绿竹滩涂地造林的快速叶绿素荧光动力学分析

An Analysis of Fast Chlorophyll Fluorescence Induction Dynamics of Bambusa oldhami on Intertidal Zone

研究以绿竹为试材,在飞云江上游淤积的正常耕作土壤(对照)和下游江边滩涂地(盐胁迫)造绿竹林,采用非调制式叶绿素荧光仪进行光系统Ⅱ(PSⅡ)快速叶绿素荧光诱导动力学参数测定分析(OJIP-test)。结果表明:正常耕作土壤生长的绿竹,随着竹秆年龄的增长,单位面积光合机构含有的反应中心数目(RC/CSo)呈增加趋势;叶绿素含量和单位反应中心以热能形式耗散的能量(DIo/RC)呈下降趋势。在滩涂地生长的绿竹,1年生竹秆的叶片叶绿素含量和Fv/Fm与对照相比分别降低了18.03%和7.56%,RC/CSo与对照相比增加了35.86%;随着绿竹秆年龄的增长差异减小;1年生绿竹秆的叶片DIo/RC值与对照无明显差异,随着绿竹秆年龄的增加差异增大。综合分析表明绿竹适应盐胁迫过程是通过增加PSⅡ反应中心的可逆失活和热耗散在保护PSⅡ防止光抑制中起到重要作用。

Dendrocalamopsis oldhami （Gramineae, Bambusoideae） is a species of sympodial bamboo. It is widely cultured in beach and mountain areas owing to its good properties, high shoot productivity, rapid growth and high salt tolerance. In April 2007, the D. oldhami were planted respectively in the intertidal lower reaches （the salt stress ） and in the common cultivated soil in upper reaches （the control） of Feiyunjiang River. In November 2009, their chlorophyll fluorescence parameters of Photosystem II （ PS II ） were detected. The results indicated that the maximum photochemical efficiency （Fv/Fm ） and RC/CSo under both treatments continued to increase with the age, whereas the tendency of the chlorophyll content and DIo/RC were opposite. For the leaves of one-year-old D. oldhami, the values of RC/CSo of those under salt stress were 35.86% higher than that of the control, while the chlorophyll content and Fv/Fm were respectively 18.03% and 7.56% less than that of the control. With the increase of age, there showed a gradually small difference in Fv/Fm, RC/CSo, chlorophyll content of D. oldhami leaves between two treatments. The tendency of DIo/RC content was contrary, although there was no difference in DIo/RC content of one-year-old D. oldhami under two treatments. These suggested that D. oldhami had stronger adaptation to salt stress owing to improving the reversible inactivation of PS II reaction centers and dissipating excessive heat in the process of protecting the PS lI from being damaged.