RESEARCH ARTICLE N

Full list of author information is available at the end of the article(HR) in infected and adjacent cells [1]. Defence activa-tion requires pathogen detection, which can occur outside or inside the plant cell, by one of two known distinct recognition mechanisms [2-4]. The first line of detection resides at the cell surface and involves rec-ognition of pathogen-associated molecular patterns mune signalling using “effector molecules ” [4]. Plants in turn possess a second line of defence, which is represented by proteins that detect specific effector molecules or their effects on host cell components. This mechanism is called ‘effector-triggered immunity ’ (ETI). These intracellular im-mune receptors, termed R (resistance) genes, encode pro-teins that resemble mammal NOD-like receptors and typically carry a nucleotide binding and leucine-rich repeat * Correspondence