Physiology Effects of Light Quality on Leaf Senescence in Flue-cured Tobacco Leaves
To investigate the mechanism involved in the different responses of flue-cured tobacco leaf senescence to light qualities,the interaction effects of different lights on plastid pigment metabolism and activities of antioxidant enzymes in the maturation of flue-cured tobacco leaves were investigated.Taking Yunyan 87 (Ntcotiara tobacum L.) as test material,by covering red,white,blue,yellow and purple polyethylene films above tobacco plants to obtain different light quality.Results indicated that plastid pigments were degradating and translating after topping.Compared with natural light,red and white light significantly inhibited the degradation of chlorophyll.White and blue light inhibited the degradation of caroteniods.Sequence of pigment degradation rate under different lights during declined stage was blue ＞ yellow ＞ purple ＞ red ＞ white ＞ nature light.The activities of antioxidant enzymes in leaves demonstrated the trend of increased first and then decreased.Yellow and red light increased the activities of antioxidant enzymes,and made the content of MDA at a relatively low level.In contrast,purple and blue light decreased the activities of antioxidant enzymes and led to higher contents of MDA in the leaves.In summary,red light treatment contributed to accumulation,and blue light treatment contributed to degradation.Yellow and red light could maintain high levels of antioxidant enzymes and delay aging of flue-cured tobacco leaves.
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万方数据
维普
