镉对梭鱼草叶片保护酶活性、光合及荧光特性的影响

doi:10.11686/cyxb2017463

摘要/Abstract

摘要： 为探究梭鱼草的耐镉能力和生理机制,以溶液培养法研究了不同浓度镉胁迫下梭鱼草叶片保护酶活性、叶绿素含量、光合气体交换参数及叶绿素荧光参数的变化。结果表明:梭鱼草叶片细胞膜透性随镉浓度的增加和胁迫时间的延长而增加。各处理组中叶片过氧化氢酶(CAT)活性基本处于相对稳定水平,超氧化物歧化酶(SOD)随镉浓度的增大呈下降趋势,过氧化物酶(POD)随镉浓度的增大和胁迫时间的延长呈先上升后下降的趋势。叶片叶绿素a(Chla)、叶绿素b(Chlb)含量、叶绿素总含量(ChlT)及叶绿素a/b(Chla/b)比值随着镉浓度的增加和胁迫时间的延长呈下降趋势,其中叶绿素a(Chla)较为敏感,在较短时间内即发生分解,是导致ChlT含量减少的主要原因。叶片净光合速率(P_n)、蒸腾速率(E)、气孔导度(G_s)及胞间CO₂浓度(C_i)均随镉浓度的增加和胁迫时间的延长呈下降趋势,饱和蒸气压亏缺(VPD)呈上升趋势,其中G_s降低是导致叶片P_n下降的主要因素。较高浓度(25,75 mg·L^-1)镉胁迫下梭鱼草叶片光合作用发生光抑制,使电子传递受阻,导致光系统Ⅱ(PSⅡ)反应中心的光能转化和利用效率下降,但其可通过增加非光化学途径的热耗散和激活未活化的反应中心来适应镉胁迫。

关键词: 梭鱼草, 镉胁迫, 保护酶活性, 光合色素, 光合特性, 叶绿素荧光特性

Abstract: Plants of Pontederia cordata were cultivated in 1/2 strength Hoagland’s nutrient solution containing cadmium at concentrations of 0, 5, 25 or 75 mg·L^-1, to research cadmium tolerance and its physiological mechanisms. Changes with Cd exposure in antioxidant enzyme activities, leaf chlorophyll contents, photosynthetic gas exchange and chlorophyll fluorescence parameters in P. cordata leaves were measured. It was found that plasma membrane permeability tended to increase with cadmium concentration and with exposure time. Changes in activities of superoxide dismutase (SOD), peroxidase (POD) and hydrogen peroxidase (CAT) differed. CAT activity was seldom influenced by Cd, whereas activities of SOD and POD were increased by Cd. Leaves showed an obvious decrease in chlorophyll a (Chla), chlorophyll b (Chlb), and total chlorophyll (ChlT) contents and in chlorophyll a/b (Chla/b) ratio with Cd exposure, and this effect was also more marked with increasing Cd concentration and exposure time. Chla was more sensitive to Cd, and Chla reduction was primarily responsible for the reduction in the ChlT content and for the reduced Chla/b ratio. A Cd-induced decrease in net photosynthetic rate (P_n) of P. cordata leaves was observed and was associated with a decline in stomatal conductance (G_s). Linked to this effect, transpiration rate (E), and intercellular CO₂ concentration (C_i) of leaves were also decreased by increased Cd concentration and exposure time, while vapor pressure deficit (VPD) was increased. Also, higher Cd concentrations (25, 75 mg·L^-1) resulted in photoinhibition, decreasing the photosynthetic electron transport system activity, and thus leading to a decline in energy conversion and utilization efficiency of photosystemⅡ (PSⅡ). However, P. cordata can adapt to Cd exposure by enhancing thermal dissipation and activating non-activated PSⅡ reaction centers.

Key words: Pontederia cordata, Cd stress, antioxidant enzyme activities, chlorophyll contents, photosynthetic characteristics, chlorophyll fluorescence characteristics

辛建攀, 李文明, 祁茜, 田如男. 镉对梭鱼草叶片保护酶活性、光合及荧光特性的影响[J]. 草业学报, 2018, 27(10): 23-34.

XIN Jian-pan, LI Wen-ming, QI Xi, TIAN Ru-nan. Effects of Cd on antixoidant enzyme activities, and leaf photosynthetic and fluorescence characteristics in Pontederia cordata[J]. Acta Prataculturae Sinica, 2018, 27(10): 23-34.

参考文献

[1] Gallego S M, Pena L B, Barcia R A, et al. Unravelling cadmium toxicity and tolerance in plants: insight into regulatory mechanisms. Environmental and Experimental Botany, 2012, 83(5): 33-46.
[2] Vig K, Megharaj M, Sethunathan N, et al. Bioavailability and toxicity of cadmium to microorganisms and their activities in soil: A review. Advances in Environmental Research, 2003, 8(1): 121-135.
[3] Dong Y Y, Sun Z, Yang Y, et al. Effects of cadmium of photosynthesis and Cd accumulation of Corchorus capsularis L. Journal of Nuclear Agricultural Sciences, 2017, 31(8): 1640-1646.
董袁媛, 孙竹, 杨洋, 等. 镉胁迫对黄麻光合作用及镉积累的影响. 核农学报, 2017, 31(8): 1640-1646.
[4] Xu X X, Dong Y Y, Deng Y L, et al. Effects of cadmium stress on growth and photosynthesis parameters of Sigesbeckia orientalis. Journal of Agro-Environmental Science, 2016, 35(9): 1672-1679.
徐小逊, 董袁媛, 邓玉兰, 等. 镉胁迫对豨莶生长及光合作用相关参数的影响. 农业环境科学学报, 2016, 35(9): 1672-1679.
[5] Xie P, Deng J, Zhang H, et al. Effects of cadmium on bioaccumulation and biochemical stress response in rice (Oryza sativa L.). Ecotoxicology and Environmental Safety, 2015, 122: 392-398.
[6] Singh S, Singh A, Bashri G, et al. Impact of Cd on celluar functions and its amelioration by phytohormones: An overveiw on regulatory network. Plant Growth Regulation, 2016, 80(3): 253-263.
[7] Zemanová V, Pavlík M, Pavlíková D, et al. Responses to Cd stress in two Noccaea species (Noccaea praecox and Noccaea caerulescens) originating from two contaminated sites in Mežica, Slovenia and Redlschlag, Austria. Archives of Environmental Contamination and Toxicology, 2016, 70(3): 464-474.
[8] Garbisch E W, Mclninch S.Seed information for wetland plant species of the Northeast United States. Restoration and Management Notes, 1992, 10(1): 85-86.
[9] Gettys L A, Wofford D S.Inheritance of flower color in pickerelweed (Pontederia cordata L.). Journal of Heredity, 2007, 98(6): 629-632.
[10] Olguín E J, Sánchez-Galván G, González-Portela R E, et al. Constructed wetland mesocosms for treatment of diluted sugarcane molasses stillage from ethanol production using Pontederia sagittata. Water Research, 2008, 42(14): 3659-3666.
[11] Zhang Y, Xu H, Chen H, et al. Diversity of wetland plants used traditionally in China: A literature review. Journal of Ethnobiology and Ethnomedicine, 2014, 10: 72.
[12] Gettys L A, Dumroese R K.Optimum storage and germination conditions for seeds of pickerelweed (Pontederia cordata L.) from Florida. Native Plants Journal, 2009, 10(1): 4-12.
[13] Gettys L A, Wofford D S.Genetic control of floral morph in tristylous pickerelweed (Pontederia cordata). Journal of Heredity, 2008, 99(5): 558-563.
[14] Yu H B, Yang Z J, Xiao R L, et al. Research of ditch interception of nitrogen and phosphorus of Pontederia cordata. Research of Agricultural Modernization, 2012, 33(4): 508-512.
余红兵, 杨知建, 肖润林, 等. 梭鱼草(Pontederia cordata)拦截沟渠中氮、磷的效果研究. 农业现代化研究, 2012, 33(4): 508-512.
[15] Lu X M, Lu P Z, Chen J J.Effects of planting densities on water quality improvements and Pontederia cordata’s physiology. International Journal of Phytoremediation, 2014, 16(5): 469-481.
[16] Wei J Y, Chen Z H.Removal of heavy metal elements and nutrients by Pontederia cordata and Phragmites australis constructed wetlands. Chinese Journal of Applied and Enviromental Biology, 2013, 19(1): 179-183.
韦菊阳, 陈章和. 梭鱼草和芦苇人工湿地对重金属和营养的去除率比较. 应用与环境生物学报, 2013, 19(1): 179-183.
[17] Zhang X Z.Determination of chlorophyll content——sopping extraction method with mixing solution of alcohol and acetone. Journal of Liaoning Agricultural Science, 1986, (3): 26-28.
张宪政. 植物叶绿素含量测定——丙酮乙醇混合液法. 辽宁农业科学, 1986, (3): 26-28.
[18] Hao Z B, Cang J, Xu Z.Plant physiology experiment. Harbin: Harbin Institute of Technology Pressing House, 2004: 101-104.
郝再彬, 苍晶, 徐仲.植物生理实验. 哈尔滨: 哈尔滨工业大学出版社, 2004: 101-104.
[19] Li H S, Sun Q, Zhao S J, et al.Principles and techniques of plant physiology and biochemistry experiment. Beijing: Higher Education Press House, 2000: 164-169.
李合生, 孙群, 赵世杰, 等. 植物生理生化实验原理和技术. 北京: 高等教育出版社, 2000: 164-169.
[20] Qu D Y, Zhang L G, Gu W R, et al. Effect of chitosan on root growth and leaf photosynthesis of maize seedlings under cadmium stress. Chinese Journal of Ecology, 2017, 36(5): 1300-1309.
曲丹阳, 张立国, 顾万荣, 等. 壳聚糖对镉胁迫下玉米幼苗根系生长及叶片光合的影响. 生态学杂志, 2017, 36(5): 1300-1309.
[21] Muñoz N, González C, Molina A, et al. Cadmium-induced early changes in ${O_{2}}^{-·}$, H₂O₂ and antioxidative enzymes in soybean (Glycine max L.)leaves. Plant Growth Regulation, 2008, 56(2): 159-166
[22] Yang W D, Chen Y T.Membrane leakage and antioxidant enzyme activities in roots and leaves of Salix matsudana with cadmium stress. Acta Botanical Boreali-Occidentalia Sinica, 2008, 28(11): 2263-2269.
杨卫东, 陈益泰. 镉胁迫对旱柳细胞膜透性和抗氧化酶活性的影响. 西北植物学报, 2008, 28(11): 2263-2269.
[23] Pereira G J G, Molina S M G, Lea P J, et al. Activity of antioxidant enzymes in response to cadmium in Crotalaria juncea. Plant and Soil, 2002, 39(1): 123-132.
[24] YuanY, Ke X, Chen F, et al. Decrease in catalase activity of Folsomia canadia fed a Bt rice diet. Environment Pollution, 2011, 159(12): 3714-3720.
[25] Israr M, Sahi S V, Jain J.Cadmium accumulation and antioixdative responses in the Sesbania drummondii callus. Archives of Evironmental Contamination and Toxicology, 2006, 50(1): 121-127.
[26] Zhang S, Zhang H, Qin R, et al. Cadmium induction of lipid peroxidation and effects on root tip cells and antixoidant enzyme activities in Vicia faba L. Ecotoxicology, 2009, 18(7): 814-823.
[27] Tian Z G, Wang F.Growth and physiological responses of Tagetes cultivars to cadmium stress. Acta Botanical Boreali-Occidentalia Sinica, 2013, 33(10): 2057-2064.
田治国, 王飞. 不同品种万寿菊对镉胁迫的生长和生理响应. 西北植物学报, 2013, 33(10): 2057-2064.
[28] Zhu H X, Zhou X D, Ge C L, et al. Effect of combined pollution on cell membrane penetrability and protection enzyme activity of rice seeding. Ecology and Environmen, 2008, 17(3): 999-1003.
朱红霞, 周晓冬, 葛才林, 等. 复合污染对水稻幼苗细胞膜透性及保护酶活性的影响. 生态环境, 2008, 17(3): 999-1003.
[29] He L X, Huang Y X, Huang C Y, et al. Physiological responses of Chamaecrista rotundifolia to cadmium exposure. Acta Prataculturase Sinica, 2016, 25(2): 198-204.
何梨香, 黄运湘, 黄楚瑜, 等. 圆叶决明对镉胁迫的生理响应. 草业学报, 2016, 25(2): 198-204.
[30] Feng S J, Yang T X, Zhang Y J, et al. Effects of cadmium on photosynthetic gas exchange and chlorophyll fluorescence of two species of poplar. Journal of Agro-Environmental Science, 2013, 32(3): 539-547.
冯世净, 杨图袭, 张艳军, 等. 镉胁迫对杨树光合特性的影响. 农业环境科学学报, 2013, 32(3): 539-547.
[31] Ran X, Liu R, Bai F, et al. Assessment of growth rate, chlorophyll a fluorescence, lipid peroxidation and antioxidant enzyme activity in Aphanizomenon flos-aquae, Pediastrum simplex and Synedra acus exposed to cadmium. Ecotoxicology, 2015, 24(2): 468-477.
[32] Horváth G, Droppa M, Oravecz À, et al. Formation of the photosynthetic apparatus during greening of cadmium-poisoned barley leaves. Planta, 1996, 199(2): 238-243.
[33] Shukla U C, Singh J, Joshi P C, et al. Effect of bioaccumulation of cadmium on biomass productivity, essential trace elements, chlorophyll biosynthesis, and macromolecules of wheat seedlings. Biological Trace Elements Research, 2003, 92(3): 257-273.
[34] Wahid A, Ghani A, Javed F.Effect of cadmium on photosynthesis, nutrition and growth of mungbean. Agronomy for Sustainable Development, 2008, 28(2): 273-280.
[35] Ebrahim M K H. Tolerance responses of two cotton cultivars exposed to ultraviolet-A(336 nm): Photosynthetic performance and some chemical constitutents. Agrchimica, 2004, 48(5/6): 177-191.
[36] Xue Z C, Gao H Y, Zhang L T.Effects of cadmium on growth, photosynthesis rate, and chlorphyll content in leaves of soybean seedlings. Biologia Plantarum, 2013, 57(3): 587-590.
[37] Franco E, Alessandrelli S, Masojídek J, et al. Modulation of D₁ protein turnover under cadmium and heat stresses monitored by [35S] methionine incorporation. Plant Science, 1999, 144(2): 53-61.
[38] Lagriffoul A, Mocquot B, Mench M, et al. Cadmium toxicity effects on growth, mineral and chlorophyll contents, and activities of stress related enzymes in young maize plants(Zea mays L.). Plant and Soil, 1998, 200(2): 241-250.
[39] Han S H, Lee J C, Oh C Y, et al. Alleviation of Cd toxicity by composted sewage sludge in Cd-treated schmidt birch (Betula schmidtii) seedings. Chemosphere, 2006, 65(4): 541-546.
[40] Ci D, Jiang D, Wollenweber B, et al. Cadmium stress in wheat seedlings: growth, cadmium accumulation and photosynthesis. Acta Physiologiae Plantarum, 2010, 32(2): 365-373.
[41] Tanyolaç D, Ekmekçi Y, Ünalan ş.Changes in photochemical and antioxidant enzymes activities in maize (Zea mays L.) leaves exposed to excess copper. Chemosphere, 2007, 67(1): 89-98.
[42] Li M, Zhang L J, Tao L, et al. Ecophysiological responses of Jussiaea rapens to cadmium exposure. Aquatic Botany, 2008, 88(4): 347-352.
[43] Perfus-Barbeoch L, Leonhardt N, Vavasseur A, et al. Heavy metal toxicity: Cadmium permeates through calcium channels and disturbs the plant water status.The Plant Journal, 2002, 32(4): 539-548.
[44] Sun J, Hu H, Li Y, et al. Effects and mechanisms of acid rain on plant chloroplast ATP synthase. Environmental Science and Pollution Research, 2016, 23(18): 18296-18306.
[45] Gouia H, Ghorbal M H, Meyer C.Effects of cadmium on activity of nitrate reductase and on other enzymes of the nitrate assimilation pathway in bean. Plant Physiology and Biochemistry, 2000, 38(7/8): 629-638.
[46] Zhang J P, Chen J, Hu Y H, et al. Effects of cadmium stress on photosynthetic function of leaves of Lemna minor L. Journal of Agro-Environmental Science, 2007, 26(6): 2027-2032.
张建平, 陈娟, 胡一鸿, 等. 镉胁迫对浮萍叶片光合功能的影响. 农业环境科学学报, 2007, 26(6): 2027-2032.
[47] Von Heerden P D R, Strasser R J, Krüger G H J. Reduction of dark chilling stress in N₂-fixing soybean by nitrate as indicated by chlorophyll a fluorescence kinetics. Physiological Plantarum, 2004, 121(2): 239-249.
[48] Ali N A, Dewez D, Didur O, et al. Inhibition of photosystem Ⅱ photochemistry by Cr is caused by the alteration of both D₁ protein and oxygen evolving complex. Photosynthesis Research, 2006, 89(2): 81-87.
[49] Kreslavski V D, Carpentier R, Klimov V V,et al. Molecular mechanisms of stress resistance of the photosynthetic apparatus. Biochemistry (Moscow) Supplement Series A: Membrane and Cell Biology, 2007, 1(3): 185-205.