VIEW ARTICLE

Disease Control and Pest Management

Disease Control Through Use of Multilines: A Theoretical Contribution. Richard A. Fleming, Graduate student, Department of Zoology, University of British Columbia, Vancouver, Canada, V6T 1W5; Clayton O. Person, professor, Department of Botany, University of British Columbia, Vancouver, Canada, V6T 1W5. Phytopathology 68:1230-1233. Accepted for publication 30 January 1978. Copyright © 1978 The American Phytopathological Society, 3340 Pilot Knob Road, St. Paul, MN 55121. All rights reserved.. DOI: 10.1094/Phyto-68-1230.

A mathematical model of a multiline is used to illustrate the relationships between the composition of the host crop, the readiness of the plant breeder to change crop composition, the yield losses, and the composition of the pathogen population. Under the assumptions of the model it is shown that an infrequently adjusted multiline is incapable of preventing one genotype from dominating the pathogen population. It is also shown that the relative merits of multiline and monoculture strategies of employing resistance genes depend on the circumstances. Important considerations are stabilizing selection and the readiness of the plant breeder to change crop composition. Practical aspects of multiline implementation are discussed.