摘要
【目的】研究环境相关浓度微囊藻毒素-LR(MC-LR)慢性胁迫对水雍菜(Ipomoea aquatica)叶片光合系统的影响,为阐明低质量浓度MC-LR慢性暴露对水雍菜生长的影响机制提供理论依据。【方法】以含不同质量浓度(0(CK),1,10,30μg/L)MC-LR的营养液培养水雍菜30 d,通过小雍菜叶片叶绿素SPAD值、叶绿素荧光参数、H 2O 2含量、1,5-二磷酸核酮糖羧化酶(Rubisco)及Rubisco活化酶(RCA)活性的变化,分析MC-LR慢性暴露对水雍菜叶片光合生理的影响。【结果】MC-LR慢性暴露30 d后,与对照组相比,1μg/L MC-LR处理组水雍菜叶片的光合参数均无显著变化;10μg/L MC-LR处理组中,Rubisco及RCA活性显著降低,H 2O 2含量和非光化学淬灭系数(qN)显著上升,而叶绿素SPAD值、光系统Ⅱ(PSⅡ)最大量子产量(F_(v)/F_(m))和PSⅡ有效量子产量(ΦPSⅡ)无显著变化;30μg/L MC-LR处理组中,H 2O 2含量显著上升,而叶绿素SPAD值、F_(v)/F_(m)、ΦPSⅡ、光化学淬灭系数(qP)及Rubisco、RCA活性均显著降低。【结论】1μg/L MC-LR暴露对水雍菜叶片光合生理无显著影响;10μg/L MC-LR暴露下,叶片通过增加热耗散来保护光合机构,但MC-LR对光合酶活性产生抑制从而对叶片光合活性产生影响;30μg/L MC-LR暴露会抑制叶片光合系统对光能的转化效率、降低了叶片的光合酶活性,从而对水雍菜的光合能力产生不良影响。
【Objective】The chronic effects of microcystin-LR(MC-LR)at environmental relevant concentrations on photosynthesis of Ipomoea aquatica were studied to elucidate mechanism of low concentrations MC-LR exposure on growth of Ipomoea aquatica.【Method】After incubation for 30 days in nutrient solution containing MC-LR at different concentrations(0(CK),1,10,30μg/L),the changes in chlorophyll SPAD values,chlorophyll fluorescence parameters,H 2O 2 contents,Ribulose-1,5-bisphosphate carboxylase(Rubisco)and Rubisco activase(RCA)activities were analyzed to investigate the effects of MC-LR on photosynthesis of Ipomoea aquatica.【Result】After exposure to 1μg/L MC-LR for 30 days,there was no significant changes in photosynthetic parameters in leaves.After exposure to 10μg/L MC-LR activities of Rubisco and RCA decreased significantly,contents of H 2O 2 and qN increased significantly,while SPAD values of chlorophyll,F_(v)/F_(m)andΦPSⅡhad insignificant changes.After exposure to 30μg/L MC-LR,contents of H 2O 2 increased significantly,while SPAD values of chlorophyll,F_(v)/F_(m),ΦPSⅡand qP,and activities of Rubisco and RCA decreased significantly.【Conclusion】Exposure to 1μg/L MC-LR had no significant effect on photosynthetic physiological characteristics in leaves of Ipomoea aquatica.After exposure to 10μg/L MC-LR,leaves protected photosynthetic apparatus by increasing heat dissipation,but MC-LR inhibited activities of photosynthetic enzymes and affected photosynthetic activity of Ipomoea aquatica.Exposure to 30μg/L MC-LR inhibited transformation of light energy in photosynthetic system and decreased activities of photosynthetic enzymes,which had a negative effect on photosynthetic capacity of Ipomoea aquatica.
作者
陈国元
廖腾芳
李青松
CHEN Guoyuan;LIAO Tengfang;LI Qingsong(College of Environment Science and Engineering,Xiamen University of Technology,Xiamen,Fujian 361024,China)
出处
《西北农林科技大学学报（自然科学版）》
CSCD
北大核心
2021年第9期129-136,143,共9页
Journal of Northwest A&F University(Natural Science Edition)
基金
国家自然科学基金面上项目(51878582)
厦门理工学院科研攀登计划项目(XPDKT19026)。
关键词
微囊藻毒素
慢性暴露
水雍菜
光合系统
microcystin
chronic exposure
Ipomoea aquatica
photosynthetic system
