镉胁迫对甜高粱种子萌发及幼苗生长的影响

为探讨镉对甜高粱种子萌发的影响,以辽甜1号为研究对象,研究不同浓度镉胁迫下的甜高粱种子萌发和幼苗生长特性。结果表明,甜高粱种子的发芽势、发芽率、发芽指数、活力指数均随镉胁迫浓度增加表现出先增加后减少的趋势,都在T2处理时表现为最大;镉会抑制甜高粱幼苗的根和芽生长,镉胁迫浓度增加,抑制作用显著增强,且对根长的抑制作用明显大于芽长;甜高粱种子根、芽的耐性指数均随镉胁迫浓度增加而显著降低,且根耐性指数均低于芽耐性指数。     

Cu2+对黄瓜发芽期发育和生理特性的影响

研究了Cu2+浓度对黄瓜发芽期发育和生理特性的影响。结果显示,低浓度Cu2+(25 mg/L)处理对黄瓜种子萌发和幼苗生长有促进作用,其种子发芽率、发芽势、发芽指数、活力指数、根长、下胚轴长、下胚轴粗度、生物量和相对含水量均高于对照及其他浓度处理;而幼苗的质膜相对透性、丙二醛含量、可溶性糖含量、脯氨酸含量及保护酶活性均在此浓度得达最低。但在高浓度Cu2+(Cu2+浓度在50~300mg/L时)处理下,随着Cu2+浓度增加,黄瓜种子萌发的各项指标开始下降,幼苗生长的各项生理指标开始上升,对黄瓜种子发芽和幼苗生长产生抑制作用,并在300mg/L时抑制作用最显著。     

铜对小白菜的毒性效应及其生态健康指标

以小白菜地上部分及根系重量、叶绿素值(SPAD值)以及与抗逆性有关的丙二醛(MDA)、超氧化物歧化酶活性(SOD)、脯氨酸含量等作为毒性指标,研究了04～00.mg/kg外源铜对青紫泥小白菜生长的影响,并应用“生态剂量”概念计算青紫泥栽培小白菜的铜污染安全指标及食品卫生指标。结果表明,低浓度铜(200.mg/kg)则造成小白菜减产,400.mg/kg的外源铜使小白菜减产84%;铜污染使根系重量下降表现出与地上部分同样的趋势。SPAD值随铜污染浓度的增加而呈线性下降;铜污染浓度低于100.mg/kg有促进根体积、根长度、根表面积增加的趋势,但超过200.mg/kg的铜浓度则显著降低根长、根体积和根表面积。在与重金属污染引起的抗逆性有关的生理生化指标中,脯氨酸最为敏感,铜浓度小于50.mg/kg或大于200.mg/kg都能显著影响脯氨酸含量及SOD活性;与脯氨酸的变化一样,高浓度铜增加了MDA含量;青紫泥铜污染的临界指标为171.mg/kg。     

施用富Cu猪粪后潮土-小麦系统Cu的传递与积累

以华北地区典型土壤潮土为供试土壤,将猪粪(施用量占风干土重的0%,1%和3%)和不同Cu浓度(0,100,200,400,600和800 mg kg-1土)的CuSO4溶液腐化后与土壤混合均匀进行盆栽试验,以研究施用富Cu猪粪对土壤和小麦各器官(根、茎叶和籽实)Cu积累及对潮土—小麦系统Cu迁移转化的影响。结果表明,土壤全Cu、有效态Cu和小麦植株各器官Cu浓度均随着外源Cu浓度的增加而显著增加,在相同外源Cu浓度条件下,成熟期各指标浓度相对拔节期有所下降。外源Cu只有极少量从土壤向小麦转移,且在小麦各器官Cu浓度顺序为根>>茎叶/籽实。相对于拔节期,小麦成熟期根部Cu积累量显著上升,茎叶Cu积累量无显著变化,但根部和茎叶Cu浓度均显著下降。施用1%猪粪明显降低了Cu的可移动性,而3%猪粪在一定程度上增加了Cu的传递与积累。当外源Cu浓度≥200 mg kg-1时,0%和3%猪粪施用的处理籽实中Cu浓度超过了人体能接受的Cu毒性极限(20 mg kg-1),施用1%猪粪则潜在的降低了Cu在籽实中的积累。     

铜盐毒害对紫鸭跖草养分吸收和生长的影响

通过含有不同浓度CuSO4的Hoagland营养液培养紫鸭跖草枝条,研究了紫鸭跖草对铜的耐性和超积累以及铜胁迫下紫鸭跖草生长和营养状况.结果表明:紫鸭跖草根部铜的积累量低浓度Cu2 供应时增加幅度不大,高浓度Cu2 供应时增加幅度较大;茎部的情况与根部相似;但叶部在低浓度Cu2 供应时铜的积累量几乎没有变化,高浓度Cu2 供应时铜的积累量增幅较大.在500 μmol · L-1和1 000 μmol · L-1铜处理下,紫鸭跖草整株铜积累量分别为866 mg · kg-1(DW)和1 130 mg · kg-1(DW).紫鸭跖草对铜的吸收和转运效率与铜的供给量呈正相关性.100～250 μmol · L-1铜的供应能明显促进紫鸭跖草生长.高浓度铜促进了钾、钙的吸收而阻碍了锌的吸收及镁向地上部分的运输,尽管如此,氮、磷、钾、镁、钙的浓度均在满足常规植物正常生长的浓度范围内.铜胁迫下对根部蛋白质表达活跃,氨基酸含量增加.研究结果表明紫鸭跖草对铜有很大耐性和富集能力.     

三种抗生素与铜复合污染对土壤过氧化氢酶活性的影响

为分析抗生素与重金属单一及复合污染对土壤过氧化氢酶活性的影响,以三种兽用抗生素恩诺沙星(Enrofloxacin,ENR)、土霉素(Oxytetracycline,OTC)、磺胺二甲嘧啶(Sulfamethazine,SM2)和重金属铜(Cu)为目标污染物,采用高锰酸钾滴定法,研究其对土壤中过氧化氢酶活性的影响。结果表明,单一污染下,中低浓度的ENR各处理对酶活性有一定激活作用,最大激活率为5.52%;OTC处理组随着污染物浓度的增加,对酶活性的抑制作用增大,抑制率最大为8.36%;SM2处理初期,中低浓度处理组对酶有激活作用,最大激活率为7.46%,处理21 d,高浓度处理组对酶活性有显著促进作用,激活率为1.71%。Cu在第28 d时对过氧化氢酶活性表现为抑制。复合污染下,ENR与Cu复合污染组对过氧化氢酶活性的影响随污染浓度增加先抑制后激活;OTC与Cu处理第7 d,各浓度组与对照差异均不显著,14 d后,高浓度组产生抑制作用,抑制率最高为3.58%;SM2与Cu高浓度处理组在第7 d对土壤过氧化氢酶活性表现为明显激活作用,激活率高达10.00%,14 d后转为抑制作用,28 d时抑制率最高为4.49%。研究表明,单一污染下,抗生素对土壤过氧化氢酶的影响与其类型、暴露浓度以及暴露时间有关。复合污染下,抗生素和Cu的交互作用存在差异,表现为拮抗和协同两种作用,不仅与抗生素种类、复合污染浓度比例、暴露时间有关,还与抗生素和Cu配位反应产生复合物的比例有关。     

蚓粪对黑麦草吸收污染土壤重金属铜的影响

在长江冲积物形成的高沙土中加入CuSO4.5H2O模拟土壤污染,使Cu污染浓度分别为200、400、600 mg kg-1,并设置加蚓粪(15%)和加原土(15%)处理,二处理各设种植黑麦草(Lolium multiflorum)和不种黑麦草培养试验,研究蚓粪对黑麦草生长及对Cu吸收的影响,以揭示蚓粪在Cu污染土壤植物修复中的作用。结果表明:蚓粪显著增加了黑麦草的地上部和地下部的生物量(p<0.001**)以及根系的长度、表面积、体积和根尖数(p<0.05*),在Cu浓度为200 mg kg-1时促进作用最大;蚓粪还显著提高了黑麦草地上部Cu的浓度及累积量,但显著降低了地下部的Cu浓度(p<0.05*),而对地下部的铜累积量没有影响,显示蚓粪能促进Cu从根系向地上部的运移及在地上部的富集。通过对土壤的pH和Cu的形态特征分析,发现种植黑麦草处理降低了土壤的pH并增加了可交换态铜的含量,而且这种作用在加入蚓粪后更加明显。推测蚓粪主要通过促进黑麦草根系的生长和活性而影响根系周围环境,提高重金属铜的生物有效性进而增加植物对铜的吸收。     

线虫群落结构对外源添加不同浓度铜污染物的响应

通过盆栽模拟试验的方法研究外源添加铜对土壤线虫群落结构的影响,试验添加Cu浓度分别为50 mg kg-1,100 mg kg-1,200 mg kg-1,400 mg kg-1干土和不施加污染物的对照处理,在小麦的生长关键期取样。试验结果表明:线虫不同营养类群对铜污染物的响应在小麦拔节期比较明显,拔节期捕食/杂食线虫的数量在外源添加400 mg kg-1Cu处理中显著低于对照,而不同浓度铜对食细菌线虫和食真菌线虫的影响则表现为低浓度促进高浓度抑制。线虫的生态指数对不同浓度铜污染物反映比较敏感,在小麦苗期和拔节期,与对照相比,不同浓度铜处理中线虫多样性降低,而优势度增加;自由生活线虫成熟度指数对不同浓度铜反映相对滞后,只在小麦成熟期表现出差异,即高浓度铜处理中线虫成熟度指数显著低于对照。     

向日葵对土壤中铜的积累作用研究

温室内不同Cu浓度添加土壤的向日葵盆栽试验表明,向日葵植株的部分生物学性状如地上部干物质量、地下部干物质量、最大单叶面积随土壤中Cu浓度的增加而降低,土壤中添加20mg/kgCu对向日葵根部生长抑制作用最大,而植物高度在添加100mg/kgCu浓度时最高。且不同Cu浓度处理下向日葵对Cu的积累能力不同,但植物各部分Cu含量均随土壤中添加Cu浓度的增加而增加,但在100mg/kgCu浓度处理下,向日葵对Cu的积累主要集中在根部,地上部分Cu含量很低,在200mg/kgCu浓度处理下,向日葵叶中Cu含量超过根部,达857±297mg/kg干重,Cu积累的叶根比达1.27,说明当土壤Cu浓度较高时,Cu在向日葵地上部有较高的Cu积累,集中收获植株地上部分,可移出土壤中的过多有效铜,但生长受到抑制。使用向日葵修复高浓度Cu污染土壤时,还需考虑采用其他手段接种根际微生物、转基因、设施农业环境工程技术等来增加其生物产量。     

铜耐性优势植物根际土壤铜抗性菌株的筛选及其对铜的促溶作用

从铜矿废弃地重金属耐性优势植物根际土壤中分离筛选到两株抗高浓度Cu的细菌菌株HQN2和JYC17.对菌株HQN2和JYC17溶解难溶性Cu的作用进行了研究.结果表明:菌株HQN2和JYC17具有明显的溶解碳酸铜的能力,与接灭活菌对照相比,菌株HQN2和JYC17分别使培养液中水溶性Cu含量增加306%和136%,培养液的pH由初始的7.00分别降低到4.08和4.46.另外,Cu能促进供试菌株有机酸(葡萄糖酸、苹果酸和乙酸等)的合成.菌株HQN2和JYC17对土壤中难溶性Cu亦有明显的促溶作用.与接灭活菌对照相比,菌株JYC17和HQN2分别使土壤中交换态Cu含量增加110%和270%.经生理生化特征分析及16S rDNA序列分析,菌株HQN2和JYC17分别被鉴定为节杆菌属(Arthrobacter sp.)和微杆菌属(Microbacterium sp.).     

污泥-铜尾矿体系下pH、盐分和重金属对大麦根伸长的生态毒性效应

以无锡芦村污水处理厂的污泥为例,室内分析了污泥对铜陵、德兴铜尾矿的酸碱缓冲能力和田间持水能力的改善,并通过生态毒理试验初步评估了施用该种污泥复垦铜尾矿的可行性。试验表明,在污泥施用量为0、10、30、50、100、130、170、200g/kg时,铜陵尾矿上大麦根伸长随着污泥施用量的增加而受抑制,根长和盐分呈显著负相关关系。污泥与德兴酸性尾矿混合时,大麦根伸长呈先增后减的趋势,在污泥加入量为0~100g/kg时,根长随pH的升高和有效Cu的减少而增长,而在污泥加入量为100~200g/kg时,根长随盐分增加而受抑制;CaCl2提取的Cu随有机质增加而明显减少,CaCl2提取的Zn对pH变化比较敏感。     

Effect of aluminum on growth and chemical composition of marigolds

Marigold (Tagetes erecta L. cv. ‘Discovery Yellow’, “Perfection Yellow’, ‘Inca Yellow’, and ‘Merrymum Yellow') were grown in aluminum (Al) solution culture concentrations of 0, 1, or 4 mg/L. Aluminum increased root length and weight, but had no effect on stem and leaf weight. Uptake and stem and leaf tissue nutrient concentration of phosphorus (P), calcium (Ca), and magnesium (Mg) were reduced by the Al treatments. The Al treatments increased stem and leaf concentrations of potassium (K) and decreased the concentrations of manganese (Mn), iron (Fe), copper (Cu), and zinc (Zn). No typical Al‐toxicity symptoms were observed in the roots. Root stunting caused by Fe toxicity was alleviated by the Al treatments.     

Response of Rice Seedlings to Copper Toxicity and Acidity

Metal toxicity and soil acidity affect plant growth. A hydroponic experiment was conducted to simulate effects of pH and copper concentration [Cu] on early growth and biomass production of high-yielding rice seedlings (Oryza sativa L. cv. ‘NIAB 6’). The rice seedlings were allowed to grow in Yoshida nutrient solution with 1 (control), 8, 16, and 32 μM Cu at buffered pH levels of 4.5, 5.0, and 5.5, respectively. Shoot and root growth, leaf chlorophyll content, and root lipid peroxidation and K⁺ leakage of 15-day-old rice seedlings were determined. Results show that [Cu] had significant adverse effects on rice seedlings. Shoot height and root length were reduced by 18%–60% and 7%–69%, respectively, compared with the control, and shoot and root weight decreased by 26%–56%, and 25%, respectively, in response to progressive increases in [Cu]. Similarly, leaf chlorophyll content decreased by 150%–245% compared with the control treatment. Rice seedling roots suffered from significant increases in lipid peroxidation followed by K⁺ leakage (> 8–23 times) in response to increasing [Cu]. Averaged across [Cu], seedling growth and biomass were greater at pH 5.5 than at other pH treatments. In some instances, increasing pH minimized the adverse effects of Cu at low concentrations on rice seedlings.     

姜花在Cu胁迫下的耐性机理研究

采用模拟湿地盆栽试验,研究了姜花在Cu胁迫下的积累、分布、化学形态和富集能力。结果表明：（1）姜花对Cu的积累能力随Cu处理浓度的增加而增大,但各部位对Cu的积累具有明显的差异性。当Cu处理浓度≤150mg·kg。时,其积累能力表现为根〉叶〉茎;当Cu处理浓度≥200mg·kg。时,其积累能力表现为叶〉根〉茎。（2）Cu在姜花叶片细胞中的分布具有选择性,其主要分布位点为细胞可溶性部分和细胞壁部分,而在细胞器中Cu的含量较低。（3）Cu在姜花根、茎和叶中赋存的化学形态有明显差异。在根部,Cu的化学形态主要以乙醇提取态和水提取态为主;在茎部,Cu均以氯化钠提取态为主;而叶部Cu主要以活性较低的氯化钠提取态、醋酸提取态和盐酸提取态存在。（4）姜花对Cu具有一定的富集能力,但富集能力不强,当Cu浓度达到400mg·kg^-1以上时,姜花植株便出现了较明显的毒害症状并随之死亡,因而姜花尚未达到超富集植物的标准。可见,姜花在Cu胁迫下具有一定的耐受性,分布选择性和富集能力,将其运用于湿地Cu污染修复中,将极大地缓解重金属Cu污染给环境带来的压力。     

Effects of Salinity and Copper on Growth and Chemical Composition of Pistachio Seedlings

The effects of five salinity levels and four copper levels on growth and chemical composition of ‘Ghazvini, pistachio seedlings were studied under greenhouse conditions in a completely randomized design with three replications. Leaf area, stem height, shoot and root dry weights were determined on 24th week after planting. Copper (Cu), phosphorus (P), sodium (Na), and chlorine (Cl) total uptake in shoot and root of plant were measured. The results showed that salinity decreased growth parameters. Low levels of Cu application had no significant effect on leaf area, shoot and root dry weights while decreased stem height. The highest level of Cu (7.5 mg Cu kg^?1 soil) significantly increased leaf area and shoot dry weight but decreased stem height. Salinity decreased Cu and P uptake in the shoot and root, but increased total sodium and chloride uptake. Cu application increased shoot total P uptake and decreased root total Na uptake.     

Revegetation of copper mine tailings with ryegrass and willow

To restore vegetation on metal mine tailings is very difficult because they often contain high concentrations of heavy metals, low nutrient content and low water retention capacity. This study involved 3 experiments that evaluated the effects of 4 treatment amendments: montmorillonite, rice straw, organic manure and chemical fertilizer on the growth of ryegrass (Loliurn perenne L.) and willow (Salix virninalis L.) with Cu and Zn mine tailings from two mining areas. The results showed that ryegrass was the most tolerant of 4 crops to Cu toxicity. Also when organic manure, which contained high concentrations of inorganic salts, was added to the mine tailings, it significantly hindered ryegrass growth (P=0.05).Meanwhile, with ryegrass organic manure significantly increased (P=0.05) the extractable Cu concentration in both mine tallings. When montmorillonite was used as a mine tailings amendment with willow, the height and tress number at the 1st cut were significantly greater (P = 0.05) than a control without montmorillonite. However there was no significant difference for height, tress number, dry weight or root dry weight at the 2nd cut. So, amendment applications to reduce metal toxicity and increase nutrients retention in mine tailings were essential during revegetation of mine tailings.     

Copper Uptake and Tolerance in Two Contrasting Ecotypes of Elsholtzia argyi

Abstract

Information is desired on plant species that have a great potential in phytoremediation of copper (Cu) contaminated soils. Two contrasting ecotypes of Elsholtzia argyi were comparatively studied using nutrient solution culture for their growth response and uptake, distribution, and translocation of Cu. The results show that the ecotype from an old mined area (Sanmen-ecotype) had greater tolerance to Cu than that from the nonmined area (Jiuxi-ecotype) based on dry matter yield at different Cu supply levels. Inhibited root and leaf growth was noted at the external Cu levels > 50 µmol L^?1 for the Sanmen-ecotype, and at the Cu supply levels > 5 µmol L^?1 for the Jiuxi-ecotype. Stem growth was most sensitive to Cu toxicity in E. argyi, and was inhibited at the Cu levels ≥ 2.5 µmol L^?1 for Jiuxi-ecotype and ≥ 25 µmol L^?1 for Sanmen-ecotype. Root Cu concentrations were higher in Sanmen-ecotype than in Jiuxi-ecotype, but leaf, especially stem Cu concentrations were much lower in the former than in the latter. Furthermore, Jiuxi-ecotype was much more efficient than Sanmen-ecotype in the translocation of Cu from root to the shoot, and it had higher ratios of stem/root and leaf/root Cu concentration. At the Cu supply levels higher than 10 µmol L^?1, root concentrations of potassium (K), calcium (Ca), magnesium (Mg), manganese (Mn), and zinc (Zn) considerably decreased in Jiuxi-ecotype, but were not affected or even increased in Sanmen-ecotype. Zinc concentrations in the stems, particularly in the leaves of Sanmen-ecotype increased by 3 folds, but were hardly changed in Juixi-ecotype when grown at the Cu levels higher than 10 µmol L^?1. These results indicate that the Sanmen-ecotype of E. argyi is a Cu-tolerant ecotype, and its tolerance to high Cu levels was mainly related to its extraordinary capability to restrict Cu uptake, especially Cu translocation from root to the shoot, probably by competitive uptake and translocation of Zn.     

Interactive Effect of Soil Salinity and Copper Application on Growth and Chemical Composition of Pistachio Seedlings (cv. Badami)

The effects of five salinity levels and four Cu levels on growth and chemical composition of Badami pistachio seedlings were studied under greenhouse conditions in a completely randomized design with three replications. Growth parameters were determined on the 24th week after planting. Total elemental uptake amounts in shoot and root of plant were measured. Results showed that salinity decreased leaf area, stem height, and shoot and root dry weights. Application of 2.5 and 5 mg copper (Cu) kg^?1 soil significantly increased root dry weight, whereas it had no significant effects on shoot dry weight and leaf area. Application of 7.5 mg Cu kg^?1 soil had a negative effect on stem height. Salinity declined shoot and root total Cu and phosphorus (P) uptake amounts but increased shoot and root total sodium (Na) and chlorine (Cl) uptake amounts. Copper increased shoot and root total Cu uptake amounts, root total P uptake, and shoot total Na uptake but decreased shoot total Cl uptake.     

铅胁迫对19个品种草坪草种子萌发和幼苗生长的影响

用浓度分别为0(对照)、200、400、600mg/L的Pb2+分别处理19个品种草坪草的种子,测定了供试种子发芽势、发芽率、幼苗根长、苗长、鲜重、叶绿素含量、丙二醛含量等7项指标,比较19个品种草坪草生长初期耐铅性的强弱。结果表明：在不同浓度Pb2+胁迫下,有的品种种子发芽势、发芽率、幼苗根长、苗长、鲜重、叶绿素含量呈先上升后下降的变化趋势,有的品种这些指标呈下降变化趋势;有的品种丙二醛含量呈先下降后上升的变化趋势,有的品种丙二醛含量呈上升的变化趋势。通过聚类分析,Pb2+400 mg/L胁迫下将19个草坪草品种的耐铅性分为3 类;耐铅性强的品种有热浪;耐铅性较强的有星火、回报、绿城、爱瑞3号、家园、美洲豹3号、3A、麦哲伦、自豪、里园2号等; 耐铅性弱的有晚霞、本特、橄榄球2号、高地、优异、优美、午夜、抢手股;并通过主成分分析进一步确定19个品种在Pb2+400 mg/L胁迫下耐铅性由强到弱的顺序为热浪＞星火＞爱瑞3号＞3A＞回报＞美洲豹3号＞绿城＞家园＞自豪＞里园2号＞麦哲伦＞晚霞＞本特＞橄榄球2号＞高地＞优美＞抢手股＞午夜＞优异。     

不同生长环境下黄顶菊浸提液对多年生黑麦草萌发与生长的影响

为阐明黄顶菊入侵机制,本文在调查不同生境下黄顶菊居群特征的基础上,进一步采用植株浸提液生物测试的方法研究了不同生境、生长密度及替代植被下黄顶菊对多年生黑麦草的化感潜力。结果表明:黄顶菊的化感作用强弱与其入侵能力存在一定相关性,黄顶菊浸提液的化感潜力随浓度升高而增强;不同植株组织浸提液的化感潜力存在显著差异,表现为地下部分明显低于地上部分;不同生境下黄顶菊浸提液的化感潜力顺序为水边>果园>路边,50 g.L 1茎叶浸提液对多年生黑麦草发芽率化感效应敏感指数分别为2.83(水边)、1.31(果园)和0.71(路边);不同密度黄顶菊的茎叶化感潜力顺序为高、中密度区显著大于低密度区,50g.L 1浓度浸提液对多年生黑麦草发芽率化感效应敏感指数分别为3.91(高密度)、4.89(中密度)和0.29(低密度);根部浸提液的化感潜力顺序则相反。不同替代植被下茎叶浸提液的化感效应为混种>单种,而根系浸提液的化感效应敏感指数则差别不大。因此,黄顶菊不同组织器官化感活性物质分配不同,同时其化感效力能够适应环境条件而发生变化,这可能是造成黄顶菊在不同环境中入侵效果差异的原因之一。