In the plant immune response, pathogen-associated molecular patterns (PAMPs) are recognized by pathogen recognition receptors, triggering a defense response known as PAMP-triggered immunity (PTI). The pathogen can escape this defense response by deploying effectors. In response, plants utilize a surveillance mechanism mediated by R-genes coding for proteins characterized by a nucleotide-binding site leucine-rich repeats (NB-LRR). Upon recognition of pathogen effectors, a cascade of reactions leads to a hypersensitive response [effector-triggered immunity (ETI)] (Jones and Dangl 2006). This type of response is associated with the production of reactive oxygen molecules and localized cell death, mediating the resistance to biotrophic and hemibiotrophic fungi (Greenberg and Yao 2004; Morel and Dangl 1997). Defenses against biotrophic pathogens are also regulated by a salicylic acid (SA)-dependent pathway, which plays a role in both local defense reactions and induction of systemic acquired resistance (Durner et al. 1997). In contrast, defenses against necrotrophic pathogens are regulated by induction of jasmonic acid (JA) and ethylene signaling (Glazebrook 2005). In the plant defense response, there is an antagonistic cross talk between SA and both ethylene and JA pathways, as well as SA and auxin signaling pathways (Kazan and Manners 2009).