Abstract: Taking two summer maize hybrids Zhengdan 958 (ZD958) and Denghai 605 (DH605) as experimental materials, a field experiment was conducted to explore the effects of waterlogging for different durations (3 and 6 days) on leaf senescence characteristics of summer maize at the three-leaf stage (V3), six-leaf stage (V6), and 10 days after the tasseling stage (10VT). Results showed that superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) activities and soluble protein content decreased significantly after waterlogging. However, the content of malondialdehyde (MDA) increased significantly by 35.3% and 34.1% for DH605 and ZD958, respectively. The leaf chlorophyll content and grain yield of summer maize decreased significantly after waterlogging. The grain yields of DH605 and ZD958 after waterlogging for 6 days at V3 were most seriously affected, which were decreased by 32.1% and 35.2%, respectively. Overall, the summer maize was most susceptible to the effect of waterlogging at V3, followed by V6 and 10VT, and the influence extent increased with the increase of waterlogging duration.

Key words: summer maize, field waterlogging, leaf senescence characteristics, grain yield.