A pot experiment was conducted to study the effects of the combined cadmium and lead stress on physiological characters of kentucky bluegrass seedlings. The results showed that the Cd2+ stress had significant (P

本试验采用盆栽的方法，研究了土壤镉铅复合胁迫对草地早熟禾(Poa pratensis)幼苗生理特性的影响。结果表明，不同Cd2+胁迫显著(P

In order to clarify the physiological effect of nitrogen on plant exposed to metals, Eucalyptus grandis was used as exprimental material to study the responses of growth and photosynthesis to the heavy metals (Cd 2+ 、Pb 2+ and Cu 2+ ) and nitrogen addition. Results showed that (1) chlorophyll content, photosynthesis rate, and quantum yields of PSⅡ of the plants exposed to heavy metals all significantly decreased when compared to the controls; (2) nitrogen addition could increase content of chlorophyll a (Chl a) and chlorophyll b (Chl b), photosynthesis rate, and PSⅡquantum yields of plants under stress of heavy metals. The above results indicated that nitrogen played an important role in detoxification of heavy metals, and could alleviate the toxic effect of heavy metals, which could increase content of chlorophyll and photosynthesis in plants.

为验证氮在植物解除重金属毒害中的积极作用和生理机制,本试验对巨桉( Eucalyptus grandis )幼苗在3种重金属(Cd、Cu和Pb)处理下增施氮肥的生长和光合生理效应进行研究。结果表明:Cd 2+ 、Cu 2+ 和Pb 2+ 处理下,巨桉植株的叶绿素含量、光合作用、PSⅡ原初光化学反应量子产率等均显著低于对照植株;而在重金属处理的同时增施氮肥,则能显著促进植株生长,提高叶绿素含量,增强光合作用和PSⅡ原初光化学反应量子产率。由此说明,氮在植物对重金属的解毒中起到重要作用,增施氮肥可缓解重金属对植物的毒害,提高叶绿素含量和光合速率。

The physiological and biochemical response of creeping bentgrass to cadmium stress were studied in the present study. The results showed that cadmium stress exhibited inhibitory effects on creeping bentgrass initial growth and the inhibition effects increased with the cadmium ion concentration increased. When cadmium ion concentration was 50 mg·L-1, seed germination rate, shoot length, root length and seedling fresh weight were 47%, 87%, 54% and 83% of that of control, respectively. Seed germination was completely inhibited by 400 mg·L-1 cadmium. Cadmium ion had significant effects on contents of chlorophyll, malonaldehyde(MDA) and activities of superoxide dismutase(SOD), peroxidase(POD). With cadmium ion concentration increased, chlorophyll content decreased whereas MDA content increased gradually. When cadmium ion was 200 mg·L-1, chlorophyll content and MDA content were 37% and 864% of that of control, respectively. SOD activity reached maximum of 1 314 U·h-1·g-1 with lower cadmium ion concentration of 50 mg·L-1. SOD activity decreased with higher cadmium ion concentration although it was still higher than the control. POD activity had similar variations with SOD activity and reached maximum of 225 U·s-1·g-1 with lower cadmium ion concentration of 100 mg·L-1. The response of the 90 day old plants germinated from seeds treated with cadmium (2~100 mg·L-1) was similar with seedlings. With cadmium ion concentration increased or cadmium stress period extended, chlorophyll content decreased whereas MDA content increased gradually and both SOD and POD activities increased first and then decreased.

本研究分析了镉胁迫对匍匐剪股颖种子萌发、幼苗和植株生长及生理生化的影响。结果表明，1)不同浓度的Cd2+（50~400 mg·L-1）对匍匐剪股颖（Agrostis stolonifera）初期生长具有抑制作用，这种抑制作用随着Cd2+浓度的增加而增强。当Cd2+浓度为50 mg·L-1时，发芽率、芽长、根长和苗鲜重分别只有对照（0）的47%、87%、54%和83%。当Cd2+浓度为400 mg·L-1时，则完全抑制了种子的萌发；2)不同浓度的Cd2+（50~200 mg·L-1）对幼苗叶绿素含量、丙二醛（MDA）含量、超氧化物歧化酶(SOD)活性和过氧化物酶(POD)活性具有显著影响。随着Cd2+浓度的升高，叶绿素含量逐渐下降，丙二醛含量不断上升，在200 mg·L-1的Cd2+胁迫下，叶绿素和丙二醛含量分别是对照的37%和864%；在Cd2+浓度较低时(50 mg·L-1)，SOD活性高于对照，达到1 314 U·h-1·g-1，更高的浓度引起活性降低，但始终高于对照；POD的活性变化与SOD相似，在Cd2+浓度为100 mg·L-1时最大值达到225 U·s-1·g-1；3) Cd处理（2~100 mg·L-1）播种后90 d的植株，4个指标的变化趋势和Cd处理幼苗的变化基本一致。随着Cd2+浓度的升高及胁迫时间的延长，叶绿素和丙二醛含量分别不断下降和上升；SOD和POD活性均是先上升后下降。

Viola, Botanic resources, Exploitation and utilization

介绍了中国堇菜属野生植物的资源数量、分布及观赏特性, 并分析了堇菜属植物的园林开发前景。关键词：堇菜属; 植物资源; 开发利用

It is the main way of city landscape greening that landscape greenery space should be mainly composed of native plants. In order to provide theoretical reference for native herbaceous ground cover plant application in Beijing urban area, this study was carried out in Beijing Olympic Forest Park, which is wellknown for native plants application. By using quadrat method, plant species, frequency and growth vigor of native herbaceous ground cover plants were investigated in the park. Results show that there are 44 species of native herbaceous ground cover plants in the whole park (including the north park and the south park), which belong to 43 genera and 22 families. Besides, native herbaceous ground cover plant species in the north park is more than that in the south park. Frequency of plants belonging to Asteraceae, Leguminosae and Cruciferae is higher than that of other families. Three species, Ixeris sonchifolia, Melilotus suaveolens and Orychophragmus violaceus, are used most widely in the park. A suggestion is given that Orychophragmus violaceus, Ixeris sonchifolia, Taraxacum officnala, Viola yedoensis, Potentillae chinensis, Medicago sativa, Melilotus suaveolens and Vicia sativa should be widely applied in Beijing landscapes.

以乡土植物为主体的园林绿地建设是城市园林绿化发展的主要方向。本研究通过对北京奥林匹克森林公园乡土草本地被植物种类、频度和生长势的调查发现，公园内有乡土草本地被植物44种，隶属于22科43属。菊科、豆科和十字花科的频度最高，抱茎苦荬菜(Ixeris sonchifolia)、草木樨(Melilotus suaveolens)和二月兰(Orychophragmus violaceus)在全园分布最广泛。建议将二月兰、抱茎苦荬菜、蒲公英(Taraxacum officnala)、紫花地丁(Viola yedoensis)、委陵菜(Potentillae chinensis)、草木樨、紫花苜蓿(Medicago sativa)和野豌豆(Vicia sativa)8种植物在北京城区园林绿化中大量应用。

通过野外调查和温室试验, 发现并证实宝山堇菜( Viola baoshanensis )是一种Cd超富集植物. 自然条件下, 宝山堇菜地上部Cd平均含量为1168 mg/kg, 变化范围为465~2310 mg/kg; 地下部Cd平均含量为981 mg/kg, 变化范围为233~1846 mg/kg. 地上与地下部Cd含量比值变化范围0.41~2.22, 平均为1.32. Cd生物富集系数变化范围为0.7~5.2, 平均为2.38. 营养液培养试验研究表明, 宝山堇菜地上部Cd含量随生长介质中Cd浓度的增加而呈线性增加. 营养液Cd浓度为50 mg/L时, 地上部Cd平均含量达到4825 mg/kg, 在Cd浓度为30 mg/L时, 生物量达到最大值; 地上与地下部Cd含量的比值变化范围为1.14~2.22, 平均为1.67, 显示宝山堇菜不仅可以超量吸收Cd, 而且可以从地下向地上部有效输送. 宝山堇菜的发现将为Cd超富集植物的生理、生化、遗传和进化及其在Cd污染土壤修复方面的研究提供新的重要材料.

Effect of combined heavy metal stress of copper, zinc, lead and cadmium on the antioxidant enzymes activities by 5 kinds of trees,such as Schima superba Gardn , Cinnamomum camphora Presl , Acer palmatum Thunb, Castanopsis sclerophylla Schott and Neolitsea sericea Kiodz were investigated in the pot experiments. The results indicated that high concentrations of combined pollution significantly inhibited plant growth, and the damage of plants became light with the decrease of the concentration. With the increase of the concentration of heavy metal compound, chlorophyll content of the 5 kinds of plants with different treatments reduced, highly concentrated treatments and the CK reached the remarkable level (P Schima superba Gardn drops obviously compared with CK, Neolitsea sericea Koidz drops smallest. Soluble protein content of 5 kinds of plants with different treatment compared were not remarkable, but the MAD content with the CK reached the remarkable level (P Neolitsea sericea Koidz dropped most slightly compared to CK, but Schima superba Gardn dropped most remarkably. The results suggested that the stress resistance abilities of 5 plants to the heavy metal compounds was in the order: Neolitsea sericea Koidz > Cinnamomum camphora Presl > Castanopsis sclerophylla Schott > Acer palmatum Thunb > Schima superba Gardn.

研究了不同浓度Cu-Zn-Pb-Cd复合重金属污染对木荷（ Schima superba Gardn .）、香樟（ Cinnamomum camphora Presl .）、青枫（ Acer palmatum Thunb .）、苦槠（ Castanopsis sclerophylla Schott .）和舟山新木姜子（ Neolitsea sericea Koidz .)5个浙江地区常见种植的园林常绿阔叶树种抗氧化酶活性的影响。结果表明，高浓度复合污染能显著抑制植物的生长，受害现象严重，中浓度次之，低浓度大部分植物危害较轻。随着土壤中复合重金属浓度的增加，5种植物不同处理的叶绿素含量都降低，中、高浓度处理与对照相比均达显著水平（P＜0.05）和极显著水平(P＜0.01)；其中在高浓度处理条件下，木荷下降最为显著，舟山新木姜子下降最小。5种植物不同处理的可溶性蛋白质含量与对照相比均不显著，但是丙二醛含量与对照相比均达显著水平（P＜0.05）和极显著水平（P＜0.01）。SOD、POD和CAT的活性均呈现出先升后降的趋势，表明5种植物都具有一定的抗逆能力。在高浓度处理条件下，舟山新木姜子CAT、POD和SOD活性比对照下降最少，木荷下降最为显著。5种常绿阔叶树种对复合重金属胁迫的耐受能力依次为：舟山新木姜子>香樟>苦槠>青枫>木荷。

A pot experiment was conducted to study the cadmium (Cd) tolerance and enrichment characteristics of Eulaliopsis binata . Applying low concentration Cd (5 mg·kg -1 ) could boost the growth and physiological vigor of E. binata , with the twelve indexes such as biomass and net photosynthetic rate, etc. increased by 1.0%-15.5%, compared with CK; while applying high concentration Cd (>5 mg·kg -1 ) had negative effects on the growth of E. binata . Even though the E. binata still finished its physiological circle under the application of 100 mg Cd·kg -1 , the biomass and net photosynthetic rate were decreased by 27.0% and 25.6%, respectively, in comparison with CK. The Cd conten t in the organs of E. binata increased greatly with increasing concentration of applied Cd. The Cd content in roots was from 350 mg·kg -1 to 500 mg·kg -1 , and that in stems and leaves was from 15 mg·kg -1 to 35 mg·kg -1 . When the concentration of applied Cd was -1 , the Cd uptake by E. binata increased with increasing concentration of applied Cd. The Cd content in stems and leaves amounted 15.7%-38.4% of the total uptake, and the ratio of the Cd content in stems and leaves to that in roots was up to 0.62. All the results indicated that E. binata had stronger capability in tolerating, enriching, and transporting Cd, being a potential Cd hyperaccumulator.

利用盆栽试验，研究了龙须草对Cd的耐受能力和富集特征.结果表明：低浓度Cd处理(5 mg· kg -1 )能促进龙须草的生长，增强其生理活性，生物量、净光合速率等12个指标比对照提高1.0%～15.5%；高浓度Cd处理(>5 mg·kg -1 ) 对龙须草的生长产生抑制作用，但当Cd浓度达到100 mg·kg -1 时，龙须草仍能完成正常的生理周期，生物量、净光合速率仅比对照分别下降27.0%和25n6%.龙须草各器官的Cd含量随Cd污染程度的上升而大幅度增加，根的Cd含量为350～500 mg·kg -1 ，茎叶为15～35 mg·kg -1 .在Cd浓度 -1 时，吸Cd量随添加浓度的增大而增大，茎叶吸Cd量占总吸Cd量的15.7%～38.4%，茎叶与根的吸Cd量比值最高可达0.62.龙须草对Cd污染的耐受性、富集和转运能力均较强，是一种潜在的Cd超富集植物.

Tobacco ( Nicotiana tabacum L.) seedlings were used to evaluate the effects of exogenous Cd 2+ on hormone levels, photosynthetic and fluorescent characteristics. Seedlings with six leaves and same height were hydroponically cultivated in Hoagland's nutrient solution for 15 d. The seedlings were aerated 3 h per day and the nutrient solution was renewed every 5 d. Afterwards, Cd (NO 3 ) 2 was added to the nutrient solution at 0, 5, 25 and 50 mg/L, respectively (calculated as pure Cd 2+ ). After Cd 2+ treatment for 3 d, the Cd 2+ contents in leaves were determined with inductively coupled plasma atomic emission spectrometer. The levels of endogenous phytohormones including indoleacetic acid (IAA), gibberellic acid (GA 3 ), abscisic acid (ABA) and zeatin (Z), were assayed with enzyme-linked immunosorbent assay (ELISA). The activities of indoleacetic acid oxidase (IAAO), photosynthetic performance and chlorophyll fluorescent characteristics were measured. Our results showed that the contents of Cd 2+ in leaves significantly increased with the increase of exogenous Cd 2+ concentration, the activities of IAAO decreased at Cd 2+ 5 mg/L, but increased at higher concentrations of exogenous Cd 2+ . At Cd 2+ 50 mg/L, the activity of IAAO increased by 101.71% comparison with the control. Both of the contents of IAA and GA 3 increased at Cd 2+ 5 mg/L, but decreased with the increase of exogenous Cd 2+ concentration. At 50 mg/L Cd 2+ , the contents of IAA decreased by 34.10%, the contents of GA 3 decreased by 39.69%, while the contents of ABA gradually increased with Cd 2+ concentration increase. At 50 mg/L Cd 2+ , the contents of ABA increased by 61.84% comparison with the control. However, the contents of Z sharply decreased with the increase of Cd 2+ concentration, and the contents of Z decreased by 75.35% at 50 mg/L Cd 2+ . Moreover, the contents of chlorophyll a and b and carotenoid decreased significantly with the increase of exogenous Cd 2+ contents. At 50 mg/L Cd 2+ , chlorophyll a and b and carotenoid declined by 34.80%, 55.80% and 73.77%, respectively, comparison with the control. All photosynthetic parameters such as net photosynthesis rate ( Pn ), stomatal conductance ( Gs ), intercellular CO 2 concentration ( Ci ), transpiration ratio ( Tr ) decreased with the increase of Cd 2+ concentration in the nutrient solution. The fluorescent parameters including PSⅡ potential activity ( Fv/Fo ), maximal efficiency of PSⅡ photochemistry ( Fv/Fm ), efficiency of PSⅡ photochemistry ( Ф PSⅡ), photochemical quenching coefficient ( qP ) decreased with the increase of exogenous Cd 2+ . Besides, variable chlorophyll fluorescence ( Fv ) and maximum chlorophyll fluorescence ( Fm ) decreased sharply. Pn, Gs, Ci and Tr decreased by 47.59%, 66.67%, 28.94% and 60.82% respectively, at 50mg/L Cd 2+ . It suggested that Cd 2+ stress disturbed the balance of phytohormone levels in tobacco leaves, and caused the decrease of photosynthetic capacity of tobacco leaves.

以烟草( Nicotiana tabacum L.)为材料,采用不同浓度镉胁迫(0、5、25、50mg/L)的水培试验,分别用电感耦合等离子体光谱仪、紫外分光光度计、酶联免疫法、光合作用仪、叶绿素荧光分析仪研究了镉胁迫3d对叶内镉含量、生长素氧化酶(IAAO)活性、生长素(IAA)、脱落酸(ABA)、赤霉素(GA 3 )、玉米素(Z)的含量、光合特性及荧光特性的影响。结果显示烟草叶内镉含量随着胁迫浓度增加而显著增加;IAAO活性在镉为5mg/L时下降,然后随着镉浓度增加而显著上升;IAA含量在镉为5mg/L时上升,但随着镉浓度增加而显著下降;ABA含量随着镉浓度上升而增加;GA 3 含量在5mg/L时上升,然后随着镉浓度增加而显著下降;Z含量随着镉浓度增加而显著下降;叶绿素a、叶绿素b和类胡萝卜素含量均随镉胁迫浓度增大而显著减少;光合参数中的净光合速率( Pn )、气孔导度( Gs )、细胞间隙CO 2 浓度( Ci )、蒸腾速率( Tr )及荧光参数中的PSⅡ潜在光化学效率( Fv/Fo )、PSⅡ最大光化学效率( Fv/Fm )、PSⅡ实际光化学效率( Ф PSⅡ)、光化学猝灭系数( qP )均随镉胁迫浓度增大而下降。由此可见,镉胁迫打破了烟草激素的平衡,降低了光合能力。

The effects of manganese (Mn), zinc (Zn) and iron (Fe) on growth parameters of drunken horse grass ( Achnatherum inebrians ) over an 8-week period were determined with controlled-environment experiment. Varions were also determined for anti-oxidative enzymes including catalase (CAT), superoxide dismutase (SOD) and peroxidase (POD), proline and malonialdehyde (MDA). The results showed that the plant height, tiller number and aboveground biomass of A.inebrians decreased with the increasing concentration of Mn, Zn and Fe, which had significant differences ( P P A. inebrians increased with the increasing concentration of Mn. CAT and SOD activities significantly ( P -1 treatments and dropped dramatically under the concentrations of 2.5～7.5 mmol·L -1 treatments. Under the stress of Zn, POD activities had a peak value at 7.0 mmol·L -1 , while SOD activities maintained higher level at 14.0 mmol·L -1 treatment which had significant ( P P -1 which had significant ( P A.inebrians had strong tolerance to three heavy metal stresses, as reflected by morphological parameters and reduced ROS injury.

本研究通过比较不同浓度的Mn、Zn和Fe胁迫下醉马草( Achnatherum inebrians )的形态及生理生化指标，探讨醉马草对Mn、Zn和Fe的耐受性。结果表明，随着Mn、Zn和Fe胁迫浓度的增大，醉马草地上生物量积累、株高和分蘖数均显著降低( P P P -1 浓度范围内呈显著( P -1 浓度范围内呈显著( P -1 时达到最大，SOD活性在Zn处理14.0 mmol·L -1 时达到最大，均与其他处理差异显著( P P P -1 时达到最大，并与其他处理差异显著( P <0.05)。综上所述，重金属胁迫对醉马草幼苗生长有一定的抑制作用，同时对其生理生化指标也产生影响。

Aims Excretion of salt by gland had been studied, but the response of salt glands to heavy metals was rarely explored. A hydroponic cultivation experiment was conducted in glasshouse with excretohalophyte to investigate: 1) if salt gland is able to excrete Cd 2+ ions, 2) extent of Cd 2+ tolerance for secretohalophyte, and 3) possible mechanisms by which the excretohalophyte is able to resist Cd 2+  stress. Methods Branches of Tamarix laxa plants were cut into 15 cm sections and propagated for 3 months. They were then transferred into hydroponic cultivation with a Hoagland’s nutrient solution for 20 days and treated with 0, 10, 50, 200 and 500μmol•L-1 Cd 2+ for 2 weeks to determine the uptake and excretion of Cd 2+.  Important findings There were no significant differences in the relative growth rate or water content of the plants between the treatment with 10μmol•L-1 Cd 2+ and the control. When Cd 2+ levels exceeded 50μmol•L -1 ,the shoots of T. laxa suffered toxicity. Cd 2+ excretion through salt glands was detected in all Cd 2+ -added treatments, but the total amount was lower, although the amount of secreted Cd 2+ from salt gland was increased with increasing of Cd 2+ levels. Salt glands excreted Cd 2+ , but the secretion plays less important role in Cd 2+ toxic resistance for excretohalophyte.

在温室条件下采用营养液培养的方法研究了营养液中Cd 2+ 浓度为0、10、50、200和 500 μmol•L-1时，柽柳(短穗柽柳( Tamarix laxa ))对重金 属镉的吸收和分泌特点。研究结果表明：与对照相比，较低浓度(10μmol•L-1)镉处理对柽柳的生长量、含水率均没有显著变化，两周培养期间 内没有出现镉中毒症状；Cd 2+ 浓度增加至50μmol•L-1时对柽柳产生了较强的毒害作用，柽柳的生长量、植株含水率均明显下降，在加镉处理第 十二天时营 养枝开始发黄，出现镉中毒症状。柽柳不同器官镉积累量由大到小依次为：根系>新生营养 枝>枝条。研究还发现，柽柳盐腺能够 分泌镉，分泌镉的量占营养枝中镉含量的0.5%左右；在较低浓度(0～50μmol•L-1)时柽柳对镉的分泌量随着培养液中Cd 2+ 浓度的增加而增加， 并在50μmol•L-1镉处理时，分泌物中Cd 2+ 浓度达到本试验中的最高点，然后镉的分泌量开始下降。这一结果说明，尽管泌盐盐生植物——柽柳 的盐腺能够分泌重金属镉， 但是其数量在植株累积的镉总量中所占甚少，对短穗柽柳耐镉毒害能力贡献不大。

Vegetation dynamics is a new interdisciplinary science, studying the laws of evolution of watershed vegetation under the action of various kinds of ecological stresses, especially soil erosion. Ecological stress is defined as any kind of disturbance, natu

研究了芦苇幼苗体内 Cd的积累、亚细胞微区分布、存在形态和其诱导蛋白以及植物络合素合成抑制剂 (BSO)对芦苇光合作用和生长的影响。在 Cd污染条件下 ,芦苇幼苗植株和根皮层细胞中可积累大量的Cd,但 Cd在芦苇各器官和根皮层细胞亚细胞结构中的分布显著不均 ;Cd在芦苇幼苗体内的分配为 :根 >叶片 >茎 >地下茎 ,在根皮层细胞中的分布为 :细胞间隙 >细胞壁 >液泡 >细胞质。受 Cd污染的芦苇幼苗体内的 Cd以不同化学形态存在 ,其中 Na Cl提取态的 Cd在根和叶片中占的比例均为最大 ,其次为根内的醋酸提取态 ;在叶片中以水提取态为主 ,其它形态的含量相对较低。层析结果表明 ,根和叶片中各存在一种Cd结合蛋白 ,其中根内的 Cd结合蛋白可能是一种植物络合素聚合体。受 Cd诱导 ,芦苇幼苗根中还新合成了一种小分子蛋白或多肽 ,但另有一种蛋白因 Cd影响而消失。此外 ,BSO实验证明了植物络合素对 Cd的解毒作用。可见 ,芦苇的抗 Cd机理与以下几个方面有关 :根部截留 ,细胞间隙积累 ,细胞壁沉淀 ,液泡区域化 ,形成活性较低的难溶化合物 ,形成 Cd结合蛋白。