Seed Allelopathic Effects between Wheat and Weeds

ABSTRACT: Wheat and their weeds can interfere together during seed germination and seedling growth. The purpose of this research was to survey the interaction seed to seed between wheat and some of its main weeds like curly dock (Rumex crispus L.), datura (Datura stramonium L.), London rocket (Sisiymbrium irio L.), carrot (Daucus Carota L.), harmel (Peganum harmala L.), horay cress (Cardaria Draba L.), wild barley (Hordeum spontaneum C. Koch.), and oat (Avena ludoviciana Durieu). Seed germination and seedling growth factors (seedling root and shoot length, dry and fresh weight) of datura, carrot, wild barley, and horay cress were reduced by the presence of wheat seeds, while germination and seedling growth of London rocket, harmel, and oat were increased by neighboring wheat seeds. So that, seed germination of London rocket, harmel, and oat from 45.31%, 92.19%, and 96.88% in control treatment (without wheat seeds) increased to 64.06%, 98.44%, and 98.44% in treatments that these weed seeds were beside wheat seeds. Some of weeds like curly dock, carrot, oat, London rocket, harmel, horay cress, wild barley, and datura had inhibitory effects on seed germination and seedling growth of wheat. May be saying the release of inhibitory substances from seeds of weeds and wheat would be the responsible for the observed effects