AAL toxin (the major virulence factor of Alternaria alternata f. sp. lycopersici)was treated to wild type(Col-0)and transgenic Arabidopsis with enhanced GSH (AtECS1). A proteomic profile was obtained by nano LC-MS/MS analysis.Among the identified proteins, a few proteins were selected for qRT-PCR and western blot analysis. It was found that AAL mediated resistance in plants can be conferred by GSH through SA and ET mediated pathways, in addition to several stress responsive molecules.