Involved in camalexin biosynthesis by probably catalyzing the conjugation of GSH with indole-3-acetonitrile (IAN). May be involved in the conjugation of reduced glutathione to a wide number of exogenous and endogenous hydrophobic electrophiles and have a detoxification role against certain herbicides. glutathione + RX = a halide anion + an S-substituted glutathione + H(+) By dehydration stress, salicylic acid, ethylene, methyl jasmonate, auxin, H(2)O(2), copper, metolachlor, and the pathogens P.syringae and Hyaloperonospora parasitica. Induced by cadmium (PubMed:16502469). No visible phenotype under normal growth conditions, but reduced levels of camalexin production during infection by B.cinerea. Belongs to the GST superfamily. Phi family.