烤烟叶片成熟与衰老生理特性研究

Studies on physiological traits of ripeness and senescence in flue-cured tobacco leaves

通过对烟叶成熟与衰老密切相关的膜脂过氧化系统研究发现,在烟叶成熟与衰老过程中,叶绿素和类胡萝卜素含量持续降低,前者降解速率较快,打顶后SOD活性先降后升,下二棚叶适熟后,SOD活性持续上升,其它叶位则呈现下降,POD活性和Pr含量逐渐降低,MDA活性逐渐升高;在下二棚叶尚熟至适熟时是膜脂过氧化与抗氧化平衡转折的关键时期。

Cell membrane-lipid peroxidation and endogenous protective enzymes activity in relation to leaf maturity of flue-cured tobacco were studied in this paper. During ripeness and senescence of tobacco leaf, contents of chlorophyll and carotenoid were continously degraded, with the degradation rate of the former more fast. After topping, SOD activities declined firstly, then went up, in lower leaves sustaining rose after ripeness of lower leaves, at the same time leaves of the other locations were reverse. POD activities and contents of Pr dropped off, and MDA contents gradually rose. The key periods when the cell membrane-lipid peroxidation and anti-oxygenation reach balance were from maturation to ripeness.