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1.
通过形态、扫描电镜观察及人工控制授粉等方法对温室环境中的睫毛萼凤仙花(Impatiens blepharosepala Pritz. ex Diels)、绿萼凤仙花(I. chlorosepala Hand.-Mazz.)、菱叶凤仙花(I. rhombifolia Y. Q. Lu et Y. L. Chen)等凤仙花属3种植物的开花物候、花部性状以及繁育系统进行探究。结果显示:3种植物的开花物候依据花部形态变化可分为6个时期,各植物花期存在部分重叠;花部性状、部分繁育指标、花粉粒和子房微形态等方面均存在部分差异;3个物种的花粉生活力与柱头可授性变化趋势在整体上呈单峰型;3种植物的繁育系统均为兼性异交,其具体特征为自交亲和、需要传粉者;花蜜报酬满足小体型昆虫的传粉需要;3个物种的6种控制授粉处理中对照处理结实率低于3种人工授粉处理结实率,且不存在自花授粉和无融合生殖的现象;3种处理中人工异株异花授粉处理结实率最高,人工同株异花授粉处理结实率最低。  相似文献   

2.
报道了云南省凤仙花科(Balsaminaceae)凤仙花属(Impatiens L.)植物2新记录,即睫毛萼凤仙花(I.blepharosepala Pritz.ex Diels)和红雉凤仙花(I.oxyanthera Hook.f.),并提供了形态描述及其图片,凭证标本保存于重庆三峡学院生命科学与工程学院植物标本馆。该报道的睫毛萼凤仙花花色为白色,红雉凤仙花植株茎、叶皆被微柔毛,茎有分枝,小枝细,丰富了2个物种的形态描述。  相似文献   

3.
腊叶标本的妙制法在生物新教材中介绍的腊叶标本制作的方法是:用纸条把干燥的标本固定在台纸上,贴上标签,贴上盖纸。此法有不足之处:(1)标本固定得不牢固,又影响美观。(2)标本易潮、易干燥、易损伤、易变色,影响使用价值和时间。(3)处理标本时有毒害的物质...  相似文献   

4.
为探究凤仙花近缘种植物的细胞学和微形态学方面的亲缘关系,该文选取荔波凤仙花(Impatiens liboensis)及近缘种赤水凤仙花(I.chishuiensis)和管茎凤仙花(I.tubulosa)的根尖和叶表皮为实验材料,采用体细胞染色体常规压片法和叶表皮光学显微镜观察法对凤仙花近缘种植物进行染色体及叶表皮特征研...  相似文献   

5.
牛奶子花粉形态特征与生活力测定   总被引:1,自引:0,他引:1  
马晓丽  韩榕 《植物研究》2010,30(1):8-11
采用两种扫描电镜样品制备技术制备牛奶子花粉,扫描电镜观察其形态,研究结果表明:经自然干燥法制样,牛奶子花粉外观变形严重;采用固定—脱水制样,花粉外形保持良好,牛奶子花粉近球形,极面观钝三角圆形,具3沟,表面具脑纹状雕纹。采用I2-KI染色法测定牛奶子花粉开花后不同时间的生活力,结果表明:牛奶子花粉生活力在开花初较高,并在开花后36h内维持在80%以上,之后迅速下降,但在花期末仍有部分花粉具有生活力。  相似文献   

6.
应用常规高真空扫描电子显微镜观察生物样品必须经过脱水和干燥处理,但无论采用临界点干燥还是冷冻干燥方法,都存在样品表面不同程度失真的问题。植物高水分、富含淀粉组织样品经处理后,容易出现淀粉流失、细胞壁变形等现象,从而造成扫描图像粗糙,无法获得真实的细胞内部结构。本文通过对CO_2临界点干燥、化学固定样品冷冻干燥和新鲜样品冷冻干燥3种扫描电镜样品制备技术中后期制样进行机械断裂和液氮脆断改进,优化出两种植物高水分、富含淀粉组织的扫描电镜样品制备方法:(1)样品首先进行FAA化学固定,经冷冻干燥后用液氮脆断,对断面喷金镀膜和扫描电镜观察。利用该方法所得细胞结构完整,细胞壁整齐,淀粉粒和蛋白轮廓明确,可用于分析淀粉粒和蛋白颗粒在细胞内的分布。(2)新鲜样品直接进行冷冻干燥,经液氮脆断后对断面喷金镀膜和扫描电镜观察。利用该方法所得细胞壁整齐,淀粉粒轮廓更清晰,并且无蛋白颗粒干扰,用于分析淀粉粒在细胞内的分布更加理想。  相似文献   

7.
韦毅刚 《生命世界》1992,19(4):45-45
目前国内普遍采用的干燥植物腊叶标本的方法,主要有用草纸吸水干燥和瓦楞纸烘烤两种。前者压制而成的标本质量较好,却十分费时费工,后者虽大大提高了效率,但瓦楞纸用不了多久就会变形,而且容易失火,也并不十分理想。现介绍一种较好的干燥腊叶标本的方法。制备长44厘米,宽30厘米的铝制波纹板若干,将采来的新鲜标本夹压在报纸中,用铝板将其上下夹住,  相似文献   

8.
报道了产自中国云南的凤仙花属一新记录种:三瓣凤仙花(Impatiens tripetala Roxb. ex DC.)。该种原产于孟加拉国和印度,本次在中国为首次发现。该种与缅甸凤仙花(I. aureliana Hook. f.)外形相似,但前者花单生或簇生,唇瓣囊状,深10~17 mm,距长5.5~8 mm,蒴果光滑,以此与后者相区别。凭证标本存放于湖南师范大学植物标本馆(HNNU)。  相似文献   

9.
林祁 《生物学通报》1997,32(4):40-41
一株植物或者植物体的一部分经过压制干燥以后称为腊(读音xi)叶标本。腊叶标本经过装订可以收藏在标本柜中长期保存,为生产、科研和教学服务。目前,我国各地中学已经普遍开展自制腊叶标本,为生物学教学眼务。由于各所学校采用的装订方法和用具不同,使得标本装订后质量各异。为了提高腊叶标本的装订质量,在此介绍2种较流行的腊叶标本装订法。1胶粘装订法该方法所需用具较多,装订速度快,是国际上较流行的腊叶标本装订法。1.工装订用具台纸垫衬标本用,标本装订在台纸上。台纸要求坚韧,通常用白卡纸制作,大小为8开,约39x28cm。标…  相似文献   

10.
孟雷  朱相云 《西北植物学报》2006,26(12):2574-2579
在考证了模式标本和查阅了大量腊叶标本的基础上,结合野外居群生物学调查工作,作者对分布于蒙古和我国境内的Glycyrrhiza alaschanicaGrankina、G.gobicaGrankina和G.soongoricaGrankina 3种甘草做了归并处理。认为它们属于乌拉甘草(G.uralensisFisch.ex DC.)的变异类型,均处理为乌拉甘草的异名。  相似文献   

11.
Dried plant herbarium specimens are potentially a valuable source of DNA. Efforts to obtain genetic information from this source are often hindered by an inability to obtain amplifiable DNA as herbarium DNA is typically highly degraded. DNA post-mortem damage may not only reduce the number of amplifiable template molecules, but may also lead to the generation of erroneous sequence information. A qualitative and quantitative assessment of DNA post-mortem damage is essential to determine the accuracy of molecular data from herbarium specimens. In this study we present an assessment of DNA damage as miscoding lesions in herbarium specimens using 454-sequencing of amplicons derived from plastid, mitochondrial, and nuclear DNA. In addition, we assess DNA degradation as a result of strand breaks and other types of polymerase non-bypassable damage by quantitative real-time PCR. Comparing four pairs of fresh and herbarium specimens of the same individuals we quantitatively assess post-mortem DNA damage, directly after specimen preparation, as well as after long-term herbarium storage. After specimen preparation we estimate the proportion of gene copy numbers of plastid, mitochondrial, and nuclear DNA to be 2.4-3.8% of fresh control DNA and 1.0-1.3% after long-term herbarium storage, indicating that nearly all DNA damage occurs on specimen preparation. In addition, there is no evidence of preferential degradation of organelle versus nuclear genomes. Increased levels of C→T/G→A transitions were observed in old herbarium plastid DNA, representing 21.8% of observed miscoding lesions. We interpret this type of post-mortem DNA damage-derived modification to have arisen from the hydrolytic deamination of cytosine during long-term herbarium storage. Our results suggest that reliable sequence data can be obtained from herbarium specimens.  相似文献   

12.
The pollen of 32 species of Lysipomia was examined by light, scanning, and transmission electron microscopy. Two pollen types occur in the genus: 3-colporate and 6-colporate. The 3-colporate condition occurs in only two species, L. laciniata and L. pumila. The remaining 30 species are 6-colporate, a condition known from only one other genus in the Campanulaceae. Surface sculpturing among the species is uniformly striate. Pollen shape was highly variable within a single individual in comparisons of pollen gathered from herbarium specimens, FAA preserved material collected in the field, and fresh pollen from cultivated individuals grown from seed. Shape may change from oblate spheroidal to subprolate as a result of drying time and temperature, and should not be used as a morphological character in systematic studies if infraspecific variation is seen. When fresh or preserved pollen is not available, rehydrated pollen should be compared to reduce the possibility of inadvertent artifact production confounding the analysis of morphological data.  相似文献   

13.
新疆蒲公英属有性生殖与无融合生殖植物的调查研究   总被引:3,自引:0,他引:3  
以新疆22种蒲公英的186份腊叶标本为材料,观察统计了每份标本的花粉败育率、花粉粒大小变异的标准方差。标准方差小于3、败育率小于20%的花粉PR变异型,是有性生殖植物的特征;标准方差大于3、败育率大于40%的花粉PS变异型,是无融合或兼性无融合植物的特征;不产生花粉的PA变异型,则是雄性不育植物的特征。在所观察的标本中,有4种蒲公英植物出现了有性生殖个体,其余为无融合或兼性无融合类。此外,还就蒲公  相似文献   

14.
A new method which utilises confocal optical imaging has been developed which can be expected to improve grass pollen analysis. Confocal microscopy, in reflection mode, was used to examine the exine morphology of unacetolysed pollen grains from the following species of common wild grasses: Paspalum dilatatum, Setaria gracilis, Bromus catharticus, Daclylis glomerata, Lolium perenne, Poa pratensis, and Phalaris aquatica. Variations in the surface texture patterns, similar to those hitherto only seen by scanning electron microscopy, were visualised. In contrast to the latter method, specimen preparation for this confocal microscopy based technique was characterised by its simplicity, permitting the use of fresh and chemically untreated pollen grains. This confocal imaging technique, with its capacity for optical sectioning of specimens, offered the additional advantage of allowing the examination of the sub‐surface exine layers as well as the surface morphology of the pollen grains. Furthermore, three‐dimensional reconstruction of these optical sections enabled visualisation of the identified sculptural and structural exine elements and layers. A number of differences in these patterns were found, which indicate that confocal microscopy, in combination with image analysis, may enable finer taxonomic distinctions to be made than those currently provided by other light microscope based methods.  相似文献   

15.
Herbarium specimens are a treasure trove for biochemical studies. However, this implies understanding of the chemical changes during the drying and storage of the specimen. We compared herbarium specimens at different ages and fresh samples of four mushroom species (Kuehneromyces mutabilis, Hypholoma capnoides, Kuehneromyces lignicola, Hypholoma fasciculare) of two genera in the family Strophariaceae by using proton nuclear magnetic resonance (1H NMR) spectroscopy combined with principal component analysis (PCA). 25 metabolites were identified. No significant alterations were found between herbarium samples at different ages, suggesting that they are stable enough for comparative studies. The most dominant differences between fresh and herbarium samples was that sugars such as α-α-trehalose, and fumaric and malic acids were more abundant in fresh fungi. Total contents of fatty and amino acids, uracil and γ-aminobutyric acid (GABA) were higher in herbarium specimens. In addition, pyroglutamic acid was observed only in Kuehneromyces mutabilis and fasciculic acid E in Hypholomafasciculare. Hence, based on results of the studied taxa, we conclude that NMR metabolomics can be used for both fresh and dried mushrooms when such alterations are properly addressed.  相似文献   

16.
In northwestern Himalayan species of Impatiens, the pollen grains at shedding possess a crescent shaped generative nucleus in prometaphase from which the chromosome number is easily determined. The fresh or fixed pollen grains are studied by the usual aceto-carmine squash method. The generative nucleus generally remains in the same state in pollen of the herbarium specimens. Anthers from such material are soaked overnight in a saturated solution of iron acetate in 45% acetic acid, rinsed and squashed in dilute aceto-carmine. Preparations are heated several times to boiling. Reliable counts of chromosomes have been made from such slides.  相似文献   

17.
植物标本是分类学、生态学和分子生物学最重要的凭证之一。标本的采集和鉴定信息需清晰、准确、美观地展示和保存于标本标签中, 不能有歧义以及拼写错误。在标签的制作过程中, 数据输入的方式要简单、直接, 标签文件生成过程中最好能自动分析错误, 且在打印之前要便于修改和调整。本文探讨了打印植物标本标签的若干原则以及注意事项, 并介绍了用R语言编写的herblabel程序包生成植物标本标签以及鉴定标签的过程。herblabel程序包基于Darwin Core和CVH5.0数据交换标准, 可快速批量生成几种样式的RTF标签, 且标签简洁、美观, 易于编辑。herblabel程序包具有检查地点完整程度, 学名拼写和接受状态, 科、属在APG等新系统下的对应关系等功能, 可有效减少数据录入过程中产生的错误。此外, 本程序包在打印标签时使用的是基于Darwin Core标准保存的标本数据库, 不仅方便统计和管理, 也可以直接用于全球生物多样性信息网络(GBIF)数据共享或者数字植物标本馆的建设。该程序包可显著提高植物标本馆标本制作、管理和信息录入的工作效率, 减轻工作人员的负担, 并在植物生物多样性编目中发挥重要作用。  相似文献   

18.
Background and AimsHerbaria were recently advertised as reliable sources of information regarding historical changes in plant traits and biotic interactions. To justify the use of herbaria in global change research, we asked whether the characteristics of herbarium specimens have changed during the past centuries and whether these changes were due to shifts in plant collection practices.MethodsWe measured nine characteristics from 515 herbarium specimens of common European trees and large shrubs collected from 1558 to 2016. We asked botanists to rank these specimens by their scientific quality, and asked artists to rank these specimens by their beauty.Key ResultsEight of 11 assessed characteristics of herbarium specimens changed significantly during the study period. The average number of leaves in plant specimens increased 3-fold, whereas the quality of specimen preparation decreased. Leaf size negatively correlated with leaf number in specimens in both among-species and within-species analyses. The proportion of herbarium sheets containing plant reproductive structures peaked in the 1850s. The scientific value of herbarium specimens increased until the 1700s, but then did not change, whereas their aesthetic value showed no systematic trends.ConclusionsOur findings strongly support the hypothesis that many characteristics of herbarium specimens have changed systematically and substantially from the 16th to 21st centuries due to changes in plant collection and preservation practices. These changes may both create patterns which could be erroneously attributed to environmental changes and obscure historical trends in plant traits. The utmost care ought to be taken to guard against the possibility of misinterpretation of data obtained from herbarium specimens. We recommend that directional changes in characters of herbarium specimens which occurred during the past 150‒200 years, primarily in specimen size and in the presence of reproductive structures, are accounted for when searching for the effects of past environmental changes on plant traits.  相似文献   

19.
Question: How accurately do Amazonian montane forest pollen spectra reflect the vegetation? Can compositional changes observed in the vegetation along environmental gradients be identified in the pollen spectra? How well do herbarium collection data and bioclimatic envelopes represent abundance changes along elevation gradients? Location: Amazonian montane forests, Peru. Methods: Moss polsters collected along five altitudinal transects spanning over 3000 m a.s.l. were used to characterize pollen spectra. Vegetation plot data from a network of 15 1‐ha permanent plots were used to correlate pollen spectra with present‐day vegetation. Probability density functions (PDFs) fitted to pollen and plot data allowed comparisons using Spearman correlation coefficients. Ordination analyses were used to summarize changes in pollen spectra. Correlations between pollen‐based PDFs and previously‐published herbarium collection PDFs were also evaluated. Results: Pollen spectra closely reflected changes in species composition along elevation gradients. A mid‐elevation shift in pollen spectra was identified using ordination analyses. Pollen spectra from the driest forest in our data set were statistically different from those of wet forests. Pollen abundance PDFs along the altitudinal gradient were significantly correlated (P<0.01) with PDFs fitted to plot abundance, basal area and herbarium collection data for ten out of 11 taxa analysed. Conclusions: Pollen spectra closely reflected the vegetation composition of Amazonian montane forests. The differentiation of pollen spectra from dry localities showed the potential of genus‐level pollen data to reflect precipitation gradients. Pollen spectra also reflected mid‐elevation compositional changes well along the lower elevation limit of ground cloud formation. Despite collection biases, herbarium‐based bioclimatic envelope PDFs also represented well forest compositional changes along elevation gradients.  相似文献   

20.
Five published DNA extraction protocols were compared for their ability to produce good quality DNA from fresh and herbarium leaves of several species of the genus Dalbergia. The leaves of these species contain high amounts of secondary metabolites, which make it difficult to perform a clean DNA extraction and thereby interfering with subsequent PCR amplification. The protocol that produced the best DNA quality in most of the Dalbergia species analyzed, utilizes polyvinylpyrrolidone to bind the phenolic compounds, a high molar concentration of NaCl to inhibit co-precipitation of polysaccharides and DNA, and LiCl for removing RNA by selective precipitation. The DNA quality of herbarium specimens was worse than that for fresh leaves, due to collecting conditions and preservation of samples. We analyzed 54 herbarium specimens, but the recovered DNA allowed successful PCR amplification in only eight. For the genus Dalbergia, the herbarium is an important source of material for phylogenetic and evolutionary studies; due to the occurrence of the different species in various geographical regions in Brazil, it is difficult to obtain fresh material in nature. Our results demonstrated that for Dalbergia species the methods used for the collection and preservation of herbarium specimens have a mayor influence on DNA quality and in the success of phylogenetic studies of the species.  相似文献   

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