RT Journal Article
SR Electronic
T1 Maintenance of variation in virulence and reproduction in populations of an agricultural plant pathogen
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2020.04.15.043208
DO 10.1101/2020.04.15.043208
A1 Anik Dutta
A1 Daniel Croll
A1 Bruce A. McDonald
A1 Luke G. Barrett
YR 2020
UL http://biorxiv.org/content/early/2020/04/16/2020.04.15.043208.abstract
AB Genetic diversity within pathogen populations is critically important for predicting pathogen evolution, disease outcomes and prevalence. However, we lack a good understanding of the processes maintaining genetic variation and constraints on pathogen life-history evolution. Here, we analyzed interactions between 12 wheat host genotypes and 145 strains of Zymoseptoria tritici from five global populations to investigate the evolution and maintenance of variation in pathogen virulence and reproduction. We found a strong positive correlation between virulence and reproduction, with substantial variation in both traits maintained within each pathogen population. On average, highly virulent isolates exhibited higher fecundity, which might increase transmission potential in agricultural fields planted to homogeneous hosts at a high density. We further showed that pathogen strains with a narrow host range (i.e. specialists) for fecundity were on average less virulent, and those with a broader host range (i.e. generalists) for virulence were on average less fecund on a given specific host. These trade-offs costs associated with host specialization might constrain the directional evolution of virulence and fecundity. We conclude that selection favoring pathogen strains that are virulent across diverse hosts, coupled with selection that maximizes fecundity on specific hosts, may explain the maintenance of these pathogenicity traits within and among pathogen populations.Competing Interest StatementThe authors have declared no competing interest.