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

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.

2004 ◽  
Vol 118 (3) ◽  
pp. 326 ◽  
Author(s):  
Caroline Healy ◽  
Lynn J. Gillespie

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.


2015 ◽  
Vol 43 (3) ◽  
pp. 293-299 ◽  
Author(s):  
Y Bakis ◽  
MT Babaç

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)


2006 ◽  
Vol 80 (4) ◽  
pp. 357-361 ◽  
Author(s):  
J.M. de Gruijter ◽  
J. Blotkamp ◽  
R.B. Gasser ◽  
S. Amponsah ◽  
A.M. Polderman

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.


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 ◽  
...  

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.


Scientifica ◽  
2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Agnes Omire ◽  
Nancy L. M. Budambula ◽  
Johnstone Neondo ◽  
Robert Gituru ◽  
Cecilia Mweu

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.


2011 ◽  
Vol 78 (1) ◽  
pp. 51-61 ◽  
Author(s):  
Magdalena Szczepaniak

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.


2015 ◽  
Vol 74 (1) ◽  
pp. 1-17 ◽  
Author(s):  
Zohra Ben Cheikh-Affene ◽  
Faouzi Haouala ◽  
Fethia Harzallah-Skhiri

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.


2018 ◽  
Vol 17 (03) ◽  
pp. 213-220 ◽  
Author(s):  
Teresa Bieńkowska ◽  
Elżbieta Suchowilska ◽  
Wolfgang Kandler ◽  
Rudolf Krska ◽  
Marian Wiwart

AbstractThe grain of modern wheat cultivars has a significantly lower mineral content, including the content of copper, iron, magnesium, manganese, phosphorous, selenium and zinc. For this reason cereal breeders, are constantly searching for new genetic sources of minerals that are essential in human nutrition. Triticum polonicum, which is grown on a small scale in Spain, southern Italy, Algeria, Ethiopia and warm regions of Asia, deserves special attention in this context. The micronutrient and macronutrient content of T. polonicum versus T. durum and T. aestivum was compared in this study. Polish wheat grain was characterized by the significantly highest content of phosphorus (4.55 g/kg), sulphur (1.82 g/kg), magnesium (1.42 g/kg), zinc (49.5 mg/kg), iron (39.1 mg/kg) and boron (0.56 mg/kg) as well as a low content of aluminium (only 1.04 mg/kg). The macronutrient profile of most T. polonicum lines differed completely from that of common wheat and durum wheat. The principal component analysis supported discrimination of seven Polish wheat lines with a particularly beneficial micronutrient profile (P2, P3, P5, P7, P9, P22 and P25). These lines were characterized by the highest content of copper, iron and zinc, as well as the lowest concentrations of strontium, aluminium and barium which are undesirable in food products. The above lines can be potentially applied as source materials for breeding new wheat varieties. The results of this study indicate that Polish wheat could be used in genetic biofortification of durum wheat and common wheat.


1990 ◽  
Vol 1 (3) ◽  
pp. 131-144
Author(s):  
María Coscarón

Cluster analysis by four methods and a principal component analysis were performed using data on 24 morphological characters of 27 species of the genus Rasahus (Peiratinae). The results obtained by the different techniques show general agreement. They confirm the present number of taxa and reveal the existence within the genus of three groups of species: scutellaris , hamatus and vittatus. The scutellaris group is constituted by R. aeneus (Walker), R. maculipennis (Lepelletier and Serville), R. bifurcatas Champion, R. castaneus Coscarón, R. guttatipennis (Stål), R. flavovittarus Stål, R. costarricensis Coscarón, R. scutellaris (Fabricius), R. atratus Coscarón, R. peruensis Coscarón, R. paraguayensis Coscarón, R. surinamensis Coscarón, R. albomaculatus Mayr, R. brasiliensis Coscarón and R. sulcicollis (Serville).The hamatus group contains R. rufiventris (Walker), R. hamatus (Fabricius), R. amapaensis Coscarón, R. arcitenens Stål, R. limai Pinto, R. angulatus coscarón, R. thoracicus Stål, R. biguttatus (Say), R. arcuiger (Stål), R. argentinensis Coscarón and R. grandis Fallou. The vittatus group contains R. vittatus Coscarón. The characters used to separate the groups of species are: shape of the pygophore, shape of the parameres, basal plate complexity, shape of the postocular region and hemelytra pattern. Illustrations of the structures of major diagnostic importance are included.


2019 ◽  
Vol 4 (3) ◽  
pp. 97
Author(s):  
Donan Satria Yudha ◽  
M Zulfiqar Meizar Pratama ◽  
Rury Eprilurahman

There are five species of deer (family Cervidae) living in Indonesia today. Male deer possesses antlers, a unique character of male deer. Antlers have economic values for quite a long time. Antler’s growth is influenced by several factors, therefore each species of deer have its own unique antlers’ shape and size. Antler’s identification usually relies on size measurement and overall shape of complete antlers which still attach to the skull. It is difficult to identify shed, broken or individual antler. The purpose of the research is to understand antlers’ morphological characters on each species to become diagnostic characters. Specimens analysed were collections of LIPI and were analysed with Principal Component Analysis (PCA) using PAST3 software. The results showed each species of deer having their own unique antlers’ character, and so it can be used to determine the species of Indonesian deer. The important structures for identification are relief, pedicle, brow, bez, and main beam.


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