大豆叶绿素分子光能吸收特性  

Investigation on the light energy absorption characteristics of chlorophyll molecules for soybean

作　　者：康华靖 李进省 王复标 彭春菊 牛正文 段世华[4] 叶子飘[3] KANG Huajing;LI Jinsheng;WANG Fubiao;PENG Chunju;NIU Zhengwen;DUAN Shihua;YE Zipiao(Key Laboratory of Crop Breeding in South Zhejiang,Wenzhou Academy of Agricultural Sciences,Wenzhou 325006,China;Jiangxi Jinggangshan School of Science and Technology,Ji′an 343000,China;Institute of Biophysics,School of Mathematics and Science,Jinggangshan University,Ji′an 343009,China;School of Life Science,Jinggangshan University,Ji′an 343009,China)

机构地区：[1]温州市农业科学研究院浙南作物育种重点实验室,温州325006 [2]江西省井冈山应用科技学校,吉安343000 [3]井冈山大学数理学院生物物理研究所,吉安343009 [4]井冈山大学生命科学学院,吉安343009

出　　处：《生态学报》2025年第3期1454-1463,共10页Acta Ecologica Sinica

基　　金：国家自然科学基金项目(31960054,32260063)。

摘　　要：明确叶绿素分子有效光能吸收截面对深入了解植物光合过程具有重要意义。为定量且全面探讨光合色素分子有效光能吸收截面对光强的响应,以大豆(Glycine max)为例,设置全日照和遮荫两种光强处理,首先测量CO_(2)浓度分别为300、400、500μmol/mol和600μmol/mol时叶片电子传递速率对光强的响应曲线(J/I曲线);测量大豆叶片的叶绿素含量;然后结合光合机理模型计算本征光能吸收截面(σ_(ik))、有效光能吸收截面(σ′_(ik))和捕光色素分子处于激发态的最小平均寿命(τ_(min))等光合参数。结果表明,光合机理模型可很好地拟合两种光强条件下不同CO_(2)浓度下大豆叶片的J/I曲线,其决定系数均大于0.99;不同CO_(2)浓度下,遮荫和全日照下最大电子传递速率(J_(max))范围分别为126.03-164.34μmol m^(-2) s^(-1)和273.33-326.92μmol m^(-2) s^(-1),τ_(min)值范围分别为16.15-22.93 ms和3.65-4.64 ms。与全日照相比,遮荫条件下大豆叶片捕光色素分子的光能吸收能力明显较低,而处于最低激发态的叶绿素分子数则明显较大。相同光照处理下,不同CO_(2)浓度对大豆叶片的σ_(ik)和τ_(min)值无显著影响,而σ′_(ik)值随着CO_(2)浓度增加而整体呈减小趋势。以400μmol/mol CO_(2)浓度时的相关光合参数为例,结合电子传递速率计算公式,首次从叶绿素分子光能吸收特性角度定量解释了全日照条件下大豆叶片具较高J_(max)的原因。这为定量研究叶绿素分子有效光能吸收截面提供了新的研究手段。Understanding the effective light energy absorption cross⁃section of chlorophyll molecules is crucial for a deeper insight into the complexities of the plant photosynthetic process.This study investigates how the effective energy absorption cross⁃section of chlorophyll responds to varying light intensities,aiming to shed light on the underlying reasons for discrepancies in photosynthetic electron transfer rates among plants exposed to different light conditions.We used a portable photosynthesis fluorescence measurement system to capture the response curve of the electron transfer rate to light intensity(J/I curve)for soybean(Glycine max)leaves under both shaded and full sunlight conditions,with each condition tested across CO2 concentrations of 300,400,500μmol/mol and 600μmol/mol.Concurrently,we measured the chlorophyll content of the soybean leaves to provide a comprehensive dataset.Using a photosynthetic mechanistic model,we calculated key parameters:the intrinsic light absorption cross⁃section(σik),the effective light absorption cross⁃section(σ′ik),and the minimum average lifetime(τmin)of the excited state of the pigment molecules.The mechanistic model showed an excellent fit to the J/I curves of soybean leaves under the tested CO_(2) concentrations and light conditions,with a determination coefficient exceeding 0.99.The fitted results revealed significant differences in the maximum electron transport rate values(Jmax)between shaded and full sunlight conditions across all CO_(2) concentrations.Specifically,Jmax values ranged from 126.03 to 164.34μmol m^(-2) s^(-1) under shade and 273.33 to 326.92μmol m^(-2) s^(-1) under full sunlight.Similarly,τmin exhibited distinct ranges:16.15 to 22.93 ms under shaded conditions and a notably lower range of 3.65 to 4.64 ms under full sunlight.In comparing the two light conditions,the photosynthetic pigment molecules in soybean leaves demonstrated a significantly lower light energy absorption capacity under shade,yet they possessed a higher number of chloro

关 键 词：光能吸收 本征光能吸收截面 有效光能吸收截面 光合机理模型 

分 类 号：S565.1[农业科学—作物学]