水分胁迫对冷藏韭菜叶片衰老和活性氧代谢的影响

Effect of Water Stress on Senescence and Active Oxygen Metabolism of Leek Blade during Cold Storage

与保水处理韭菜相比,对照(CK)韭菜冷藏期间,失水很快,遭受严重水分胁迫,其叶片叶绿素含量和色调角(hueangle)值显著降低。水分胁迫降低了韭菜抗氧化剂、类胡萝卜素和抗坏血酸含量,抑制了抗氧化酶特别是SOD(超氧化物歧化酶)和CAT(过氧化氢酶)活性,促进了H2O2和膜脂过氧化产物MDA(丙二醛)的积累。采后水分胁迫促进了冷藏韭菜衰老,其机制与水分胁迫促进活性氧代谢失调和膜脂过氧化有关。

Compared with leeks of water preserving, control leeks lost water swiftly, therefore, suffered from severe water stress, and chlorophyll content and Hue angle value were significantly reduced. The content of antioxidant carotene and ascorbic acid of leeks was also reduced, activities of antioxidation enzyme especially SOD(superoxide dismutase) and CAT (catalase)was also decreased,and accumulation in H_2O_2 and MDA(malondialdehyde) was promoted by water stress. It can be concluded that postharvest water stress accelerated senescence of leeks during cold storage,the mechanism was related to promoted maladjustment of active oxygen metabolism and membrane lipid peroxidation by water stress.