title: The potential of plant viruses to promote genotypic diversity via genotype x environment interactions.
abstract: OBJECTIVE
  Genotype by environment (G × E) interactions are important for the long-term persistence of plant species in heterogeneous environments. It has often been suggested that disease is a key factor for the maintenance of genotypic diversity in plant populations. However, empirical evidence for this contention is scarce. Here virus infection is proposed as a possible candidate for maintaining genotypic diversity in their host plants.
  
  
  METHODS
  The effects of White clover mosaic virus (WClMV) on the performance and development of different Trifolium repens genotypes were analysed and the G × E interactions were examined with respect to genotype-specific plant responses to WClMV infection. Thus, the environment is defined as the presence or absence of the virus.
  
  
  RESULTS
  WClMV had a negative effect on plant performance as shown by a decrease in biomass and number of ramets. These effects of virus infection differ greatly among host genotypes, representing a strong G × E interaction. Moreover, the relative fitness and associated ranking of genotypes changed significantly between control and virus treatments. This shift in relative fitness among genotypes suggests the potential for WClMV to provoke differential selection on T. repens genotypes, which may lead to negative frequency-dependent selection in host populations.
  
  
  CONCLUSIONS
  The apparent G × E interaction and evident repercussions for relative fitness reported in this study stress the importance of viruses for ecological and evolutionary processes and suggest an important role for viruses in shaping population dynamics and micro-evolutionary processes.
authors.affiliation: Experimental Plant Ecology, Radboud University Nijmegen, Heyendaalseweg 135, Nijmegen, The Netherlands. tvanmolken.science@gmail.com
authors.forename: Tamara
authors.initials: T
authors.lastname: van Mölken
authors.forename: Josef F
authors.initials: JF
authors.lastname: Stuefer
mesh_terms: D000704:Analysis of Variance; D005075:Biological Evolution; D018533:Biomass; D004777:Environment; D056084:Genetic Fitness; D014644:Genetic Variation / Q000235:genetics*; D005838:Genotype; D009426:Netherlands; D010935:Plant Diseases / Q000821:virology; D017863:Potexvirus / Q000472:pathogenicity / Q000502:physiology*; D012641:Selection, Genetic; D029921:Trifolium / Q000235:genetics* / Q000254:growth & development / Q000821:virology*