Intraspecific differences in effects of co-contamination of cadmium and

A hydroponic experiment was carried out to study intraspecific differences in the effects of different concentrations of cadmium (Cd)(0-10 mg/L) and arsenate (As(V)) (0-8 mg/L) on the growth parameters and accumulation of Cd and As in six wheat varieties Jing-9428, Duokang-1, Jingdong-11, Jing-411, Jingdong-8 and Zhongmai-8. The endpoints of wheat seedlings, including seed germination,biomass, root length and shoot height, decreased with increasing the Cd and As concentrations. Significant differences in seed germination, biomass, root length, shoot height and the accumulation of Cd and As were observed between the treatments and among the varieties (p ＜ 0.05). The lethal dosage 50% were about 20, 80, 60, 60, 80 and 20 mg As/L for Jing-9428, Duokang-1, Jingdong-11,Jing-411, Jingdong-8 and Zhongmai-8, respectively, and the corresponding values for Cd were about 30, 80, 20, 40, 60 and 10 mg Cd/L, respectively. Among the six varieties, Duokang-1 was found to be the most resistant to Cd and As toxicity, and Zhongmai-8 was the most sensitive to Cd and As co-contamination. The resistance of the six varieties was found dependant on the seedling uptake of Cd and As. Duokang-1 was the most suitable for cultivation in Cd and As co-contaminated soils.     

磺胺间甲氧嘧啶-镉复合污染对作物种子发芽的影响

测定了黄潮土中常用兽药磺胺间甲氧嘧啶(SMM)与重金属镉(Cd)单一及复合污染对小麦和西红柿种子发芽(根伸长、芽伸长和发芽率)的影响,分析了土壤中药物浓度与作物生长抑制的剂量-效应关系及复合污染的毒性效应.结果表明,在单一污染物作用下,根伸长抑制率和芽伸长抑制率与药物浓度显著相关(P0.05);药物对根伸长及芽伸长的抑制高于对种子发芽的抑制;SMM对2种作物的毒性效应明显强于Cd,SMM对小麦和西红柿根伸长的IC50(抑制率为50%时污染物浓度)分别为33.7,49.3mg/kg,而Cd为507.3,599.8mg/kg.SMM和Cd复合污染时,在低Cd(200mg/kg)的胁迫下,联合作用主要体现为协同作用,但随着SMM浓度的增加,协同效应不显著(P>0.05);在高Cd(500mg/kg)作用下,二者的联合效应中Cd起主要作用.     

Joint toxicity of methamidophos and cadmium acting on Abelmoschus manihot

IntroductionNowadays, more and more ornamentals are being usedin families, parks, roads and other public sites with theimprovement of people’s living levels and changes in the citylife style (Wei, 2004; Zhou, 2004). At the same time,increas…     

不同浓度锌处理下水稻幼苗对镉的累积效应

为探究锌（Zn）对水稻镉（Cd）累积的影响及其根表铁膜所发挥的作用,选取Cd高累积型水稻品种中9优547（简称"Z547"）和Cd低累积型水稻品种金优402（简称"J402"）,采用温室水培试验,研究0、2、5、10、15和20 μmol/L等6个Zn浓度下水稻幼苗对Cd的累积效应,以及不同浓度Zn处理对根表铁膜生成量的影响.结果表明:①随着c（Zn）的增加,Z547和J402水稻幼苗生物量均呈先增后减的趋势,分别在c（Zn）为2和10 μmol/L时达到最大值.②Z547和J402水稻幼苗中w（Cd）均呈先降后增的趋势,分别在c（Zn）为5和2 μmol/L时达到最小值;当水稻幼苗中w（Cd）达到最小值时,Z547根和地上部中w（Cd）分别为31.65和11.47 mg/kg,J402根和地上部中w（Cd）分别为22.58和14.36 mg/kg.③不同浓度Zn处理下水稻幼苗各部位中w（Cd）均与根表铁膜中w（Mn）、w（Fe）、w（Fe+Mn）呈显著正相关,高铁膜处理水稻幼苗中w（Cd）显著高于低铁膜处理,表明根表铁膜生成量的增加会促进Cd在水稻幼苗中的累积.研究显示,当c（Zn）较低时,c（Zn）的增加会抑制水稻幼苗对Cd的累积;当c（Zn）较高时,c（Zn）的增加会促进水稻幼苗对Cd的累积,而Zn可通过控制根表铁膜的生成来影响水稻幼苗对Cd的累积.      

水培条件下秋华柳对重金属Cd的富集特性及光合响应

采用水培试验的方法,研究了不同Cd胁迫浓度〔ρ(Cd2+)分别为0、1、5、10和20 mg/L〕下秋华柳的生长、光合耐性及其对Cd的富集特性和转移能力.结果表明:①随着Cd胁迫浓度的升高,秋华柳生长所受到的抑制程度有所增加.除20 mg/L处理组外,其余各处理组的耐性指数(TI)均大于70,表现出较高的耐性.②低Cd胁迫浓度(1 mg/L)下秋华柳具有较好的光合耐性,当Cd胁迫浓度达到20 mg/L时,秋华柳的光合系统才受到明显影响.③秋华柳对外源Cd的富集能力较强,随着Cd胁迫浓度的升高,秋华柳所积累的Cd显著增加且主要积累于根部,表现为叶<茎<根.当Cd胁迫浓度小于5 mg/L时,秋华柳根部吸收的Cd向地上部分转移的效果较好.试验显示,秋华柳对于较低Cd胁迫浓度(≤10 mg/L)具有较好的耐受性和富集能力,可用于三峡库区消落带表层土壤Cd污染严重区域进行植物修复.      

微塑料与Cd交互作用对小麦种子发芽的生态毒性研究

为探究微塑料、重金属以及二者的交互作用对农作物种子生长特性的影响,选取小麦(Triticum aestivum L)为实验对象,开展土壤中微塑料聚乙烯(mPE)和聚丙烯(mPP)(0,10,50,100,200,500,1000,5000和10000mg/kg)与重金属镉(Cd)(0,1和5mg/kg)单一及复合污染对...     

土壤镉暴露对玉米和大豆的生态毒性评估

以中国东北黑土为培养基,通过室内急性毒性实验,采用Trimmed Spearman-Karber方法计算EC50值(半抑制浓度),并分析作物的生物累积系数(BAF),定量化评估了土壤中镉对玉米和大豆的生态毒性及生物有效性.测量终点为种子发芽率、根长和幼茎长.结果表明,土壤镉暴露给农作物带来一定的负生长效应.种子发芽率不是评估土壤镉生态毒性的敏感因子,根生长是敏感的毒性测量终点.镉在植株体内的累积及迁移与作物种类和土壤镉浓度有关.玉米植株体内累积了较大量的镉,而大豆植株体内镉由根向幼茎的迁移较为显著.     

Uptake and accumulation of copper by roots and shoots of maize(Zea may L.)

The effects of different concentrations of copper sulfate on rootand shoot growth of maize(Zea mays L.) and the uptake and accumulation of Cu2+ by its roots and shoots were investigated in the present study. The concentrations of opper sulfate (CuSO4.5H2O) used were in the range of 10-5-10-3mol/L. Root growth decreased progressively with increasing concentration of Cu2+ in solution. The seedlings exposed to 10-3 mol/L Cu exhibited substantial growth reduction, yielding only 68% of the root length of the control. The shoot growth of the seedlings grown at 10-5-10-4 mol/L Cu2+ were more or less than the same as the control seedlings. The leaves treated with 10-3 mol/L Cu2+ were obviously inhibited in shoot growth. The fresh and dry weights both in roots and shots decreased progressively with increasing Cu2+ concentration.This fits well with the above mentioned effects of copper sulfate on root growth. Zea mays has considerable ability to remove Cu from solutions and accumulate it. The Cu content in roots of Z. Mays increased with increasing solution concentration of Cu2+. The amount of Cu in roots of plants treated with 10-3, 10-4 and 10-5 mol/L Cu2+ were 10, 8 and 1.5 fold, respectively, greater than that of roots of control plant. However, the plants transported and concentrated only a small amount of Cu in their shoots.     

Uptake and accumulation of copper by roots and shoots of maize (Zea mays L.)

ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅｃｏｎｔｅｎｔｏｆＣｕｉｎｔｈｅｅｎｖｉｒｏｎｍｅｎｔｉｓｕｓｕａｌｌｙ20ｔｏ30ｐｐｍｉｎｎｏｎｃｏｎｔａｍｉｎａｔｅｄｓｏｉｌ(Ｎｒｉａｇｕ,1979;Ｓａｌｏｍｏｎｓ,1984),ｂｕｔｉｓｍｏｒｅｔｈａｎ2000ｐｐｍｉｎｍｉｎｉｎｇａｒｅａｓａｎｄｉｎｔｈｅｖｉｃｉｎｉｔｙｏｆｓｍｅｌｔｅｒｓ(Ｆｒｅｅｄｍａｎ,1980;Ｈｕｍｐｈｒｅｙｓ,1984).ＩｔｈａｓｂｅｅｎｄｅｍｏｎｓｔｒａｔｅｄｔｈａｔｃｏｐｐｅｒｓｏｌｕｂｉｌｉｔｙｄｅｐｅｎｄｓｏｎｐＨｉｎｓｏｉｌｓ,ａｎｄｉｔｉｓｏｂ…     

Ability of Agrogyron elongatum to accumulate the single metal of cadmium, copper, nickel and lead and root exudation of organic acids

ＩｎｔｒｏｄｕｃｔｉｏｎＣｏｎｔａｍｉｎａｔｉｏｎｏｆｓｏｉｌｓｗｉｔｈｈｅａｖｙｍｅｔａｌｓｂｅｃｏｍｅｓａｎｉｎｃｒｅａｓｉｎｇｐｒｏｂｌｅｍｉｎｍａｎｙｃｏｕｎｔｒｉｅｓａｌｌｏｖｅｒｔｈｅｗｏｒｌｄ .Ｔｈｉｓｉｓｍｕｃｈｃｏｎｃｅｒｎｅｄｂｅｃａｕｓｅｏｆｔｈｅｉｒｅａｓｙｔｒａｎｓｆｅｒｒｉｎｇｆｒｏｍｓｏｉｌｓｔｏｐｌａｎｔｓ ,ｅｖｅｎｔｏａｎｉｍａｌｓａｎｄｈｕｍａｎｂｅｉｎｇｓ .Ｉｎｍｏｓｔｃａｓｅｓ,ｐｌａｎｔｓｇｒｏｗｎｉｎｈｅａｖｙｍｅｔａｌ ｐｏｌｌｕｔｅｄｓｏｉｌｓｓｈｏ…     

钒镉复合污染对水稻吸收积累镉、钒和磷的影响

采用溶液培养法研究钒与镉复合污染对水稻生长及其吸收积累镉的影响,以便弄清在钒与镉复合污染条件下水稻的生长情况.试验结果表明,钒镉复合污染可影响水稻的生长发育.在培养液镉浓度(1 0mg·L-1)不变的情况下,随着溶液中钒浓度的增加,水稻根长、根系和茎叶的干重不断减少.当溶液中钒浓度达到1 6mg·L-1和3 2mg·L-1时,水稻茎叶和根系干重减少分别达到显著水平(p<0 05).钒镉复合污染也影响水稻植株对磷、钒和镉的吸收与积累.当培养液中镉浓度不变时,随着溶液中钒浓度的增加,水稻根系和茎叶中的磷浓度不断降低,而钒含量却不断提高,根系比茎叶积累更多的钒.此外,钒可抑制水稻植株对镉的吸收与积累.     

菌渣中青霉素对蔬菜种子萌发的生态毒性效应

为推动青霉素菌渣环境安全利用技术规范的建立,以油麦菜、油菜、白菜和生菜4种蔬菜为研究对象,以种子发芽率、幼苗鲜质量、芽长和根长为毒性敏感指标,研究了不同处理组〔ρ（PG）分别为10、100、200、400、800、1 200、1 600、2 000、2 400、3 200和4 000 mg/L〕和对照组的青霉素（Penicillin,简称“PG”）对4种蔬菜种子萌发的生态毒性响应关系.结果表明:①与对照组相比,各处理组4种蔬菜种子发芽率之间均无显著性差异（P>0.05）;当ρ（PG）≥1 200 mg/L时,油菜种子的芽长增长率在60%左右,且与对照组相比具有显著差异（P < 0.05）;在ρ（PG）为200 mg/L时,生菜鲜质量达到最大值（0.29 g）,较对照组增加了10.37%,白菜鲜质量在ρ（PG）为400 mg/L时达到最大值,较对照组增加了5.76%,而在试验浓度范围内,各处理组4种蔬菜种子的根长均随着ρ（PG）的增大表现出逐渐增强的抑制作用.②PG对4种蔬菜的根长抑制率剂量-效应关系均符合Allometric模型,即y=axb〔其中,x为ρ（PG）,y为根长抑制率,a和b均为常数〕.③油麦菜、油菜、白菜和生菜4种蔬菜对PG的根长半抑制浓度（IC₅₀）分别为1 675.11、995.67、3 736.40和2 510.24 mg/L,4种蔬菜根长抑制率对PG的敏感程度表现为油菜>油麦菜>生菜>白菜（P < 0.05）.研究显示,与油麦菜、白菜和生菜相比,油菜更适合作为PG的生态毒性指示植物.      

旺盛期烟草对镉富集敏感性研究

采用盆栽试验方法,揭示了旺盛期烟草（云烟99）对镉的富集特点以及光合等生理指标对镉胁迫的响应.结果表明：当土壤镉含量分别为4.43,7.94,17.33和49.79mg/kg时,烟草茎、叶及地上部镉的富集系数（植物镉含量与土壤镉含量的比值）均大于1,转移系数（地上部镉含量与根镉含量的比值）也大于1,但镉含量未达到镉超富集植物的临界含量标准100mg/kg.当土壤镉含量为4.43mg/kg时,烟草的耐性较强.当土壤镉含量大于7.94mg/kg时,烟草的生物量、叶片光合色素含量、净光合速率、蒸腾速率、气孔导度和SOD活性均显著下降（P<0.05）,胞间CO₂浓度和MDA含量显著提高（P<0.05）.旺盛期烟草对镉富集比较敏感,建议烟草的种植要远离镉污染土壤或镉背景值较高的土壤.     

作物幼苗Cd含量标征土壤Cd污染的研究

用盆栽试验,以小麦、大豆和油菜为对象,研究了利用作物幼苗Ｃｄ含量标征土壤Ｃｄ污染的可行性。结果表明,在３种作物生长过程中,幼苗Ｃｄ含量均高于生长后期或可食部分Ｃｄ含量。小麦、大豆籽粒Ｃｄ含量与苗期Ｃｄ含量及土壤Ｃｄ投加量成正相关关系,采收期油菜Ｃｄ含量与苗期Ｃｄ含量成正相关关系。这３种作物的可食部分Ｃｄ含量达到我国食品卫生标准时,小麦三叶期、大豆幼苗地上部分及油菜幼苗的Ｃｄ含量临界值分别为０．７２     

废塑料再生产品对生菜种子萌发及根伸长影响

通过室内培养试验研究了三种废塑料再生产品对生菜种子萌发及根伸长的影响。结果表明:在生菜种子发芽阶段,再生塑料和再生建材对生菜种子发芽率影响都不大,但低浓度的再生油就已对生菜种子发芽率产生了很大的抑制效应,如500mg/kg处理时,发芽率为对照的61.5%,极显著地低于对照(P0.01)。在生菜生长阶段,随着废塑料再生产品处理浓度的增加,对生菜根长和芽长的抑制作用都呈上升趋势。其中,再生塑料和再生建材对生菜种子发芽率及根、芽长受抑制的敏感性依次为根长芽长发芽率,而对于再生油,根、芽长受污染胁迫抑制明显,当污染浓度为15000mg/kg时,根长抑制率已达到了67.1%±2.1%,芽长抑制率高达77.8%±2.2%,三项指标对再生油胁迫的敏感性则表现为发芽率芽长根长。     

纳米银与镉的复合毒性对拟南芥根系形态及叶片生理指标的影响

为研究纳米银（AgNPs）与镉（Cd²⁺）对拟南芥的复合毒性,本文以不同浓度的PVP coated-AgNPs和Cd²⁺处理拟南芥幼苗一周后,测定了拟南芥幼苗主根长度,根毛数量,叶片中光合色素和可溶性蛋白含量及抗氧化系统相关酶活性.结果表明,高浓度（5mg/L） Cd²⁺能显著抑制根长,提高可溶性蛋白含量及SOD（超氧化物歧化酶）和POD（过氧化物酶）的活性.在高浓度Cd²⁺（5mg/L）中加入AgNPs能显著增强Cd²⁺对根长的抑制作用,而高浓度的Cd²⁺能缓解AgNPs对根毛的抑制作用;在低浓度Cd²⁺（0.1mg/L和1mg/L）中加入AgNPs能显著增强Cd²⁺对色素含量抑制作用;在含有Cd²⁺的处理中,SOD和POD在1mg/L AgNPs下活性最高;以上结果说明Cd²⁺和AgNPs对拟南芥幼苗根系形态及叶片生理指标都存在交互影响.     

土霉素对小麦种子发芽与幼苗生长发育的生态毒性

研究了土霉素对小麦种子发芽以及早期幼苗生长发育的生态毒性效应.结果表明,土霉素对小麦种子芽长及根长的抑制效应显著(p<0.01),而且它们之间具有良好的剂量-效应关系.根据线性回归方程得出土霉素对小麦种子芽长和根长的半抑制浓度为65.5 mg/L和34.7 mg/L.然而,土霉素对小麦种子的发芽率并没有显著的影响.研究还表明,0.15~2.4 mg/L土霉素暴露21 d后,小麦叶片中的叶绿素含量降低了35.6%~47.3%,叶片及根部的可溶性蛋白含量也均呈显著下降趋势.暴露7 d后,0.15~2.4 mg/L土霉素对小麦叶片和根部SOD与POD活性的抑制效应不显著,但随着暴露时间的延长,土霉素对小麦的SOD与POD酶活性抑制率显著下降;2.4 mg/L土霉素暴露21 d后,小麦根部的SOD活性下降72.3%,说明土霉素对小麦幼苗体内的抗氧化系统具有破坏作用.该实验结果显示,低浓度土霉素长期暴露对小麦幼苗的生长发育具有不良的生态毒性效应.     

不同pH条件下CdCl2对紫花苜蓿种子萌发的胁迫效应

采用培养皿滤纸萌发试验,研究在3种pH(4.0、6.0和8.0)条件下,不同质量浓度(0、5、10、20、40和80mg/L)的CdCl₂溶液对紫花苜蓿种子萌发的胁迫效应. 结果表明,低质量浓度的CdCl₂(≤20mg/L)显著提高了紫花苜蓿种子的发芽率、发芽势、发芽指数和活力指数,ρ(CdCl₂)为20mg/L、pH为6.0时活力指数与对照组相比明显增加,达到177.52±16.61;随着ρ(CdCl₂)的提高,CdCl₂对苜蓿幼苗生长的促进效应不断增强,ρ(CdCl₂)为20mg/L时,3种pH条件下的芽鲜质量分别为(6.60±0.11)、(6.68±0.20)和(9.51±0.16)mg,根鲜质量分别为(6.71±0.10)、(7.09±0.08)和(9.10±0.08)mg,达到最大; 当ρ(CdCl₂)达到40和80mg/L时,紫花苜蓿种子萌发和幼苗生长则受到显著抑制,ρ(CdCl₂)为80mg/L时发芽率和活力指数分别仅为对照组的14.8%和46.5%;ρ(CdCl₂)为80mg/L时芽鲜质量最低,3种pH条件下分别为(3.48±0.15)、(4.03±0.19)和(7.00±0.22)mg. 研究还发现,紫花苜蓿种子发芽率和活力指数随pH降低而降低,弱碱(pH=8.0)条件下紫花苜蓿在ρ(CdCl₂)为80mg/L时的发芽率为66.40%±3.19%,大于酸性条件(pH=4.0、6.0)下的发芽率(11.20%±3.61%、9.20%±4.22%),而活力指数(93.90±10.71)也高于酸性条件(pH=4.0、6.0)下的活力指数(49.77±3.25、56.67±3.48),表明pH由酸性到碱性的变化过程能够缓解CdCl₂对紫花苜蓿种子萌发和幼苗生长的毒性.      

不同作物种苗对水中重金属镉去除的比较研究

以玉米、向日葵和蓖麻为实验材料,研究了3种作物种苗对镉的去除效果以及种苗生理生化指标的变化情况.结果表明,①随着处理时间的延长,溶液中镉含量逐渐降低,去除过程主要集中在前48 h.在1 mg·L^-1和2 mg·L^-1 Cd溶液中,向日葵和蓖麻种苗的去除效果要好于玉米种苗的;而在5 mg·L^-1和10 mg·L^-1 Cd溶液中,去除效果顺序为：蓖麻>玉米>向日葵.②种苗从溶液中吸收的镉绝大部分集中在根部.3种作物种苗对镉的富集能力大小顺序为：向日葵>蓖麻>玉米.③在不同镉处理浓度下,3种作物种苗的叶片质膜透性、根系活力、叶绿素含量和游离脯氨酸含量等生理生化指标均有不同程度的变化.向日葵的根系活力和脯氨酸含量均与镉积累量呈现显著相关性;蓖麻叶片的质膜透性和脯氨酸含量均与镉含量呈现显著正相关.3种作物种苗对镉都有一定的耐受性,而向日葵和蓖麻种苗的耐受性比玉米种苗的强.     

Effects of arsenic on seed germination and physiological activities in wheat seedlings

The effects of arsenic(As)were investigated on seed germination,root and shoot length and their biomass and some other factors to elucidate the toxicity of As.The results showed low concentrations of As(O-1 mg/kg)stimulated seed germination and the growth of root and shoot,however,these factors all decreased gradually at high concentrations of As(5-20 mg/kg).The contents Of O2-,MDA,soluble protein and peroxidase(POD)activity all increased with increasing As concentrations.Soluble sugar content,ascorbate peroxidase(APX),and superoxide dismutase(SOD)activities decreased at low concentrations of As,and increased at high concentrations of As.While acetylsalicylic acid(ASA)and chlorophyll contents,catalase(CAT)activity displayed increasing trend when the concentrations of As was lower than 1 mg/kg,and then decreasing trend.By polyacrylamide gel electrophoresis(PAGE).As induced the expression of POD isozymes of wheat seedlings.As induced the expression of CAT isozymes but inhibited the expression of SOD isozymes of wheat seedlings at concentrations lower than 1 mg/kg.However,As inhibited the expression of CAT isozymes but induced the expression of SOD isozymes at concentrations higher than 5 mg/kg.The results indicated As could exert harmfulness in the early development stage of wheat at inappropriate concentrations.