摘要： 研究了不同光强对紫罗勒花青素含量、气体交换、叶绿素荧光特性及反射光谱的影响.结果表明:强光下紫罗勒叶片较厚,而弱光下叶片较薄.与弱光下生长的紫罗勒相比,强光下单位叶面积叶绿素含量和花青素含量较高、叶片光补偿点和光饱和点升高、表观量子效率下降、净光合速率(Pn)明显提高、最大光化学效率(Fv/Fm)和光系统Ⅱ性能参数(PI)增大,同时,天线转化效率(Fv′/Fm′)、光化学猝灭系数(qP)、实际光化学效率(φPSⅡ)升高,而非光化学猝灭(NPQ)降低;叶片光化学反射指数(PRI)下调幅度较小.由此,可以认为光强通过影响紫罗勒叶片厚度、比叶面积、色素含量、光系统Ⅱ性能从而改变其光合能力;提高光合能力和花青素含量有助于紫罗勒适应强光环境.

关键词: 紫罗勒, 气体交换, 叶绿素荧光, 花青素, 叶黄素循环

Abstract: Anthocyanins contents,gas exchange,chlorophyll a fluorescence kinetics and reflectance spectroscopy of leaves under different light intensity were investigated in purple basil leaves.The results indicated that the leaves became thick under the high light and became thin under the weak light.Compared with the purple basil grown under the weak light,the chlorophyll and anthocyanins content per leaf area were significant increased under the high light.In addition,the plant grown under the high light,the light compensation point(LCP) and light saturation point(LSP)were significantly raised;the apparent quantum yield(AQY),net photosynthetic rate(Pn),maximal photochemical efficiency(Fv/Fm) and photosystem II capability index(PI)sharply increased;the efficiency of open centers of photosystem II(Fv′/Fm′),photochemical quenching(qP)and actual photosystem II efficiency(ΦPSII) gradually enhanced,while non-photochemical quenching(NPQ) decreased;the photochemical reflectance index(PRI) of leaves were slightly down regulated.On these bases,we concluded that light intensity to regulate photosynthetic capacity by way of influencing leaves thickness,specific leaf area,pigment content,photosystem II activity;The enhanced of photosynthetic capacity and anthocyanins contents is beneficial to relieve strong light stress in purple basil leaves.

Key words: Purple basil, Gas exchange, Chlorophyll fluorescence, Anthocyanins, Xanthophyll cycle

中图分类号: 

• S6