三种UV-B辐射强度下香蒲叶片光合特性和叶绿体超微结构及其变化  

Photosynthetic Characteristics and Chloroplast Ultrastructure of Typha orientalis Leaves under 3 Kinds of UV-B Radiation Intensities and Their Changes

作　　者：褚润[1] 陈年来[1] 韩国君[1] 李良[1] CHU Run;CHEN Nianlai;HAN Guojun;LI Liang(College of Resources and Environment,Gansu Agricultural University,Lanzhou 730070,Gansu,P.R.China)

机构地区：[1]甘肃农业大学资源与环境学院,甘肃兰州730070

出　　处：《湿地科学》2021年第2期147-153,共7页Wetland Science

基　　金：甘肃农业大学学科建设专项基金项目(GAU-XKJS-2018-210);甘肃省重点研发计划项目(18YF1FA078)资助。

摘　　要：为了探究3种UV-B(ultraviolet-B,波长为280~315 nm的紫外光)辐射强度对香蒲(Typha orientalis)叶片光合特性和叶绿体超微结构的影响,于2017年5月19日至7月17日,在甘肃农业大学室外实验基地,构建模拟垂直潜流人工湿地,在其中栽种香蒲幼苗;在3种UV-B辐射强度[168μw/cm^(2)(自然光照下)、210μw/cm^(2)和252μw/cm^(2)]下,测定香蒲叶片光合色素含量和光合特性指标,并观察其叶绿体超微结构。研究结果表明,UV-B辐射增强显著减小了香蒲叶片的光合色素含量,且随着辐射强度增大,光合色素含量减小量增大;UV-B辐射增强显著减小了香蒲叶片的净光合速率、气孔导度和蒸腾速率,增大了胞间CO_(2)浓度,UV-B辐射强度增强的条件下香蒲叶片光合速率减小的主要原因是非气孔因素;在UV-B辐射增强条件下,香蒲叶片叶绿体超微结构遭到破坏,表现为叶绿体数目减少,叶绿体结构变形,体积膨大,形态臃肿,叶绿体中出现淀粉颗粒,破坏作用随辐射强度增大而加剧。In order to explore the effects of three kinds of UV-B radiation intensities on photosynthetic pigments,photosynthetic characteristics and chloroplast ultrastructure of Typha orientalis,from May 19 to July 17,2017,a simulated vertical subsurface flow constructed wetland was constructed in the outdoor experimental base of Gansu Agricultural University,in which Typha orientalis seedlings were planted.Photosynthetic pigment content and photosynthetic characteristics of Typha orientalis were measured under three kinds of UV-B radiation intensities(168μw/cm^(2),210μw/cm^(2) and 252μw/cm^(2)).Chloroplast ultrastructure of Typha orientalis leaves was observed.The results showed that enhanced UV-B radiation significantly reduced photosynthetic pigment contents,and the degree of degradation increased with the increasing irradiation intensity.Enhanced UV-B radiation significantly decreased the net photosynthetic rate,stomatal conductance and transpiration rate while intercellular CO_(2) increased,which suggested that the main reason for photosynthesis decrease is the nonstomatal factors.Under enhanced UV-B radiation,the ultrastructure of chloroplast was destroyed,the number of chloroplast decreased,the chloroplast deformed,the volume expanded,the shape bloated,the starch granules emerged and the damage increased with the increase of radiation intensity.

关 键 词：香蒲 UV-B辐射 光合色素含量 光合特性 叶绿体超微结构 

分 类 号：X171.5[环境科学与工程—环境科学] Q948.1[生物学—植物学]