[Objective] The ability of the allelopathy of the different concentrations of extracts from the soil around the alfalfa roots with 15 year-old and 4 year-old and its effect on following crop growth were researched.[Method] The Medicago sativa L.,Panicum miliaceum L.and Avena nuda L.seeds were cultured on the paper containing the different concentrations of extracts.[Results] There was not efficiency of the extracts from the soil around the Medicago sativa L.roots on seed germination of Panicum miliaceum L.,...