Extending the durability of cultivar resistance by limiting epidemic growth rates. Issue 1863 (27th September 2017)

• Record Type: Journal Article
• Authors: Carolan, Kevin; Helps, Joe; van den Berg, Femke; Bain, Ruairidh; Paveley, Neil; van den Bosch, Frank
• Is Part Of: Proceedings. Volume 284:Issue 1863(2017)
• Publication Date: 2017-09-27
• Subjects: evolution -- selection -- virulence -- fungicide -- virulence management -- integrated disease control; Biology -- Periodicals; 570.5
• DOI: 10.1098/rspb.2017.0828
• Languages: English
• ISSNs: 0962-8452

Abstract

Abstract : Cultivar resistance is an essential part of disease control programmes in many agricultural systems. The use of resistant cultivars applies a selection pressure on pathogen populations for the evolution of virulence, resulting in loss of disease control. Various techniques for the deployment of host resistance genes have been proposed to reduce the selection for virulence, but these are often difficult to apply in practice. We present a general technique to maintain the effectiveness of cultivar resistance. Derived from classical population genetics theory; any factor that reduces the population growth rates of both the virulent and avirulent strains will reduce selection. We model the specific example of fungicide application to reduce the growth rates of virulent and avirulent strains of a pathogen, demonstrating that appropriate use of fungicides reduces selection for virulence, prolonging cultivar resistance. This specific example of chemical control illustrates a general principle for the development of techniques to manage the evolution of virulence by slowing epidemic growth rates.