干旱胁迫及复水对红松针叶和树皮绿色组织光合特性及抗氧化系统的影响  

Response of photosynthetic characteristics and antioxidant system in needles and bark chlorenchyma of Korean pine to drought stress and rehydration

作　　者：张丹[1] 任洁[1] 王慧梅[1] ZHANG Dan REN Jie WANG Hui-Mei(Key Laboratory of Forest Plant Ecology, Northeast Forestry University, Harbin 150040, China）.)

机构地区：[1]东北林业大学森林植物生态学教育部重点实验室,哈尔滨150040

出　　处：《生态学杂志》2016年第10期2606-2614,共9页Chinese Journal of Ecology

基　　金：中央高校基本科研业务费专项(DL13 EA03-03);国家自然科学基金项目(31100457);黑龙江省自然科学基金项目(C2015051)资助

摘　　要：以红松为材料,研究了干旱及复水对红松针叶和树皮绿色组织的光合特性和抗氧化酶活性等生理生化指标的影响。结果表明:干旱胁迫下,红松针叶和树皮绿色组织叶绿素总量和叶绿素a/b值均有显著下降,这样可以通过降低PSII天线捕获的光能,减少发生光抑制的危险;针叶净光合速率(Pn)下降主要由非气孔因素造成,树皮绿色组织Pn下降主要由气孔因素造成;红松针叶和树皮绿色组织非光化学猝灭(NPQ)均升高,表明热耗散是植株重要光保护机制;红松针叶和树皮绿色组织丙二醛(MDA)含量明显升高,发生了氧化胁迫,超氧化物歧化酶(SOD)等抗氧化酶活性的提高对红松的干旱胁迫起到了积极的防御作用;复水后,红松针叶和树皮绿色组织Pn恢复到对照水平,叶绿素荧光参数和抗氧化酶活性也表现出不同程度恢复。以上研究结果表明,干旱胁迫下红松针叶和树皮绿色组织均通过减少光捕获、热耗散和酶活性调节协同作用,稳定光合机构功能,复水后红松光合特性表现较好的恢复能力,红松对干旱具有较强的适应能力。The effects of drought stress and rehydration on photosynthetic characteristics and antioxidant enzyme activities of needles and bark chlorenchyma of Korean pine were studied. The results showed that the total chlorophyll content and chlorophyll a/b of needles and bark chlorenchyma decreased significantly under drought stress, reducing the PSII antenna to capture light energy and thus the risk of photoinhibition. The main reason for restricting net photosynthetic rate （Pn） of needles was non-stomatal limitation and the main reason for restricting P, of bark chlorenchyma was stomatal limitation. Non-photochemical quenching （NPQ） of needles and bark chlorenchyma were significantly increased under drought stress, indicating that thermal dissipation is an important photoprotection mechanism. Malondialdehyde （MDA） contents in needles and bark chlorenchyma were significantly increased under drought stress, resulting in oxidative stress. Increased SOD activity played an active role in drought stress defense of pine. After rehy- dration, Pn of needles and bark chlorenchyma recovered to the level of the control. Chlorophyll fluorescence parameters and antioxidant enzyme activities also recovered to varying degrees. These results suggest that needles and bark chlorenchyma of Korean pine can stabilize the photosynthetic apparatus function by enhancement of thermal dissipation and antioxidant enzyme activity, and that Korean pine has a good recovery after rehydration and strong adaptability to drought stress.

关 键 词：干旱 复水 针叶 树皮绿色组织 叶绿素荧光 气体交换 抗氧化酶 

分 类 号：S791.247[农业科学—林木遗传育种]