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1.
桦木科植物的系统发育和地理分布(待续)   总被引:6,自引:1,他引:5  
本文对桦木种植物的研究历史作了详细的总结。在钻研文献的基础上,补充了部分系统学资料,使得花序、花,花粉、叶表皮等各类性状能够在属间进行比较。根据外类群比较、和谐性分析等原则确定了性状的演化极性,利用最大同步法和最小平行演化法对桦木科植物进行了分支分析。对各属的现代分布和地史分布作了描述,在此基础上,讨论了桦木科植物的分布中心、起源地、起源的时间和散布的途径。作者试图回到遥远的晚白垩纪和早第三纪,从描绘桦木科植物起源和早期分化的古地理和古气候背景人手,分析了在这种背景下桦木科植物所发生的空间辐射以及植物体本身所产生的形态进化,以求得对桦木科植物起源、散布和分化作出比较合理的解释。最后对桦木科组以上的等级作了分类处理。  相似文献   

2.
目的:依据ITS序列分析新疆濒危植物盐桦的系统发育.方法:运用PCR直接测序法,对珍稀濒危植物盐桦(Betulahalophila)的nrDNA的ITS区(包括ITS-1,5.8SrDNA和ITS-2)进行序列测定,并与GenBank中提取的17种桦木科桦木属植物的ITS区序列进行了组合分析.结果:盐桦的ITS序列和已公布的17种桦木科桦木属植物的ITS区序列差别不大,同源性在99.67%~99.01%之间.采用clustalx软件对盐桦和17种桦木属植物的ITS区序列进行系统发育分析,构建了桦木属植物的ITS分子系统树,18种桦木科桦木属植物形成三个分支,盐桦与Betula alnoides、Betula populifolia、Betula pubescens同为一支.结论:盐桦在桦木科桦木属内有独特的分类地位.  相似文献   

3.
桦木科植物叶表皮的研究   总被引:34,自引:4,他引:30  
本文利用光学显微镜及扫描电镜观察了桦木科6属、38种植物的叶表皮。发现该科植物成熟叶片的气孔器有四种类型:即无规型、轮列型、不典型辐射型和短平列型,叶表皮性状及性状状态对于桦木科植物属的确定和族的划分具有重要的分类学价值。在确定叶表皮性状的演化趋势时,综合了其他方面的研究成果(如Abbe,1935,1974;Brunner和Fairbrothers,1979;Hall,1952;Kikuzava,1982;Kuprianova,1963),并且发现叶表皮形态对于揭示桦木科植物的属间演化有较大的参考价值。作者认为:叶表皮特征支持将桦木科分成两个族;气孔器无规则型、气孔器外拱盖单层、气孔器在保卫细胞极区无”T”型加厚以及下表皮细胞垂周壁平直为原始的叶表面性状;下表皮细胞垂周壁具波纹和气孔器为不典型辐射型等特征仅发现于榛属、虎榛子属,铁木属和鹅耳枥属,从而将榛族与桦木族分开;桦木族包括桦木属和桤木属,由于具有较多的原始性状而比榛族原始,在榛族中,鹅耳枥属最为特化(见图1)。  相似文献   

4.
论山毛榉科植物的系统发育   总被引:10,自引:2,他引:8  
本文运用分支分类学方法,对山毛榉科植物进行了系统发育的分析。山毛榉科作为单元发生群包括柯属、锥属、粟属、三棱栎属、水青冈属和栎属。桦木科和南山毛榉属被选择作为外类群。对大量的性状进行评估之后,选择了25对性状作为建立数据矩阵的基本资料。性状极化以外类群比较为主,同时也采用了化石证据和通行的形态演化的基本原则。数据矩阵由7个分类群、2个外类群和25个性状组成。采用最大同步法、演化极端结合法和综合分析法对该数据矩阵进行了分析。在得到的3个树状分支图中按照最简约的原则,选出演化长度最短的谱系分支图作为本文讨论山毛榉科属间的系统演化关系的基础。关于山毛榉科植物的系统发育,作者的观点如下:(A)现存的山毛榉科的6个属形成了4条平行进化的分支路线,它们分别被处理作4个亚科,即:栗亚科,三棱栎亚科,水青冈亚科和栎亚科;(B)平行进化是山毛榉科植物系统发育过程中的主要形式。生殖过程中的一些特征,如:果实第二年成熟,胚珠通常败育等,是影响山毛榉科植物属间基因交流的主要原因。在现存的山毛榉科植物中,柯属是最原始的类群。三棱栎属和锥属的起源也较早,而栗属、水青冈属和栎属是特化的类群。  相似文献   

5.
秦岭种子植物区系科的组成、特点及其地理成分研究   总被引:10,自引:1,他引:9  
张秦伟 《植物研究》2001,21(4):536-545
秦岭种子植物区系组成丰富, 共有种子植物198 科、1007 属、3446 种, 区系组成的大科及主要科共16 科, 占秦岭种子植物总数属的50.05%, 总种数的57.25%, 它们构成了秦岭植物区系组成的基本框架, 就其性质来讲, 绝大多数为温带性质。松科、壳斗科、桦木科、杨柳科、蔷薇科、杜鹃花科、禾本科、莎草科等是秦岭植被的区系组成的优势科, 从地理成分上来分析, 本区科的分布型可以划分为世界或亚世界分布科、热带分布科、温带分布科、间断分布科以及东亚和中国特有科, 其区系的起源则有明显的古老性。  相似文献   

6.
桦木科植物的花粉形态研究   总被引:10,自引:1,他引:9  
对桦木科植物(包括6属36种)的花粉进行了光学显微镜、扫描电镜和透射电镜观察;系统地描 述了各属的花粉形态,划分了三种花粉类型,即桦木型、榛型、鹅耳枥型,并澄清了前人在带状加厚、孔盖和颗粒层等概念上的模糊认识。根据花粉的形态,作者不支持Hutchinson(1973)和Dahlgren(1983)把桦木科分成两个科,即榛科(包括榛属、虎榛子属、鹅耳枥属和铁木属)和桦科(包括桤木属和桦木属);而同意Abbe(1974)将桦木科作为三个族来处理,并且认为虎榛子属应该从榛族分出,置于鹅耳枥族;尽管作者不支持Kuprianova(1963)将桦木科划分为三个科,但本文所提出的三个族与Kuprianova的三个科只是分类等级上的差异。  相似文献   

7.
桦木科植物的系统发育和地理分布(续)   总被引:16,自引:1,他引:15  
地 理 分 布 以上,我们对桦木科植物进行了分支分析,关于该科六属之间的关系有了比较清晰的认识,这是地理分布分析的基础之一。 经典分类和古植物方面的研究是地理分布分析的另外两类基础性资料。早在1904  相似文献   

8.
赤瓟属的系统学研究   总被引:3,自引:0,他引:3  
采用比较形态学方法,本文首次描述和记录了该属植物的传粉生物学特征以及传粉媒介,并讨论了造成该属某些种结实率低的原因。本文还同存赤BO属及其近缘属植物的分布式样以及它们的属下分类群的系统演化式样,确定了中国的横断山系和大巴山系地区是该属植物的现代分布中心和分化中心,而中国云南南部和中南半岛北部地区的性山地雨林是该属植物的起源中心。在综合大量资料的基础上,本文对赤Bo属作了分类学修订。确认该属有22种  相似文献   

9.
新疆发现一种抗盐桦树   总被引:1,自引:0,他引:1  
王健 《生命世界》2003,(6):12-13
1956年9月11日,著名植物分类学家秦仁昌教授,来到新疆阿勒泰县的巴里巴盖进行野外采集,在一片含盐度极高的沼泽地里,他发现了一株桦木属植物,并采下一号标本(秦仁昌3151)。根据该植物的外部形态特征,特别是果苞的性状。与新疆分布的其他几种桦木属植物容易区别,再加上它的生境为盐沼泽地带,故把这种植物定名为桦木属中的  相似文献   

10.
桦木科植物花柱适应风媒传粉的特征   总被引:1,自引:0,他引:1  
植物体为适应自己的传粉系统, 表现出高度的适应特征。风媒花植物为适应风传播花粉, 要形成特殊的结构, 以扩大接受花粉粒的面积。利用扫描电镜观察了桦木科(Betulaceae)6属18种植物花柱的形态及花粉粒在花柱上的萌发过程, 探讨了桦木科植物花柱适应风媒传粉的特征。结果表明, 桦木科植物的二心皮(铁木、云南鹅耳枥稀为三心皮)雌蕊具柱状花柱, 柱头不发达, 花柱表皮细胞长条状, 纵向排列紧密。传粉时, 花柱表皮细胞能执行柱头的功能, 接受花粉粒, 为花粉粒萌发提供场所和萌发条件。桦木科植物花柱有2种类型: 一种是花柱表皮细胞能形成乳突, 花粉管经乳突细胞进入花柱; 另一种是花柱表皮细胞不形成乳突, 花粉管经过花柱表皮细胞或胞间隙进入花柱。无论花柱表皮细胞是否形成乳突, 乳突的形态、大小以及花粉管和乳突的结合方式等在族间、属间、属内种间存在差异。与基部被子植物相比, 桦木科植物的花柱呈现适应风媒传粉的进化特征。桦木科植物花柱表皮细胞形成的乳突与基部被子植物柱头乳突功能相同, 是桦木科植物风媒传粉的适应策略。  相似文献   

11.
In the present thesis, a detailed review of the literature was given on the Betulaceae. Some new data was provided based on the author’s studies in order to analyze various characters, such as inflorescence, flower, pollen and leaf epidermis, among the genera treated. The polarity of the characters was determined according to the criteria of outgroup comparison and compatibility analysis. A cladistic analysis was made using the methods of Maximal Same Steps and Minimal Parallel Evolution developed by Xu (1993). The generic distributions in both modern and fossil times were outlined, and their distribution center, place and time of origin and the way of dispersal were discussed. An attempt was made to discuss early differentiation, geographical radiation and morphological evolution of the family on the background of paleogeography and paleoclimatology, tracing back as far as the Late Cretaceous and Early Tertiary. Finally, supraspecific taxa, from section to tribe, were systematically arranged.  相似文献   

12.
Forty-two morphological and eighty chemical (phenolic) characters were employed on a numerical taxonomic study of the genus Platanus. Ten taxa were used for morphological study, and nine were available for chemical study. UPGA was employed for cluster analysis; correlation coefficients served as a measurement of the similarity between each OTU-pair. Comparison was made for phenograms and graph diagrams of nine taxa based on morphological characters with those based on chemical characters. It has been found that the two agree with each other in many respects. Correlation coefficient between similarity matrices based on morphological and chemical characters is 0.573. The result generally supports the belief that taxa closely related on morphological grounds are similar biochemically. A systematic consideration of the genus has been made, based on the information available.  相似文献   

13.
No qualitative cladistic analysis has been performed previously for the subfamily classification of Pompilidae (Hymenoptera). In 1994 Shimizu proposed six subfamilies, but their validity and relationships remain inconclusive. The objective of this study was to perform a quantitative analysis of phylogenetic relationships of the Pompilidae, with emphasis on testing the validity of proposed subfamilies. Two cladistic analyses were performed based on morphological evidence. First, a maximum-parsimony analysis of Shimizu's original morphological data matrix (72 taxa by 54 characters) was conducted, with the data subjected to a heuristic search for the first time with phylogenetic software. The resulting strict-consensus cladogram yielded a monophyletic Ceropalinae that was sister group to a large polytomy containing members of the remaining five subfamilies. In a second analysis, several of Shimizu's characters were re-examined, and new characters and more taxa were added to the data set. Terminal taxa were coded as species rather than as generic abstractions, and 20 additional morphological characters were introduced. The analysis was based on 77 morphological characters derived from the adults of 84 taxa. This second analysis suggested that Notocyphinae sensu Shimizu (1994) was nested within Pompilinae and that Epipompilinae sensu Shimizu (1994) was nested within Ctenocerinae; neither should retain their status as a separate subfamily. Lastly, Chirodamus s .s., which historically has been a member of the Pepsinae, is placed within the Pompilinae with reservations rather than erecting a new subfamily. After these allowances were made, a strict consensus tree gave the following relationships: (Ceropalinae + (Pepsinae + (Ctenocerinae + Pompilinae))).  相似文献   

14.
A preliminary cladistic analysis was carried out on the 49 currently recognised genera of the order Trypanorhyncha. Forty-four characters were analysed; a functional outgroup was used for scolex and strobilar characters, while Nybelinia was utilised to polarise characters related to the rhyncheal system. Eight well-resolved clades were evident in the resultant cladogram, which is compared with existing phenetic classifications. An analysis of families resulted in a similar clustering of taxa to that observed in the case of the genera. The results suggest that two key characters used in existing classifications, namely the presence of sensory fossettes on the bothridia and the development of atypical heteroacanth and poeciloacanth armatures from typical heteroacanth armatures, have occurred on several occasions. Some clades provide support for the arrangements used in current classifications. Suggestions are made for future avenues of research which might provide more robust phylogenetic data for the Trypanorhyncha.  相似文献   

15.
Ian  Abbott 《Journal of Zoology》1978,184(1):119-125
Uni- and multivariate analyses were made of nine morphological characters on three species of finches Nesospiza acunhae (Inaccessible, Nightingale), N. wilkinsi (Nightingale) and Rowettia goughensis (Gough). The results of the univariate analysis were used to test four predictions about morphological changes with altered competitive backgrounds. Finch species that occur alone on an island or on an island where other finch species are rare have longer characters and more variable character distributions.
A multivariate analysis of six bill characters showed that the bill of Rowettia is more similar to that of acunhae than either is to wilkinsi. A multivariate analysis on wing length, tarsus length and hallux length shows that Rowettia is morphologically closer to wilkinsi than it is to acunhae. It is suggested that nothing is gained by treating the Gough I. finch as belonging to a monotypic genus.  相似文献   

16.
采取脉络法,对柳属(Salix)繁柳组(Sect.Denticulatae C.K.Schneid.)17种及1变种进行叶片脉序观察。结果表明:繁柳组植物叶脉序类型均为直行羽状脉,表现出较高的一致性。该组植物均有二级间脉,但类型各有不同;三级脉及较高级脉序大体有三种类型;网眼发育完善或不完善;盲脉偶有不分枝;不同种之间网眼的发育以及盲脉分枝具有显著差异,是有价值的分类性状。根据聚类分析,繁柳组植物叶脉序分为两种类型:草地柳(S.praticola Hand.-Mazz.ex Enander)类型及腹毛柳(S.delavayana Hand.-Mazz.)类型,研究结果与形态学结果基本一致,但叶脉序提供了新的分类学性状,可为柳属植物疑难种的分类寻找新的依据。  相似文献   

17.
海南省兴隆地区菠萝蜜种质资源调查与评价   总被引:1,自引:0,他引:1  
对海南省兴隆地区菠萝蜜种质的分布、生境、花果期、栽培历史以及主要性状等进行了调查,并对菠萝蜜的农艺性状、果实品质等进行了综合评价.  相似文献   

18.
加工番茄丰产品种模式化选择的研究   总被引:1,自引:0,他引:1  
以20个制酱专用型番茄品种(系)为试材,对产量及其构成因素、生育期性状、形态性状进行了典型相关分析;针对新疆自治区的生态条件、栽培技术和品种资源现状,提出了制酱专用型番茄丰产品种的模式;并对丰产品种的生育期因子和形态性状进行了优化,以期为加工番茄的品种选择提供理论依据.  相似文献   

19.
陈影  姚方杰  张友民  方明 《菌物学报》2014,33(5):984-996
在木耳栽培种质资源农艺性状调查的基础上,应用数量分类学中的Q型聚类分析法对20个木耳菌株进行分类研究,并对14个农艺性状进行R型聚类分析和主成分分析。结果表明:Q型聚类将20个木耳菌株在欧氏距离6.29处依据子实体朵型性状分为簇生型菌株和菊花型菌株两大类群,菊花型类群在欧式距离4.79处依据生育期性状的原基发生类型划分为分散型和集中型两个亚群;R型聚类表明菌丝体性状(1个)、生育期性状(2个)、子实体性状(8个)等11个农艺性状间相关性较强;主成分分析中,发现子实体背面皱褶、耳片数、原基发生时间、子实体朵型、干耳背面颜色等5个性状是14个农艺性状的第1主成分,贡献率高达62.26%,把第1主成分命名为朵型-生育期构成因子,作为种质评价的指标。  相似文献   

20.
A numerical taxonomic study of the angiosperm family Limnanthaceae is presented. The 21 OTUs include all taxa recognized in a recent monograph of Limnanthes (Mason, 1952), plus Floerkea proserpinacoides, two undescribed Limnanthes species, and two artificial interspecific F1 Limnanthes hybrids. One species (L. montana) was treated as two OTUs: measurements for one OTU were taken from field collections and for the other, from garden-grown plants. A maximum of 35 characters was used in the numerical analyses. Raw data for each character were given equal weighting by condensation. Coefficients of resemblance were established using the mean character difference (MCD) method. Tryon's clustering technique (called key communality cluster analysis) was used. Three numerical analyses of Limnanthaceae were made: one with all 35 characters (T analysis), one with 18 floral characters (F analysis), and one with 17 pre- or post-anthesis or vegetative characters (V analysis). Relative positions of OTUs in the T and F analyses are substantially different from those in a conventional taxonomic treatment of the family. The V analysis shows many differences from the T and F analyses. In all analyses the two OTUs representing L. montana were closer to other OTUs than to each other. The two hybrid OTUs showed greater resemblance to one parent than to the other and in two analyses one hybrid was not intermediate between the parents. Similarities between the T and F analyses are explained on the basis of the predominance of floral characters in both. The differences between these two analyses on the one hand and the V analysis and phylogenetic arrangement of the family on the other are attributed to parallelisms in the evolution of floral characters associated with iucreasing autogamy in each of the two phyletic lines in the family. Analyses emphasizing floral characters will place evolutionarily remotely related outcrossing OTUs together and unrelated, autogamous OTUs together. Using characters that are mostly unassociated with the breeding system the positions of OTUs in a numerical analysis are similar to their positions in a phylogenetic arrangement. The V analysis agrees best with suggestions concerning phylogenetic affinities among the taxa in the family, and provides a useful context for the generation of further evolutionary hypotheses.  相似文献   

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