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1.
Alhagi camelorum cultures provide a system with a high propensity for plantlet regeneration from root, hypocotyl, stem, and leaf explants. Excluding leaf explants, all explants regenerate to form shoot-buds on a simple basal medium suggesting a differential morphogenic potential of different parts of the same plant. All parts of the plant including leaves, form shoot-buds on cytokinin-containing media which markedly promote shoot-bud differentiation, alone or in combination with indoleacetic acid or naphthaleneacetic acid. Rooting occurs on media containing indoleacetic acid and naphthaleneacetic acid. 2, 4-Dichlorophenoxyacetic acid is inhibitory for differentiation and induces callusing. Callus induced on benzylaminopurine and 2,4-dichlorophenoxyacetic acid differentiates to form shoot-buds on transfer to cytokinin-containing medium. Upon transfer to basal medium shoots produce roots. Plants have been transferred to soil.  相似文献   

2.
The fluoride (F) content of groundwater is high in Kuitun, Xinjiang, China, and the amount of F in soil and plants severely exceeds the limit after irrigation. This study designed a potted plant experiment at different concentrations of irrigation water to investigate the migration and transformation pattern of a water–soil–plant system. Three kinds of green vegetables with high metabolism were selected. Different concentrations of NaF solutions were also prepared to simulate the irrigation of farmland in Kuitun. After the plants were irrigated with different NaF concentrations, the contents of water-soluble state fluorine (Ws-F) and the exchange state fluorine (Ex-F) increased. The F content in plants did not increase as the F concentration in irrigation water increased. The F concentration in different plant organs showed the following trend: root > stem > leaf. Bioconcentration factor (BCF) and transfer factor (TF) of plants initially increased and then decreased, indicating that plants exhibit a self-protection ability at high F concentration.  相似文献   

3.
Contamination of surface soils with lead (Pb) is a global concern due to the release of hazardous materials containing the metal element. In order to explore ways to remediate contaminated soils with less impact on environment and costs, this study aimed at screening ornamental plant species exposed to Pb gradient in spiked soils for Pb phytoextraction. Twenty-one ornamental plant species that currently grow in Pakistan, were selected to assess their potential for Pb accumulation. Pot experiments were conducted to evaluate the accumulative properties of the different plant species in unspiked control (Pb = 0) and spiked soils with different levels of Pb at 500, 1000, 1500 and 2000 mg Pb kg?1 of soil. Biotranslocation factor (TF), Enrichment factor (EF) and Bioconcentration factor (CF) were calculated to assess the phytoremediation potential of tested plant species after seven weeks of exposure. Out of 21 plant species, Pelargonium hortorum and Mesembryanthemum criniflorum performed better and accumulated more than 1000 mg Pb kg?1 of shoot dry biomass when they were grown in 500, 1000 and 1500 mg Pb kg?1 contaminated soils. Both plants had no significant (P < 0.05) variation in the total dry biomass with increasing soil Pb concentration indicating a high tolerance to Pb. Considering the capacity of Pb accumulation, total dry biomass, TF, EF &; CF indices, Pelargonium hortorum and Mesembryanthemum criniflorum could be considered as Pb hyperaccumulators and could have the potential to be used in phytoremediation.  相似文献   

4.
5.
The translocation of the radionuclides of Co, Zn, Se, Rb, Y, Tc, and Re into red and green fruits, flesh, seeds, rind, calyxes, flower, leaves, and stems via the root of the tomato plant at two different growth stages was studied by a multitracer technique. The contents (%/g) of Co, Zn, Se, and Y in the roots were the highest among the organs, but only small amounts of them were translocated into the aerial parts after 5 d cultivation with a multitracer. In contrast, Rb, Tc, and Re showed rapid translocation into the stems and leaves from the root. In the plants cultivated for 95 d with a multitracer, Zn, Se, and Rb distributed in all of the organs, Co in the organs except for flowers, and Y, Tc, and Re in the limited organs. The translocation ratio of the elements for the edible part of the plants cultivated for 95 d decreased in the order of Rb>Zn>Co≈Se>Tc≈Y>Re. The transfer factor of the elements for tomato fruit was determined to be in the range of 10−5–10−2. The characteristic translocation behavior of the elements gives us fundamental information on the assessment of pollutant uptake by the tomato plant.  相似文献   

6.
中华猕猴桃胚乳植株后代的观察   总被引:2,自引:0,他引:2  
对438株定植的中华猕猴桃胚乳培.养的试管苗,经四年的田间观察,并进行连续二年结果分析。与对照的母株相比,胚乳植株在株形、叶片大小、果实形态及果实的主要营养成分含量上都有较大的变化。同时还发现,由同一块愈伤组织诱导的胚乳试管苗后代中也有雌、雄性别的分化。胚乳植株后代的多样性,可为中华猕猴桃的选种及品种繁育提供丰富的材料。  相似文献   

7.
喀斯特地区植物钙含量特征与高钙适应方式分析   总被引:14,自引:2,他引:12       下载免费PDF全文
喀斯特地区土壤的高钙含量是影响该地区植物生理特征的最重要环境因素之一。高钙影响植物的光合作用、生长速率及磷代谢, 从而限制了许多物种在该地区的分布。选取贵州4个石漠化程度不同的地区, 测定采集地内45种优势种或常见种的地上部分和地下部分的全钙含量以及土壤的交换性钙含量。通过分析喀斯特地区植物与土壤钙含量的特征发现: 喀斯特地区植物具有较高的钙含量平均值; 土壤交换性钙含量对植物地上部分钙含量的影响总体上不显著, 对植物地下部分钙含量的影响显著; 不同类别植物的钙含量存在显著差异, 蕨类植物地上部分钙含量平均值明显低于被子植物; 不同类别植物钙的分布部位也存在显著差异, 在蕨类植物和单子叶植物中地上部分和地下部分的钙含量相近, 而双子叶植物的地上部分钙含量明显高于地下部分。分析了喀斯特地区14种优势灌木和草本植物地上部分与地下部分钙含量的差异性以及与土壤交换性钙含量的相关关系, 以此为根据将14种优势植物对土壤高钙的适应方式分为3种类型: 随遇型、高钙型和低钙型。随遇型植物的钙含量主要受土壤交换性钙含量影响, 其地上部分和地下部分的钙含量均与土壤交换性钙含量成显著正相关关系; 高钙型植物具有较强的钙富集能力, 其地上部分即使在低钙含量的土壤中也可维持较高的钙含量; 低钙型植物的地上部分即使在高钙含量的土壤中亦可维持较低的钙含量。对植物适应钙的不同方式的研究可用于筛选退化生态系统恢复所需的植物资源。  相似文献   

8.
芥子油苷在甘蓝蚜寄主部位选择行为中的作用   总被引:15,自引:4,他引:11  
阎凤鸣 《昆虫学报》2000,43(3):297-304
利用刺吸电位技术(EPG)记录甘蓝蚜Brevicoryne brassicae在芥菜Sinapis alba 不同部位上的取食行为,同时用高压液相色谱(HPLC)分析芥菜相应部位的芥子油苷(glucosinolates)含量,据此分析芥子油苷在甘蓝蚜对寄主部位偏好行为中的作用。选择芥菜三个部位进行取食行为记录和化学分析,即新出完全叶(第7片)的叶片、叶柄,以及花茎。相对于其它两个部位,甘蓝蚜的口针在花茎上用较少的刺探次数和较短的时间到达韧皮部;一旦口针进入韧皮部持续吸食阶段,蚜虫在三个部位的取食行为没有太大的差异。只在花茎的表皮和皮层中测定到较高含量的白芥子苷(glucosinalbin)。因此,本实验的结果证明,白芥子苷是甘蓝蚜寄主部位选择的关键信号化学物质或取食促进剂。  相似文献   

9.
Hazard evaluation of different heavy metal exposure on the crops cultivated around two abandoned metal mine sites was conducted. Bioconcentration Factor (BCF) of nine heavy metals including Cu, Cd, Hg, As, Cr, Zn, Pb, Mn, and Al in the samples of brown rice cultivated at exposed soil were measured. Soil-plant BCF was measured and compared with Korean and US EPA standards. BCF values of analyzed heavy metals except Hg and As were below the limits. BCF of Hg was over 5 times higher than the standard limit. Excess cancer risk (ECR) and hazard quotient (HQ) values of As was higher than the limit and suggested to have carcinogenic as well as non-carcinogenic threat to the public exposed to the sites. The data presented could be utilized in prioritizing abandoned metal mine sites for health effect survey.  相似文献   

10.
连云港云台山规划造林区植物多样性及其与环境的关系   总被引:1,自引:0,他引:1  
本文运用物种重要值、Shannon-wiener指数、Simpson指数、丰富度指数、Pielou均匀度指数以及Sorensen相似性系数,对连云港云台山规划造林区植物多样性进行研究,并对各个指数与环境因子作相关性分析。结果表明:该区域灌木层以毛壳竹最占优势,草本层中灰绿苔草重要值最高。植物多样性的各个指数基本上都是草本层>灌木层,Sorensen相似性系数表明样地相邻越近植物共有种数就越多。灌木多样性与土层厚度和坡向有关,而海拔和坡向对草本多样性有一定的影响。  相似文献   

11.
Crop contamination with cadmium is a function of soil contamination. Here we study the applicability of the soil solution bioavailability hypothesis to Cd: that is, whether uptake of Cd was more directly related to its concentration or activity in the soil solution than in the soil solid phase. Experimental data from past soil-crop surveys for Cd were used to test this hypothesis. It was also investigated whether pH-dependent desorption of cadmium would be an important mechanisms in affecting cadmium activity and thus uptake. To do so we calculated the correlation between the Cd transfer factor (ratio between Cd level in plant dry material and Cd level in the topsoil) and either the soil pH, or the calculated soil solution Cd concentrations. There was no correlation between the Cd contents of the soil and of the edible parts of leafy plants (endive, spinach and lettuce). There was a strong negative correlation between soil pH and the log transfer factor for Cd at pH 4.5–7.2 and thus plant content. There also was a negative correlation between soil pH and calculated cadmium concentrations in the soil solution. For spinach grown on soils with pH > 7.2 the transfer factor increased, which is tentatively ascribed to cadmium mobilization by dissolved organic matter. The soil solution hypothesis should be further tested by pot and field trials. Special attention should be paid to the role of pH and dissolved organic matter. A C Borstlap Section editor  相似文献   

12.
Strontium (Sr) and calcium (Ca) concentrations were studied in different plant species grown in five soil treatments. For either shoots or roots, a positive linear relationship was found between Sr and Ca concentrations in different plant species grown in the same soil treatment. Strontium and calcium concentrations of different species were related to the soil selectivity coefficient for Sr and Ca, defined as the ratio of CH3COONH4-extractable Sr and Ca to the ratio of Sr and Ca in the soil solution. For the species used in all soils, transfer factors (TF) for Sr, defined as the ratios of the Sr amount per g of dry plant material and the Sr amount per g of dry soil, were negatively correlated with extractable Ca of the soil. Transfer factors for Sr varied greatly among species or between roots and shoots. This variation of transfer factor was reduced when transfer factor values were divided by the shoot or root Ca concentration of each species. The proposed index TF for Sr per Ca concentration could be used to compare various soils according to their ability to supply plants with Sr when different plant species are grown in these soils.  相似文献   

13.
海南岛兴隆地区某些药用植物中的微量元素   总被引:2,自引:0,他引:2       下载免费PDF全文
本文研究海南兴隆地区12种不同类型药用植物微量元素的生物吸收系数(Ax)及其含量水平变化特性,结果表明不同科、属、种植物对同一元素的吸收量差异显著,以Mg>Al>Fe>Mn>Zn>Cu为序;同属不同品种植物在不同生境中对微量元素的生物吸收系数各有差别,海南槟榔(Ax0.30×10-6、12.51×10-6)>泰国槟榔(Ax0.29×10-6、11.59×10-6>云南槟榔(Ax0.27×10-6、11.56×10-6),元素间吸收量相比以Mo>Zn>Cu>Mn>Ni为例;同种植物不同器官微量元素的吸收量也是不同的,例如巴戟天的含量以根(218.48×10-6>叶(115.19×10-6)>茎(113.02×10-6)。植物与土壤中元素含量消长变化关系密切,相比之下,植物中Fe、Mn、Zn含量均高于Cu、Ph、Ni。绞股蓝(189.26)>巴戟天(169.04)>益智(161.70)>槟榔(155.88)。  相似文献   

14.
研究云雾山天然草地、灌草地、禁牧地、撂荒地4种恢复方式下草地各植物组分(植物地上部分、枯落物、根系)与土壤C、N、P化学计量特征及其相互关系.结果表明: 土壤与植物地上部分和根系的化学计量学特征显著相关,并且植物地上部分与根系之间P的联系比N紧密,土壤与植物地上部分和根系之间N的联系比P紧密,而土壤与枯落物、根系与枯落物的化学计量学特征相关性不显著.不同恢复方式间植物地上部分和根系总体的C、N储量无显著差异,P储量差异显著且以撂荒地最大(0.49 g·m-2),禁牧地最小(0.29 g·m-2).禁牧年限对植物和土壤的化学计量学特征影响较小;耕地撂荒恢复12年后土壤C、N(分别为9.98和1.07 g·kg-1)仍显著低于天然草地(分别为14.27和1.55 g·kg-1),两者植物化学计量特征的差异由撂荒地各植物组分P浓度高引起;由于根系生物量的稀释作用,天然草地根系N、P浓度最低(分别为6.25和0.57 g·kg-1);灌草地地上部分N、P浓度偏低(分别为12.77和 0.98 g·kg-1),但根系N、P浓度偏高(分别为9.30和0.77 g·kg-1).物种组成是影响植物生态化学计量学特征变化的主要因素,不同恢复方式间群落相似度高则整体化学计量特征差异小.  相似文献   

15.
The mean element concentration of 37 plant species followed an order as Na>K>Ca>P>S>Al>Fe>Mn in Alashan region, Nei Mongol. The greatest variation was found in Na concentration among species with variation coefficient of 1.378. Kalidium spp. plants had the highest Na concentration, while Stipa glareosa Smirn. and Cleistogenes songorica (Roshev.) Ohwi had the lowest among the species studied. The intraspecific variation coefficient was less than the interspecific variation coefficient of most elements in the same species at different sites, although the reverse was seen in a few species. Variance of concentration ratios, viz K to Ca, K to P and Ca to P was minimally, while that Na to K, Na to Ca, Na to S and S to P was greater, and the ratios of desert plant were minimal, and those of salt desert plants were maximal. The correlation analysis of element concentration in plant revealed that Fe and Al, Na and ash, and S and ash correlated at the level of 0.001, Na and S correlated at the level of 0.05. The results of clustering and ordination of 8 element concentration in 37 species showed that quantitative analyse methods can distinguish the characteristics of elements concentration in different plant families and show the characteristics of their ecological groups.  相似文献   

16.
在九龙山国家级自然保护区内, 针对濒危植物南方铁杉(Tsuga chinensis var. tchekiangensis)的分布特点, 设置了40个具有代表性的样地。采用群落分类的双向指示种分析法(TWINSPAN)进行群落类型的划分, 并在此基础上, 研究了不同群落类型下南方铁杉植株和土壤中金属元素的含量差异及其与土壤养分因子的关系。结果表明: 1) TWINSPAN分类将九龙山南方铁杉群落分为5种类型, 代表5种不同生境和物种组成的群落类型。2)不同群落类型下南方铁杉植株和土壤中的金属元素存在一定的差异, 在群落类型II和V中, 植株金属元素总量相对较高, 且K、Ca、Fe、Mg、Ba和Cr 6种元素含量也较高, 大部分土壤金属元素以群落类型II为最高。3)不同金属元素在南方铁杉植株和土壤中的含量具有很大差异, 植株中Ca、K、Mg、Fe和Mn含量较高, 土壤中Al和Fe的含量较高。4)南方铁杉不同器官金属元素的含量存在一定的差异, 各元素在不同器官中的排列顺序和变异程度不一致。5)富集系数和相关性分析表明, 南方铁杉对Mg和Zn的吸收具有相似性, 对Fe和Al的吸收也相似。6) 南方铁杉植株的大多数金属元素与土壤金属元素没有相关性, 究其原因可能是植株元素虽主要来源于土壤, 但受植物种类和生长发育状况、林地土壤类型、肥力及pH等因素的影响。  相似文献   

17.
调查和分析测定同一产区不同土壤类型的黄花蒿土壤和植株不同部位的养分含量及青蒿素含量,并对其进行相关分析和因子分析,结果表明,青蒿素含量与土壤Ca的含量有显著的正相关关系,与根N、茎N素含量以及植株地下部和地上部的N素含量比有显著的负相关关系,与茎部和叶部的N素含量比有极显著负相关关系;黄花蒿植株叶片的N含量与土壤P含量有显著的正相关关系;影响青蒿素含量的主要因子是黄花蒿植株体内的养分含量,其次是土壤的养分含量以及土壤和植株等综合因子。通过施肥、适当补充土壤中的Ca和P素营养,改善土壤养分状况等各种途径来调节植株体内的养分,降低地下部和地上部的N素含量比值,茎叶部N素含量比值,提高青蒿素的含量,增施K肥,有利于黄花蒿的生长。  相似文献   

18.
中卫山羊核心产地种子植物生活型和区系地理特征   总被引:1,自引:0,他引:1  
对中卫山羊的核心产区——宁夏香山荒漠草原区的植物物种生活型和区系地理特征进行初步统计,结果表明所有调查的种子植物区系组成具有明显的温带性质,并且植物区系地理成分组成的脆弱性是本地植物区系的显著特点。植物生态、生活型中以地面芽植物、旱生及一年生植物较多,体现了干旱环境、山地微地形及长期的放牧干扰下物种种系发育的特征。  相似文献   

19.
土壤-植物系统是生物圈的基本结构单元,土壤与植物之间存在密切的相互反馈。土壤退化导致植物面临各种非生物胁迫,植物的生理代谢遭到干扰,养分获取受到抑制。蚯蚓被称为“生态系统的工程师”。蚯蚓能够通过调控土壤物理-化学-生物学特性,改良退化土壤(盐碱土、重金属和有机污染物污染土壤),缓解植物所受胁迫,增加土壤养分有效性,促进植物生长,并通过自身分泌的信号物质提高植物的抗逆性。蚯蚓对土壤-植物系统的生态修复作用,对于改善植物生长环境、维持土壤生态系统健康和稳定具有重要意义。  相似文献   

20.
While methodology is transferable from one laboratory to another, an exact transfer does not usually occur and even a nearly exact transfer of methods does not always result in repeatable data. Researchers should not expect that an effort to duplicate a published procedure will necessarily lead to identical results.In attempting to transfer rice tissue culture methods between laboratories in Fort Collins, Colorado, USA and Bangkok, Thailand, we discovered that a combination of the methods of each laboratory produced the best results in term of callus productions and plant regeneration. In the experiments reported here, the type of culture vessel used and the geographical location were also important variables.Supported by the USAID/Cooperative Agreement No DAN-4137-A-00-4053-00.  相似文献   

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