铅胁迫对禾本科牧草生长、生理及Pb<sup>2+</sup>富集转运的影响

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李慧芳, 王瑜, 袁庆华, 赵桂琴. 铅胁迫对禾本科牧草生长、生理及Pb²⁺富集转运的影响 . 草业学报, 2015,24(9): 163-172
LI Hui-Fang, WANG Yu, YUAN Qing-Hua, ZHAO Gui-Qin. Effects of lead stress on growth, physiology, and lead ion accumulation and transportation in gramineous forages. Acta Prataculturae Sinica,2015,24(9): 163-172 复制到剪切板

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铅胁迫对禾本科牧草生长、生理及Pb²⁺富集转运的影响

李慧芳^1,², 王瑜¹, 袁庆华^1,^*, 赵桂琴²

1.中国农业科学院北京畜牧兽医研究所,北京 100193

2.甘肃农业大学草业学院,甘肃兰州 730070

*通讯作者Corresponding author. E-mail:yuanqinghua@hotmail.com

作者简介:李慧芳(1987-),女,山西忻州人,在读硕士。 E-mail:lhf523-dxxz@163.com

收稿日期: 2014-07-03

基金项目:十二五国家科技支撑计划课题(2011BAD17B01),国家牧草产业体系(岗位专家)项目(CARS-35)和中国农业科学院北京畜牧兽医研究所基本科研业务费项目(2014ywf-zd-2)资助

摘要

采用苗期盆栽试验,对14份禾本科牧草种质材料进行不同浓度(0,10,50,100,200,300 mg/kg)铅(Pb)胁迫处理,通过对株高、分蘖数、地上/地下生物量、脯氨酸含量、抗氧化酶(SOD、POD、CAT)活性、地上部与根中Pb²⁺含量等指标的测定与分析,探究Pb胁迫对禾草生长生理以及Pb²⁺富集转运的影响。结果表明,随着Pb浓度的增加,14份材料的株高、分蘖数、地上生物量均呈先上升后下降的趋势,地下生物量则逐渐降低,通过综合评价,来自土耳其的长穗冰草G₅具有较强的耐Pb性。随着Pb浓度的增加,地上部与根中Pb²⁺含量逐渐升高,富集系数逐渐降低,转移系数逐渐降低(披碱草G₇与G₈除外),根中Pb²⁺含量显著高于地上部,为Pb²⁺的主要富集器官,披碱草地上部Pb²⁺含量高于其他材料,具有较强的Pb富集转运能力。7份材料的生理指标测定结果表明,随着Pb浓度的增加,7份材料的脯氨酸含量逐渐上升,CAT活性逐渐下降,POD和SOD活性则呈先上升后下降的趋势。

关键词: 禾本科牧草; 苗期; 铅胁迫; 生长和生理; 富集转运

Effects of lead stress on growth, physiology, and lead ion accumulation and transportation in gramineous forages

LI Hui-Fang^1,², WANG Yu¹, YUAN Qing-Hua^1,^*, ZHAO Gui-Qin²

1.Institute of Animal Science of CAAS, Beijing 100193, China

2.College of Grassland Science, Gansu Agricultural University, Lanzhou 730070, China

Abstract

Fourteen gramineous forages were stressed by different lead treatments (0, 10, 50, 100, 200, 300 mg/kg) at the seedling stage in pots. By measurement of plant height, tiller number, shoot and root biomass, antioxidant enzyme activities and shoot and root lead ion content, the effects of lead stress on growth, physiology, accumulation and transportation were analyzed. At low levels of lead exposure, plant height, tiller number and shoot biomass were generally increased, then reduced gradually with increasing lead exposure. Agropyron elongatum G₅ from Turkey was found to have a high lead tolerance. With increasing lead exposure, lead ion content in roots and shoots increased gradually, while the bio-concentration factor and transfer factor decreased gradually except for Elymus dahuricus G₇ and G₈. The content of lead ions in roots was significantly higher than that in shoots, from which we concluded that the root was the main organ by which Poaceous forages accumulate lead ions. The content of lead ions in shoots of E. dahuricus G₇ and G₈ were higher than in other germplasm, indicating a high capacity for lead accumulation and transportation. From physiological analysis of seven evaluated varieties, it was found that with increased lead exposure, proline content increased gradually, and catalase (CAT) activity decreased gradually, while peroxidase (POD) and superoxide dismutase (SOD) were elevated at low levels of exposure, but decreased at higher levels of exposure.

Keyword: gramineous forages; seedling stage; lead stress; growth and physiology; accumulation and transportation

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铅(Pb)是最严重的环境重金属污染物之一^[1]。Pb广泛存在于自然界, 易被土壤吸附, 不易被生物降解。Pb在植物根、茎、叶及籽粒中的累积, 不仅严重影响植物的生长发育、降低产量和质量^[2], 并通过生物链富集而对人类健康造成严重的威胁, 成为环境治理中越来越突出的问题。

重金属胁迫导致植物体内活性氧的增加是其毒害植物的重要机制之一。活性氧能够快速地与DNA、脂类、蛋白质等反应从而造成细胞损伤^{[3, 4]}。正常情况下, 植物体内的活性氧物质主要通过抗氧化剂和抗氧化酶两者协同清除; 在逆境胁迫下, 植物体内的活性氧数量剧增, 植物的抗氧化酶活性迅速升高, 对清除活性氧起到重要的应激反应, 成为环境胁迫下应激反应的重要检测指标^[5]。已有研究表明, Pb胁迫会导致羽扇豆(Lupinus luteus cv. Ventus)与豌豆(Pisum sativum)根部、水稻(Oryza sativa)植株、玉米(Zea mays)愈伤组织等活性氧的增加与抗氧化酶活性的增强^[6]。另有研究表明, Pb胁迫会导致假俭草(Eremochloa ophiuroides)、结缕草(Zoysia japonica)、多年生黑麦草(Lolium perenne)等植物体内脯氨酸含量的升高^{[7, 8]}。脯氨酸的积累可以调节细胞内的渗透势, 维持水分平衡, 保护细胞内重要代谢活动所需的酶类活性, 为植物适应逆境胁迫的基本特征之一^[9]。

我国拥有丰富的草种质资源, 但这些资源并没有得到充分的利用, 造成了资源的严重浪费。禾本科牧草适应性强, 耐刈耐牧耐栽培, 是优良的水土保持、防风固沙的绿化植物, 在草地生态系统中具有重要作用。钱海燕等^[10]研究发现黑麦草对Cu、Zn污染土壤有一定的耐性及修复作用; Tamas和Kovacs^[11]认为早熟禾(Poa spp.)对Pb的吸收富集能力较强。本研究选取多年生黑麦草、老芒麦(Elymus sibiricus)、鹅观草(Roegneria kamoji)、披碱草(Elymus dahuricus)、高羊茅(Festuca elata)、长穗冰草(Agropyron elongatum)和鸭茅(Dactylis glomerata)等禾草作为试验材料, 通过对其在Pb胁迫下的形态指标(株高、分蘖数、地上/地下生物量)与生理指

标(脯氨酸含量、抗氧化酶活性)的测定与分析, 筛选受损程度较轻及耐Pb性较强的材料, 并掌握Pb胁迫下禾草的生理响应机制, 另外, 通过对Pb²⁺在禾草植株内富集转运的研究, 筛选Pb富集能力较强的禾草, 为Pb污染土壤植物修复中禾草的选择提供依据。

1 材料与方法

1.1 试验材料

供试14份禾草种质材料由中国农业科学院北京畜牧兽医研究所提供, 材料名称及来源见表1。供试土由壤土、草炭土和营养土按1:1:1均匀混合, 其理化性质如下:pH 6.5, 全氮2.8 g/kg, 全钾19 g/kg, 全磷6.7 g/kg, Pb含量3.37 mg/kg。

1.2 试验方法

1.2.1 材料的培养与处理试验于2013年3-8月在中国农业科学院北京畜牧兽医研究所廊坊试验基地温室中进行。将壤土、草炭土和营养土(1:1:1)均匀混合后装入无孔塑料花盆(高20 cm, 底径15 cm, 口

表1 试验材料及来源 Table 1 Materials and their resources

径20 cm), 每盆装土1.5 kg。装土完成后, 在盆中点入已发芽试验材料种子, 每材料点播3盆, 每盆25株, 待长出两片真叶后进行间苗, 每盆留苗15株。

间苗7 d后进行Pb处理, 将硝酸铅Pb(NO₃)₂配制成一定浓度的溶液施入盆中。Pb处理共设置6个浓度梯度, 0, 10, 50, 100, 200, 300 mg/kg(风干土重), 以纯Pb计, 分别以CK、Pb₁₀、Pb₅₀、Pb₁₀₀、Pb₂₀₀和Pb₃₀₀表示, 每处理3个重复。Pb胁迫期间进行正常管理, 定期定量浇水, 以保持土壤含水量为最大持水量的70%。

Pb处理30 d后进行指标测定。

1.2.2 生长指标的测定株高:用直尺测量植株地上部的垂直高度, 以每盆中15株苗的平均值作为株高, 精确到0.01 cm。相对株高=Pb处理植株的株高/对照植株的株高。

分蘖数:测定植株的分蘖, 以每盆中15株苗的平均值作为分蘖数, 精确到1个。相对分蘖数=Pb²⁺处理植株的分蘖数/对照植株的分蘖数。

地上与地下生物量:自来水冲洗下轻柔地将植株根部从土壤中分离并冲洗干净, 蒸馏水冲洗干净后用剪刀将植株地上部与地下部分开, 用纸包好后放入烘箱, 105℃杀青30 min, 之后70℃烘干至恒重(12 h)后进行称量。每盆15株苗地上部的总干重为地上生物量, 地下部的总干重为地下生物量, 精确到0.001 g。

1.2.3 生理指标的测定分别从每个种中选择1份材料, 共7份材料(G₁、G₃、G₆、G₇、G₁₀、G₁₂与G₁₄)进行游离脯氨酸(Pro)含量、过氧化氢酶(CAT)活性、过氧化物酶(POD)活性、超氧化物歧化酶(SOD)活性等生理指标的测定。Pro含量的测定参照李合生^[12]的酸性茚三酮比色法, CAT活性的测定参照Dhindsa等^[13]的紫外吸收法, POD活性的测定参照刘祖祺和张石城^[14]的愈创木酚法, SOD活性的测定参照Cao等^[15]的NBT光还原法。

1.2.4 地上部与根部Pb²⁺含量的测定分别称取烘干磨细过0.5 mm筛的植株地上部与根部样品1.0 g于25 mL试管中, 加入硝化液(5 mL浓硝酸、1 mL 60% 三氯乙酸、0.5 mL浓硫酸), 90℃水浴硝解120 min, 冷却后过滤, 取50 μ L滤液用超纯水定容至250 mL。利用美国热电公司的电感耦合等离子体发射光谱仪(ICP-MS)对Pb²⁺含量进行测定。

生物富集系数(bioconcentration factor, BCF)=植物地上或根系Pb²⁺积累浓度/土壤中Pb²⁺浓度^[16]; 转运系数(translocation factor, TF)=地上部Pb²⁺积累浓度/根中Pb²⁺积累浓度^[17]; 积累量=植物地上或根系Pb²⁺积累浓度× 植物地上或根系生物量。

1.3 耐Pb性综合评价

利用株高、分蘖数、地上与地下生物量等生长指标, 采用标准差系数赋予权重法^[18]对14份禾草进行耐铅性综合评价。

1.4 数据处理

利用Microsoft Excel 2007软件进行数据统计分析和作图, 采用SPSS 16.0软件的Duncan检验进行方差分析。

2 结果与分析

2.1 Pb胁迫对禾草株高和分蘖数的影响

如表2所示, 随Pb处理浓度的升高, 14份材料的相对株高呈现先上升后下降的趋势。当Pb浓度为10, 50, 100 mg/kg时, 分别有12, 13和10份种质的相对株高高于对照, 且最大增幅分别为15.2%, 16.7%和19.6%, 说明低浓度Pb对禾草的生长有促进作用。当Pb浓度增至300 mg/kg时, 除G₂外, 其余各材料的株高明显低于对照, 其中下降幅度最大的材料是来自河北木兰围场的鹅观草G₅, 降幅为29.9%。

表2 Pb胁迫对相对株高和相对分蘖数的影响 Table 2 The effect of lead stress on relative plant height and relative tillering number

在相同Pb浓度下, 14份材料的相对分蘖数存在显著差异(P< 0.05)。当Pb浓度为10 mg/kg时, 供试材料相对分蘖数均显著高于对照, 说明该浓度下, Pb对分蘖有促进作用。但随着Pb浓度的增加, 相对分蘖数下降。在Pb浓度为300 mg/kg时, 14份材料相对分蘖数均低于对照, 其中降幅最大的是来自河北赤城的老芒麦G₄, 与对照相比下降了67.6%。

2.2 Pb胁迫对禾草地上和地下生物量的影响

当Pb处理浓度为10 mg/kg时, 有9份材料的相对地上生物量高于对照(表3)。随着Pb浓度的增加, 各材料相对地上生物量逐渐降低, 当Pb浓度增至300 mg/kg时, 14份材料相对地上生物量与对照相比下降幅度为10.7%~45.7%, 其中来自荷兰的鸭茅G₁₄降幅最小, 来自江苏丰县的披碱草G₈降幅最大。

表3 Pb胁迫对相对地上和地下生物量的影响 Table 3 The effect of lead stress on relative root and shoot biomass

从表3可以看出, Pb浓度越大, 14份材料相对地下生物量越低。当Pb浓度为100 mg/kg时, 除G₈外, 其他材料的相对地下生物量均呈明显下降趋势, 各材料间相对地上生物量存在显著差异(P< 0.05)。当Pb浓度为300 mg/kg时, 相对地下生物量降幅最大的是来自丹麦的多年生黑麦草G₂, 其次是来自加拿大的长穗冰草G₁₁, 分别比对照下降了61.0%和57.7%。

2.3 14份禾草耐Pb性综合评价

利用标准差系数赋予权重法对14份禾草的耐Pb性进行排序(表4), 结果发现不同种之间以及同一种的不同来源地之间均存在差异, 14份禾草的耐Pb性不存在种特异性。耐Pb性由强到弱排序为:G₁₂> G₉> G₆> G₃> G₁₀> G₁₃> G₁> G₈> G₄> G₁₁> G₇> G₁₄> G₂> G₅。来自于土耳其的长穗冰草G₁₂耐Pb性最强, 来自于河北的鹅观草G₅耐Pb性最弱。

表4 14份禾草的耐铅系数、隶属函数值及综合评价D值 Table 4 The lead tolerance coefficient, subordination value and D value of comprehensive evaluation of fourteen forage grasses

2.4 Pb胁迫对脯氨酸含量的影响

由图1可知, 当Pb处理浓度为0时, 鹅观草(G₆)、高羊茅(G₁₀)、长穗冰草(G₁₂)、鸭茅(G₁₄)叶片中脯氨酸含量均小于1 μ g/g, 多年生黑麦草(G₁)、老芒麦(G₃)、披碱草(G₇)均大于1 μ g/g, 这可能是由于材料自身的差异造成的。7份材料叶片中脯氨酸含量均随着Pb浓度的增加而升高, 当Pb浓度为300 mg/kg时, 各材料脯氨酸含量与对照相比显著增加, 鸭茅(G₁₄)的增幅最大, 较对照增长78.2倍, 多年生黑麦草(G₁)增幅最小, 较对照增长28.3%。

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	图1 Pb胁迫对禾草脯氨酸含量的影响Fig.1 The effects of lead stress on proline content of forage grasses

2.5 Pb胁迫对CAT活性的影响

由图2可知, 随着Pb处理浓度的增加, 各材料叶片中CAT活性呈现下降趋势。当Pb浓度为50 mg/kg时, 多年生黑麦草(G₁)、高羊茅(G₁₀)、长穗冰草(G₁₂)、鸭茅(G₁₄)等4份材料的CAT活性较对照显著下降(P< 0.05), 降幅均大于50%。当Pb浓度为300 mg/kg时, 7份材料CAT活性较对照均显著下降(P< 0.05), 降幅为69.9%~88.8%, 多年生黑麦草(G₁)的降幅最大(88.8%), 鹅观草(G₆)的降幅最小(69.9%)。

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	图2 Pb胁迫对禾草CAT活性的影响Fig.2 The effects of lead stress on CAT activity of forage grasses

2.6 Pb胁迫对POD活性的影响

由图3可以看出, 随着Pb处理浓度的增加, 7份材料的POD活性大体上都呈现出先上升后下降的趋势。其中, 多年生黑麦草(G₁)、老芒麦(G₃)、鹅观草(G₆)、长穗冰草(G₁₂)和鸭茅(G₁₄)等5份材料的POD活性在Pb浓度为100 mg/kg时达到峰值, 披碱草(G₇)与高羊茅(G₁₀)则在Pb浓度为10 mg/kg时达到峰值。当Pb浓度为300 mg/kg时, 披碱草(G₇)与长穗冰草(G₁₂)的POD活性仍旧高于对照, 分别高于对照10.0%与3.9%, 其余5份材料的POD活性均低于对照, 与对照相比, 5份材料POD活性的降幅为0~15.2%, 多年生黑麦草(G₁)降幅最大(15.2%)。

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	图3 Pb胁迫对禾草POD活性的影响Fig.3 The effects of lead stress on POD activity of forage grasses

2.7 Pb胁迫对SOD活性的影响

由图4可以看出, 随着Pb处理浓度的升高, 7份材料叶片中SOD活性呈现先上升后下降的趋势。多年生黑麦草(G₁)、老芒麦(G₃)、披碱草(G₇)、高羊茅(G₁₀)和鸭茅(G₁₄)等5份材料在Pb浓度为50 mg/kg时达到峰值, 其增幅为对照的24.6%~108.9%, 披碱草(G₇)的增幅最高(108.9%)。鹅观草(G₆)和长穗冰草(G₁₂)在Pb浓度为100 mg/kg时达到峰值, 与对照相比, 其增幅分别为95.7%和46.1%, 均显著高于对照(P< 0.05)。当Pb浓度为300 mg/kg时, 7份材料的SOD活性仍均高于对照, 高出比例为1.7%(鸭茅)~49.6%(披碱草)。

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	图4 Pb胁迫对禾草SOD活性的影响Fig.4 The effects of lead stress on SOD activity of forage grasses

2.8 不同Pb处理浓度下14份供试材料的富集系数和转移系数的变化

14份禾本科牧草体内Pb²⁺含量随着Pb处理浓度的升高而增加(表5)。在相同Pb处理浓度下, 除披碱草G₇和G₈外, 其余材料根部Pb²⁺含量明显高于叶片, 说明禾本科牧草吸收Pb²⁺主要集中在根部, 很少可以运输到地上部。各材料根与地上部富集系数(BCF)随着Pb处理浓度的升高而显著下降(P< 0.05), 根下降的幅度更大。

各禾本科牧草的转移系数(TF)由材料不同而表现出不同的趋势。披碱草(G₇与G₈)的TF随着Pb处理浓度的升高表现出先降低后升高再降低的趋势, 当Pb处理浓度为200 mg/kg时, G₇与G₈的TF达到最大值且均大于1, 分别为1.04与1.02; 其他材料的TF则随着Pb处理浓度的升高而逐渐降低, 且TF均小于1。

表5 Pb胁迫对禾本科牧草根和地上部中Pb²⁺含量的分布 Table 5 The effect of lead stress on lead ions content in root and shoot of forage grasses

序号 NO.	Pb处理 Pb treatment	Pb²⁺含量 Pb²⁺ content (mg/kg)		生物富集系数Bio-concentration factor (BCF)		转移系数 Translocation factor (TF)
序号 NO.	Pb处理 Pb treatment	地上部Shoot	根Root	地上部Shoot	根Root	转移系数 Translocation factor (TF)
G₁	Pb₁₀	17.05± 1.21a	33.56± 3.26a	1.71± 0.12a	3.36± 0.33a	0.51± 0.04a
	Pb₅₀	20.30± 1.46b	40.28± 5.07a	0.41± 0.03b	0.81± 0.10b	0.50± 0.03a
	Pb₁₀₀	24.35± 2.03c	52.65± 4.93b	0.24± 0.02c	0.53± 0.05c	0.46± 0.04b
	Pb₂₀₀	26.05± 1.09d	66.96± 11.02c	0.13± 0.01d	0.33± 0.06d	0.39± 0.01c
	Pb₃₀₀	36.15± 1.37e	105.32± 13.01d	0.12± 0.00d	0.35± 0.04d	0.34± 0.01d
G₂	Pb₁₀	11.75± 1.03a	25.24± 5.29a	1.18± 0.10a	2.52± 0.53a	0.47± 0.01a
	Pb₅₀	15.75± 1.05b	38.86± 1.08b	0.32± 0.02b	0.78± 0.02b	0.41± 0.09b
	Pb₁₀₀	16.95± 1.10c	47.77± 7.45c	0.17± 0.01c	0.48± 0.07c	0.35± 0.01c
	Pb₂₀₀	21.40± 1.13d	53.43± 3.73d	0.11± 0.01d	0.27± 0.02d	0.40± 0.03b
	Pb₃₀₀	23.60± 1.11e	66.35± 9.10e	0.08± 0.00d	0.22± 0.03e	0.36± 0.01c
G₃	Pb₁₀	17.55± 0.98a	27.37± 2.66a	1.76± 0.10a	2.74± 0.27a	0.64± 0.04a
	Pb₅₀	18.40± 1.54b	56.64± 8.94b	0.37± 0.03b	1.13± 0.18b	0.32± 0.02b
	Pb₁₀₀	22.47± 1.07c	79.38± 6.71c	0.22± 0.01c	0.79± 0.07c	0.28± 0.02c
	Pb₂₀₀	23.05± 1.62d	82.64± 10.73d	0.12± 0.01d	0.41± 0.05d	0.28± 0.02c
	Pb₃₀₀	26.40± 2.11e	106.47± 15.29e	0.09± 0.01e	0.35± 0.05e	0.25± 0.01d
G₄	Pb₁₀	16.65± 1.08a	31.18± 5.76a	1.67± 0.11a	3.12± 0.58a	0.53± 0.02a
	Pb₅₀	24.85± 0.72b	50.24± 7.62b	0.50± 0.01b	1.00± 0.15b	0.49± 0.01b
	Pb₁₀₀	32.45± 1.69c	69.92± 4.59c	0.32± 0.02c	0.70± 0.05c	0.46± 0.04c
	Pb₂₀₀	43.80± 1.25d	97.37± 13.91d	0.22± 0.01d	0.49± 0.07d	0.45± 0.01c
	Pb₃₀₀	55.25± 1.67e	143.93± 16.23e	0.18± 0.01e	0.48± 0.05d	0.38± 0.01d
G₅	Pb₁₀	5.25± 0.04a	20.39± 3.90a	0.53± 0.00a	2.04± 0.39a	0.26± 0.00a
	Pb₅₀	5.65± 0.08b	27.87± 2.35b	0.11± 0.00b	0.56± 0.05b	0.20± 0.01b
	Pb₁₀₀	8.70± 0.14c	46.14± 6.19c	0.09± 0.00c	0.46± 0.06c	0.19± 0.00bc
	Pb₂₀₀	10.25± 0.67d	58.37± 5.68d	0.05± 0.00d	0.29± 0.03d	0.18± 0.01c
	Pb₃₀₀	12.95± 1.06e	74.72± 4.06e	0.04± 0.00d	0.25± 0.01e	0.17± 0.02c
G₆	Pb₁₀	10.25± 0.87a	23.54± 4.27a	1.03± 0.09a	2.35± 0.43a	0.44± 0.02a
	Pb₅₀	19.10± 1.26b	46.78± 3.58b	0.38± 0.03b	0.94± 0.07b	0.41± 0.03b
	Pb₁₀₀	26.05± 1.63c	64.95± 7.61c	0.26± 0.02c	0.65± 0.08c	0.40± 0.02bc
	Pb₂₀₀	39.70± 1.85d	103.13± 13.86d	0.20± 0.01d	0.52± 0.07d	0.38± 0.01c
	Pb₃₀₀	48.05± 2.14e	171.68± 21.09e	0.16± 0.01e	0.57± 0.07e	0.28± 0.01d
G₇	Pb₁₀	27.45± 1.63a	32.73± 4.17a	2.75± 0.16a	3.27± 0.42a	0.84± 0.04d
	Pb₅₀	45.55± 1.08b	56.15± 4.73b	0.91± 0.02b	1.12± 0.09b	0.81± 0.02e
	Pb₁₀₀	64.10± 2.16c	73.42± 6.29c	0.64± 0.02c	0.73± 0.06c	0.87± 0.03c
	Pb₂₀₀	92.75± 4.72d	89.36± 5.40d	0.46± 0.02d	0.45± 0.03d	1.04± 0.08a
	Pb₃₀₀	94.23± 6.51e	96.74± 10.32e	0.31± 0.02e	0.32± 0.03e	0.97± 0.06b
G₈	Pb₁₀	28.60± 1.81a	39.54± 1.92a	2.86± 0.18a	3.95± 0.19a	0.72± 0.08c
	Pb₅₀	33.51± 1.25b	54.59± 6.24b	0.67± 0.03b	1.09± 0.12b	0.61± 0.02d
	Pb₁₀₀	58.37± 2.03c	63.87± 4.78c	0.58± 0.02c	0.64± 0.05c	0.91± 0.04b
	Pb₂₀₀	79.62± 2.74d	78.12± 6.13d	0.40± 0.01d	0.39± 0.03d	1.02± 0.04a
	Pb₃₀₀	93.84± 5.19e	90.57± 8.56e	0.31± 0.02e	0.30± 0.03e	1.00± 0.06a
G₉	Pb₁₀	15.30± 1.15a	25.75± 3.46a	1.53± 0.12a	2.58± 0.35a	0.59± 0.03a
	Pb₅₀	19.30± 1.24b	43.81± 5.93b	0.39± 0.02b	0.88± 0.12b	0.44± 0.02b
	Pb₁₀₀	23.05± 1.51c	61.35± 7.11c	0.23± 0.02c	0.61± 0.07c	0.38± 0.02c
	Pb₂₀₀	35.60± 1.02d	97.47± 10.25d	0.18± 0.01d	0.49± 0.05d	0.37± 0.01cd
	Pb₃₀₀	49.10± 2.63e	141.32± 11.37e	0.16± 0.01d	0.47± 0.04d	0.35± 0.02d
G₁₀	Pb₁₀	10.15± 0.58a	23.34± 3.14a	1.02± 0.06a	2.33± 0.31a	0.43± 0.02a
	Pb₅₀	17.70± 0.91b	45.52± 5.69b	0.35± 0.02b	0.91± 0.11b	0.39± 0.02b
	Pb₁₀₀	22.35± 1.74c	73.05± 5.83c	0.22± 0.02c	0.73± 0.06c	0.31± 0.03c
	Pb₂₀₀	32.60± 1.30d	102.80± 9.28d	0.16± 0.01d	0.51± 0.05d	0.32± 0.01c
	Pb₃₀₀	52.85± 2.26e	179.50± 15.02e	0.18± 0.01d	0.60± 0.05e	0.29± 0.02d
G₁₁	Pb₁₀	13.35± 1.01a	34.82± 4.33a	1.34± 0.10a	3.48± 0.43a	0.38± 0.02a
	Pb₅₀	14.25± 1.37b	55.24± 2.78b	0.29± 0.03b	1.10± 0.06b	0.26± 0.05b
	Pb₁₀₀	18.95± 2.02c	79.87± 6.19c	0.19± 0.02c	0.80± 0.06c	0.24± 0.03c
	Pb₂₀₀	25.90± 2.15d	116.26± 12.06d	0.13± 0.01d	0.58± 0.06d	0.22± 0.01c
	Pb₃₀₀	30.20± 1.87e	183.82± 20.47e	0.10± 0.01e	0.61± 0.07e	0.16± 0.02d
G₁₂	Pb₁₀	11.20± 0.62a	23.87± 4.38a	1.12± 0.06a	2.39± 0.44a	0.47± 0.01a
	Pb₅₀	18.25± 1.03b	48.35± 7.21b	0.37± 0.02b	0.97± 0.14b	0.38± 0.01b
	Pb₁₀₀	23.05± 1.47c	69.37± 8.76c	0.23± 0.01c	0.69± 0.09c	0.33± 0.02c
	Pb₂₀₀	26.30± 1.83d	85.97± 5.47d	0.13± 0.01d	0.43± 0.03d	0.31± 0.03d
	Pb₃₀₀	32.70± 2.08e	113.72± 8.95e	0.11± 0.01e	0.38± 0.03e	0.29± 0.02e
G₁₃	Pb₁₀	11.35± 1.01a	21.93± 1.22a	1.14± 0.10a	2.19± 0.12a	0.52± 0.06a
	Pb₅₀	14.20± 0.74b	39.15± 3.56b	0.28± 0.01b	0.78± 0.07b	0.36± 0.02b
	Pb₁₀₀	15.75± 1.26c	47.64± 2.17c	0.16± 0.01c	0.48± 0.02c	0.33± 0.05b
	Pb₂₀₀	17.90± 1.53d	58.29± 7.03d	0.09± 0.01d	0.29± 0.04d	0.31± 0.02c
	Pb₃₀₀	29.40± 1.79e	133.97± 10.78e	0.10± 0.01d	0.45± 0.04e	0.22± 0.03d
G₁₄	Pb₁₀	8.70± 0.34a	18.86± 2.03a	0.87± 0.03a	1.89± 0.20a	0.46± 0.02a
	Pb₅₀	13.70± 0.95b	31.33± 2.76b	0.27± 0.02b	0.63± 0.06b	0.44± 0.03b
	Pb₁₀₀	19.80± 1.23c	57.96± 6.14c	0.20± 0.01c	0.58± 0.06c	0.34± 0.02c
	Pb₂₀₀	22.05± 1.16d	82.73± 9.73d	0.11± 0.01d	0.41± 0.05d	0.27± 0.01d
	Pb₃₀₀	33.90± 1.87e	153.52± 11.25e	0.11± 0.01d	0.51± 0.04e	0.22± 0.02e

Note: Different small letters show significant difference between different concentration for each material (P< 0.05).

注:不同小写字母表示各材料不同浓度间差异显著(P< 0.05)。

表5 Pb胁迫对禾本科牧草根和地上部中Pb²⁺含量的分布 Table 5 The effect of lead stress on lead ions content in root and shoot of forage grasses

3 讨论与结论

Pb是一种有毒的重金属元素, 外源重金属铅污染物进入土壤后, 禾本科牧草可通过根系吸收土壤中的铅, 进而运输到地上部分。Pb在植物体内的过度积累会导致根系受损、分蘖减少、地上部生长减缓^[19]。本研究中, 随着Pb处理浓度的增加, 14份禾草的株高、分蘖数、地上生物量均呈现先升高后下降的趋势, 地下生物量则呈现逐渐降低的趋势(G₈除外)。可能是由于土壤中施入低浓度Pb(NO₃)₂后, Pb²⁺主要被根系吸收, 使得根的生长受到抑制, 而N $\begin{matrix} {O_{3}}^{-} \end{matrix}$ 的施入提高了土壤肥力, 从而使得地上部的生长受到促进; 随着Pb(NO₃)₂施入浓度的增大, 地上部积累的Pb²⁺也随之升高, 地上部的生长也逐渐受到抑制, 当Pb处理浓度为300 mg/kg时, 14份禾草的生长均受到明显抑制。李西等^[19]对假俭草、狗牙根(Cynodon dactylon)、结缕草的研究表明, 当Pb浓度为250 mg/kg时, 3种草的生长均受到显著抑制, 与本研究的结果基本一致。通过综合评价筛选出耐铅性最强的禾草为来自土耳其的长穗冰草G₅。

植物体内游离脯氨酸含量的增加是植物对逆境胁迫的一种生理生化反应, 脯氨酸作为细胞质渗透调节物质, 具有稳定生物大分子结构的作用, 植物通过体内游离脯氨酸的积累可防止细胞结构和功能受损以降低受伤害程度^[7]。张呈祥等^[20]研究发现当Pb浓度< 100 mg/kg时, 草地早熟禾(Poa pratensis)体内的脯氨酸含量随着Pb浓度的增大持续升高, 当Pb浓度> 100 mg/kg时, 脯氨酸含量逐渐下降。刘慧芹等^[8]的研究表明, 当Pb浓度< 1000 mg/L时, 多年生黑麦草体内的脯氨酸含量随着Pb浓度的增大而升高, 当Pb浓度> 1000 mg/L时, 脯氨酸含量逐渐下降。本研究中, 当Pb浓度< 300 mg/kg时, 7份禾草的脯氨酸含量均随着Pb处理浓度的增大而逐渐升高, 表明在该浓度范围内7份禾草均可以通过脯氨酸含量的持续升高以缓解Pb对植物的毒害作用。

SOD、CAT和POD是控制植物体内活性氧积累的最主要的酶。SOD是活性氧防御体系的第一道防线, 能歧化超氧阴离子自由基生成H₂O₂; CAT和POD又可以将H₂O₂歧化成无毒害的H₂O和O₂。李西等^[19]研究发现, 当Pb浓度为0~1000 mg/kg时, 假俭草、狗牙根、结缕草的SOD、POD、CAT活性均随着Pb处理浓度的增大而逐渐升高。本研究中, 随着Pb处理浓度的增大, 7种禾草SOD与POD活性均先升高后降低, CAT活性则一直降低, 表明SOD与POD在禾草体内超氧阴离子自由基的清除中发挥主要作用; 当Pb浓度为100 mg/kg时, 3种酶活性均处于降低状态, 表明禾草体内活性氧的积累超出了自身的清除能力, 此时大部分材料的地上与地下生物量均低于对照, 生长受到抑制。

植物体内重金属含量与植株的生物量、品种的遗传特性、生长条件及土壤中Pb浓度的含量等因素直接相关^[21]。本研究中, 随着Pb处理浓度的升高, 14份禾草地上部与根的富集系数逐渐降低, 表明Pb胁迫的加剧降低了禾草对Pb的富集效率, 另外, 除披碱草(G₇与G₈)外, 其余12份禾草的转移系数也呈现逐渐降低的趋势, 并且转移系数均小于1, 表明根是禾草富集Pb的主要器官, 从根向地上部转移Pb的能力较弱, 且会随着Pb胁迫的加剧更趋减弱。Pb超富集植物要求植株地上部Pb²⁺含量大于1000 mg/kg, 地上部生物富集系数大于1, 转移系数大于1, 且在Pb污染土壤中能够生长良好, 不会发生毒害现象^[22]。本研究中, 14份材料均未达到超富集植物的标准。披碱草(G₇与G₈)虽然在Pb处理浓度为200 mg/kg时的转移系数大于1, 但其地上部Pb²⁺含量, 地上部生物富集系数都远未达到超富集植物的标准。当Pb处理浓度为200和300 mg/kg时, G₇与G₈地上部Pb²⁺含量与转移系数均显著高于其他材料(P< 0.05), 说明其在高浓度Pb胁迫下具有较强的Pb吸收与富集转运能力, 可作为Pb污染土壤修复的候选植物。

综合而言, 来自土耳其的长穗冰草G₅具有较强的耐Pb性, 而披碱草G₇与G₈则具有较强的Pb富集转运能力, 是否能将披碱草用于Pb污染土壤的生态修复还需要进一步的大田试验进行验证。

The authors have declared that no competing interests exist.

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[20]	Zhang C X, Chen W F, Pei H C. Responses of Kentucky bluegrass to lead stress and accumulation characteristics of lead. Chinese Journal of Grassland , 2013, 35(1): 96-101. [本文引用:1]
[21]	Zhao X L, Liu X. Differences in plant growth, Cd and nutrient uptake, Cd translocation between two tobacco cultivars under Cd stress. Journal of Soil and Water Conservation, 2009, 23(1): 117-121. [本文引用:1]
[22]	Wang S L, Liao W B, Yu F Q. Hyperaccumulation of lead, zinc, and cadmium in plants growing on a lead/zinc outcrop in Yunnan Province, China. Environmental Geology, 2009, 58(3): 471-476. [本文引用:1]
[1]	秦天才, 吴玉树, 王焕校, 等. 镉、铅及其相互作用对小白菜根系生理生态效应的研究. 生态学报, 1998, 18(3): 320-325. [本文引用:1]
[2]	杜连彩. 植物耐铅生态型及对铅胁迫的耐性机理. 生物学教学, 2007, 32(2): 2-3. [本文引用:1]
[5]	李璇, 岳红, 王升, 等. 影响植物抗氧化酶活性的因素及其研究热点和现状. 中国中药杂志, 2013, 38(7): 973-978. [本文引用:1]
[7]	谢传俊, 杨集辉, 周守标, 等. 铅递进胁迫对假俭草和结缕草生理特性的影响. 草业学报, 2008, 17(4): 65-70. [本文引用:2]
[8]	刘慧芹, 韩巨才, 刘慧平, 等. 铅梯度胁迫对多年生黑麦草幼苗生理生活特性影响. 草业学报, 2012, 21(6): 57-63. [本文引用:2]
[9]	季杨, 张新全, 彭燕, 等. 干旱胁迫对鸭茅根、叶保护酶活性、渗透物质含量及膜质过氧化作用的影响. 草业学报, 2014, 23(3): 144-151. [本文引用:1]
[10]	钱海燕, 王兴祥, 蒋佩兰, 等. 黑麦草连茬对铜、锌污染土壤的耐性及其修复作用. 江西农业大学学报, 2004, 26(5): 801-804. [本文引用:1]
[12]	李合生. 植物生理生化实验原理和技术[M]. 北京: 高等教育出版社, 2002: 258-261. [本文引用:1]
[14]	刘祖祺, 张石城. 植物抗性生理学[M]. 北京: 中国农业出版社, 1994: 370-372. [本文引用:1]
[18]	李源, 刘贵波, 高洪文, 等. 紫花苜蓿种质耐盐性综合评价及盐胁迫下的生理反应. 草业学报, 2010, 19(4): 79-86. [本文引用:1]
[19]	李西, 吴亚娇, 孙凌霞. 铅胁迫对三种暖季型草坪草生长和生理特性的影响. 草业学报, 2014, 23(4): 171-180. [本文引用:3]
[20]	张呈祥, 陈为峰, 裴洪翠. 草地早熟禾对铅的胁迫反应及积累特性. 中国草地学报, 2013, 35(1): 96-101. [本文引用:1]
[21]	赵秀兰, 刘晓. 同品种烟草生长和镉及营养元素吸收对镉胁迫响应的差异. 水土保持学报, 2009, 23(1): 117-121. [本文引用:1]

1998

0.0

. 1998, 18(3):320-325

镉、铅及其相互作用对小白菜根系生理生态效应的研究

秦天才, 吴玉树, 王焕校

The physiological and ecological effects on root system of Brassica chinensis grown in hydroponic culture under the stresses at different concentration of Cd and Pb were studied.The experimental results show that the Cd solution concentration of greater than 0.1 mg/L significantly inhibited the root growth, decreased the number of lateral roots,suppressed the root branching,lowered the root biomass and volume,hindered the development of root system,depressed the uptake of Mn,Zn by root,reduced the root ac...

采用溶液培养方法，以镉、铅作为胁迫因子，研究了不同镉、铅浓度对小白菜根系生理生态的影响。实验结果表明：培养液中镉超过０．１ｍｇ／Ｌ以后，侧根数目减少，根的分枝程度降低，根系生物量和体积下降，根系生长发育受阻，根系不发达，根系对锰、锌的吸收能力受到抑制，根系活动降低，对硝酸盐吸收能力下降，蛋白质分解加快，游离氨基酸积累，氮代谢紊乱、失调。在含镉的培养液中，施入铅，由于铅的加入，加强了镉对根系的生理生态效应。

... 铅(Pb)是最严重的环境重金属污染物之一^[1] ...

2007

0.0

... Pb在植物根、茎、叶及籽粒中的累积,不仅严重影响植物的生长发育、降低产量和质量^[2],并通过生物链富集而对人类健康造成严重的威胁,成为环境治理中越来越突出的问题 ...

2001

0.0

... 活性氧能够快速地与DNA、脂类、蛋白质等反应从而造成细胞损伤^[3,4] ...

2001

0.0

... 活性氧能够快速地与DNA、脂类、蛋白质等反应从而造成细胞损伤^[3,4] ...

2013

0.0

... 在逆境胁迫下,植物体内的活性氧数量剧增,植物的抗氧化酶活性迅速升高,对清除活性氧起到重要的应激反应,成为环境胁迫下应激反应的重要检测指标^[5] ...

2005

0.0

. 2005, 60(1):97-104

Lead induced changes in antioxidant metabolism of horsegram (Macrotyloma uniflorum (Lam.) Verdc.) and bengalgram (Cicer arietinum L.).

Reddy A M , Kumar S G , Jyothsnakumari G

College of Pharmacy and Research Center for Bioresources and Health, Chungbuk National University, Cheongju 361-763, South Korea.

One-month old horsegram (Macrotyloma uniflorum (Lam.) Verdc. cv VZM1) and bengalgram (Cicer arietinum L. cv Annogiri) were exposed to different regimes of lead stress as Pb(NO3)2 at 0, 200, 500 and 800 ppm concentrations. The extent of oxidative damage as the rate of lipid peroxidation, antioxidative response and the accumulation of lead in roots and shoots of both plants were evaluated after 12 days of lead stress. Lead (Pb) treated plants showed increased levels of lipid peroxidation as evidenced from the increased malondialdehyde content coupled with the increase in the activities of superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), glutathione reductase (GR), glutathione S-transferase (GST) compared to control (untreated) plants. Lead stress caused significant changes in the activity of antioxidative enzymes. The effect of lead was found to be concentration dependent. Higher concentration of lead (800 ppm) resulted 2- to 3-fold increase in SOD, catalase and peroxidase activities, 3- to 5-fold increase in GR activity and 3- to 4-fold increase in GST activity in roots and leaves of both horsegram and bengalgram plants. Lead stress caused a significant increase in the rate of peroxidation as showed in the levels of malondialdehyde content in roots and leaves of both plant species. Horsegram registered lower Pb accumulation than bengalgram, however localization of Pb was greater in roots than leaves in both plants. In general, lipid peroxide levels and antioxidative enzyme activities were higher in horsegram than bengalgram and also more in roots than leaves which best concordance with the lead contents of both the plants and organs. These results suggest that Pb toxicity causes oxidative stress in plants and the antioxidative enzymes SOD, CAT, POD, GR, GST could play a pivotal role against oxidative injury.

PMID: 15910908

... Ventus)与豌豆(Pisum sativum)根部、水稻(Oryza sativa)植株、玉米(Zea mays)愈伤组织等活性氧的增加与抗氧化酶活性的增强^[6] ...

2008

0.0

... 另有研究表明,Pb胁迫会导致假俭草(Eremochloa ophiuroides)、结缕草(Zoysia japonica)、多年生黑麦草(Lolium perenne)等植物体内脯氨酸含量的升高^[7,8] ...

... 植物体内游离脯氨酸含量的增加是植物对逆境胁迫的一种生理生化反应,脯氨酸作为细胞质渗透调节物质,具有稳定生物大分子结构的作用,植物通过体内游离脯氨酸的积累可防止细胞结构和功能受损以降低受伤害程度^[7] ...

2012

0.0

. 2012, 21(6):57-63 DOI:10.11686/cyxb20120608

铅梯度胁迫对多年生黑麦草幼苗生理生活特性影响

刘慧芹, 韩巨才, 刘慧平

本试验以盆栽黑麦草幼苗为材料，研究了不同的胁迫时间（７，１４，２１，２８ｄ），不同的铅浓度（５００，１０００，１５００ｍｇ／Ｌ）对黑麦草的抗氧化酶（ＳＯＤ、ＰＯＤ）、细胞膜（ＭＤＡ、相对电导率）及渗透调节物质（ＳＳ、Ｐｒｏ）的影响。结果表明，随着铅浓度的增加，黑麦草叶片中的ＳＯＤ活性变化整体为先上升后下降，在低浓度（５００和１０００ｍｇ／Ｌ）和短时间（７和１４ｄ）胁迫下ＳＯＤ活性明显升高，之后快速降低。ＰＯＤ活性随着胁迫时间及铅浓度增加呈显著的下降趋势，在２８ｄ时，１５００ｍｇ／Ｌ浓度下，ＰＯＤ活性最低，为４５．９Ｕ／ｇ。随着胁迫时间及铅浓度的增加，ＭＤＡ含量及相对电导率整体呈上升趋势，且ＭＤＡ含量与铅浓度呈线性正相关（ r ２＞０．９６）。可溶性糖（ＳＳ）含量变化复杂，在较高浓度及较长时间作用下趋于减少。脯氨酸（Ｐｒｏ）含量在较低铅浓度胁迫下会明显增加，但浓度过高超过黑麦草忍耐极限，就会有所下降。表明黑麦草在重金属铅胁迫中经历了一个忍耐和逐渐受损的过程。

... 另有研究表明,Pb胁迫会导致假俭草(Eremochloa ophiuroides)、结缕草(Zoysia japonica)、多年生黑麦草(Lolium perenne)等植物体内脯氨酸含量的升高^[7,8] ...

... 刘慧芹等^[8]的研究表明,当Pb浓度#cod#x0003C ...

2014

0.0

. 2014, 23(3):144-151 DOI:10.11686/cyxb20140316

干旱胁迫对鸭茅根、叶保护酶活性、渗透物质含量及膜质过氧化作用的影响

季杨, 张新全, 彭燕

1.Department of Grassland, College of Animal Science and Technology, Sichuan Agricultural University, Ya’an 625014, China; 2.Sichuan Animal Science Academy, Chengdu 610066, China

To elucidate the mechanism of drought tolerance in orchardgrass, the different responses associated with lipid peroxidation, osmotic adjustment and activity of protective enzymes in the root and leaf to drought stress of two different genotypes of orchardgrass (drought-sensitive “01998” and drought-tolerant “Baoxing”) were investigated. With an extension of drought stress, MDA content and electrolyte leakage in the root and leaf of the two orchardgrasses increased, and total soluble sugar content and free proline content also accumulated. At the same time, soluble protein content, SOD, CAT, POD, APX activities increased initially and then decreased. The accumulation of leaf MDA content and membrane permeability grew fast, indicating that damage on the blades was far more serious than on roots under constant drought stress. Accumulation of osmotic substances, leaf soluble sugar and soluble protein content were higher in shoots than in the roots, while the relative increase of free amino acid was greater in the roots. This might be because the blade is the main area for sugar production, whereas the root system is closely related to the synthesis of amino acids. In addition, APX and POD activities in the roots and leaves of “Baoxing” were higher than those in “01998” under 24 d drought stress, indicating that its ability to scavenge singlet oxygen and H 2 O 2 was not weakened by drought stress. Drought tolerant “Baoxing” showed more active and stable peroxidation ability under drought stress.

以2种不同耐旱性的鸭茅基因型(敏感型“01998”和耐旱型“宝兴”) 为研究对象,研究干旱胁迫下鸭茅根、叶膜质过氧化作用,渗透调节和保护酶活性的生理变化,探讨鸭茅耐旱机制。结果表明, 随着干旱胁迫时间的延长,2种基因型鸭茅根系及叶片电导率,丙二醛含量逐渐增加,渗透调节物质可溶性糖和游离脯氨酸不断积累,而可溶性蛋白含量、超氧化物歧化酶、过氧化氢酶、过氧化物酶和抗坏血酸过氧化物酶活性呈先上升后下降趋势。其中,叶片脂膜过氧化产物MDA累积和膜透性增幅较大,说明在持续的干旱胁迫下叶片所受伤害重于根系。而渗透物质积累方面,叶片中可溶性糖和可溶性蛋白的含量高于根系,而根系中的游离氨基酸的相对增加量则大于叶片,这可能与叶片是糖的主要产生部位,而根系则可以合成氨基酸有关。研究还表明,干旱胁迫第24天,耐旱型品种“宝兴”根系及叶片APX、POD活性显著高于“01998” 表明重度干旱胁迫并没有降低APX和POD酶清除H 2 O 2 和单态氧的能力,说明“宝兴”鸭茅在干旱条件下抗氧化清除系统响应更积极、更持久。

... 脯氨酸的积累可以调节细胞内的渗透势,维持水分平衡,保护细胞内重要代谢活动所需的酶类活性,为植物适应逆境胁迫的基本特征之一^[9] ...

2004

0.0

... 钱海燕等^[10]研究发现黑麦草对Cu、Zn污染土壤有一定的耐性及修复作用 ...

2005

0.0

. 2005, 60(3-4):362-367

Vegetation pattern and heavy metal accumulation at a mine tailing at Gyongyosoroszi, Hungary.

Tamas J , Kovacs A.

Department of Water Environmental Management, Center of Argicultural Sciences, University of Debrecen, Debrecen, Hungary.

Vegetation at an abandoned heavy metal bearing mine tailing may have multifunctional roles such as modification of water balance, erosion control and landscape rehabilitation. Research on the vegetation of mine tailings can provide useful information on tolerance, accumulation and translocation properties of species potentially applicable at moderately contaminated sites. Analyses of the relationship between heavy metal content (Pb, Zn and Cu) and vegetation in a mine tailing were carried out. These analyses included: (1) spatial analysis of relationship among heavy metal distribution, pH and vegetation patterns, and (2) analysis of heavy metal accumulation and translocation in some plant species. Presence of vegetation was found to be significantly dependent on pH value, which confirms that phytotoxicity is a function of element concentration in solution, which is primarily controlled by pH value in mine tailings. Among the most abundant plant species, dewberry (Rubus caesius), vipersbugloss (Echium vulgare), scarlet pimpernel (Anagallis arvensis) and narrowleaf plantain (Plantago lanceolata) accumulate significant amounts of Pb, Cu and Zn, while in the case of annual bluegrass (Poa annua) only Pb can be measured in elevated contents. Considering the translocation features, scarlet pimpernel, narrowleaf plantain, and dewberry accumulate heavy metals primarily in their roots, while heavy metal concentration in vipersbugloss and annual bluegrass is higher in the shoots.

PMID: 15948607

... Tamas和Kovacs^[11]认为早熟禾(Poa spp ...

2002

0.0

... Pro含量的测定参照李合生^[12]的酸性茚三酮比色法, CAT活性的测定参照Dhindsa等^[13]的紫外吸收法,POD活性的测定参照刘祖祺和张石城^[14]的愈创木酚法, SOD活性的测定参照Cao等^[15]的NBT光还原法 ...

1981

0.0

1994

0.0

2009

0.0

. 2009, 64(3-4):231-

Lack of Salicylic acid in Arabidopsis protects plants against moderate salt stress.

Cao Y , Zhang Z W , Xue L W

Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment, College of Life Science, Sichuan University, Chengdu 610064, China.

Previous studies showed that salicylic acid (SA)-deficient transgenic Arabidopsis expressing the salicylate hydroxylase gene NahG had a higher tolerance to moderate salt stress. SA may potentiate the stress response of germination and growth of Arabidopsis seedlings by inducing reactive oxygen species (ROS). However, the detailed mechanism for a better adaption of NahG plants to moderate salt stress is largely unknown. In the present study we found that a higher GSH/GSSG (glutathione/oxidized glutathione) ratio and ASA/DHA (ascorbic acid/dehydroascorbate) ratio in NahG plants during the stress may be the key reason for their stress-tolerance advantage. NahG plants actually could not produce more active antioxidant enzymes than the wild-type ones under natural conditions, but maintain higher activities of glutathione reductase (GR) and dehydroascorbate reductase (DHAR) during the stress. Hereby, the reduced glutathione and reduced ascorbic acid contents are higher in NahG plants under salt stress. However, NahG plants do not adapt better under severe salt stress. All antioxidant enzyme activities, GSH/GSSG ratio and ASA/DHA ratio declined substantively at 400 mM NaCl stress in both NahG and wild-type seedlings.

PMID: 19526718

1983

0.0

... 生物富集系数(bioconcentration factor, BCF)=植物地上或根系Pb²⁺积累浓度/土壤中Pb²⁺浓度^[16] ...

1994

0.0

... 转运系数(translocation factor, TF)=地上部Pb²⁺积累浓度/根中Pb²⁺积累浓度^[17] ...

2010

0.0

. 2010, 19(4):79-86 DOI:10.11686/cyxb20100411

紫花苜蓿种质耐盐性综合评价及盐胁迫下的生理反应

李源, 刘贵波, 高洪文

以中苜１号为对照，对来自俄罗斯的１８份紫花苜蓿种质的耐盐性进行了综合评价，并对盐胁迫下的生理反应进行了初步研究。结果表明，运用标准差系数赋予权重法进行综合评价，不但考虑了不同指标的权重，还定量的鉴定出了每份材料的耐盐能力，比聚类分析的结果更具科学合理性，试验共筛选出Ｍ７、Ｍ９、Ｍ１５、８１０共４份耐盐性强的种质；在此基础上，进一步探讨了盐胁迫下的生理反应，除叶水势随着盐浓度的增加呈下降趋势外，游离脯氨酸含量、可溶性糖含量、细胞质膜透性、丙二醛含量、水分饱和亏缺则呈上升趋势，且不同材料变化幅度不同。可溶性糖含量、细胞质膜透性、丙二醛含量、水分饱和亏缺和叶水势等指标很好的反映了材料间的耐盐性，可直接作为耐盐评价的鉴定指标。

... 3 耐Pb性综合评价利用株高、分蘖数、地上与地下生物量等生长指标,采用标准差系数赋予权重法^[18]对14份禾草进行耐铅性综合评价 ...

2014

0.0

. 2014, 23(4):171-180 DOI:10.11686/cyxb20140421

铅胁迫对三种暖季型草坪草生长和生理特性的影响

李西, 吴亚娇, 孙凌霞

College of Landscape Architecture,Sichuan Agricultural University,Chengdu 611130,China

In order to explore the mechanism of Pb accumulation and transportation in plant tissue,the growth and physiological responses of turfgrass under soil Pb stress were evaluated in a pot experiment with three warm-season turfgrass species: Eremochloa ophiuroides (centipedegrass), Cynodon dactylon (bermudagrass),and Zoysia japonica (zoysiagrass). By applying Pb of different concentrations to the soil,CK(0 mg/kg)and five Pb treatments as the following 250,500,1000,2000,4000 mg/kg were set in this experiment. Our results showed that there is a significant decrease of the visual quality and leaf relative water content under 4000 mg/kg treatment comparing with control. Leaf chlorophyll a and b content significantly reduced under 4000 mg/kg treatment comparing with control among all three turfgrasses. The electrolyte leakage in leave gradually rises with the increase of Pb level among all three turfgrasses. These results suggested that cell membrane of leave is damaged by application of Pb. The antioxidant defense system (superoxide dismutase/SOD,catalase/CAT,peroxidase/POD) was greatly activated under the various Pb stress among three turfgrasses species. Under all four Pb treatments in centipedgrass,the activity of SOD gradually rises and reaches a maximum at 20 day after Pb application,and the activity of CAT at day 5 after Pb treatment is greatly higher than that in control. While the activity of POD increases significantly only under 2000 and 4000 mg/kg Pb treatments and reaches the maximum at day 15 after Pb application in centipedigrass. Under all four Pb treatments in bermudagrass,the activity of SOD rises at day 5 after Pb treatment and boosts a maximum at day 25,and the activity of CAT reaches a maximum at 15 day after treatment. While the activity of POD in Pb treatments rises gradually with the accumulation of Pb in soil and reaches a maximum at day 30 in all Pb treatments. The activity of SOD is significantly higher under 4000 mg/kg treatment than that in control and reaches a maximum at 15 day after treatment in zoysiagrass. While the activity of POD reaches a maximum at day 25 after treatment and then drops at day 30,activity of CAT shows a similar trend as that of POD and reaches a maximum at day 15 after treatment. These data implied that the protection capacity of three enzymes varied among three grass species under lead stress. Combing with the growth effect,we concluded that Pb resistance from high to low among three turfgrass species is in the following order: bermudagrass>zoysiagrass>centipedegrass.

采用盆栽试验,研究了铅胁迫对假俭草、狗牙根与结缕草3种暖季型草坪草生长和生理特性的影响。通过向土壤中添加不同浓度的铅,研究铅积累对草坪外观质量、生物量、相对含水量、叶片电导率、叶绿素含量及抗氧化酶系统的影响。实验结果表明,随着铅胁迫浓度的增加,3种草坪草外观质量、根系生物量、相对含水量及叶绿素含量同对照相比均显著下降,地上部生物量下降幅度相对较小,而叶片中的电导率显著增加。不同浓度铅胁迫下,3种草内3种保护酶的反应程度不同。在各个铅胁迫水平下,假俭草叶片SOD活性逐渐升高,在20 d时达到最大值;CAT活性自处理后5 d时相比对照显著升高,此后基本维持在同一水平;而只有在2000和4000 mg/kg铅胁迫水平下,POD活性显著升高,处理后25 d时达到最大值。狗牙根在各胁迫水平下,SOD活性自处理后5 d时均升高,25 d时骤升至最大值;在15 d时CAT活性达到最大值; POD活性均呈现上升趋势。结缕草叶片SOD活性在最高胁迫水平下处理5 d后急剧升高,15 d时达到最大值;POD活性均呈现先上升后降低的趋势,25 d时达到最大值;CAT活性先升高后降低,在15 d时达到最大值。对照3种草坪草对铅胁迫的响应变化具有差异,通过分析得出3种草坪草对铅抗性能力依次排序为:狗牙根>结缕草>假俭草。

... Pb在植物体内的过度积累会导致根系受损、分蘖减少、地上部生长减缓^[19] ...

... 李西等^[19]对假俭草、狗牙根(Cynodon dactylon)、结缕草的研究表明,当Pb浓度为250 mg/kg时,3种草的生长均受到显著抑制,与本研究的结果基本一致 ...

... 李西等^[19]研究发现,当Pb浓度为0~1000 mg/kg时,假俭草、狗牙根、结缕草的SOD、POD、CAT活性均随着Pb处理浓度的增大而逐渐升高 ...

2013

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... 张呈祥等^[20]研究发现当Pb浓度#cod#x0003C ...

2009

0.0

... 植物体内重金属含量与植株的生物量、品种的遗传特性、生长条件及土壤中Pb浓度的含量等因素直接相关^[21] ...

2009

0.0

... Pb超富集植物要求植株地上部Pb²⁺含量大于1000 mg/kg,地上部生物富集系数大于1,转移系数大于1,且在Pb污染土壤中能够生长良好,不会发生毒害现象^[22] ...

1998

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. 1998, 18(3):320-325

镉、铅及其相互作用对小白菜根系生理生态效应的研究

秦天才, 吴玉树, 王焕校

... 铅(Pb)是最严重的环境重金属污染物之一^[1] ...

2007

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2013

0.0

2008

0.0

... 另有研究表明,Pb胁迫会导致假俭草(Eremochloa ophiuroides)、结缕草(Zoysia japonica)、多年生黑麦草(Lolium perenne)等植物体内脯氨酸含量的升高^[7,8] ...

2012

0.0

. 2012, 21(6):57-63 DOI:10.11686/cyxb20120608

铅梯度胁迫对多年生黑麦草幼苗生理生活特性影响

刘慧芹, 韩巨才, 刘慧平

... 另有研究表明,Pb胁迫会导致假俭草(Eremochloa ophiuroides)、结缕草(Zoysia japonica)、多年生黑麦草(Lolium perenne)等植物体内脯氨酸含量的升高^[7,8] ...

... 刘慧芹等^[8]的研究表明,当Pb浓度#cod#x0003C ...

2014

0.0

. 2014, 23(3):144-151 DOI:10.11686/cyxb20140316

干旱胁迫对鸭茅根、叶保护酶活性、渗透物质含量及膜质过氧化作用的影响

季杨, 张新全, 彭燕

1.Department of Grassland, College of Animal Science and Technology, Sichuan Agricultural University, Ya’an 625014, China; 2.Sichuan Animal Science Academy, Chengdu 610066, China

... 脯氨酸的积累可以调节细胞内的渗透势,维持水分平衡,保护细胞内重要代谢活动所需的酶类活性,为植物适应逆境胁迫的基本特征之一^[9] ...

2004

0.0

... 钱海燕等^[10]研究发现黑麦草对Cu、Zn污染土壤有一定的耐性及修复作用 ...

2002

0.0

1994

0.0

2010

0.0

. 2010, 19(4):79-86 DOI:10.11686/cyxb20100411

紫花苜蓿种质耐盐性综合评价及盐胁迫下的生理反应

李源, 刘贵波, 高洪文

... 3 耐Pb性综合评价利用株高、分蘖数、地上与地下生物量等生长指标,采用标准差系数赋予权重法^[18]对14份禾草进行耐铅性综合评价 ...

2014

0.0

. 2014, 23(4):171-180 DOI:10.11686/cyxb20140421

铅胁迫对三种暖季型草坪草生长和生理特性的影响

李西, 吴亚娇, 孙凌霞

College of Landscape Architecture,Sichuan Agricultural University,Chengdu 611130,China

... Pb在植物体内的过度积累会导致根系受损、分蘖减少、地上部生长减缓^[19] ...

... 李西等^[19]对假俭草、狗牙根(Cynodon dactylon)、结缕草的研究表明,当Pb浓度为250 mg/kg时,3种草的生长均受到显著抑制,与本研究的结果基本一致 ...

... 李西等^[19]研究发现,当Pb浓度为0~1000 mg/kg时,假俭草、狗牙根、结缕草的SOD、POD、CAT活性均随着Pb处理浓度的增大而逐渐升高 ...

2013

0.0

... 张呈祥等^[20]研究发现当Pb浓度#cod#x0003C ...

2009

0.0

... 植物体内重金属含量与植株的生物量、品种的遗传特性、生长条件及土壤中Pb浓度的含量等因素直接相关^[21] ...