In vitro, possesses glutathione S-transferase activity toward 1-chloro-2,4-dinitrobenzene (CDNB) and benzyl isothiocyanate (BITC). 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 auxin. Belongs to the GST superfamily. Tau family.