文献类型：期刊文献

中文题名：土壤水分胁迫对欧李幼苗光合及叶绿素荧光特性的影响

英文题名：Effects of Soil Water Stress on the Photosynthesis Characteristics and Chlorophyll Fluorescence Parameters of Cerasus humilis Seedling

作者：褚建民[1] 孟平[1] 张劲松[1] 高峻[1]

第一作者：褚建民

机构：[1]中国林业科学研究院林业研究所,国家林业局林木培育重点试验室,北京100091

年份：2008

卷号：21

期号：3

起止页码：295-300

中文期刊名：林业科学研究

外文期刊名：Forest Research

收录：CSTPCD;;Scopus;北大核心:【北大核心2004】；CSCD:【CSCD2011_2012】；

基金：国家“十五”科技攻关课题(2001BA510B04);退耕还林科技支撑项目资助

语种：中文

中文关键词：水分胁迫;干旱胁迫;光合速率;叶绿素荧光;水分利用效率

外文关键词：soil water stress ; drought stress ; photosynthesis rate ; chlorophyll fluorescence ; water use efficiency

分类号：Q945.1

摘要：采用Li-6400光合仪和OS1-FL调制荧光仪分析研究了水分胁迫下欧李的光合特性和叶绿素荧光参数变化特征。结果表明：（1）在低度水分胁迫下欧李的平均光合速率最大，而在严重水分胁迫下则最小；欧李的气孔导度在无水分胁迫下随光合有效辐射的增强而增大，但在中度水分胁迫和严重水分胁迫下变化不明显。欧李的光合速率日变化呈双峰曲线，中午存在明显的光合午休现象。在低度水分胁迫、无水分胁迫、中度水分胁迫和严重水分胁迫下，欧李的净光合速率分别为8．447±0．831、6．811±0．690、2．658±0．756、1．474±0．469μmol．m^-2·s^-1，前2种条件下与后2种条件下的净光合速率存在极显著差异。不同水分胁迫下欧李的气孔导度、蒸腾速率、水分利用效率的日变化与净光合速率的变化类似。（2）荧光参数初始荧光与非光化萃灭随干旱胁迫程度的增加而增加，而最大光化量子产量、光系统Ⅱ潜在活性则均降低。这表明随水分胁迫程度的增加，PSⅡ反应中心受到破坏或可逆失活，光合作用原初反应过程受抑制，欧李可能通过热耗散消耗掉过剩光能，从而保护了光合机构，这是植物对环境的适应性反应。（3）低度水分胁迫即土壤含水量为21％～24％时，欧李光合生理指标达到最佳水平，水分利用效率最高（1．214±0．112μmol·mmol^-1）。
Both Li-6400 photosynthesis system and OS1-FL chlorophyll fluorometer were used to measure the photosynthesis characteristic and chlorophyll fluorescence parameters of Cerasus humilis plant under soil water stress. The result showed： （1）The average photosynthesis rate reached the maximum under the low water stress , while that under the high soil water stress was the least. The stomatal conductance increased as a result of the increasing of PAR （ Photosynthetically Active Radiation ） under no soil water stress conditions and didn＇ t variate under the mediums and high soil water stress conditions. Diurnal variation of photosynthesis rate presented a twopeaks curve and showed obvious noon depression. The variation of net photosynthesis rates under different water stress conditions are follows： 8. 447 ±0. 831,6. 811± 0. 690,2. 658 ± 0. 756,1. 474 ± 0. 469μmol · m^-2 · s^1 Significant variations of Pn happened between the conditions of the former two and the later two, Diurnal variations of Cond, Tr, WUE under different soil water stress conditions were similar to the variations of Pn. （2） The fluorescence parameter of Fo, NPQ increased with the increasing of water stress, while the Fv/Fm, Fv/Fo dereased.It means that with the increasing of the water stress, the reaction center of PSII was destroyed or a non-reversible deactivation occurred so that the photosynthesis was restrained. The photosynthetic apparatus of C. humilis was protected by exhausting the extra light energy through heat dissipation. （3） WUE reached its maximum（ 1. 214 ± 0.112 μmol· mmol^ - 1 ） and the physiological parameters of photosynthesis were optimized under low soil water stress with water contents from 21% -24%.