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1.
TheMelampyrum sylvaticum group is a heterogeneous group at the inter- and infra-specific level. A wide range of morphological characters was examined on specimens collected for this study. The corolla size, the corolla colour and the anther length are considered the most important morphological characters at the interspecific taxonomic level. The morphological and molecular variation of theMelampyrum sylvaticum group in the Sudeten, Alps and Carpathians was analyzed. The morphometric study of European populations ofMelampyrum sylvaticum group partly clarified the pattern of the variation of selected characters in this region. The RAPD analysis manifests a very similar trend of the population grouping. The combined analysis of morphological and molecular data gives the most explicit results. Central European yellow flowering populations ofM. sylvaticum group form two distinctive groups. The first one is an exclusive type of the Alps and of the Hercynian Mountains (except the Sudeten). The second group has its centre of distribution in the eastern part of the Carpathians. This type was described asMelampyrum herbichii from the present Ukrainian Carpathians and was regarded to be endemic to the Eastern and Southern Carpathians. Populations from the Western Carpathians and Sudeten Mts. are polymorphic. They seem to be closer toM. herbichii based on the RAPD markers, whereas the morphology of most populations from these regions is closer toM. sylvaticum s.str. The bract shape seems to be important for discrimination between both groups of populations along with the flower characters and a modest ecological differentiation. The Eastern CarpathianMelampyrum saxosum with white corolla is very close toM. herbichii based on the studied morphological characters.  相似文献   

2.
分析了中国分布单叶蔓荆的种内变异.每个居群随机采取5个以上的完整植株,以16个居群单叶蔓荆作为分类运算单位(operational taxonomic unti,OTU),选取11个有变异的形态学性状和3个品质性状.形态性状以各植株的平均值作为OTUs的原始数据,形成16×14的原始数据矩阵,对矩阵进行聚类分析.根据Q...  相似文献   

3.
The morphological variations of branches, leaves, flowers, fruits and seeds of Caragana microphylla and their correlations with environmental factors were analyzed based on five natural populations in the Xilingol steppe, Inner Mongolia, China. Nested variation analysis showed that there were significant differences in all of the 28 morphological characters within and among populations in 16 morphological characters, and the variations within populations were much greater than those among populations in most morphological characters. Cluster analysis showed that the five populations of C. microphylla could be divided into two groups in morphological characters, and there was significant positive correlation between the divergence of morphological characters matrix and geographical distance matrix. Principal component analysis showed that leaflet length, area of a compound leaf, fresh-mass of a compound leaf, and shoot fresh-mass were main morphological characters that varied among C. microphylla populations. Spearman correlation analysis showed that there were significant correlations between some morphological characters and soil factors. Soil N:P ratio, available N content, total N content, organic matter content and soil water content were main factors that were associated with morphological characters of C. microphylla.  相似文献   

4.
The morphological variations of branches, leaves, flowers, fruits and seeds of Caragana microphylla and their correlations with environmental factors were analyzed based on five natural populations in the Xilingol steppe, Inner Mongolia, China. Nested variation analysis showed that there were significant differences in all of the 28 morphological characters within and among populations in 16 morphological characters, and the variations within populations were much greater than those among populations in most morphological characters. Cluster analysis showed that the five populations of C. microphylla could be divided into two groups in morphological characters, and there was significant positive correlation between the divergence of morphological characters matrix and geographical distance matrix. Principal component analysis showed that leaflet length, area of a compound leaf, fresh-mass of a compound leaf, and shoot fresh-mass were main morphological characters that varied among C. microphylla populations. Spearman correlation analysis showed that there were significant correlations between some morphological characters and soil factors. Soil N:P ratio, available N content, total N content, organic matter content and soil water content were main factors that were associated with morphological characters of C. microphylla.  相似文献   

5.
Abstract The Saussurea nipponica complex was examined with enzyme electrophoresis. Earlier morphological evidence suggested that the complex comprises S. sugimurai and seven subspecies of S. nipponica . Electrophoretic evidence supports the separation of the two species and the subspecies classification of S. nipponica . Nei's genetic distance ( D = 0.19) between S. sugimurai and S. nipponica exceeds the estimated infraspecific level. Saussurea nipponica is newly defined as a species composed of seven infraspecific taxa which have their own distribution ranges and habitats. They are in a very early stage of differentiation. The extensive morphological diversity in S. nipponica is presumed to be a result of geographical isolation under strong environmental selection.  相似文献   

6.
Panzerina lanata ( L. ) Sojak complex is distributed on the Mongolia plateau. Twenty-two populations representing six species in the complex: P. lanata, P. alaschanica, P . kansuensis , P . albescens , P. argyracea and P . parviflora , were sampled throughout the range of the complex including 2 provinces and 3 autonomous regions. Extensive studies were carried out by comparison of wild collection and cultivation, and morphological analysis based on character evaluation and multivariate procedures. It is showed that there exists considerable phenotypic plasticity in some morphological characters, especially those of the root, caudex and leaf. However, the characters of flowers, capsules and seeds were less influenced by environments. The character analysis indicates that some characters, which were used to distinguish taxa of the complex, for example the degree of leaf division, the morphology of calyx and so on, are continuous in a wide range in wild populations. Some “species” in the complex described according to the differences in those characters are only extreme individuals within their continuous variation. As a result, the above analysis and their geographical distribution suggest that P. alaschanica , P. kansuensis , P. albescens be actually the extreme individuals within P. lanata. In the same way, P. argyracea is invalid. The principal components analysis of 11 morphological characters on the individuals from 22 populations shows no differences. Thus, this paper considers that characters such as nutlet with or without wart, size of corolla exceeding calyx or not and dry flowers with or without colour, may be used to distinguish taxa of this complex. From the above analysis, it is indicated finally that the six species in this complex are better reduced taxonomically into two species, namely P. lanata (L.) Sojak and P. parviflora (C. Y. Wu et H. W. Li) Y. Z. Zhao, the difference of two species as follow: Nutlet surface smooth; corolla, 2~2.2 cm long; flower white and unchanging after dry .......................................................... Panzerina parviflora Nutlet surface tuberculate; corolla, 2.5~ 4 cm long; flower white, but becoming yel- lowish after dry ....................................................... P. lanata  相似文献   

7.
Geographical variation and differentiation of flightless leaf beetles of the Chrysolina angusticollis species complex were analysed. Nine morphological groups were recognized on the basis of metric characters relating to body size, shape of hind wing and shape of male genitalia, and binary characters relating to females' elytral surface and larval pubescence. The nine groups were essentially parapatric or allopatric to each other. Five groups occupied a continuous geographical range each, whereas another four groups were disjunctively distributed. Morphometric distance and geographical distance between populations were significantly correlated. Analyses based on 13 allozyme loci demonstrated that six out of the nine morphological groups were further divided into more than one genetically distinct group each. Genetic similarity between populations was significantly correlated with morphometric similarity and geographical closeness. Disjunctively distributed populations of a single morphological group more often resembled geographically adjacent populations of different morphological groups than geographically remote populations of the same group. In a morphological group that occupied a wide continuous range, remote populations substantially differed genetically from each other. The results suggest that there exist at least 19 morphologically and/or genetically differentiated units in the C. angusticollis complex in northern Japan. The C. angusticollis complex is likely a superspecies composed of a number of semispecies. We postulate that the diversification of this species complex might have resulted from the repeated range contraction and expansion during the ice ages. Movement of tension zones that separate two adjacent forms might contribute to enhance their geographical differentiation.  © 2008 The Linnean Society of London, Biological Journal of the Linnean Society , 2008, 93 , 557–578.  相似文献   

8.
依据姜黄属(Curcuma)花卉育种目标,对16份姜黄属植物的11个数量性状及7个质量性状进行因子和聚类分析评价。结果表明,姜黄属植物表型性状复杂多变,供试材料数量性状变异系数介于26.70%~95.44%,叶片主脉绿色,上苞片藕粉或玫红色,晕斑绿色,唇瓣紫色和旗瓣白色为姜黄属典型表型性状。主成分分析表明,9个重要观赏性状归于3个主成分中。根据表型性状各主成分进行聚类分析,供试16份种质被分为三大类群,第Ⅰ类群11个品种均为姜荷花(Curcuma alismatifolia),其中‘清迈粉’的上苞片面积最大,观赏性最突出,但株型偏小。第Ⅱ类群4个品种,花型花色极具特色,株型更大,抗性强,以所罗门姜黄(C. soloensis)表现最优。第Ⅲ类群的女皇郁金(C. petiolata)生长势最为强健。在三个类群之间开展杂交育种有望获得兼具观赏性和生长势的后代。  相似文献   

9.
The morphological differentiation and taxonomic treatment of lowland and high-mountain morphotypes within the Solidago virgaurea group are controversial. To clarify the taxonomic status of these taxa, we conducted a morphometric analysis of 1,746 individuals from 80 localities along an altitudinal gradient from the lowlands of northern Poland to the Carpathians and Sudetes of southern Poland. Multivariate morphometric analyses, cluster analyses and principal component analyses, were used to examine the morphological differentiation within the S. virgaurea group in Poland. Canonical discriminant analysis was applied to determine the morphological characters that best discriminate among the taxa. The stability of the high-mountain Solidago minuta morphotype was tested in an experimental field established in lowland Poland; individuals transplanted from various mountain sites were cultivated at this site, and the morphotypes remained stable in terms of their floral and vegetative characters. Multivariate analyses revealed two morphologically distinct taxa in the S. virgaurea group, which correspond to lowland S. virgaurea s. str. and high-mountain S. minuta as recognised in some European floras. The most important morphological characters for distinguishing the taxa are the number of tubular florets per capitulum, inner involucral bract width and involucre height. Vegetative and inflorescence characters appear to have less taxonomic value because they changed continuously with altitude. A key for identifying S. virgaurea and S. minuta in Poland is presented.  相似文献   

10.
濒危植物缙云卫矛果实、种子形态分化研究   总被引:9,自引:0,他引:9  
对缙云卫矛7个天然种群的果实、种子形态进行研究,测量果实和种子的数量、长度、宽度、重量等22项形态学指标。结果显示:果实、种子的形态性状在种群内和种群间均存在一定程度的变异,种群间变异系数平均值从0.750(种子数/序)到0.062(种子整体形态,长/宽),相比之下种子整体形态最为稳定。在种群水平上,果实、种子的形态性状有一定程度的分化,但不与种群间的地理距离远近相关联。形态分化与环境因子的灰色关联度分析表明,在所研究的环境因子中,没有发现一单一因子对其形态分化起绝对主导作用,不同环境因子对同一性状所起作用不同,且同一环境因子对不同性状的影响效应也有差异。潜在的主导因子是土壤中的全钾含量、土壤厚度以及土壤pH。  相似文献   

11.
A fossil with Gnetum affinity was found in the Jianshangou Member (Barremian Age) of the Yixian Formation (Lower Cretaceous Epoch) of the Jehol Group in western Liaoning, northeastern China. The single fossil specimen is represented by both elongate-cylindrical male spike strobiles which borne within a nodal bract of cauliflorous branch. The spike strobiles have apparent nodes, invisible internodes, and numerous verticillate involucral collars. The microsporangiate units within involucral collars are not seen. The male spike strobiles with verticillate involucral collars occur exclusively in Gnetum; hence, the fossil strobiles are attributed to a new taxon, Khitania columnispicata gen. & sp. nov., being closely related to Gnetum. The general isotopic dating suggests an age of Barremian, ca. 125-122 million years (Myr) ago for the Jianshangou Member. The palaeoecological and palaeoclimatic inference based on the compositions of flora and fauna, and lithological characters of the fossil locality suggests that the fossil plants grew in a subtropical mesophytic forest and under a warmer climate. The remains of male spike strobiles are the first record of gnetalean macrofossil. It documents the evolution of the distinct gnetoid morphology and indicates a wider range of distribution of Gnetaceae in the Early Cretaceous than present day.  相似文献   

12.
BACKGROUND AND AIMS: The aims of this investigation were to highlight the qualitative and quantitative diversity apparent between nine diploid Fragaria species and produce interspecific populations segregating for a large number of morphological characters suitable for quantitative trait loci analysis. METHODS: A qualitative comparison of eight described diploid Fragaria species was performed and measurements were taken of 23 morphological traits from 19 accessions including eight described species and one previously undescribed species. A principal components analysis was performed on 14 mathematically unrelated traits from these accessions, which partitioned the species accessions into distinct morphological groups. Interspecific crosses were performed with accessions of species that displayed significant quantitative divergence and, from these, populations that should segregate for a range of quantitative traits were raised. KEY RESULTS: Significant differences between species were observed for all 23 morphological traits quantified and three distinct groups of species accessions were observed after the principal components analysis. Interspecific crosses were performed between these groups, and F2 and backcross populations were raised that should segregate for a range of morphological characters. In addition, the study highlighted a number of distinctive morphological characters in many of the species studied. CONCLUSIONS: Diploid Fragaria species are morphologically diverse, yet remain highly interfertile, making the group an ideal model for the study of the genetic basis of phenotypic differences between species through map-based investigation using quantitative trait loci. The segregating interspecific populations raised will be ideal for such investigations and could also provide insights into the nature and extent of genome evolution within this group.  相似文献   

13.
Different criteria have been suggested for decisions on character state recognition for morphological characters showing continuous variation from taxon to taxon. A method proposed byMishler andDe Luna seeks to recognize as many character states as the groups of taxon means that are revealed by an analysis of variance (ANOVA) followed by multiple range tests. We apply this method as a guide in decisions of selecting taxonomic characters in species of theBletia reflexa complex. Seven species of the complex, represented by 156 individuals belonging to 54 populations, were the terminal taxa of the study. Character state codes were assigned to 20 characters. These characters together with 12 non-quantitative characters were incorporated into cladistic analyses. Results indicate that the complex is monophyletic only under one outgroup combination.  相似文献   

14.
云南薏苡种质资源农艺性状的主成分和聚类分析   总被引:5,自引:0,他引:5  
为了揭示云南薏苡种质资源多样性,发掘薏苡资源中的有益基因,利用主成分分析和聚类分析,对收集的65个薏苡种质资源的13个农艺性状进行多样性评价。结果表明,云南薏苡资源存在丰富的遗传多样性,其中栽培种的分枝数和分蘖数的遗传变异系数分别达到57.4%和47.5%,野生种百粒重的遗传变异系数达到60.4%。应用主成分分析将云南薏苡13个性状简化为7个主成分,其累积贡献率为85.67%,以叶片宽因子贡献率最高,为49%。采用系统聚类分析,将65份供试材料在遗传距离16.21水平上聚为5个大类,可区分为株高较矮叶片较短型、株高较高叶片较长型以及3个特殊型。  相似文献   

15.
In this study 40 specimens from 8 representative Iranian populations of Onobrychis viciifolia SCOP. were collected from their natural habitats. The specimens were biometrically assessed using 43 quantitative and 15 qualitative morphological characters. At each sample site we recorded ecogeographical variables. In order to evaluate the difference between the variation due to phenotypic responses and genetic adaptation, we generated nucleotide sequence data from the internal transcribed spacer of the nuclear rDNA genes (ITS) and carried out genomic fingerprints using inter‐simple sequence repeat PCR (ISSR). Cluster analysis of morphological characters divided the eight populations into three major groups. Leaf length, leaflet length and width, calyx length, plant height, and stem length were introduced as diagnostic characters for three different morphological groups. Furthermore, canonical correspondence analysis (CCA) of ecogeographical data showed correlations between morphological variations and ecogeographical factors. Clay%, saturation percentage (SP), total neutralizing value (TNV%), texture, minimum temperature, and geographic separation were the main environmental variables associated with morphological groups of O. viciifolia. ISSR analysis revealed three main groups which are in correspondence with morphological groups, indicating that the three morphological groups have been shaped by genetic and phenotypic responses to environmental conditions. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

16.
17.
In a joint analysis of nuclear (allozyme) and mitochondrial markers (sequence and restriction fragment length polymorphism (RFLP) analysis of the 12S and 16S genes), five genetically distinct groups of the Austropotamobius pallipes Lereboullet species complex were detected in the Alpine region. The geographical distribution of these evolutionary lineages coincided largely with several taxa (A.p. pallipes, A. berndhauseri, A.(p.) italicus) formerly defined on the basis of morphological characters. A low level of genetic variability was found within these lineages. For some populations, the combination of the two markers gave additional information about the likelihood of their natural or artificial origin. A hybrid zone was detected between A.p. pallipes and A. berndhauseri in the Lake Geneva area. The mosaic distribution of the five evolutionary lineages indicated that conservation efforts should be aimed at the level of local populations.  相似文献   

18.
Morphological and life-history variation within and between 23 European populations of the introduced and widespread perennial Solidago canadensis L. sensu lato (Asteraceae) was investigated. The populations differed significantly in all 19 characters measured. Coefficients of variation and intraclass-correlations were high for characters related to growth. Floral characters (involucral height, number of disk florets, number of ray florets), and pubescence of stems and leaves varied considerably among sampled shoots, but their frequency distributions were unimodal and the coefficients of variation low. The first three principal components explained 48% of the variation and formed no dusters among the shoots. Several character means correlated with latitude, indicating clinal variation among the populations. Comparison of variation in floral and leaf characters with data from the native range suggests that S. canadensis s.l. naturalized in Europe belongs to a taxon that is close to S. canadensis var. scabra (Muhl.) Torr. & Gray ( S. altissima L.), despite the reported diploid chromosome number of this taxon in Europe.  相似文献   

19.
高山红景天形态分化与生存环境关系的研究   总被引:3,自引:1,他引:2  
对采自黑龙江省平顶山和吉林省长白山的14 个天然居群高山红景天的分株数、株高、基径、叶长和叶宽5 个形态性状进行了比较分析, 探讨了高山红景天适应环境的形态变异机制。单因素方差分析F 检验表明, 除分株数外的4 个形态性状在14 个居群中均表现为差异极显著。对这4 个性状的多重比较分析表明, 各形态性状在不同生态环境下表现出一定程度的分化。对14个天然居群形态性状的聚类分析表明, 高山红景天的形态变异与其生态环境间存在着明显的相关关系。  相似文献   

20.
A total of 235 accessions of Tripsacum dactyloides (L.) L. representing natural populations from 88 locations distributed throughout ten states of the United States were collected in the wild and studied morphologically and cytologically. Multivariate analysis of variance (MANOVA) was applied to 17 morphological characters recorded for 868 specimens from the 88 locations, which were further combined into 25 groups to facilitate analysis. Multivariate F ratios for six comparisons involving different groups were highly significant, indicating that the populations were significantly different on the basis of all 17 characters. Non-significant MANOVA F ratios for two comparisons between sympatric diploid and polyploid accessions showed them to be morphologically similar. Discriminant function (DF) analysis was employed to determine which characters contributed towards group discrimination. No one variable was found to distinguish between groups; rather, a combination of characters was necessary, and the combination changed with each comparison. Accessions were mainly either diploid (2n = 36) or tetraploid (2n = 72), with two triploids (2n = 54) reported from separate locations in Texas. Cytological data revealed that diploids and tetraploids occupy a more sympatric distribution than previously supposed. Morphological analysis suggested that diploids could not always be distinguished from polyploids on the basis of morphology alone, unless the appropriate characters were used. Information from cytological and morphological data showed Tripsacum dactyloides to be composed of many populations covering a wide range of variability, with each population possessing a characteristic combination of morphological attributes. It was concluded that T. dactyloides can be most meaningfully analyzed in terms of particular geographic regions, rather than attempting to elucidate natural relationships by correlating data from the entire United States.  相似文献   

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