@article{fdi:010049198,
  title = {{W}hy {R}ice yellow mottle virus, a rapidly evolving {RNA} plant virus, is not efficient at breaking rymv1-2 resistance},
  author = {{P}oulicard, {N}ils and {P}inel {G}alzi, {A}gn{\`e}s and {H}{\'e}brard, {E}ug{\'e}nie and {F}argette, {D}enis},
  editor = {},
  language = {{ENG}},
  abstract = {{P}>{R}ice yellow mottle virus ({RYMV}) reaches a high virus content in rice, is genetically highly variable and evolves rapidly. {N}evertheless, only a small proportion of isolates overcome rymv1-2 rice resistance by mutations in the {VP}g (viral protein genome-linked). {T}he accumulation rates of wild-type ({WT}) and resistance-breaking ({RB}) genotypes of the {E}- and {T}-pathotypes of {RYMV}, with average and low virulence, respectively, were assessed. {B}y quantitative reverse transcriptase-polymerase chain reaction, it was shown that: (i) in resistant plants, both {WT} genotypes reached a level of 105-107 viral copies per milligram of fresh leaf; (ii) the accumulation of {RB} genotypes was variable, but was always much higher than the {WT}, with an {RB}/{WT} accumulation ratio of up to 106; (iii) in susceptible plants, the {RB} genotypes were counter-selected to a similar level. {I}n competition experiments, there was a straightforward exclusion of {WT} by {RB} genotypes in resistant hosts. {T}he mutation rate in {VP}g was more than 1 x 10-3 mutations per site per year. {O}verall, a steady supply of highly adaptive {RB} genotypes was expected in resistant plants. {H}owever, the use of the few possible mutational pathways to virulence is tightly regulated by pathotype-specific genetic constraints: codon usage, mutational bias and sign epistasis. {I}n addition, genetic drift may restrict the fixation of {RB} mutants. {A}ltogether, both genetic and demographic constraints contribute to the low ability of {RYMV} to break rymv1-2 resistance.},
  keywords = {},
  booktitle = {},
  journal = {{M}olecular {P}lant {P}athology},
  volume = {11},
  numero = {1},
  pages = {145--154},
  ISSN = {1464-6722},
  year = {2010},
  DOI = {10.1111/j.1364-3703.2009.00582.{X}},
  URL = {https://www.documentation.ird.fr/hor/fdi:010049198},
}