摘要
【目的】探讨氮缺乏及氮补充对铜绿微囊藻细胞密度、光合色素和叶绿素荧光参数的影响,为揭示水华暴发机制及其影响因素提供参考依据。【方法】使用BG-11全培养基(对照组)和无氮BG-11培养基(处理组)分别培养铜绿微囊藻7 d后,再转移至BG-11全培养基中继续培养,于不同培养时期测定铜绿微囊藻密度、光合色素含量及叶绿素荧光参数等指标,观察其变化规律。【结果】氮饥饿处理铜绿微囊藻7 d后,处理组藻密度(2.10×10^7 cell/mL)极显著低于对照组(3.11×10^7 cell/mL)(P<0.01,下同),氮补充144 h后,处理组的藻细胞密度为3.35×10^7 cell/mL,仍极显著低于对照组(4.32×10^7 cell/mL);氮缺乏会极显著或显著(P<0.05)抑制铜绿微囊藻叶绿素a、类胡萝卜素和藻胆蛋白的合成,但抑制作用随氮补充时间的延长而降低;氮饥饿处理后,处理组铜绿微囊藻可溶性蛋白含量较对照组减少64.50μg/L,氮补充144 h后二者相差44.10μg/L,但差异不显著(P>0.05);氮饥饿处理后再恢复氮补充对铜绿微囊藻光合作用速率有明显促进作用,尤其是Fv/Fm在氮补充12 h后开始逐渐提高,至144 h后极显著高于对照组。【结论】氮缺乏会抑制铜绿微囊藻的分裂增殖及正常代谢过程,但这种抑制作用随着氮补充时间的延长而减弱;在氮补充后,铜绿微囊藻叶绿素a、类胡萝卜素和藻胆蛋白的含量虽然呈升高趋势,但很难恢复至正常水平。Fv/Fm等叶绿素荧光参数对氮营养盐缺乏后再补充具有良好的响应作用,可作为营养盐监测的指示指标。
【Objective】In the present study,effects of nitrogen recovery on cell density,photosynthetic pigments content and chlorophyll fluorescence parameters of Microcystis aeruginosa after nitrogen starved were studied to provide reference for the mechanism of Microcysis blooms outbreaks and its influencing factors.【Method】Using BG-11 medium(control group)and nitrogen-free BG-11 medium(treatment group)cultured M.aeruginosa for 7 d,then transferred to BG-11 medium,measured the cell density,photosynthetic pigments content and chlorophyll fluorescence parameters in different times.【Result】After nitrogen starved 7 d,the cell density of M.aeruginosa in the treatment group(2.10×10^7 cell/mL)was extremely lower than that in the control group(3.11×10^7 cell/mL)(P<0.01,the same below),after nitrogen recovered 144 h,its cell density of treatment groups was 3.35×10^7 cell/mL,still extremely lower than the control groups(4.32×10^7 cell/mL).Nitrogen starvation could inhibit the synthetize of chl-a,carotenoid and phycobiliprotein,the difference reduced with the time of nitrogen recovery.The soluble protein content was 64.50μg/L lower than that in the control groups because of nitrogen starvation,it was still 44.10μg/L lower than that after recovery,but the difference was not significant(P>0.05).The recovery of nitrogen could accelerate the photosynthesis rate of M.aeruginosa significantly,especially the Fv/Fm responded to nitrogen recovery in 12 h obviously,and was extremely higher than control group after 144 h.【Conclusion】Nitrogen starved can inhibit the cleavage,proliferation and metabolize,however,the inhibition reduces with the nitrogen recovery time.After nitrogen recovery,the contents of chl-a,carotenoid and phycobiliprotein increase,but cannot reach the normal levels.Fv/Fm respond to the nutrient deficiency and recovery sensitively,soit can be used as indicator of the nutrient monitors.
作者
张达娟
张树林
王泽斌
李鹏英
ZHANG Da-juan;ZHANG Shu-lin;WANG Ze-bin;LI Peng-ying(Tianjin Key Laboratory of Aqua-Ecology and Aquaculture/College of Fisheries,Tianjin Agricultural University,Tianjin 300384,China)
出处
《南方农业学报》
CAS
CSCD
北大核心
2019年第11期2592-2598,共7页
Journal of Southern Agriculture
基金
天津现代产业技术体系建设项目(ITTFRS2017015)
天津市高等学校创新团队培养计划项目(TD13-5089)
关键词
铜绿微囊藻
氮饥饿
氮补充
光合色素
可溶性蛋白
叶绿素荧光参数
Microcystis aeruginosa
nitrogen starvation
nitrogen recovery
pigment
soluble protein
chlorophyll fluorescence parameters
