滤减UV B辐射对烟叶可溶性蛋白、〖HJ*3〗〖HJ*2〗光合色素和类黄酮的影响

在云南玉溪烟区种植烤烟海拔最高(1806.0m)的通海县,通过盆栽烤烟K326试验,研究了在滤减自然的太阳UV-B辐射强度25%、50%和65%条件下,UV-B辐射对烟叶发育过程中可溶性蛋白、光合色素和类黄酮的影响。结果表明:随叶龄增加,可溶性蛋白含量下降,光合色素降解,类黄酮在老叶中积累,蛋白质在生理成熟期对UV-B辐射最敏感。与对照相比,减弱UV-B辐射处理降低了烟叶类黄酮和可溶性蛋白含量,但光合色素含量上升;较低的UV-B辐射降低了叶绿素的降解速度。结果从一侧面说明UV-B辐射对烟叶蛋白质的合成是有益的,类黄酮和叶绿素的变化是对UV-B辐射变化的适应性反应,类黄酮与蛋白质之间可能存在一定的偶联关系。

Effects of attenuated ultraviolet-B radiation on soluble protein,photosynthetic pigments and flavonoids in tobacco leaves

Tobacco variety K326 were planted in pots under attenuated 25%,50% and 65% of solar UV-B radiation conditions,respectively in Tonghai,Yunnan of China,where is on the highest altitude in Yuxi tobacco cultivation region. The effects of UV-B radiation on soluble protein,potosynthetic pigment and flavonoid in tobacco leaves were studied in different K326 growth periods. The results showed that,soluble protein and potosynthetic pigment contents decreased along with leaf aging,flavonoid accumulated in old leaves. Protein was susceptible to UV-B radiation in physiological maturity period. Reduced UV-B radiation resulted in decrease of the flavonoid and protein contents,but result in increase of potosynthetic pigment content. Lower UV-B radiation led to decreases of the chlorophyll degradation rate. Therefore,it could be speculated that UV-B might be beneficial for protein accumulation in tobacco; and alteration of flavonoid and chlorophyll could be adaptable modifications in response to UV-B radiation. In addition,flavonoid might couple with soluble proteins in a certain extent.