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烤烟叶片在不同发育阶段，其内源ＳＯＤ及ＣＡＴ，活性和膜脂过氧化作用和细胞膜透性表现出不同的变化速度，从未熟经欠熟到适熟阶段，ＳＯＤ和ＣＡＴ活性下降缓慢，膜脂过氧化作用及细胞膜透性提高幅度较小；在适熟期之后，ＳＯＤ和ＣＡＴ活性急剧下降，膜脂过氧化水平和细胞膜透性急剧提高。表明烟叶的成熟衰老与体内活性氧代谢密切相关，适熟期是叶片由功能期转向衰老的关键时期。在烟叶成熟过程中，脂肪酸含量发生明显变化。随着成熟度的提高，月桂酸含量增加，棕榈油酸、油酸和二十碳烯酸含量下降，而十三烷酸、十四烷酸、棕榈酸、硬脂酸和亚油酸的含量在适熟期最高。
Flue-cured tobacco leaf showed different rate of change in endogenous SOD and CAT activity, membrane lipid peroxidation and membrane permeability at different developmental stages. The activity of SOD and CAT decreased slowly from immature ripening to mature stage, Lipid peroxidation and cell membrane permeability increased less. After the proper ripening stage, the activities of SOD and CAT decreased sharply, and membrane lipid peroxidation and membrane permeability increased sharply. The results showed that the mature senescence of tobacco leaves was closely related to the active oxygen metabolism in vivo, and the suitable maturity stage was the key period of the leaves turning from senescence to senescence. During the ripening of tobacco leaves, the content of fatty acids changed obviously. With the increase of maturity, the content of lauric acid increased, the content of palmitoleic acid, oleic acid and eicosenoic acid decreased while the content of tridecanoic acid, myristic acid, palmitic acid, stearic acid and linoleic acid In the most suitable stage.