VIEW ARTICLE

Letter to the Editor

Epidemiological Mechanisms of Mycoherbicide Effectiveness. X. B. Yang and D. O. TeBeest. First author: Department of Plant Pathology, Iowa State University, Ames 50011; second author: Department of Plant Pathology, University of Arkansas, Fayetteville 72701. Phytopathology 83:891-893. Accepted for publication 9 July 1993. Copyright 1993 The American Phytopathological Society. doi:10.1094/Phyto-83-891.

The use of mycoherbicides is one of two major approaches for biological control of weeds; the other is the classical approach in which plant pathogens are released to control weeds through natural spread. Since the development of Collego (TUCO Div., Upjohn Co, Kalamazoo, MI), the commercial formulation of Colletotrichum gloeosporioides (Penz.) Sacc. f. sp. aeschynomene (CGA) used to control northern jointvetch (Aeschynomene virginica (L.) B.S.P.) in the southern United States, more than 160 fungal pathogens have been studied as potential mycoherbicides. However, many pathogens have not been successfully developed and used despite extensive research and development. In a recent review, Charudattan (4) found a high rate of failure in this area. This letter examines the question of weed-control efficacy based on epidemiological theory.