Cryptic molecular diversity in the morphologically variable rotiferan Brachionus quadridentatus (Rotifera: Monogononta)

Brachionus quadridentatus is a morphologically variable species distributed worldwide. Its taxonomy is confusing due the numerous infrasubspecific variants described in the taxon. Here we explore genetic diversity of certain B. quadridentatus populations, using sequences of COI mtDNA and 18S rDNA genes. With traditional morphology (taxonomic keys), the specimens identified fell into three recognized variants: B. quadridentatus quadridentatus, B. quadridentatus f. brevispinus and B. quadridentatus f. cluniorbicularis. The coalescent species delimitation analysis highly supports the presence of at least three putative species within B. quadridentatus complex in agreement with the phylogenetic result and GMYC analysis with the 18S gene. Nevertheless, the morphological and mitochondrial information show that the variation within each of the three putative species is much more extensive, finding seven monophyletic and highly divergent genetic groups (>10%) that have congruence with the morphotypes found in this study and ABGD analysis, which display clear morphological differences mainly in the diagnostic characters.

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KoT: an automatic implementation of the K/θ method for species delimitation

10.1101/2021.08.17.454531 ◽

2021 ◽

Author(s):

Yann Spöri ◽

Fabio Stoch ◽

Simon Dellicour ◽

C. William Birky ◽

Jean-François Flot

Keyword(s):

Genetic Diversity ◽

Species Delimitation ◽

Population Genetic ◽

Average Distance ◽

Species Level ◽

Species Boundaries ◽

Fasta File ◽

Genetic Theory ◽

Putative Species ◽

The Impact

K/θ is a method to delineate species that rests on the calculation of the ratio between the average distance K separating two putative species-level clades and the genetic diversity θ of these clades. Although this method is explicitly rooted in population genetic theory, it was never benchmarked due to the absence of a program allowing automated analyses. For the same reason, its application by hand was limited to small datasets of a few tens of sequences. We present an automatic implementation of the K/θ method, dubbed KoT (short for "K over Theta"), that takes as input a FASTA file, builds a neighbour-joining tree, and returns putative species boundaries based on a user-specified K/θ threshold. This automatic implementation avoids errors and makes it possible to apply the method to datasets comprising many sequences, as well as to test easily the impact of choosing different K/θ threshold ratios. KoT is implemented in Haxe, with a javascript webserver interface freely available at https://eeg-ebe.github.io/KoT/ .

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Genetic diversity and population structure in a collection of roselle (Hibiscus sabdariffaL.) from Niger

Plant Genetic Resources ◽

10.1017/s1479262113000531 ◽

2013 ◽

Vol 12 (2) ◽

pp. 207-214 ◽

Cited By ~ 1

Author(s):

Y. Bakasso ◽

M. Zaman-Allah ◽

C. Mariac ◽

C. Billot ◽

Y. Vigouroux ◽

...

Keyword(s):

Genetic Diversity ◽

Population Structure ◽

Fragment Length Polymorphism ◽

Genetic Groups ◽

Diversity Assessment ◽

Farmer Management ◽

Morphological Differences ◽

Close Relatives ◽

The Impact ◽

100 Seed Weight

Roselle (Hibiscus sabdariffaL.) is an economically important plant in Niger. Little is known about its genetic diversity and population structure. In this study, we performed the first diversity assessment of a collection of 124 roselle accessions and 16 accessions of its close relativesHibiscuscannabinusandAbelmoschusesculentus. Our study was based on ten agromorphological traits and 267 amplified fragment length polymorphism markers. We identified two major distinct groups inH. sabdariffausing a Bayesian method. These two genetic groups were associated with statistical differences for three phenological characteristics: number of days to flowering, 100-seed weight and calyx size. However, the calyx colour, i.e. a morphological characteristic often used to classify different local ecotypes, did not superimpose this separation. Our findings suggested that roselle diversity is genetically structured; the two different groups were clearly associated with morphological differences but were not commonly used by farmers for their classification. The impact of the perceived ecotype structure and its consequence on farmer management is discussed.

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Genetic Diversity of Rice stripe necrosis virus and New Insights into Evolution of the Genus Benyvirus

Viruses ◽

10.3390/v13050737 ◽

2021 ◽

Vol 13 (5) ◽

pp. 737

Author(s):

Issiaka Bagayoko ◽

Marcos Giovanni Celli ◽

Gustavo Romay ◽

Nils Poulicard ◽

Agnès Pinel-Galzi ◽

...

Keyword(s):

Genetic Diversity ◽

Genetic Variability ◽

Sierra Leone ◽

Evolutionary History ◽

Molecular Diversity ◽

Genomic Data ◽

Gene Recombination ◽

Necrosis Virus ◽

History Of ◽

Complex Evolutionary History

The rice stripe necrosis virus (RSNV) has been reported to infect rice in several countries in Africa and South America, but limited genomic data are currently publicly available. Here, eleven RSNV genomes were entirely sequenced, including the first corpus of RSNV genomes of African isolates. The genetic variability was differently distributed along the two genomic segments. The segment RNA1, within which clusters of polymorphisms were identified, showed a higher nucleotidic variability than did the beet necrotic yellow vein virus (BNYVV) RNA1 segment. The diversity patterns of both viruses were similar in the RNA2 segment, except for an in-frame insertion of 243 nucleotides located in the RSNV tgbp1 gene. Recombination events were detected into RNA1 and RNA2 segments, in particular in the two most divergent RSNV isolates from Colombia and Sierra Leone. In contrast to BNYVV, the RSNV molecular diversity had a geographical structure with two main RSNV lineages distributed in America and in Africa. Our data on the genetic diversity of RSNV revealed unexpected differences with BNYVV suggesting a complex evolutionary history of the genus Benyvirus.

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Morphology and phylogeny of Halamphora yongxingensis sp. nov. (Bacillariophyta), a new marine benthic diatom isolated from Yongxing Island, South China Sea

Phytotaxa ◽

10.11646/phytotaxa.195.1.3 ◽

2015 ◽

Vol 195 (1) ◽

pp. 53 ◽

Cited By ~ 2

Author(s):

Hai-ying Jiang ◽

Chao-qun Hu ◽

Hai-peng Yang ◽

Lv-ping Zhang ◽

Peng-fei Peng ◽

...

Keyword(s):

Electron Microscopy ◽

South China Sea ◽

South China ◽

18S Rdna ◽

Phylogenetic Analyses ◽

Light And Electron Microscopy ◽

Benthic Diatom ◽

Rbcl Gene ◽

China Sea ◽

Morphological Differences

Halamphora yongxingensis sp. nov., a marine benthic diatom isolated from an intertidal reef around the Yongxing Island, South China Sea (16° 58’ 43.3” N, 112° 14’ 41.7” E), is described in this study on the basis of light and electron microscopy. This diatom is also compared with related taxa such as Halamphora subturgida (Hustedt) Levkov and Amphora subtropica Wachnicka & Gaiser. In addition, phylogenetic analyses based on 18S rDNA and rbcL gene were also conducted. The results revealed that H. yongxingensis was clustered into the Halamphora clade, closely related to Halamphora montana (Krasske) Levkov. We discuss morphological differences between H. yongxingensis and H. montana.

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Species delimitation and population structure in three Onosma (Boraginaceae) species

Biologia ◽

10.1515/biolog-2015-0151 ◽

2015 ◽

Vol 70 (10) ◽

Author(s):

Masoud Sheidai ◽

Samira Sadeghi ◽

Mahnaz-Arab Ameri ◽

Ahmad-Reza Mehrabeian

Keyword(s):

Genetic Diversity ◽

Population Structure ◽

Species Delimitation ◽

Genetic Difference ◽

Morphological Variability ◽

Morphological Diversity ◽

Mantel Test ◽

Geographical Distance ◽

Nj Tree ◽

Issr Molecular Markers

AbstractThe present study aimed to reveal genetic diversity and population structure in three Onosma species i.e., Onosma bulbotrichum DC., O. elwendicum Wettst. and O. sericeum Willd. (Boraginaceae) growing in Iran. This study was performed to check if the ISSR molecular markers could be used in the Onosma species delimitation. We also investigated the infra-specific morphological variability and if we can identify infra-species taxonomic forms. The present study revealed within species genetic and morphological diversity. ISSR data could delimit the studied species as they were separated from each other in NJ tree, maximum parsimony and STRUCTURE analysis. AMOVA and Hickory tests produced significant genetic difference among the studied species. The Mantel test showed no correlation between genetic distance and geographical distance of the populations for all three species. Reticulation analysis and Nm estimation showed gene flow among these populations. We could identify a few ISSR loci that are adaptive. Data obtained can be used in conservation of these medicinal plants in Iran.

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Genetic diversity and phylogenetic behavior of some minor legumes

International Journal of Plant Biology ◽

10.4081/pb.2016.6136 ◽

2016 ◽

Vol 7 (1) ◽

Author(s):

James Oludare Agbolade ◽

Ronke Justina Komolafe

Keyword(s):

Genetic Diversity ◽

Principal Component ◽

Calyx Lobe ◽

Descriptive Statistics ◽

International Institute ◽

Mean Values ◽

Phylogenetic Relatedness ◽

Petal Length ◽

Morphological Differences ◽

Range Test

Twenty-four accessions of twelve species minor legumes collected from the germplasm unit of the International Institute of Tropical Agriculture Ibadan, Nigeria were evaluated for their genetic diversities and phylogenetic relatedness. The accessions were planted into plots of 5 ridges of 5 meters long, spaced 1 meter apart and replicated three times at the Federal University Oye-Ekiti Teaching and Research Farm. The diversity and the relative phylogeny of the accessions were assessed through their floral morphological differences and the mean values between two accessions were evaluated by descriptive statistics. Principal component analysis was employed to identify the most discriminatory floral morphological traits and the similarities among the 24 accessions were assessed by cluster analysis (CA). Descriptive statistics through Duncan multiple range test adopted revealed genetic diversity and phylogenetic relatedness among the accessions. The first two principal component axes explained 64.66% of the total floral morphological variation. Standard petal length, calyx lobe length and stipule length contributed most of the variations in the legume accession. CA grouped the 24 accessions into six clusters. The study revealed intra-specific similarities and inter-specific floral morphological differences among the studied accessions.

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SSR DNA marker aided genetic diversity assessment of selected willow clones

Genetika ◽

10.2298/gensr1302527s ◽

2013 ◽

Vol 45 (2) ◽

pp. 527-536 ◽

Cited By ~ 3

Author(s):

N.B. Singh ◽

S. Joshi ◽

P. Choudhary ◽

J.P. Sharma

Keyword(s):

Genetic Diversity ◽

Molecular Diversity ◽

Dna Marker ◽

Similarity Coefficient ◽

Gene Pools ◽

Morphometric Traits ◽

Genetic Base ◽

Diversity Assessment ◽

Ssr Primers ◽

Clustering Pattern

Around 100 clones of tree willows were subjected for nursery screening twice on morphometric traits. Genetic diversity was assessed in twenty-five genetically superior willow clones hailing from six countries using 16 SSR primers. Fourteen primers amplified the DNA but only ten showed polymorphism. Total 34 bands were scored, out of that 27 were found to be polymorphic and 7 were monomorphic. Three primers showed 100% polymorphism whereas 79.4% polymorphism was recorded in total. The dendrogram obtained from SSR markers revealed that clone SE-69-002 (S. matsudana) and NZ-1040 (S. matsudana X S. alba) as most similar clones (Jaccards coefficient of 0.97), and clone PN-721(S. matsudana X S. alba) and PN-731 (S. nigra), as most divergent clones (Jaccards coefficient of 0.63). All the genotypes were grouped into 4 distinct clusters. On the basis of similarity coefficient analysis the first cluster comprised of 11 genotypes, the second cluster have 8 genotypes where as third one has only one genotype and fourth cluster retained five genotypes. The clustering pattern further indicated that the geographic distribution may not be the reflection of genetic diversity in willow clones. Genotypes with high molecular diversity could be used in breeding programme in order to obtain heterotic hybrids and development of gene pools with broad genetic base. The genotype specific bands developed by the SSR primers could also be used for identification of cultivar.

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Morphological and genetic diversity of traditional varieties of agave in Hidalgo State, Mexico

10.21203/rs.3.rs-143808/v1 ◽

2021 ◽

Author(s):

Carmen Julia Figueredo-Urbina ◽

Gonzalo D. Álvarez-Ríos ◽

Mario Adolfo García-Montes ◽

Pablo Octavio-Aguilar

Keyword(s):

Genetic Diversity ◽

Morphological Characteristics ◽

Plant Size ◽

Structured Interviews ◽

Main Method ◽

Domestication Syndrome ◽

Cultural Importance ◽

Genetic Groups ◽

Expected Heterozygosity ◽

Distilled Beverages

Abstract Background: The agaves are plants of cultural importance that have been used by humans for about 10,000 years for about 40 specific uses, of which the most culturally and economically important are fermented (Pulque) and distilled beverages (Mescal). Pulque continues to be produced in nearly all of Mexico, and the agaves used for this propose have shown domestication syndrome and selected morphological characteristics, such as larger plant size (since size is positively related to sap production) and less dentition of the leaves.Methods: In this study, we carry out an ethnobotanical, morphological and genetic analysis of the traditional varieties of pulque agave used in the production of aguamiel (agave sap) and pulque in two localities of the state of Hidalgo. We did semi-structured interviews and tours with crop owners, tlachiqueros (sap harvesters), and people related to the production system. We analyzed the morphology of 111 plants, and we studied the diversity and genetic structure of 130 individuals using 16 nuclear microsatellites.Results: We found wild, tolerated, transplanted, and cultivated varieties of agave. Asexual reproduction was the main method of propagation. We recorded 19 traditional varieties of pulque agave, 12 of them in production during the study, which correspond to the species Agave americana, A. salmiana y A. mapisaga with five intraspecific entities. The varieties were grouped according to a management gradient; the wild varieties were the smallest, with more lateral teeth and a larger terminal spine. The cultivated varieties clearly exhibited domestication syndrome, with larger plants and smaller dentition. The expected heterozygosity (He) of the varieties ranged between 0.204 to 0.721. Bayesian clustering suggested the existence of three genetic groups (K = 3), both at the level of traditional varieties of pulque agaves and for management categories, a result that matches multivariate clustering.Conclusions: Pulque producers in the studied localities, maintain high agrobiodiversity. The cultivated varieties exhibit domestication syndrome, as has been reported for other species of the genus with the same selection purposes. Our results support the hypothesis of a decrease in genetic diversity in crops compared to wild agaves, which seems to be due to vegetative propagation, among other factors.

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Assessment of genetic diversity in Indian Barnyard millet (Echinochloa spp. complex) using morphological and molecular markers

Journal of Applied and Natural Science ◽

10.31018/jans.v8i3.1016 ◽

2016 ◽

Vol 8 (3) ◽

pp. 1643-1648 ◽

Cited By ~ 1

Author(s):

M. P. Moharil ◽

Dipti Gawai ◽

N. Dikshit ◽

M.S. Dudhare ◽

P. V. Jadhav

Keyword(s):

Genetic Diversity ◽

Molecular Markers ◽

Genetic Improvement ◽

Molecular Diversity ◽

Genetic Relationships ◽

Barnyard Millet ◽

Clear Cut ◽

Cultivated Species ◽

High Degree

In the present study, morphological and molecular markers (RAPD primers) were used to analyze the genetic diversity and genetic relationships among 21 accessions of Echinochloa spp. complex comprising the wild and cultivated species collected from Melghat and adjoining regions of Vidarbha, Maharashtra. The availability of diverse genetic resources is a prerequisite for genetic improvement of any crop including barnyard millet. A high degree of molecular diversity among the landraces was detected. Among the 21 genotypes, two major groups (A and B) were formed, at 67.28 % similarity, which clearly encompasses 15 accessions of E. frumentacea and 6 accessions of E. colona. Higher similarity was observed in accessions of E. frumentacea. The accessions IC 597322 and IC 597323 also IC 597302 and IC 597304 showed more than 94% similarity among themselves. The classification of genetic diversity has enabled clear-cut grouping of barnyard millet accessions into two morphological races (E. frumentacea and E. colona).

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Molecular Diversity Analysis in Boro Rice (Oryza sativa L.) Landraces using SSR Markers

Asian Journal of Biology ◽

10.9734/ajob/2021/v12i130156 ◽

2021 ◽

pp. 36-48

Author(s):

Farhana Afrin Vabna ◽

Mohammad Zahidul Islam ◽

Md. Ferdous Rezwan Khan Prince ◽

Md. Ekramul Hoque

Keyword(s):

Genetic Diversity ◽

Ssr Markers ◽

Molecular Diversity ◽

Genetic Relationships ◽

Group Method ◽

Diversity Analysis ◽

Average Value ◽

Rice Landraces ◽

Boro Rice ◽

Research Institute

Aims: The aim of the study was to determine the genetic diversity of twenty four Boro rice landraces using rice genome specific twelve well known SSR markers. Study Design: Genomic DNA extraction, PCR amplification, Polyacrylamide gel electrophoresis (PAGE) and data analysis-these steps were followed to perform the research work. Data was analysed with the help of following software; POWERMAKER version 3.25, AlphaEaseFC (Alpha Innotech Corporation) version 4.0. UPGMA dendrogram was constructed using MEGA 5.1 software. Place and Duration of Study: The study was conducted at the Genetic Resources and Seed Division (GRSD), Bangladesh Rice Research Institute (BRRI), Joydebpur, Gazipur, Bangladesh during the period of November 2017 to March 2018. Methodology: Simple Sequence Repeat (SSR) markers were used to assay 24 landraces of Boro rice collected from the Gene Bank of Bangladesh Rice Research Institute (BRRI). Results: A total fifty four (54) alleles were detected, out of which forty five (45) polymorphic alleles were identified. The Polymorphic Information Content (PIC) of SSR markers ranged from 0.08 (RM447) to 0.84 (RM206) with an average value of PIC = 0.49. Gene diversity ranges from 0.08 (RM447) to 0.86 (RM206) with an average value of 0.52. The RM206 marker can be considered as the best marker among the studied markers for 24 rice landraces. Dendrogram based on Nei’s genetic distance using Unweighted Pair Group Method of Arithmetic Mean (UPGMA) indicated the segregation of 24 genotypes into three main clusters. Conclusion: The result revealed that SSR markers are very effective tools in the study of genetic diversity and genetic relationships and this result can be conveniently used for further molecular diversity analysis of rice genotypes to identify diverse parent for the development of high yielding variety in rice.

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