Abstract：The concept of allelopathy, the universality of its exisence and its roles in ecology, agriculture, forestry and horticulture are outlined. The chemical nature and mechanisms of action of allelochemicals are generaly discussed. In addition, this overview has given a full valuation for the significance and prospective of allelochemical research and suggested some ways in which present and future research would be useful. We expect that this overview will provied comprehensive information both for researchers in the disciplines and for those who intester in as well as desire to learn something about the subiject.
