黄化茶树叶片光合及荧光特性分析

Analysis of Photosynthetic and Fluorescence Characteristics of Albino Tea Plants

以3个叶色黄化茶树品种为研究材料,以绿色系茶树品种福鼎大白茶为对照,研究黄化茶树的光合色素含量、光合及叶绿素荧光诱导动力学特性的变化,为叶色黄化茶树品种的种质评价及栽培管理提供科学指导。结果表明:(1)黄化茶树叶片叶绿素总量比对照茶树品种低71.7%~86.8%,类胡萝卜素总量维持在0.16~0.31 mg·g^(-1)。(2)3个黄化茶树品种的净光合速率、气孔导度、水分利用效率、最大净光合速率和光饱和点等光合参数显著降低,光补偿点显著高于对照茶树品种。(3)黄化茶树叶片对光能的吸收、转化与利用等光合过程与对照茶树品种差异显著,其中金凤2号和中黄1号叶片快速叶绿素荧光动力学曲线中的L点和J点相对可变荧光显著升高;叶绿素荧光动力学参数M_(O)、DI_(O)/RC、φD_(O)和φR_(O)等显著增加,F_V/F_(O)、ET_(O)/RC、φP_(O)、φE_(O)、ΨE_(O)和PI_(abs)等显著降低。研究认为,黄化茶树叶片光合效率、潜力及生态适应能力均显著降低;其中,茶树黄化叶片光合色素显著减少、PSⅡ光能捕获及光合电子传递效率显著下降,热耗散能量显著增加,是导致其光合作用综合性能降低的重要原因。

To facilitate the scientific assessment of germplasm evaluation and cultivation management of albino tea plants(Camellia sinensis L.),this study investigated the photosynthetic pigment contents,as well as the photosynthetic and chlorophyll fluorescence characteristics of three albino cultivars,with the normal tea cultivar‘Fuding dabaicha’(FD)as the control.The results show that(1)the total chlorophyll content of yellow tea leaves was 71.7%-86.8%lower than that of the control cultivar,and the total carotenoid content remained between 0.16 mg·g^(-1) and 0.31 mg·g^(-1).(2)The net photosynthetic rate(P_(n)),stomatal conductance(G_(s)),water use efficiency(WUE),the maximum net photosynthetic rate(Pn max),and light saturation point(LSP)of three albino tea cultivars were significantly decreased,and the optical compensation point(LCP)was significantly was than those of the control.(3)The photosynthetic processes of albino tea cultivars,such as absorption,transformation and consumption of light energy were significantly different from those of the control.Among them,the relative variable fluorescence at L and J points in the OJIP curve of albino tea cultivars‘Jinfeng 2’(JF2)and‘Zhonghuang 1’(ZH1)were significantly higher.Among the chlorophyll fluorescence kinetic parameters,MO,DI_(O)/RC,φD_(O) and φR_(O) increased significantly,while F_(V)/F_(O),ET_(O)/RC,φP_(O),φE_(O),ΨE_(O) and PIabs decreased significantly.Our study found that the photosynthetic efficiency,potential and ecological adaptability of albino tea leaves were significantly decreased.The significant reduction of photosynthetic pigment,the significant decrease of PSⅡlight capture and photosynthetic electron transfer efficiency,and the significant increase of heat dissipation energy were the considerable reasons for inhibition of photosynthetic performance in albino tea plants.