scholarly journals Biosystematic studies of Elymus repens (L.) Gould (Poaceae): patterns of phenotypic variation

2011 ◽  
Vol 78 (1) ◽  
pp. 51-61 ◽  
Author(s):  
Magdalena Szczepaniak
Keyword(s):  
Morphological Variability ◽  
Habitat Type ◽  
Principal Component ◽  
Morphological Characters ◽  
Cool Season ◽  
Multivariate Statistical ◽  
Morphological Gradient ◽  
Taxonomic Descriptions ◽  
Elymus Repens ◽  
Morphological Patterns

Inter- and intrapopulational morphological variability of <em>Elymus repens</em>, a cool-season peren-nial grass and a tenacious weed that spreads both by seeds and rhizomes forming a thick and stout net, was examined. Multivariate statistical analysis of 48 initial morphological characters obtained from 44 population samples (1180 specimens) collected in different habitats revealed the conspicuous variation within <em>E. repens</em>. Principal Component Analysis revealed three extremes of the morphological gradient that were referred to as three varieties of <em>E. repens</em>: var. <em>repens</em>, var. <em>aristatus</em> and var. <em>subulatus</em>, not correlated with the habitat type or geographi-cal location. Canonical Discriminant Analysis proved the taxonomic usefulness of characters such as awned or awnless glumes and lemmas as well as the shape of glumes for variety di-stinction. Results of morphological analysis, in relation to the low level of genetic variation showed in the previous studies, suggest that the extensive morphological variation of <em>E. re-pens</em> can be caused by its plasticity where different morphological patterns are realized on the same genome basis. Additionally, the open-pollinated system of mating results in new combi-nations of morphological characters of plants that further reproduce vegetatively by rhizomes. The nomenclature, taxonomic descriptions and a key to the three varieties are provided.

scholarly journals A Systematic Analysis of the Alpine Saxifrage Complex (Saxifragaceae) in the Canadian Arctic Islands Using Morphology and Chloroplast DNA Data

2004 ◽  
Vol 118 (3) ◽  
pp. 326 ◽  
Author(s):  
Caroline Healy ◽  
Lynn J. Gillespie
Keyword(s):  
Morphological Variability ◽  
Canadian Arctic ◽  
Principal Component ◽  
Distinct Species ◽  
Morphological Characters ◽  
Sympatric Species ◽  
Sensu Stricto ◽  
Morphological Data ◽  
Systematic Analysis ◽  
Site Analysis

The Saxifraga nivalis complex displays significant ecological, morphological and cytological variation. Most European studies suggest that the S. nivalis complex comprises two distinct species: Saxifraga nivalis sensu stricto and Saxifraga tenuis. However, the presence of intermediate morphotypes, inconsistencies in chromosomal counts and variability in morphological keys and descriptions have led to different taxonomic interpretations of the complex in North America. This study investigated the systematics of Canadian Arctic Island members of this complex from 157 specimens using 23 morphological characters. Principal component analysis of the morphological data revealed two adjacent clusters, corresponding to the two taxa and consistent with a close morphological similarity and the presence of hybrids. A preliminary restriction site analysis of five non-coding regions of the chloroplast genome, trnH-trnK, trnT-trnF, trnF-trnV, trnV-rbcL and rbcL-ORF106, was conducted using 21 restriction endonucleases. This analysis indicated a length difference between the trnT-trnF region of S. nivalis and that of S. tenuis, but no difference in restriction sites for any of the assayed regions. These results confirm that in the Canadian Arctic, the S. nivalis complex consists of two closely related, largely sympatric species, with notable morphological variability, and possible hybrids.

scholarly journals Morphological variability of acorns and its taxonomic significance in Quercus. from Turkey

2015 ◽  
Vol 43 (3) ◽  
pp. 293-299 ◽  
Author(s):  
Y Bakis ◽  
MT Babaç
Keyword(s):  
Principal Component Analysis ◽  
Morphological Variability ◽  
Morphological Characteristics ◽  
Principal Component ◽  
Component Analysis ◽  
Morphological Characters ◽  
Taxonomic Significance ◽  
Morphological Variations ◽  
Quercus Species ◽  
Different Populations

Morphological variations of acorn among and within the groups of Quercus species were studied. A total of 617 acorns belonging to 14 species representing all 3 sections of Quercus L. (Fagaceae) in Turkey were examined in this study. Specimens were collected from 47 different populations over both Anatolian and Thrace part of Turkey. Principal component analysis was used to analyze the morphological characteristics of acorns. Results obtained from this study demonstrate the use of morphological characters in differentiating the taxa of Quercus and Cerris sections studied. Another important finding is the introgression among the acorns of species within Quercus section DOI: http://dx.doi.org/10.3329/bjb.v43i3.21601 Bangladesh J. Bot. 43(3): 293-299, 2014 (December)

Morphological variability withinOesophagostomum bifurcumamong different primate species from Ghana

2006 ◽  
Vol 80 (4) ◽  
pp. 357-361 ◽  
Author(s):  
J.M. de Gruijter ◽  
J. Blotkamp ◽  
R.B. Gasser ◽  
S. Amponsah ◽  
A.M. Polderman
Keyword(s):  
Principal Component Analysis ◽  
Morphological Variability ◽  
Principal Component ◽  
Morphological Characters ◽  
Primate Species ◽  
Distinct Population ◽  
Genetic Studies ◽  
Olive Baboons ◽  
Green Monkey ◽  
Length Width

AbstractAdultOesophagostomum bifurcum(Nematoda: Strongylida) from human and non-human primates from Ghana were compared in order to investigate the extent of morphological variability within the species. Using analysis of variance and principal component analysis, significant differences in morphological characters (such as parasite length, width, length of the oesophagus and length of spicules) were demonstrated betweenO. bifurcumworms from humans, the Mona, Patas or Green monkey and/or Olive baboons. These findings suggest thatO. bifurcumfrom different species of primate host represent distinct population variants, also supported by recent epidemiological and genetic studies ofO. bifurcumfrom such hosts.

scholarly journals Morphological variability of recent species of the order Cassiduloida (Echinodermata: Echinoidea) of Mexico

2021 ◽  
Vol 69 (Suppl.1) ◽  
pp. 423-437
Author(s):  
Andrea-Alejandra Caballero-Ochoa ◽  
Blanca-E. Buitrón-Sánchez ◽  
Carlos-A. Conejeros-Vargas ◽  
Brenda-L. Esteban-Vázquez ◽  
Mariana-P. Ruiz-Nava ◽  
...  
Keyword(s):  
Direct Relationship ◽  
Morphological Variability ◽  
Principal Component ◽  
Morphological Characters ◽  
Morphometric Characters ◽  
Living Species ◽  
Qualitative Characters ◽  
Recent Species ◽  
Taxonomic Studies ◽  
Character Correlations

ntroduction: In Mexico, there are two recorded living species of Cassiduloida: Cassidulus caribaearum and Rhyncholampas pacifica. Most of the taxonomic studies on cassiduloids have used external morphology, pedicellariae and morphometric characters; however, the intraspecific variation of quantitative and qualitative characters has been poorly evaluated. Objective: To compare the basic morphology of R. pacifica and C. caribaearum. Methods: We examined a total of 2 158 specimens of R. pacifica and C. caribaearum, selecting 50 to evaluate shape and size with linear regression and Principal Component analysis. We selected an additional 62 specimens per species to identify significant character correlations and morphological groups within species. Results: There is a direct relationship between Test length and Test width. Test height/Test width, and Total length (oral view)/Distance from the ambitus to the peristome apex, are the two main ratios to distinguish both species. C. caribaearum is more dorsoventrally compressed and has a round peristome base; versus R. pacifica has a tall and triangular one. There are four morphological groups of C. caribaearum and two groups for R. pacifica. Conclusions: These two species can be distinguished with reliable morphological characters, in which peristome shape suggests that R. pacifica is more adapted to burrowing deeper into certain types of substratum.

scholarly journals Variations and Phenetic Analysis of Peanut Cultivars (Arachis hypogaea L.) Based on Morphological Characteristics

2019 ◽  
Vol 4 (1) ◽  
pp. 24
Author(s):  
Purnomo Purnomo ◽  
Nurul Khotimah
Keyword(s):  
Arachis Hypogaea ◽  
Similarity Index ◽  
Morphological Characteristics ◽  
Principal Component ◽  
Morphological Characters ◽  
Morphological Properties ◽  
Multivariate Statistical ◽  
Pair Group ◽  
Arachis Hypogaea L ◽  
Peanut Cultivars

Peanut (Arachis hypogaea L.) is a food commodity that is widely cultivated in Indonesia. At present there has been no analysis of the relationship between peanut cultivars with phenetic methods based on the morphological properties of the plants. Four cultivars of Arachis hypogaea L. Tuban, Talam 1, Talam 2, and Talam 3 used in this research. Morphological characters data was analyzed by description to construct identification key. Similarity index was counted by Simple Matching Coefficient (SSm) formula based on morphological scoring. Cluster analysis was conducted by UPGMA (Unweighted Pair Group Methods using Arithmetic Averages) method to construct dendrogram. PCA (Principal Component Analysis) were performed to defined role of each morphological character in grouping of accessions with MVSP (Multivariate Statistical Program) v. 3.1 software.  The dendrogram showed that four cultivars of Arachis hypogaea L. divided into two main clusters, 4 sub-clusters. The similarity index of clusters is 0.85%.

scholarly journals Morphological Variability of Snowdrops in the Central Part of the Balkan Peninsula

HortScience ◽  
2018 ◽  
Vol 53 (8) ◽  
pp. 1119-1124 ◽  
Author(s):  
Filip Jovanović ◽  
Dragica Obratov-Petković ◽  
Ivana Bjedov ◽  
Ivana Živanović ◽  
Sonja Braunović ◽  
...  
Keyword(s):  
Morphological Variability ◽  
Morphological Differentiation ◽  
Balkan Peninsula ◽  
Morphological Characters ◽  
Multivariate Statistical ◽  
Southeastern Part ◽  
Naturally Occurring ◽  
Total Variability ◽  
Galanthus Nivalis ◽  
The Republic

To address the issues of taxonomic delimitation and to select the material with desirable traits for horticultural use, a comprehensive study of the total variability of morphological characters of two naturally occurring snowdrop species (Galanthus nivalis L. and Galanthus elwesii Hook.) in the central part of the Balkan Peninsula was conducted. The analyses were performed for 16 quantitative characters of aboveground parts of 630 plants collected at 21 geographical points in the territory of the Republic of Serbia. To identify the trends in morphological differentiation, descriptive, univariate and multivariate statistical procedures were employed. Most of the examined characters exhibited moderate degrees of variability (cv from 10% to 20%) and the values of several characters exceeded the limits of variation stated in literature. Samples were mostly morphometrically homogeneous, with comparatively high similarity; only four populations of G. nivalis from the southern and southeastern part of the country were discrete. It is questionable whether these populations merit formal taxonomic recognition at any infraspecific level, but given their decorative qualities, the selected plants can be introduced into cultivation as horticultural plants.

scholarly journals Phenotypic Diversity of Doum Palm (Hyphaene compressa), a Semi‐Domesticated Palm in the Arid and Semi‐Arid Regions of Kenya

Scientifica ◽  
2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Agnes Omire ◽  
Nancy L. M. Budambula ◽  
Johnstone Neondo ◽  
Robert Gituru ◽  
Cecilia Mweu
Keyword(s):  
Rural Communities ◽  
Morphological Traits ◽  
Phenotypic Diversity ◽  
Morphological Variability ◽  
Coastal Region ◽  
Principal Component ◽  
Morphological Characters ◽  
Fruit Traits ◽  
Coastal Regions ◽  
Linear Discriminant

Hyphaene compressa is an economically important palm in Africa. Despite its significant role in the livelihoods of rural communities, the diversity of doum palm is poorly documented and studied. In addition, it has no model descriptor that can aid such studies. Ninety H. compressa accessions collected from Northern, Eastern, and Coastal regions of Kenya were examined to determine the morphological variability of the vegetative and fruit traits of H. compressa and to identify its morphotypes for improvement. A total of 19 morphological characters including seven quantitative and 12 qualitative traits of fruit and vegetative traits were selected. Linear mixed-effects models, principal component analysis, and linear discriminant analyses were used to assess the variation in the morphological traits of doum palm based on the regions. Hierarchical clustering was performed to identify the morphotypes of H. compressa. There was variability in H. compressa morphological traits, particularly at the Kenyan Coast. All seven quantitative traits were able to effectively discriminate doum palm phenotypically p ≤ 0.001 . The 90 accessions clustered into five morphotypes designated as 1, 2, 3, 4, and 5. Morphotype 4 was specific only to the Coastal region. Morphotype 5 had the tallest trees with the biggest fruits and included palms from Eastern and Coastal regions making it the best morphotype for fruit traits. This study will inform the domestication, improvement, and conservation of H. compressa by selecting elite accessions.

scholarly journals Assessment of Agro-Morphological Variability in a Durum Wheat Collection Maintained in the Moroccan Gene Bank

2022 ◽  
pp. 31-42
Author(s):  
Youssef Chegdali ◽  
Hassan Ouabbou ◽  
Abdelkhalid Essamadi
Keyword(s):  
Durum Wheat ◽  
Morphological Variability ◽  
Principal Component ◽  
Morphological Characters ◽  
Gene Bank ◽  
Large Variability ◽  
High Productivity ◽  
Crop Genetic Diversity ◽  
Augmented Design ◽  
High Yielding Varieties

Durum wheat is one of the most important cereal crops in Morocco. The development of high-yielding varieties of durum wheat is one of the major goals of breeding programs in Morocco. Crop genetic diversity should play an essential role in this context. The objective of this study was to assess the genetic variation among 280 durum wheat accessions conserved at the Moroccan Gene Bank by using twelve agro-morphological characters. All accessions are planted in field conditions and arranged in augmented design. The results showed a large variability among the durum wheat accessions. Analysis of variance demonstrated significant to highly significant differentiation between the accessions for the most traits. The number of plants at the emergence stage, the biomass of the plant at the flowering stage, the chlorophyll content, and the number of spikes showed high genetic advance coupled with high heritability (broad sense). Moreover, highly significant coefficients of correlation were revealed between agro-morphological characters offering the possibility of direct or indirect selection. The first two axes of the principal component analysis explained 45% of the total variation and showed that Moroccan landraces and North American cultivars shared similar morphological characters. However, Moroccan cultivars have shown better agronomic characters. This important agro-morphological variation should be utilized as a gene pool in durum wheat improvement to develop novel varieties with high productivity and the best quality.

A revision of taxonomic relation between Oenothera royfraseri and O. turoviensis (sect. Oenothera, subsect. Oenothera; Onagraceae) based on multivariate analyses of morphological characters

Phytotaxa ◽  
2020 ◽  
Vol 435 (2) ◽  
pp. 164-180
Author(s):  
MONIKA WOŹNIAK-CHODACKA
Keyword(s):  
Discriminant Analysis ◽  
Quantitative Traits ◽  
Multivariate Analyses ◽  
Principal Component ◽  
Morphological Characters ◽  
Glandular Hair ◽  
Multivariate Statistical Analyses ◽  
Multivariate Statistical ◽  
Qualitative And Quantitative ◽  
Taxonomic Relation

The taxonomic relation between Oenothera royfraseri and O. turoviensis (sect. Oenothera, subsect. Oenothera; Onagraceae) has remained unresolved. According to the representatives of the so-called American school of taxonomy (W. Dietrich, P.H. Raven, W.L. Wagner) the former name is one of almost 70 synonyms of widely treated O. biennis (AB-II plastome-genome combination) while the latter is a synonym of O. parviflora (BC-IV arrangement). On the other hand, European researchers (K. Rostański, A. Soldano, V. Jehlík) tend to assign both names to one species, under the name O. royfraseri. In order to establish the taxonomic relation of the studied taxa, morphometric comparisons, based on qualitative and quantitative traits, were carried out. The studies included European specimens labelled as O. royfraseri and/or O. turoviensis (with the nomenclatural types of the two names) as well as representatives of the two other species, O. biennis and O. parviflora, which were taken as a background. The performed multivariate statistical analyses (correspondence analysis, principal component analysis, discriminant analysis followed by canonical discriminant analysis) provided strong evidence supporting the American’s hypothesis on separateness of the two species. As it was demonstrated, O. royfraseri and O. turoviensis differ mostly by the sepal tips arrangement, which is considered by American and European researchers as one of the most essential variables in taxa recognition within the group. The obtained results have also indicated that O. royfraseri is distinct from European representatives of O. biennis, which is partially concordant with Rostański’s opinion. The two last-mentioned species can be discriminated by red vs. green papillae, strigillose vs. glandular hair predominance, respectively, as well as by quantitative features of the flowers, which are significantly larger in O. biennis.

scholarly journals Morphometric variation and taxonomic identification of thirteen wild rose populations from Tunisia

2015 ◽  
Vol 74 (1) ◽  
pp. 1-17 ◽  
Author(s):  
Zohra Ben Cheikh-Affene ◽  
Faouzi Haouala ◽  
Fethia Harzallah-Skhiri
Keyword(s):  
Phenotypic Diversity ◽  
Morphological Variability ◽  
Principal Component ◽  
Hierarchical Cluster ◽  
Morphological Characters ◽  
Morphological Identification ◽  
Taxonomic Identification ◽  
Morphometric Variation ◽  
Central Tunisia ◽  
Hierarchical Cluster Analyses

AbstractThirteen populations of wild roses (Rosa L.) growing in northern and central Tunisia have been used for studies on the discrimination between accessions and populations. Thirty-eight morphological characters related to the branches, prickles, leaves and corymbs were measured on the collected accessions to study the phenotypic diversity among and within species. Principal component and hierarchical cluster analyses (PCA and HCA) separated rose accessions into two distinctive groups and eight subgroups. A taxonomic interpretation of the morphological variability has shown that Tunisian rose populations belong to two sections (Synstylae and Caninae) of the genus Rosa. Moreover, they have been identified as seven separated taxa: R. sempervirens L., R. sempervirens var. submoshata Rouy., R. sempervirens var. prostrata Lindl. belonging to Synstylae section and R. canina L., R. agrestis Savi., R. micrantha Smith. and R. dumetorum Thuill. belonging to Caninae section. PCA and HCA proved that morphological characters used in taxonomic identification such as styles form, leaf and leaflets length, number of flowers by corymb, leaflet serration, presence of glands in leaflet, peduncle, receptacle and sepal have a high value of discrimination, and have been very successful in morphological identification.

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