Abstract: Mulberry is one of the suitable species for vegetation restoration in the hydro-fluctuation belt due to its strong resistance of water-logging. To clarify the mechanism of forage mulberry to adapt to submergence in the water-level-fluctuating zone of the Three Gorges Reservoir area, a flooding simulating pot experiment was conducted to examine the changes of leaf morphology,activities of anaerobic respiration enzymes (PDC, ADH, LDH) and antioxidant enzymes (SOD, POD, CAT) in leaves of 2-year-old forage mulberry seedlings under different flooding time and depths. The results showed that the leaf damage degree in the root submergence group was not serious during flooding. While the leaves of deep submergence group appeared wilting and yellowing on the 15th day, the leaves were almost rotten and fall off after flooding. In the deep submergence group, new shoots could still sprout on the 75th day. The recovery growth of some plants in the root submergence group was fine. Under the same flooding time, the activities ofanaerobic respiration enzymes and antioxidant enzymes in leaves showed a significant rising trend with increasing flooding depth (P<0.05). The activity of SOD significantly increased on the 60th day of flooding, and decreased by 3.49% and 9.22% respectively in the control group and root submergence group on the 90th day, while the activity of POD and CAT reached the maximum level on the 90th day of flooding. Compared with the 30th day of flooding, the activities of both enzymes under three treatments on the 90th day of flooding significantly increased by 8.03%, 15.70%,10.23% and 12.05%, 6.45%, 9.15%, respectively (P<0.05). Our results indicate that mulberry seedlings responded to flooding stress through increasing the activities of anaerobic enzymes and antioxidant enzymes and coordinating the three antioxidant enzymes. In conclusion, forage mulberry seedlings have good adaptability to flooding stress and can be used for vegetation restoration in the water-level-fluctuating zone of the Three Gorges Reservoir area.

Key words: wheat (Triticum aestivum), combined application of N and Zn, Zn accumulation, Zn translocation, Zn partitioning