Mutants are important materials to study the function of disease-related genes. In this study, the mutant was derived from cv Yuanza 9102 treated with EMS. Yuanza 9102 was selected from an interspecific cross of cv Baisha 1016 with A. diogoi, and resistant to several fungal disease, while mutant was highly susceptible to late leaf spot. RNA-Seq analysis in the leaf tissues of the mutant and its wild type Yuanza 9102 under pathogen challenge .