Susceptibility genes 101: how to be a good host

Annu Rev Phytopathol. 2014;52:551-81. doi: 10.1146/annurev-phyto-102313-045854. Epub 2014 Jun 23.


To confer resistance against pathogens and pests in plants, typically dominant resistance genes are deployed. However, because resistance is based on recognition of a single pathogen-derived molecular pattern, these narrow-spectrum genes are usually readily overcome. Disease arises from a compatible interaction between plant and pathogen. Hence, altering a plant gene that critically facilitates compatibility could provide a more broad-spectrum and durable type of resistance. Here, such susceptibility (S) genes are reviewed with a focus on the mechanisms underlying loss of compatibility. We distinguish three groups of S genes acting during different stages of infection: early pathogen establishment, modulation of host defenses, and pathogen sustenance. The many examples reviewed here show that S genes have the potential to be used in resistance breeding. However, because S genes have a function other than being a compatibility factor for the pathogen, the side effects caused by their mutation demands a one-by-one assessment of their usefulness for application.

Keywords: biotrophy; compatibility; disease resistance; effector; plant breeding; plant pathogens.

Publication types

  • Review

MeSH terms

  • Genetic Predisposition to Disease*
  • Host-Pathogen Interactions*
  • Microbiota / genetics*
  • Plants / genetics*
  • Plants / microbiology