Unlike mammals, plants lack internal specialized immune cells to defend against pathogens. Instead, they rely on the innate immunity of the individual cells and have evolved a sophisticated signal transduction network to respond to pathogens (Jones & Dangl, 2006). For example, protein receptors localized on the plant cell membrane can detect conserved pathogen-associated molecular patterns (PAMPs), leading to an immune response cascade, such as the rapid release of reactive oxygen species (Tsuda & Katagiri, 2010). Plants also secrete defence molecules into apoplasts to combat pathogen invasion (Doehlemann & Hemetsberger, 2013).Pathogens can secrete effectors to overcome the host immunity and establish an infection (Dou & Zhou, 2012;Latijnhouwers