Abstract:In a nutrient solution hydroponic conditions,effect of foliar pre-application of 5% (V/V) methanol on the contents of H2O2 and MDA,and antioxidant enzyme activities (SOD,POD and CAT) in leaf and root of black soybean ［Glycine max (L.) Merrill］ were investigated under 50 μmol·L-1 Al3+ stress,and to lay the foundation for further studying on the regulatory mechanism of methanol and antioxidant enzymes response to Al stress.The results showed that:(1)Under Al stress,the absorption amount of aluminum from root tips was more with increasing Al3+ treatment concentration,and the root growth was more seriously inhibited.(2)Al stress could induce the increasing of the contents of soluble protein,H2O2 and MDA,POD and CAT activities in leaf and root of black soybean,but SOD activity was no significantly change.(3)After foliar pre-application of 5% methanol treatment,under 50 μmol·L-1 Al3+ stress the contents of soluble protein,POD and CAT activities were significantly ascend with increasing treatment time,while the contents of H2O2 and MDA in leaf and root were declined,and SOD activity was also no change.The study results have shown that foliar application of 5% methanol could significantly increase antioxidant enzyme activities (CAT and POD),and decline the accumulation of H2O2 and MDA in leaf and root of black soybean under Al stress.This may be an important mechanism for methanol taking part in response to Al stress by regulating antioxidant enzyme activities.