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PEG模拟水分胁迫过程中,在胁迫强度较轻、胁迫时间较短、胁迫速度缓慢时,玉米幼苗叶片相对含水量 (RWC) 下降较慢,超氧化物歧化酶 (SOD)过氧化氢酶 (CAT)、过氧化物酶 (POD) 活性上升,脂质过氧化作用较轻,膜相对透性增加较小;在胁迫强度较重、胁迫时间较长、胁迫速度较快时,玉米叶片RWC下降较快,SOD、CAT活性下降、脂质过氧化作用加强、膜透性增大。抗旱性不同的两品种在RWC、质膜透性、丙二醛 (MDA) 含量、SOD、CAT、POD活性上存在着明显的差异。这表明水分胁迫过程中,叶片保护酶系统和脂质过氧化作用、膜透性间存在着一定的相互关系。
During the process of simulated water stress, the relative water content (RWC) of maize seedlings decreased slowly under the condition of light stress, short duration of stress and slow stress, and the activities of superoxide dismutase (SOD) catalase (CAT) ), The activity of peroxidase (POD) increased, the lipid peroxidation was lighter, and the relative permeability of the membrane increased less. Under the conditions of severe stress, longer duration of stress and faster stress, RWC of maize leaf decreased more Fast, SOD, CAT activity decreased, lipid peroxidation strengthened, membrane permeability increased. There was a significant difference in RWC, plasma membrane permeability, malondialdehyde (MDA) content, SOD, CAT and POD activity between two cultivars with different drought resistance. This indicates that during water stress, there is a certain correlation between the protective enzyme system and lipid peroxidation and membrane permeability.