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1.
The interaction between zinc and cadmium was investigated in tomato plants (Solanum lycopersicum). Ten-day-old seedlings were treated with 10 μmol/L CDC12 associated to different concentrations of ZnC12 (10, 50, 100, and 150 μmol/L). Zn supply clearly reduced Cd accumulation in leaves and simultaneously increased Zn concentration. Cd induced oxidative stress in leaves as indicated by an increase in thiobarbituric acid-reactive substances (TBARS) level and chlorophyll breakdown. Furthermore, compared with control, Cdtreate plants had significantly higher activities of superoxide dismutase (SOD, EC 1.15.1.1), whereas, catalase (CAT, EC 1.111.1.6),ascorbate peroxidase (APX, EC 1.11.1.11), and glutathione reductase (GR, EC 1.6.4.2) activities were significantly suppressed by Cd addition. Zn supplementation, at low level, restored and enhanced the functional activity of these enzymes (SOD, CAT, APX and GR) as compared to Cd-alone-treated plants. The beneficial effect of adequate Zn level on Cd toxicity was confirmed by a significant decrease in TBARS level and restoration of chlorophyll content. However, when Zn was added at high level in combination with Cd there was an accumulation of oxidative stress, which was higher than that for Cd or excess Zn alone treatments. These results suggested that higher Zn concentrations and Cd are synergistic in their effect on plant growth parameters and oxidative stress.  相似文献   

2.
采用水培试验,研究了镉胁迫下喷施细胞分裂素类物质6-苄氨基嘌呤(6-BA)和激动素(KT)对玉米幼苗生长、叶片叶绿素含量、脯氨酸含量、植株镉含量和活性氧清除酶活性的影响.结果表明,与单纯镉胁迫相比,喷施6-BA和KT提高了玉米幼苗的生物量、根和地上部镉含量、叶绿素和脯氨酸含量,降低了叶片丙二醛(MDA)含量,促进了叶片过氧化物酶(POD)和过氧化氢酶(CAT)活性的升高,但对超氧化物歧化酶(SOD)活性的影响不明显.说明细胞分裂素类物质6-BA和KT可缓解镉胁迫对玉米幼苗的伤害,其机制可能与细胞分裂素物质能维持叶绿素稳定、刺激细胞内H2O2清除酶类活性及促进脯氨酸积累有关.当6-BA浓度在0~20mg·L-1之间时,其对玉米幼苗镉胁迫的缓解效应随喷施浓度的提高而增强,而KT的最适喷施浓度为70mg·L-1.  相似文献   

3.
The interaction between zinc and cadmium was investigated in tomato plants (Solanum lycopersicum). Ten-day-old seedlings were treated with 10 mol/L CdCl2 associated to di erent concentrations of ZnCl2 (10, 50, 100, and 150 mol/L). Zn supply clearly reduced Cd accumulation in leaves and simultaneously increased Zn concentration. Cd induced oxidative stress in leaves as indicated by an increase in thiobarbituric acid-reactive substances (TBARS) level and chlorophyll breakdown. Furthermore, compared with control, Cdtreated plants had significantly higher activities of superoxide dismutase (SOD, EC 1.15.1.1), whereas, catalase (CAT, EC 1.111.1.6), ascorbate peroxidase (APX, EC 1.11.1.11), and glutathione reductase (GR, EC 1.6.4.2) activities were significantly suppressed by Cd addition. Zn supplementation, at low level, restored and enhanced the functional activity of these enzymes (SOD, CAT, APX and GR) as compared to Cd-alone-treated plants. The beneficial e ect of adequate Zn level on Cd toxicity was confirmed by a significant decrease in TBARS level and restoration of chlorophyll content. However, when Zn was added at high level in combination with Cd there was an accumulation of oxidative stress, which was higher than that for Cd or excess Zn alone treatments. These results suggested that higher Zn concentrations and Cd are synergistic in their e ect on plant growth parameters and oxidative stress.  相似文献   

4.
通过盆栽试验研究了模拟酸雨(pH分别为3.5、4.5、5.6)和Pb(0~2000 mg·kg-1)复合污染对芥菜型油菜紫叶芥的生理特性和Pb富集的影响.结果表明,在酸雨和Pb复合污染下,紫叶芥生物量和叶绿素含量均有不同程度的下降,叶和根中的超氧化物歧化酶(SOD)和过氧化物酶(POD)活性随着Pb含量和酸雨强度的增加是先升后降,脯氨酸含量随着Pb含量和酸雨强度的增加而升高.芥菜型油菜以通过调节抗氧化酶系统和提高脯氨酸含量来应对酸雨和重金属胁迫,芥菜型油菜对酸雨和Pb的复合污染有很强的耐受能力.芥菜型油菜根和地上部分Pb含量随Pb处理含量水平的增大而增加,其中,根对Pb的富集能力大于地上部分,酸雨能够促进芥菜型油菜对Pb的吸收.因此,在酸雨地区可以选用芥菜型油菜作为Pb污染土壤的修复植物.  相似文献   

5.
镉胁迫对小麦叶片细胞膜脂过氧化的影响   总被引:61,自引:0,他引:61       下载免费PDF全文
镉胁迫使植物体内活性氧自由基清除系统的功能降低,造成细胞内H2O2积累,抗坏血酸过氧化酶和谷胱甘肽还原酶活性下降,内源抗氧化剂抗坏血酸和谷胱甘肽含量减少,小麦叶片的组织自动氧化速率显著提高。细胞内丙二醛的积累表明,膜脂过氧化发生和膜系统受到损伤。推测小麦镉伤害过程中,活性氧自由基代谢失衡造成的膜脂过氧化起着重要作用。  相似文献   

6.
Cd胁迫下超富集植物圆锥南芥抗氧化机理   总被引:12,自引:2,他引:10  
采用土培的方法研究了不同Cd2+添加量(0、10、20、40、80、160、240mg.kg-1)对多金属超富集植物圆锥南芥(Arabis paniculata Franch)抗氧化酶(超氧化物歧化酶SOD、过氧化氢酶POD、抗坏血酸过氧化物酶CAT、过氧化物酶APX)活性、非酶物质(巯基SH、谷胱甘肽GSH、植物络合素PCs)含量以及生物量、叶绿素、丙二醛(MDA)、半胱氨酸(Cysteine)、脯氨酸(Proline)含量的影响.结果表明,随着Cd添加量的增加,圆锥南芥的生物量、Cd含量、富集系数、转运系数呈增加趋势,SOD活性、叶绿素含量呈下降趋势.POD、CAT、APX活性以及MDA含量均呈先升高后降低的变化趋势.圆锥南芥叶片中SH、GSH、PCs含量随Cd添加量的增加而增加,当Cd添加量为240mg.kg-1时,SH、GSH、PCs含量分别比对照提高了92.7%、70.2%、143.4%,表明SH、GSH、PCs在解毒Cd毒害中起着重要作用.  相似文献   

7.
Piriformospora indica, a root-colonizing endophytic fungus of Sebacinales, promotes plant growth and confers resistance against biotic and abiotic stresses. In order to confirm the influence of P. indica on growth, proline, malondialdehyde (MDA), chlorophyll, and cadmium (Cd) amounts in Nicotiana tabacum under Cd stress, hydroponics, pot and field trials were conducted. The results showed that P. indica can store Cd in plant roots and reduce leaf Cd content, reduce the concentration of MDA, and increase the proline and chlorophyll content and the activities of catalase, peroxidase, and superoxide dismutase under hydroponic Cd stress. RT-PCR analysis showed that the relative expression level of genes Gsh2, TaPCS1, oas1, GPX, and Hsp70 in colonized plants was 4.3, 1.4, 2.9, 1.7, and 6.9 fold higher than in un-colonized plants respectively. Cd exposure significantly reduced un-colonized plants'' agronomic traits compared to P. indica-colonized ones. Our results suggested that P. indica can sequester Cd in roots, so that much less cadmium was transported to leaves, and the increased concentrations of antioxidant enzymes, pigments and proline contents, as well as the higher expression of stress-related phytochelatin biosynthesis genes in P. indica-inoculated plants, may also serve to protect N. tabacum plants against oxidative damage, enhancing Cd tolerance.  相似文献   

8.
曹欣  魏群  苏苑  廖运生  金锂 《环境工程》2020,38(2):77-80,127
为研究镉胁迫下蛋白核小球藻生物膜的生理响应及其去除效果,实验设计了不同的镉初始浓度梯度,分析镉胁迫下蛋白核小球藻生物膜的叶绿素a、硝酸还原酶、胞外多聚糖(EPS)等生理特征指标,并比较了蛋白核小球藻生物膜在不同的镉初始浓度下对镉的去除效果。结果表明:镉会抑制蛋白核小球藻生物膜的生长及其硝酸还原酶的产生,并且抑制程度随着镉初始浓度的增大而增加,20 mg/L的镉还会导致部分藻类生物膜的死亡;另外,镉会抑制蛋白核小球藻生物膜EPS的产生,但随着接触时间的增加,镉会刺激藻类生物膜分泌少量EPS来阻止镉离子进入藻细胞;镉初始浓度为15 mg/L时,蛋白核小球藻生物膜对镉的去除效果最好,达到89.83%。以上成果可为藻类生物膜去除重金属镉的后续研究奠定基础。  相似文献   

9.
本文研究了不同浓度的CuSO4对55-65代松江鲈肾细胞系的毒性效应。采用MTT法测得CuSO4 24 h LC50为154.34 μmol/L。酶活力测定的结果显示:超氧化物歧化酶(SOD)和谷胱甘肽-S-转移酶(GST)的活性在CuSO4浓度为0~300 μmol/L时,随浓度的升高逐渐升高,在300 μmol/L时达到最大值;谷胱甘肽过氧化物酶(GSH-Px)的活性在CuSO4浓度为100 μmol/L时达到最大值,随后随着CuSO4浓度的降低逐渐降低。微核率随CuSO4浓度增加而增加,最高达14.33‰,彗星实验发现在半致死浓度条件下松江鲈肾细胞拖尾率为54.00%、迁移长度18.41±2.94 μm,与对照组差异显著(p <0.05)。认为CuSO4会引起细胞氧化酶活性的改变以及细胞核DNA损伤。松江鲈肾细胞系可以作为Cu2+污染的监测指标。  相似文献   

10.
为探究黄芪幼苗对铜离子(Cu2+)胁迫的耐性机理以及凹凸棒黏土对Cu2+污染的缓解作用,研究了不同浓度CuSO4(2~20mmol/L)胁迫对黄芪幼苗的生理学毒性与凹凸棒黏土的缓解作用.结果表明,2mmol/L CuSO4胁迫使得根系Cu2+含量、H2O2(过氧化氢)含量、MDA(丙二醛)含量分别较对照显著上升1.82倍、1.04倍、2.14倍.CuSO4胁迫浓度达8mmol/L时,根系SOD(超氧化物歧化酶)活性、根尖膜损伤程度和叶片Cu2+含量分别较对照显著上升1.13倍、1.12倍和2.62倍;同时,叶片PS Ⅱ(光系统II)实际光化学效率[Y(II)]、光化学淬灭系数(qP)、PSⅡ电子传递速率(ETR)和叶绿素含量较对照分别显著降低22.88%、24.44%、21.49%和28.31%,而NPQ和qN(非光化学荧光猝灭系数)则较对照分别显著上升2.35倍和1.58倍.根系POD(过氧化物酶)和CAT(过氧化氢酶)活性、可溶性糖和可溶性蛋白含量在8mmol/L CuSO4处理下达到最高值后呈下降趋势.CuSO4浓度为15~20mmol/L时,根系APX活性和叶片光适应下PS II潜在最大光化学效率(Fv'/Fm'),以及幼苗全株鲜重、全株干重、地下部鲜重、地下部干重较对照显著下降.在非CuSO4胁迫条件下,基质中凹凸棒黏土的存在使得幼苗根系MDA含量较对照显著降低15.93%,但未对其它所测生理学指标产生显著影响;在20mmol/L CuSO4胁迫条件下,基质中凹凸棒黏土的存在使得幼苗根系和叶片中Cu2+含量分别显著下降30.78%和23.12%;同时显著缓解了20mmol/L CuSO4胁迫对根系活性氧水平、抗氧化酶活性、膜脂质过氧化程度、根尖膜损伤程度、可溶性蛋白和可溶性糖含量,叶片PS II光化学活性和叶绿素含量的不良影响,以及对幼苗生长的抑制作用.研究结果表明,培养基质中凹凸棒黏土的存在能够显著降低幼苗组织中Cu2+的生物有效性,继而缓解CuSO4胁迫对黄芪幼苗的生理学毒性作用.  相似文献   

11.
采用藻类生物测试标准方法研究了不同NO2--N初始浓度条件下铜绿微囊藻(Microcystis aeruginosa)的生长及生理变化.结果表明,相对BG11(NO2--N初始浓度为0)培养基,低初始NO2--N浓度(1,10mg/L)条件下铜绿微囊藻生长良好;高NO2--N初始浓度(20,30,40mg/L)条件下藻生长缓慢甚至停滞. NO2--N初始浓度由10mg/L到30mg/L,亚硝酸还原酶(NiR)活性和过氧化氢酶(CAT)活性呈增加趋势;在NO2--N初始浓度分别为20~30mg/L和20~40mg/L时,叶绿素a(Chl-a)含量和丙二醛(MDA)含量随NO2--N浓度增大而逐渐升高;在初始NO2--N浓度0,1,10,20,30mg/L条件下硝酸还原酶(NR)没有明显变化.这表明,铜绿微囊藻在NO2--N初始浓度10,20,30mg/L条件下能维持一定的生长,主要由于藻叶绿素含量的增加,NiR活性和防止细胞过氧化的酶CAT活性的提高所致.  相似文献   

12.
Salicylic acid (SA) was an essential component of the plant resistance to pathogens and also plays an important role in mediating plant response to some abiotic stress. The possible effects of SA on the growth and H2O2-metabolizing enzymes in rice seedlings under lead stress were studied. When rice seedlings grown in nutrient solution containing Pb^2+ (0, 0.05, 0.15, 0.25 mmol/L) for 18 d, the plant biomass as well as the chlorophyll content of leaves decreased with increasing Pb concentration. The pre-treatment with SA (treated with 0.1 mmol/L SA for 48 h before Pb stress) partially protected seedlings from Pb toxicity. The chlorophyll contents were significant higher in leaves of Pb-exposed with SA pre-treatment seedlings than in Pb-exposed plants at the same Pb intensity. SA pre-treated alone could significantly increase the length of shoot and root of seedlings but the vigour difference was not marked under long-term exposure to Pb toxicity. SA pre-treated influence the H2O2 level in leaves of seedlings by up-regulating the activity of superoxide dismutase (SOD), repressing the activity of catalase (CAT) and ascorbate peroxidase (APX) depending on the concentrations of Pb^2+ in the growth medium. The results supported the conclusion that SA played a positive role in rice seedlings against Pb toxicity.  相似文献   

13.
An outdoor experiment was set up to investigate the effects of used lubricating oil(5 L/m~2)on Aegiceras corniculatum Blanco. and Avicennia marina(Forsk)Vierh.,two salt-excreting mangroves.A.marina was more sensitive to used lubricating oil than A. corniculatum and canopy-oiling resulted in more direct physical damage and stronger lethal effects than base-oiling.When treated with canopy-oiling,half of A.corniculatum plants survived for the whole treatment time(90 d);but,for A.marina,high mortality (83%)resulted from canopy-oiling within 3 weeks and no plants survived for 80 d.Base-oiling had no lethal effects on A.corniculatum plants even at the termination of this experiment,but 83% of A.marina plants died 80 d after treatment.Forty days after canopy- oiling,93% ofA.corniculatum leaves fell and no live leaves remained on A.marina plants.By the end of the experiment,base-oiling treatment resulted in about 45% ofA.corniculatum leaves falling,while all A.marina leaves and buds were burned to die.Lubricating oil resulted in physiological damage to A.corniculatum leaves,including decreases in chlorophyll and carotenoid contents,nitrate reductase,peroxidase and superoxide dismutase activities,and increases in malonaldehyde contents.For both species,oil pollution significantly reduced leaf,root,and total biomass,but did not significantly affect stem biomass.Oil pollution resulted in damage to the xylem vessels of fine roots but not to those of mediate roots.  相似文献   

14.
渗滤液灌溉对香根草胁迫及抗氧化系统的影响   总被引:6,自引:0,他引:6       下载免费PDF全文
以香根草(Vetiveria zizanioids)和渗滤液循环出水为实验材料,比较了不同体积浓度渗滤液灌溉对香根草胁迫相关生理指标及抗氧化系统的影响.结果表明,与对照相比,小于35%浓度的渗滤液灌溉6个月降低了香根草叶片脯氨酸(Pro)含量和相对膜透性,提高了叶绿素、蛋白质、抗坏血酸(AsA)、还原型谷胱甘肽(GSH)含量和叶绿素a/b值,过氧化物酶(POD)和超氧化物岐化酶(SOD)被激活,丙二醛(MDA)含量被控制在较低的水平上,表明低浓度渗滤液灌溉有利于香根草生长.大于35%浓度的渗滤液灌溉,随浓度的增大,香根草叶绿素含量和a/b值明显降低,MDA、H2O2、Pro进一步积累,相对膜透性显著增加,AsA、GSH含量下降,SOD和POD活性受抑制,表明高浓度渗滤液灌溉会造成活性氧产生和抗氧化系统清除之间的失衡,导致膜脂过氧化作用加剧,会加重对香根草的胁迫.灌溉6个月较3个月相比,叶绿素含量下降,Pro、MDA积累,表明灌溉时间延长也会导致胁迫加重.  相似文献   

15.
苗期玉米、大豆在土壤-植物系统N2O排放中的贡献   总被引:5,自引:2,他引:3  
为区分植物在土壤-植物系统N2O排放中的贡献,用封闭式箱法对在温室内砂培和土培的玉米、大豆幼苗及砂、土、砂-植物系统、土壤-植物系统的N2O排放进行了测定,同时对植物N2O排放与植物叶片中的硝酸还原酶(NR)活性及NO3--N、NO2--N含量的关系进行了分析.结果表明:在53d的观测期内,玉米、大豆幼苗本身均可排放N2O,且在土壤(砂)-植物系统的N2O排放中占有很大份额(79.18%~100%);植物N2O的排放与植物叶片的硝酸还原酶活性和NO3--N、NO2--N的含量显著正相关(R2≥0.97,n=6).  相似文献   

16.
为了探讨施钼对不同浓度镉胁迫油菜的缓解效果,利用盆栽试验,研究了4种外源钼梯度(0、50、100、200 mg·kg-1)对低镉(0.5 mg·kg-1)和高镉(6.0 mg·kg-1)两种胁迫下油菜生理生化、生物量、镉的转运富集等的影响作用.结果显示,外源钼可促进镉胁迫油菜长度、鲜重、干重增加.不同浓度的钼可使镉胁迫油菜生理生化指标丙二醛(MDA)、脯氨酸(Pro)积累量显著降低,可溶性蛋白(SP)含量、可溶性糖(SS)含量、叶绿素(Chla和Chlb)含量、超氧化物歧化酶(SOD)活性和谷胱甘肽过氧化物酶(GPX)活性显著提高;同时,施入钼能够有效抑制油菜对镉的吸收富集,但对其转运影响相对较小,同时又可显著提高油菜对镉的耐性.钼对镉的抑制作用表现为提高油菜的生物量水平、改善其生理生化性能,通过参与油菜生理过程降低油菜对镉的吸收,进而提高油菜对进入体内镉的耐受力,外源钼能有效地降低Cd胁迫对油菜的毒害.  相似文献   

17.
为揭示Cd胁迫下外源脯氨酸对107杨(Populus×euramericana cv.‘74/76’)光合与叶绿素荧光特性的影响,以一年生107杨苗木为试验材料,采用盆栽控水试验,研究了添加不同浓度(0、10和20 mmol/L)外源脯氨酸对Cd(0、100、200和300 mg/kg)胁迫下107杨叶片光合气体交换参数、光响应参数和叶绿素荧光参数的影响.结果表明:①Cd作为独立因子可显著影响107杨叶片的光合气体交换参数、光响应参数和叶绿素荧光参数,外源脯氨酸作为独立因子对这些参数无显著影响,Cd与脯氨酸的交互作用对这3类参数均有显著影响.②随着w(Cd)的增加,107杨叶片净光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)和水分利用效率(WUE)的变化趋势基本一致,均显著下降,而胞间CO2浓度(Ci)呈显著上升趋势.与单独Cd处理组相比,在w(Cd)为200 mg/kg处理下,添加外源c(脯氨酸)为10 mmol/L时苗木叶片的Pn显著提高123.12%;WUE、PSⅡ原初反应最大量子效率(Fv/Fm)、实际光化学量子效率(φPSⅡ)、光化学淬灭系数(qP)和表观光合电子传递速率(ETR)分别显著提高43.73%、6.52%、27.99%、28.96%和63.26%;而非光化学淬灭系数(NPQ)显著降低19.97%.研究显示,w(Cd)低于200 mg/kg时,外源添加脯氨酸处理可增强107杨的PSⅡ光能转换效率和光强利用效率,防止过剩光能对光合机构的伤害,从而提高植株抗逆性与适应性,且以c(脯氨酸)为10 mmol/L时的处理效果较好.   相似文献   

18.
Cd胁迫对大豆各发育阶段生长及生理指标的影响   总被引:4,自引:0,他引:4       下载免费PDF全文
采用土壤盆栽试验方法,研究了不同浓度Cd胁迫下,大豆幼苗期、花荚期和成熟期植株的生长及叶片叶绿素含量、超氧化物歧化酶(SOD)活性、过氧化物酶(POD)活性和丙二醛(MDA)含量的变化.结果表明,大豆植株的生长在3个生长期均表现为低浓度Cd(£0.50mg/kg)下的刺激效应和高浓度Cd(31.00mg/kg)下的抑制效应;随着Cd胁迫浓度的累积,大豆生长整体上受到抑制.在幼苗期,大豆植株的叶绿素含量下降、SOD活性受到抑制、POD活性迅速激活,共同缓解Cd毒性;在花荚期,大豆植株的防御系统得到有效激发,保护性酶POD、SOD的活性急剧升高,叶绿素含量呈上升趋势;在成熟期,因为长时间的Cd毒害,尤其是Cd浓度较高的情况下,大豆植株的SOD、POD活性和叶绿素含量急剧下降.在Cd胁迫下,大豆植株的生长发育以及生理生化指标在大豆的3个生长期的变化模式差异显著,且大豆植株的生物量和株高与SOD活性在整个生长期均表现出显著的相关性.  相似文献   

19.
王美娥  周启星 《环境科学学报》2006,26(12):2033-2038
对Cd、Cu单因子处理下小麦幼苗叶片和根系的SOD、POD酶活、可溶性蛋白含量以及叶片中叶绿素含量的变化进行了研究.结果表明,Cd、Cu胁迫下,小麦幼苗受到损伤的明显症状之一是叶片叶绿素含量下降;小麦植株叶片POD、SOD酶活能够被诱导而升高;重金属Cd、Cu对小麦幼苗根系的损伤较叶片大;重金属对小麦幼苗的毒害机理之一是抑制了蛋白质的生物合成;重金属引起的各个生化指标随着处理浓度和处理时间的变化远比有机污染物(如豆磺隆)简单.  相似文献   

20.
为探讨NAP(萘)对金鱼藻的毒性及其机理,采用1/10Hoagland营养液水培法,研究了ρ(NAP)分别为1.25、2.5、5、10、20和40mg/L下金鱼藻中w(叶绿素)、w(可溶性蛋白)、w(GSH)(GSH为还原型谷胱甘肽)、MDA(丙二醛)含量及SOD(超氧化物歧化酶)和POD(过氧化物酶)活性的变化. 结果表明,在ρ(NAP)为1.25和2.5mg/L时,金鱼藻的各项生理活动与对照组基本没有显著差异(P>0.05). ρ(NAP)越高,对金鱼藻的毒性越大,当ρ(NAP)达40mg/L时,金鱼藻的生理活动受到显著影响(P<0.05). 在胁迫后期(第5、7天),随着ρ(NAP)的增加,w(叶绿素)、w(可溶性蛋白)以及SOD活性均有不同程度的下降,同时w(GSH)和MDA含量上升,膜脂过氧化加剧. 说明w(叶绿素)、MDA含量和SOD活性等是金鱼藻对萘胁迫较为敏感的参数,能表征萘胁迫的毒性.   相似文献   

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