Coevolution in natural pathosystems: effects of dominance on host-pathogen interactions.
Coevolution in natural pathosystems: effects of dominance on host-pathogen interactions.
复制标题
自然病理系统的共同进化：优势对宿主-病原体相互作用的影响。
作者：
T. Ye;Rong‐Cai Yang;F. Yeh
摘要我们建立了一个新的二倍体寄主和单倍体病原体之间基因互作的互补模型，该模型允许寄主中任意水平的显性。该模型使我们能够评估的影响，超显性，不完全显性，和欠显性的抗性和毒力基因的平衡频率和平衡的稳定性。我们的模型减少到一个基因对基因的模型时，完全显性的抗性假设。计算机模拟表明，我们的模型有两个新的特点。首先，当抗性存在超显性或欠显性时，即使不存在不必要的毒力成本，或者在不必要的毒力成本和抗性有效性之间存在必要的毒力成本，内部平衡点也存在。第二，稳定的抗性和毒力多态性的发生强烈依赖于显性水平。这两个特征表明，在使用基因对基因模型时需要谨慎，特别是在存在超显性或欠显性的情况下。我们的模型特别适合于研究自然病理系统中杂交种群与其病原体之间的协同进化动力学。
ABSTRACT We have developed a new complementary model of gene interaction between diploid host and haploid pathogen by allowing for arbitrary levels of dominance in the host. This model enables us to assess the effects of overdominance, incomplete dominance, and underdominance on the equilibrium frequencies of resistance and virulence genes and on the stability of equilibria. Our model reduces to a gene-for-gene model when complete dominance of resistance is assumed. Computer simulations show that our model has two new features. First, when there is overdominance or underdominance of resistance, the internal equilibrium points exist even when there is no cost of unnecessary virulence or when there is a cost of necessary virulence at the balance between cost of unnecessary virulence and effectiveness of resistance. Second, the occurrence of stable resistance and virulence polymorphism is strongly dependent on the level of dominance. These two features suggest the need for caution when using the gene-for-gene model, especially in the presence of overdominance or underdominance. Our model is particularly suitable for studying the coevolutionary dynamics between hybrid populations and their pathogens in natural pathosystems.