Abstract: Aluminum toxicity is one of the major factors limiting crop production in acidic soils. Sweet corn （Zea mays L.） inbred lines breeding for aluminum toxicity tolerance is an effective way to solve this problem. To determine the identification method of aluminum toxicity tolerance and screen sweet corn lines with aluminum toxicity tolerance is of importance for aluminum toxicity tolerant breeding. 5 sweet corn lines with different growth vigor were selected to identify the aluminum toxicity tolerance by nutrient solution culture. The concentrations of aluminum ions were 0, 0.1, 0.2, 0.3 and 0.4 mmol/L, respectively. The fresh weight and dry weight of stems and leaf and root were measured on the 7th, 10th and 14th day after treated by aluminum toxicity. The results showed that the growth of stem, leaf and root of sweet corn slowed down with the increase of treatment concentration, and the results of aluminum resistance test on the 7th and 10th day of treatment were relatively consistent, in which, G107 and G139 showed the best tolerance to aluminum toxicity, G118 and G151 were in the middle level, and G79 showed the worst tolerance to aluminum toxicity. The activities of POD, CAT and SOD were detected at 14th day after treated by different concentration of aluminum ions, that the activity of three enzymes increased at low concentration, and then decreased with the increase of stress concentration.

Key words: sweet corn （Zea mays L.）, aluminum toxicity, POD, CAT, SOD