Resistance to phytopathogens e tutti quanti: placing plant quantitative disease resistance on the map

Fabrice Roux, Derry Voisin, Thomas Badet, Claudine Balagué, Xavier Barlet, Carine Huard-Chauveau, Dominique Roby and Sylvain Raffaele

Résumé:

Plant disease resistance can be seen as a process of a dual nature: both qualitative and quantitative. The nature of non-self molecules perceived by plants has led to the depiction of plant immunity as a two-layer defence system. The first layer is mediated by cell surface and intracellular pattern recognition receptors (PRRs) which perceive conserved microbial elicitors, termed pathogen-associated molecular patterns (PAMPs). The perception of these conserved elicitors initiates cascades of signalling and transcription events, known as PAMP-triggered immunity (PTI). Adapted pathogens secrete effector molecules able to suppress PTI, but which may also be recognized by plant intracellular resistance (R) proteins. This initiates effector-triggered immunity (ETI), the second layer of plant defence. ETI typically yields complete disease resistance phenotypes against pathogens containing the recognized effector, a process designated as qualitative resistance. By contrast, perception of a single PAMP typically has a weaker contribution to overall plant resistance. More generally, in the absence of qualitative resistance, an incomplete resistance phenomenon is often observed, leading to a reduction rather than absence of disease. This is usually referred to as quantitative disease resistance (QDR).

Revue:

Molecular Plant Pathology

Lien:

onlinelibrary.wiley.com/doi/10.1111/mpp.12138/full