木霉对盐胁迫下枸杞根与叶内离子平衡和光系统Ⅱ的影响  

Effects of Trichoderma on Root and Leaf Ionic Homeostasis and PhotosystemⅡin Chinese Wolfberry Under Salt Stress

作　　者：边兰星 梁丽琨[1] 颜坤[2,3] 宿红艳 李丽霞 董小燕[2] 梅惠敏 BIAN LanXing;LIANG LiKun;YAN Kun;SU HongYan;LI LiXia;DONG XiaoYan;MEI HuiMin(College of Life Science,Yantai University,Yantai 264003,Shandong;Key Laboratory of Coastal Environmental Processes andEcological Remediation,Chinese Academy of Science Yantai Institute of Coastal Zone Research/Chinese Academy of Sciences,Yantai264003,Shandong;College of Agriculture,Ludong University,Yantai 264003,Shandong;College of life science,Liaoning University,Shenyang 110000)

机构地区：[1]烟台大学生命科学学院,山东烟台264005 [2]中国科学院烟台海岸带研究所/中国科学院海岸带环境过程与生态修复重点实验室,山东烟台264003 [3]鲁东大学农学院,山东烟台264025 [4]辽宁大学生命科学院,沈阳110000

出　　处：《中国农业科学》2022年第12期2413-2424,共12页Scientia Agricultura Sinica

基　　金：国家重点研发计划(2019YFD1002702);NSFC-山东联合基金(U2106214);烟台市科技创新发展计划(2020MSGY065)。

摘　　要：【目的】研究木霉对枸杞(Lycium chinense)耐盐能力的影响,从离子平衡、氧化胁迫和光系统Ⅱ(PSⅡ)性能等方面揭示耐盐机理。【方法】以枸杞为试验材料,施加木霉菌剂于根周围,浇灌NaCl溶液(300 mmol·L^(-1))进行盐处理,比较盐胁迫下施加和未施加菌剂植株生物量、K^(+)/Na^(+)、根系钾钠离子吸收转运、叶片氧化损伤以及PSⅡ性能的差异。【结果】盐胁迫下,施加菌剂的植株生物量降幅较小,说明木霉能够提高枸杞耐盐能力,减少对生长的抑制。木霉缓解盐诱导的光合速率与PSⅡ光化学效率的下降,抑制PSⅡ激发压上升,有利于防御PSⅡ光抑制。盐胁迫下施加菌剂的植株PSⅡ最大光化学效率的降幅和PSⅡ反应中心蛋白损失相对较少,证实了木霉缓解PSⅡ光抑制,保护了PSⅡ反应中心。与光抑制结果一致,盐胁迫下施加菌剂植株叶片膜脂过氧化程度和H_(2)O_(2)含量较低,氧化损伤较轻。盐胁迫下,施加菌剂植株光合电子传递到Q_(A)以下电子受体效率的降幅较小,叶绿素快速荧光诱导动力学(OJIP)曲线的J点也未明显上升,表明木霉保护了PSⅡ受体侧电子传递体。木霉对PSⅡ供体侧放氧复合体也起到保护作用,因为施加菌剂抑制了盐胁迫下K点相对可变荧光的显著上升以及避免了OJIP曲线中K点的出现。因此,木霉对PSⅡ各组分都起到了保护作用,缓解了盐胁迫下PSⅡ性能指数的下降,提高了PSⅡ整体稳定性。盐胁迫下,施加菌剂的植株根和叶Na^(+)含量较低,但K^(+)含量较高,说明木霉通过减少根和叶中Na^(+)积累及K^(+)损失,缓解K^(+)/Na^(+)下降,维持离子平衡。木霉增强盐胁迫下根系Na^(+)外排,保障根系K^(+)吸收和向地上部转运,是维护枸杞离子平衡的关键机制。【结论】木霉调控盐胁迫下根系钠钾离子吸收转运,维持离子平衡,减轻PSⅡ氧化胁迫,增强枸杞耐盐能力,缓解对其生长的抑制。【Objective】This research aimed to investigate the effect of Trichoderma on salt tolerant ability of Chinese wolfberry(Lycium chinense),and to reveal the salt tolerant mechanisms in terms of in ion homeostasis,oxidative stress and photosystemⅡ(PSⅡ)performance.【Method】Chinese wolfberry was used as the experimental material,and Trichoderma agent was applied around roots.Salt treatment was carried out by irrigation with NaCl solution(300 mmol·L^(-1)),so as to compare the differences of biomass,K^(+)/Na^(+),K^(+)and Na^(+) absorption and transport in roots,leaf oxidative damage and PSⅡperformance in plants applied with and without Trichoderma agents under salt stress.【Result】Under salt stress,the biomass decreased less in plants applied with Trichoderma agents,indicating that Trichoderma could improve salt tolerance in Chinese wolfberry and alleviate the inhibition on growth.Under salt stress,Trichoderma alleviated the decline of photosynthetic rate and actual photochemical efficiency of PSⅡ,inhibited the elevation of PSⅡexcitation pressure,and aided in defending PSⅡphotoinhibition.The decrease in Fv/Fm and the loss of PSⅡreaction center protein were relatively less in plants applied with Trichoderma agents under salt stress,confirming that Trichoderma alleviated PSⅡphotoinhibition and protected PSⅡreaction center.Consistent with the result of photoinhibition,the oxidative damage was slighter in plants applied with Trichoderma agents according to lower leaf lipid peroxidation extent and H_(2)O_(2) content.Under salt stress,the lower decrease in the efficiency that an electron moved beyond Q_(A) was noted in plants with Trichoderma agents application,while J step of chlorophyll a fluorescence transient(OJIP)did not obviously rise,indicating that Trichoderma protected the electron transporters at PSⅡacceptor side.Trichoderma also protected oxygen-evolving complex at PSⅡdonor side of PSⅡ,because the application of Trichoderma agent prevented a significant increase in variable fluoresc

关 键 词：木霉菌剂 枸杞 耐盐能力 光抑制 非损伤微测技术 

分 类 号：S567.19[农业科学—中草药栽培]