Jasmonic acid (JA) is a natural hormone regulator involved in development,responses against wounding and pathogen attack.Upon perception of pathogens,JA is synthesized and mediates a signaling cascade initiating various defense responses.Traditionally,necrotrophic fungi have been shown to be the primary activators of JA-dependent defenses through the JA-receptor,COI1.Conversely,plants infected with biotrophic fungi have classically been associated with suppressing JA-mediated responses.However,recent evidence has shown that certain biotrophic fungal species also trigger activation of JA-mediated responses and mutants deficient in JA signaling show an increase in susceptibility to certain biotrophic fungal pathogens.These findings suggest a new role for JA in defense against fungai biotrophs.This review will focus on recent research advancing our knowledge of JA-dependant responses involved in defense against both biotrophic and necrotrophic fungi.