Carolan Kevin, Helps Joe, van den Berg Femke, Bain Ruairidh, Paveley Neil, van den Bosch Frank
Rothamsted Research, Harpenden AL5 5LS, UK
Rothamsted Research, Harpenden AL5 5LS, UK.
Proc Biol Sci. 2017 Sep 27;284(1863). doi: 10.1098/rspb.2017.0828.
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.
品种抗性是许多农业系统中病害防治计划的重要组成部分。使用抗性品种会对病原菌群体施加选择压力，促使其毒力进化，从而导致病害防治效果丧失。人们提出了各种部署寄主抗性基因的技术，以减少对毒力的选择，但这些技术在实际应用中往往困难重重。我们提出了一种维持品种抗性有效性的通用技术。该技术源自经典群体遗传学理论；任何降低毒性菌株和无毒菌株群体增长率的因素都会减少选择。我们以杀菌剂应用的具体例子进行建模，以降低病原菌毒性菌株和无毒菌株的增长率，结果表明，合理使用杀菌剂可减少对毒力的选择，延长品种抗性。这种化学防治的具体例子说明了通过减缓流行增长率来管理毒力进化的技术开发的一般原则。
