重金属在海州香薷和鸭跖草叶片提取物中的分配

海州香薷 (Ｅｌｓｈｏｌｔｚｉａｈａｉｃｈｏｗｅｎｓｉｓ)和鸭跖草 (Ｃｏｍｍｅｌｉｎａｃｏｍｍｕｎｉｓ)是我国长江中下游地区废铜矿石堆上最常见的两种优势植物 ,都能不同程度地富集铜 ,尤其是鸭跖草 ,铜的含量可达到超积累水平 (超过 5 0 0ｍｇ·ｋｇ-1ＤＷ)。但它们积累     

功能内生菌强化超积累植物修复重金属污染土壤的研究进展

土壤重金属污染已成为威胁人类健康和经济可持续发展的重大环境问题。内生菌-超积累植物联合修复是近年来发展起来的一种重金属污染土壤的生物修复技术,不仅能促进植物生长、提高其重金属抗性,同时,还可以改变重金属的形态和迁移率,提高植物修复的效率,具有广阔的应用前景。现概述植物内生菌(plant growth promoting endophyte, PGPE)的特征、种类以及促进超积累植物生长的作用机理,综述近年来国内外有关功能内生菌协同超积累植物修复重金属污染土壤的应用现状和研究进展,同时展望内生菌协同超积累植物修复土壤重金属的研究思路,旨在为今后土壤重金属污染治理提供新的思路和理论依据。     

重金属污染土壤的植物修复技术

土壤受重金属污染的状况在国内外都相当严重,传统的重金属污染土壤的修复技术存在许多难以克服的缺陷;近年来,一种运用植物来去除有毒重金属的新兴修复技术(植物修复技术)给这一问题提供了良好的解决途径,该技术被认为是一种低成本有效的“绿色”技术.但其主要缺点是修复周期较长,筛选、培育超积累植物以及提高土壤中重金属的生物有效性是提高植物吸收效果、缩短修复周期的关键.本文就超积累植物的筛选、转基因超积累植物及螯合剂强化植物吸收等热点问题的研究进展作了介绍,并对我国当前植物修复技术研究工作的重点提出了建议.     

新台糖22号甘蔗的快速繁殖

1　植物名称　甘蔗 (Ｓａｃｃｈａｒｕｍｏｆｆｉｃｉ ｎａｒｕｍ)新台糖 2 2号。2　材料类别　顶芽、腋芽。3　培养条件　 ( 1 )分化培养基 :ＭＳ 6 ＢＡ1 .5ｍｇ·Ｌ-1(单位下同 ) ＮＡＡ 0·2 ;( 2 )继代培养基 :ＭＳ 6 ＢＡ 1 .0 ＮＡＡ 0 .1 ;( 3)生根培养基 :1 / 2     

土壤Hg污染及修复技术研究

早在 2 0世纪 6 0年代初期 ,日本查明了“水俣病”[1] 是由甲基Ｈｇ污染造成的 ,引起世界范围内人们对Ｈｇ污染危害的重视 ,使其研究日益增多。Ｈｇ通过不同途径进入土壤环境 ,土壤中的Ｈｇ经过复杂的物理、化学反应 ,大部分以各种形态滞留在土壤中 ,同时Ｈｇ在作物可食部分积累并进入食物链循环 ,对人体健康构成威胁。我国被Ｈｇ污染的耕地面积有 3.2× 10 4 ｈａ ,每年产生污染环境的Ｈｇ达 1.9× 10 8ｋｇ[2 ] 。土壤一旦遭受Ｈｇ污染 ,对人类健康构成潜在的危害 ,因此土壤Ｈｇ污染的治理及生物修复技术研究应运而生。重金属污染治理的传…     

植物超积累重金属的生理机制研究进展

土壤重金属污染已经成为一个全球性问题。重金属超积累植物在修复土壤重金属污染中具有重要的应用前景。重金属超积累植物通常具备三个基本特征,即：根系具有从土壤中吸收重金属的强大能力、能从根到地上部分高效转运重金属、在叶片中能解毒和隔离大量重金属。本文总结了重金属超积累植物吸收、转运、隔离和解毒重金属的生理机制研究进展,以期为进一步阐明植物超积累重金属的机制及其在植物修复中的应用提供参考。     

超积累植物与丛枝菌根真菌共生及其联合吸收积累重金属的效应

利用超积累植物进行重金属污染土壤修复是应对全球大面积分布无机污染问题的重要解决方法之一。超积累植物虽然具有超量积累重金属的能力,但其定植、生长和提取功能的发挥都受到重金属胁迫的显著影响。利用丛枝菌根真菌 (Arbuscular mycorrhizal fungi,AMF) 强化超积累植物功能可联合发挥二者的功能优势,提升修复效率、缩短修复周期、保持修复效果的稳定性和长期性,在日益复杂、严峻的重金属污染治理领域具有重要的研究价值和广阔的应用前景。文中首先给出了超积累植物的概念、中国本土首次报道的典型重金属元素超积累植物和能与AMF形成共生体系的超积累植物名录,系统深入地探讨了AMF对超积累植物生长和吸收累积重金属的影响,以及超积累植物+AMF联合吸收积累重金属的效应与作用机制,认为AMF可通过调节根围理化与生物条件、元素平衡状况、生理代谢和基因表达等途径,增强超积累植物吸收积累重金属的效应,超积累植物+AMF构建的共生体系具备联合修复重金属污染生境的潜力。最后指出了超积累植物+AMF共生联合修复技术当前面临的关键问题、发展方向和应用前景。     

低放核素污染土-水介质的植物修复研究进展

植物修复技术是利用植物根系吸收水分和养分的过程来吸收和转化土壤和水体中的污染物,以期达到清除,修复和治理的目的,是用于对土壤-水体中重金属和放射性核素污染清除的生态技术.本文就放射性核素的来源、污染现状、植物对放射性核素的积累筛选以及对污染土壤的修复研究进行综述,以明确植物修复技术在改善环境中的作用,为进一步筛选超积累植物并探讨植物对放射性核素污染的修复机理提供参考.     

植物修复——治理土壤重金属污染的新途径

介绍了重金属污染土壤的植物修复的概念、原理与研究动态以及重金属超积累植物的特性 ,及其在治理污染土壤中的潜力 ,为土壤重金属污染的整治及其生态的修复提出新途径。     

野牡丹和地稔的组织培养及植株再生

1　植物名称　野牡丹 (Ｍｅｌａｓｔｏｍａｃａｎｄｉｄｕｍ) ,地稔 (Ｍ .ｄｏｄｅｃａｎｄｒｕｍ)。2　材料类别　野外生长的幼嫩茎尖或腋芽。3　培养条件　外植体经 70 %酒精和 0 .1 %升汞消毒以及无菌水清洗后 ,切取生长点部位 ,将其接种于ＭＳ培养基上培养。培养温度 (2 5± 2 )℃ ,光照时间 1 0ｈ·ｄ-1,光照度1 1 0 0ｌｘ。培养基含蔗糖 2 % ,琼脂 0 .6 % ,ｐ5 .8。其中繁殖培养基含 1 .0ｍｇ·Ｌ-1ＢＡ和0 .1ｍｇ·Ｌ-1ＮＡＡ ,生根培养基含 0 .1ｍｇ·Ｌ-1ＩＢＡ。4　生长与分化情况　　嫩芽在繁殖培养基上培养 ,1周内即长出黄绿色…     

Submergence-Induced Ethylene Synthesis,Entrapment, and Growth in Two Plant Species with Contrasting Flooding Resistances

Submergence-induced ethylene synthesis and entrapment were studied in two contrasting Rumex species, one flood-resistant (Rumex palustris) and the other flood-sensitive (Rumex acetosa). The application of a photoacoustic method to determine internal ethylene concentrations in submerged plants is discussed. A comparison with an older technique (vacuum extraction) is described. For the first time ethylene production before, during, and after submergence and the endogenous concentration during submergence were continuously measured on a single intact plant without physical perturbation. Both Rumex species were characterized by enhanced ethylene concentrations in the shoot after 24 h of submergence. This was not related to enhanced synthesis but to continued production and physical entrapment. In R. palustris, high endogenous ethylene levels correlated with enhanced petiole and lamina elongation. No dramatic change in leaf growth rate was observed in submerged R. acetosa shoots. After desubmergence both species showed an increase in ethylene production, the response being more pronounced in R. palustris. This increase was linked to the enhanced postsubmergence growth rate of leaves of R. palustris. Due to the very rapid escape of ethylene out of desubmerged plants to the atmosphere (90% disappeared within 1 min), substantial underestimation of internal ethylene concentrations can be expected using more conventional vacuum extraction techniques.     

Ethylene Sensitivity and Response Sensor Expression in Petioles of Rumex Species at Low O2 and High CO2 Concentrations

Rumex palustris, a flooding-tolerant plant, elongates its petioles in response to complete submergence. This response can be partly mimicked by enhanced ethylene levels and low O2 concentrations. High levels of CO2 do not markedly affect petiole elongation in R. palustris. Experiments with ethylene synthesis and action inhibitors demonstrate that treatment with low O2 concentrations enhances petiole extension by shifting sensitivity to ethylene without changing the rate of ethylene production. The expression level of the R. palustris gene coding for the putative ethylene receptor (RP-ERS1) is up-regulated by 3% O2 and increases after 20 min of exposure to a low concentration of O2, thus preceding the first significant increase in elongation observable after 40 to 50 min. In the flooding-sensitive species Rumex acetosa, submergence results in a different response pattern: petiole growth of the submerged plants is the same as for control plants. Exposure of R. acetosa to enhanced ethylene levels strongly inhibits petiole growth. This inhibitory effect of ethylene on R. acetosa can be reduced by both low levels of O2 and/or high concentrations of CO2.     

铜和模拟酸雨复合胁迫对酸模铜富集、生长及抗氧化酶系统的影响

采用盆栽方法,研究了Cu(0～1500 mg·kg^-1)和酸雨(pH 2.5～5.6)复合胁迫对酸模Cu富集、生长和抗氧化酶系统的影响.结果表明：酸模根和地上部Cu的积累量随土壤Cu浓度增大而增加,且根>茎叶,酸雨能促进酸模对Cu的吸收;随着土壤中Cu浓度和酸雨强度的增加,酸模的生物量逐渐下降,根和叶中MDA含量增加,且与Cu处理浓度显著正相关,根和叶中SOD和POD活性则均呈先上升后下降的趋势.酸模对Cu和酸雨有很强的耐受能力,在酸雨地区Cu污染土壤修复中具有很好的应用潜力.     

Growth responses of Rumex species in relation to submergence and ethylene

Abstract. Submergence stimulates growth of the petioles of Rumex palustris and Rumex crispus under field, greenhouse and laboratory conditions. Growth of Rumex acetosa petioles was hardly influenced by submergence. These growth responses under flooded conditions can be partially mimicked by exposing non-submerged Rumex plants to ethylene-air mixtures. Submergence of intact plants in a solution of AgNO₃ inhibited the elongation of all petioles of R. palustris and the youngest petiole of R. crispus and stimulated growth of the youngest petiole of R. acetosa , The ethylene-air mixture experiments, the effect of AgNO₃ and observed increase of the endogenous ethylene concentration during submergence suggest that ethylene plays a regulatory role in the growth responses of these Rumex species under submerged conditions. The three Rumex species showed a gradient in elongation responses to submergence, which correlates with the field distribution of the three species in a flooding gradient.     

The uptake of copper by plants dominantly growing on copper mining spoils along the Yangtze River,the People's Republic of China

Elsholtzia haichowensis Sun., Commelina communis Linn., and Rumex acetosa Linn. are the dominant species that vastly grow over the copper mining spoil heaps and copper-contaminated soil of the areas along the middle and lower streams of the Yangtze River. Each has its own ecological habits. Chemical analytical data show that these plants can accumulate copper to various extents, depending on the copper content of the supporting soils and plant species. The highest concentration copper was found in R. acetosa with the leaf copper concentration ranging from 340 to 1102 mg/kg and averaging 601 mg/kg (dry weight basis). C. communis also contained high copper concentration in its leaves ranging from 19 to 587 mg/kg and averaging 157 mg/kg. E. haichowensis has the lowest copper concentration in its leaves from 18 to 391 mg/kg and averaging 102 mg/kg. The copper content of the soils supporting all the species varies to a great extent from place to place. All these lines of evidence suggest that E. haichowensis, C. communis, and R. acetosa can serve as pioneer species for reclamation of copper mined land and can be used as model plants for investigation of plant tolerance mechanisms, and geochemical prospecting. This revised version was published online in June 2006 with corrections to the Cover Date.     

Contrasting interactions between ethylene and abscisic acid in Rumex species differing in submergence tolerance

Complete submergence of flooding-tolerant Rumex palustris plants strongly stimulates petiole elongation. This escape response is initiated by the accumulation of ethylene inside the submerged tissue. In contrast, petioles of flooding-intolerant Rumex acetosa do not increase their elongation rate under water even though ethylene also accumulates when they are submerged. Abscisic acid (ABA) was found to be a negative regulator of enhanced petiole growth in both species. In R. palustris, accumulated ethylene stimulated elongation by inhibiting biosynthesis of ABA via a reduction of RpNCED expression and enhancing degradation of ABA to phaseic acid. Externally applied ABA inhibited petiole elongation and prevented the upregulation of gibberellin A(1) normally found in submerged R. palustris. In R. acetosa submergence did not stimulate petiole elongation nor did it depress levels of ABA. However, if ABA concentrations in R. acetosa were first artificially reduced, submergence (but not ethylene) was then able to enhance petiole elongation strongly. This result suggests that in Rumex a decrease in ABA is a prerequisite for ethylene and other stimuli to promote elongation.     

A genetic method to resolve gender complements investigations on sex ratios in Rumex acetosa

The perennial dioecious weed, Rumex acetosa, possesses sex chromosomes (XX in females, XY1Y2 in males). Yet, the operational sex ratios are female-biased. Until now, sex ratio studies in R. acetosa, as in most plants, have relied on data obtained at sexual maturity. To resolve gender among the seeds and nonflowering plants of R. acetosa, a genetic method involving a DNA marker located on both Y chromosomes has now been developed and applied. The results suggest that the sex ratios are about 1 : 1 in the whole seed pool, but that a significant female bias develops by the time of flowering. Since the age of sexually mature plants is two years or more, the time frame during which the female bias present at sexual maturity develops can be several years. It appears that male seeds germinate at a lower rate and males suffer from a greater mortality during the years-long lifespan of R. acetosa. However, there are no considerable sex-related differences in vegetative vigour.     

Variation in tissue element concentration in mire plants over a range of sites

Elements in surface peat and ground water were estimated on seven mire sites in central and north Sweden. The variation in tissue clement concentration was studied in eleven plants occurring on the studied sites. The elements estimated were: N, P, K. Ca, Mg, Fe, Mn, Zn, Al, Cu, Mo, Na, S, B, and Si. The species studied were; Carex diandra, Carex limosa, Carex rostrata, Epilobium palustre, Menyanthes trifoliate, Pedicularis palustris, Rumex acetosa, Saxifraga hirculus, Scirpus hudsonianus, Stellaria crassifolia and Tofteldia pusilla . In surface peat over the range of sites, the variation in total concentrations of nitrogen and phosphorus was six and tenfold, respectively. The variation in total concentration of potassium was four-fold. Extractable concentrations of these three elements showed an even greater variation between sites. Over the range of sites, the variation in tissue element concentration was larger in roots than in above-ground parls. In above-ground parts, floral parts varied less in tissue element concentration than did stems and leaves. The largest variation in tissue element concentration was found in Carex rostrata and Menyanthes trifoliata . The smallest variation was found in Saxifraga hirculus . Tissues of the rich fen species Saxifraga hirculus and Stellaria crassifolia had the lowest concentrations of heavy metals. The correlation between substrate element concentration and tissue concentration differed both between tissues and species. Concentrations of N, P and K in tissues of the Carex species were highly correlated with the concentrations of these elements in the substrate, while N, P and K concentrations in tissues of the herbaceous species, especially Saxifraga hirculus . correlated less well.     

土壤重金属污染对蚯蚓的急性毒性效应研究

测定了草甸棕壤条件下 ,Cu、Zn、Pb、Cd单一 /复合污染对蚯蚓的急性致死及亚致死效应 .结果表明 ,Cu、Pb浓度与蚯蚓死亡率显著相关 (α=0 .0 5 ,RCu=0 .86 ,RPb=0 .87) ,Cu浓度与生长抑制率显著相关 (α=0 .0 5 ,RCu=0 .84) ,其他供试重金属浓度与蚯蚓死亡率和生长抑制率相关性不显著 .蚯蚓个体对重金属毒性的耐受程度差别较大 .其毒性阈值 (引起个体蚯蚓死亡浓度 )分别为 :Cu 30 0mg·kg-1,Zn 130 0mg·kg-1,Pb 170 0mg·kg-1,Cd 30 0mg·kg-1.LC50 分别为 :Cu 40 0～ 45 0mg·kg-1,Zn15 0 0～ 190 0mg·kg-1,Pb2 35 0～ 2 40 0mg·kg-1,Cd 90 0mg·kg-1.在Cu、Zn、Pb、Cd单一污染引起 >10 %蚯蚓死亡的浓度下 ,复合污染导致 10 0 %蚯蚓死亡 ,表明复合污染极强的协同效应 .