A Major Disjunction in Genetic Diversity Over the Geographic Range of Acacia melanoxylon R.Br

1993 ◽  
Vol 41 (3) ◽  
pp. 355 ◽  
Author(s):  
J Playford ◽  
JC Bell ◽  
GF Moran
Keyword(s):  
Genetic Diversity ◽  
Genetic Variability ◽  
Genetic Distance ◽  
Allozyme Variation ◽  
Geographic Range ◽  
Considerable Time ◽  
High Genetic Diversity ◽  
Acacia Melanoxylon ◽  
River Region ◽  
High Level

A study of allozyme variation in Acacia melanoxylon R. Br. in 27 populations from across the geographic range of the species indicated high genetic diversity compared to other Australian trees and plants generally. Clines of increasing genetic variability with increasing latitude were found for four measures of genetic diversity. Most of the genetic diversity is found within populations but there was an unusually high level of the variation between populations (37.7%). A distinct genetic separation between the northern and southern populations was located approximately at the Hunter River region, where there is also a disjunction in the distribution of the species. The Nei (1978) genetic distance between these populations within this species is larger than observed between some plant species. Clearly the species has evolved separately in the two regions for a considerable time.

Allozyme variation in three closely related species of Caucasian rock lizards (Lacerta)

1995 ◽  
Vol 16 (4) ◽  
pp. 331-340 ◽  
Author(s):  
Ross D. MacCulloch ◽  
F.D. Danielyan ◽  
Ilya S. Darevsky ◽  
Robert W. Murphy ◽  
Keyword(s):  
Genetic Diversity ◽  
Genetic Variability ◽  
Genetic Distance ◽  
Related Species ◽  
Allozyme Variation ◽  
Direct Count ◽  
Closely Related Species ◽  
Polymorphic Loci ◽  
Allozyme Loci ◽  
Insular Populations

AbstractGenetic diversity at 37 allozyme loci was surveyed from Lacerta valentini (4 populations), L. portschinskii and L. rudis (1 population each). The number of polymorphic loci ranged from 1 (L. valentini) to 11 (L. rudis). Mean heterozygosity (direct count) ranged from 0.003 (L. valentini) to 0.071 (L. rudis). Nei's (1978) genetic distance ranged from 0-0.03 among populations of L. valentini, 0.127-0.163 between L. valentini and L. rudis and 0.366-0.487 between L. portschinskii and the two other taxa. Indices of genetic variability for species having disjunct distributions were lower than in species with contiguous distributions, similar to the case of insular populations, which have lower values than do mainland populations.

Genetic diversity and population structure of red spruce (Picea rubens)

1994 ◽  
Vol 72 (12) ◽  
pp. 1778-1786 ◽  
Author(s):  
Gary J. Hawley ◽  
Donald H. DeHayes
Keyword(s):  
Genetic Diversity ◽  
Genetic Variability ◽  
Genetic Distance ◽  
Genetic Drift ◽  
Black Spruce ◽  
Allozyme Variation ◽  
Picea Rubens ◽  
Red Spruce ◽  
Isolated Populations ◽  
Cool Temperate

Allozyme variation at 36 loci was estimated for 19 populations of red spruce (Picea rubens Sarg.) from throughout its natural range. Average estimates of polymorphic loci (95% criterion), effective number of alleles per locus, and observed and expected heterozygosities are 23%, 1.13, 7.47%, and 7.89%, respectively. Mean genetic distance among populations is 0.007, and 93% of the genetic diversity resides within red spruce populations. Comparisons with other species indicate that red spruce is less genetically variable than most other north-temperate woody plant species. Observed heterozygosity varied significantly among geographic regions, with northern cool-temperate populations having the highest mean observed heterozygosity, followed by central montane populations, then southern isolated populations with the lowest observed heterozygosity. Regional differences in genetic variability could be due to several factors, including migration from different glacial refugia, introgression of red spruce with more genetically variable black spruce in areas of sympatry in the north, and genetic drift followed by higher than expected levels of inbreeding in small isolated southern red spruce populations. Based on genetic distance, northern cool-temperate red spruce are more closely related to nonintrogressed red spruce than to nonintrogressed black spruce, suggesting that introgression is not a major factor contributing to greater genetic variability in the northern portion of the red spruce range. Relatively high genetic differentiation among populations, higher than expected levels of inbreeding, and evidence of reduced gene flow among populations suggest that low genetic variability evident in southern red spruce populations may be a result of genetic drift followed by inbreeding. Key words: Picea rubens, genetic diversity, isozymes, population genetic structure.

Assessment of genetic variability amongst cultivated populations of Khasi mandarin (Citrus reticulata Blanco) detected by ISSR

2021 ◽  
pp. 1-11
Author(s):  
Karishma Kashyap ◽  
Rasika M. Bhagwat ◽  
Sofia Banu
Keyword(s):  
Genetic Diversity ◽  
Genetic Variability ◽  
Inter Simple Sequence Repeat ◽  
Northeast India ◽  
Issr Markers ◽  
Citrus Reticulata ◽  
Brahmaputra Valley ◽  
Indian Food ◽  
Cultivated Populations ◽  
High Level

Abstract Khasi mandarin (Citrus reticulata Blanco) is a commercial mandarin variety grown in northeast India and one of the 175 Indian food items included in the global first food atlas. The cultivated plantations of Khasi mandarin grown prominently in the lower Brahmaputra valley of Assam, northeast India, have been genetically eroded. The lack in the efforts for conservation of genetic variability in this mandarin variety prompted diversity analysis of Khasi mandarin germplasm across the region. Thus, the study aimed to investigate genetic diversity and partitioning of the genetic variations within and among 92 populations of Khasi mandarin collected from 10 cultivated sites in Kamrup and Kamrup (M) districts of Assam, India, using Inter-Simple Sequence Repeat (ISSR) markers. The amplification of genomic DNA with 17 ISSR primers yielded 216 scorable DNA amplicons of which 177 (81.94%) were polymorphic. The average polymorphism information content was 0.39 per primer. The total genetic diversity (HT = 0.28 ± 0.03) was close to the diversity within the population (HS = 0.20 ± 0.01). A high mean coefficient of gene differentiation (GST = 0.29) reflected a high level of gene flow (Nm = 1.22), indicating high genetic differentiation among the populations. Analysis of Molecular Variance (AMOVA) showed 78% of intra-population differentiation, 21% among the population and 1% among the districts. The obtained results indicate the existence of a high level of genetic diversity in the cultivated Khasi mandarin populations, indicating the need for preservation of each existing population to revive the dying out orchards in northeast India.

scholarly journals Microsatellite genotyping from faeces of Lontra longicaudis from southern Brazil

2009 ◽  
Vol 99 (1) ◽  
pp. 5-11 ◽  
Author(s):  
Laura I. Weber ◽  
Cintia G. Hildebrand ◽  
Anderson Ferreira ◽  
Gustavo Pedarassi ◽  
José A. Levy ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Conservation Status ◽  
Significant Degree ◽  
Southern Brazil ◽  
High Genetic Diversity ◽  
Low Degree ◽  
Faecal Samples ◽  
High Level ◽  
Degree Of Differentiation ◽  
Lontra Longicaudis

A genetic study of the neotropical river otter Lontra longicaudis (Olfers, 1818), which has an unknown conservation status, was carried out at the Taim Ecological Station and the margins of the Vargas stream, Rio Grande do Sul, southern Brazil. Faecal samples were collected, and DNA was extracted using a silica-guanidine method. Five microsatellite loci were amplified using PCR with heterologous primers previously described for Lutra lutra (Linnaeus, 1758). Sixteen faecal samples out of 29 from Taim and 11 out of 14 from Vargas stream margins contained enough DNA for genetic analysis. A total of 49 different alleles were found at both localities, from which 18 were exclusively found in individuals from Taim and 17 were exclusives from Vargas individuals. The most common allele was the same at both locations for three loci (Lut715, Lut733, and Lut818). A high level of genetic diversity was found at both sites (NeTaim=4.1, HoTaim=0.299, HeTaim=0.681; NeVargas=4.9, HoVargas=0.355, HeVargas=0.724), being higher at the Vargas stream site. A high and significant level of heterozygote deficiency was observed at most loci according to the χ2 test. The homogeneity χ2 test (P<0.001) showed that there were significant differences in the allele frequencies between the two locations. Genotyping for more than one locus was possible in 81.5% of samples, from which only 37% were possible to genotype for more than three loci. A low degree of relatedness was found among individuals from Taim (R=0.055±0.310), but an even lower value of relatedness was found at the Vargas site (R= -0.285±0.440). The significant degree of differentiation (I=0.890; F ST=0.059) found between Taim and Vargas individuals suggests that there is more than one population of otters in the southern extreme of Brazil, which probably are associated with the water body systems found in this region, the Mirim and the Caiuvá/Flores/Mangueira Lagoons. The high genetic diversity and low relatedness found at the Vargas stream, lead us to believe that the Vargas stream may be acting as a corridor between these water bodies for otter dispersion.

scholarly journals Analysis of Genetic Diversity in three Kazakh Sheep using 12 Microsatellites

2018 ◽  
Vol 7 (4.38) ◽  
pp. 122
Author(s):  
Kairat Dossybayev ◽  
Aizhan Mussayeva ◽  
Bakytzhan Bekmanov ◽  
Beibit Kulataev
Keyword(s):  
Genetic Diversity ◽  
Genetic Variability ◽  
Mean Value ◽  
Fixation Index ◽  
Merino Sheep ◽  
Str Markers ◽  
Sheep Breeds ◽  
Str Loci ◽  
High Level ◽  
Two Populations

The genetic structure of three Kazakh sheep breeds was examined by using 12 microsatellite loci. A total of 144 alleles were detected from the 12 STR loci, with a mean value of 12.0. The highest allele diversity was found at the locus CSRD247 (16 alleles). PIC value showed that all studied STR markers are more informative and appropriate for genetic analysis of three Kazakh sheep populations. Beside of INRA006, all markers had high level of genetic variability. As Fixation index shows, the excess of the heterozygosity was observed only in loci MAF065. Obtained number of private alleles in Edilbai, Kazakh Arkhar Merino and Kazakh Fine-wool sheep were 25, 17 and 15 respectively. Genetic diversity was higher in Edilbai population than in other two populations. The genetic variability was lower in Kazakh Arkhar Merino sheep than in the Edilbai and Kazakh Fine-wool sheep breeds. The genetic distance was the largest between Edilbai and Kazakh Arkhar Merinos. Also, the moderate differentiation was observed between Edilbai and Kazakh Arkhar Merinos.   

scholarly journals Using Random Amplified Polymorphic DNA to Assess Genetic Diversity and Structure of NaturalCalophyllum brasiliense(Clusiaceae) Populations in Riparian Forests

2014 ◽  
Vol 2014 ◽  
pp. 1-8
Author(s):  
Evânia Galvão Mendonça ◽  
Anderson Marcos de Souza ◽  
Fábio de Almeida Vieira ◽  
Regiane Abjaud Estopa ◽  
Cristiane Aparecida Fioravante Reis ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Genetic Variability ◽  
Random Amplified Polymorphic Dna ◽  
Natural Populations ◽  
Rio Grande ◽  
Shannon Index ◽  
High Genetic Diversity ◽  
Family Structures ◽  
Genetic Diversity And Structure ◽  
Kinship Coefficients

The objective of this study was to assess the genetic variability in two natural populations ofCalophyllum brasilienselocated along two different rivers in the state of Minas Gerais, Brazil, using RAPD molecular markers. Eighty-two polymorphic fragments were amplified using 27 primers. The values obtained for Shannon index (I) were 0.513 and 0.530 for the populations located on the margins of the Rio Grande and Rio das Mortes, respectively, demonstrating the high genetic diversity in the studied populations. Nei’s genetic diversity (He) was 0.341 for the Rio Grande population and 0.357 for the Rio das Mortes population. These results were not significantly different between populations and suggest a large proportion of heterozygote individuals within both populations. AMOVA showed that 70.42% of the genetic variability is found within populations and 29.58% is found among populations (ФST=0.2958). The analysis of kinship coefficients detected the existence of family structures in both populations. Average kinship coefficients between neighboring individuals were 0.053 (P<0.001) in Rio das Mortes and 0.040 (P<0.001) in Rio Grande. This could be due to restricted pollen and seed dispersal and the history of anthropogenic disturbance in the area. These factors are likely to contribute to the relatedness observed among these genotypes.

Relationships of Podarcis wall lizards from Algeria based on mtDNA data

2009 ◽  
Vol 30 (4) ◽  
pp. 483-492 ◽  
Author(s):  
Said Larbes ◽  
D. James Harris ◽  
Catarina Pinho ◽  
Alexandra Lima ◽  
José Carlos Brito ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Genetic Variability ◽  
Iberian Peninsula ◽  
North Africa ◽  
Southern Region ◽  
Monophyletic Group ◽  
North African ◽  
High Genetic Diversity ◽  
African Populations ◽  
Molecular Studies

AbstractRecent molecular studies indicate that Podarcis wall lizards occurring in the southern region of the Iberian Peninsula and in North Africa, from south Morocco to eastern Tunisia, constitute a monophyletic group composed of several highly differentiated forms that appear to be incipient species. However, Algerian populations, which are geographically intermediate, have not been investigated so far. In this study we determine the levels of genetic variability between Algerian populations and other North African populations, using a more extensive sampling scheme covering most of the distribution range in this area. Our results show that North African Podarcis present high genetic diversity, comprising at least five highly divergent lineages. Two of these lineages were only detected in Algeria, which harbours most of the genetic diversity found within Podarcis from North Africa.

scholarly journals ALLOZYME DIVERSITY IN CHESTNUT (CASTANEA SPP.).

HortScience ◽  
1994 ◽  
Vol 29 (7) ◽  
pp. 736a-736
Author(s):  
Hongwen Huang ◽  
Fenny Dane ◽  
Joseph Norton
Keyword(s):  
Genetic Variability ◽  
Genetic Distance ◽  
The Other ◽  
Changjiang River ◽  
Allozyme Diversity ◽  
Allele Distribution ◽  
Polymorphic Loci ◽  
The Changjiang River ◽  
Enzyme Systems ◽  
River Region

Allozyme genetic variability in three chestnut (Castanea) species was investigated using 19 loci from ten enzyme systems. G-tests of heterogeneity of isozymic allele distribution showed significant differences in both intraspecific and interspecific populations. C. mollissima was found to possess a significantly higher value of mean gene heterozygosity (H=0.3050±0.0419), percentage of polymorphic loci (P=84.21%) and average number of alleles per locus (A=2.05) than any other species in the Castanea section Eucustanon. When the genetic variability of populations of C. mollissimo from four regions in China was investigated, population from the Changjiang river region showed a markedly higher mean gene heterozygosity (H=0.3480±0.0436) than populations from the other regions. An approximately identical genetic distance between the population from the Changjiang river region and populations from three other regions was observed, while populations from the latter regions showed almost the same genetic distance from each other.

scholarly journals Assessment of Genetic Diversity and Marker-Trait Associations Using Selected Early Maize Inbreds Derived From Local Landraces of Eastern Himalayan Regions

2021 ◽  
Author(s):  
E. Lamalakshmi Devi ◽  
Umakanta Ngangkham ◽  
Akoijam Ratankumar Singh ◽  
Bhuvaneswari S ◽  
Konsam Sarika ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Agronomic Traits ◽  
Crop Improvement ◽  
Mean Value ◽  
Cross Combination ◽  
High Genetic Diversity ◽  
Average Value ◽  
Maize Inbreds ◽  
High Level ◽  
Trait Associations

Abstract North- Eastern parts of India fall under Eastern Himalayan region and it is a diversity hotspot of many crops including maize. Evaluation of genetic diversity is required to tape the potentiality of genetic resources in any crop improvement programmes. In the present study, genetic diversity at fifty two microsatellite markers were conducted in 30 early maize inbreds developed from local landraces of NE India. Genetic diversity analysis revealed a total of 189 alleles with a mean of 3.63 alleles/ locus. The allele size ranged from 50 bp (phi 036) to 295 bp (p 101049) which revealed a high level of genetic diversity among the loci. The PIC among the 30 genotypes ranged from 0.17 (umc 1622) to 0.76 (umc 1153) with an average value of 0.49. The value of Expected Heterozygosity (HExp) ranged from 0.19 to 0.80 with an average of 0.57, whereas the Observed Heterozygosity (HObs) ranged from 0 to 0.89 with a mean of 0.14.The genetic dissimilarity between the genotype pairs ranged from 0.40 to 0.64 with a mean value of 0.57. Cluster analysis grouped the 30 inbreds into distinct three sub-clusters. Similarly, population structure and principal coordinate analysis) analysis also classified the 30 inbred lines into three-subpopulations. AMOVA revealed that 6% of total variance is due to differences among populations, while 94% of total molecular variance is accounted by within populations. Marker-trait associations showed a total of twelve SSR markers significantly associated with seven agronomic traits. From the present finding, these results show that the thirty maize inbreds have high genetic diversity which would be useful for choosing promising parents and for making cross combination based on genetic distance and clustering for genetic improvement programmes of maize.

scholarly journals Genetic diversity in maize dent landraces assessed by morphological and molecular markers

Genetika ◽  
2013 ◽  
Vol 45 (3) ◽  
pp. 811-824 ◽  
Author(s):  
Danijela Ristic ◽  
Vojka Babic ◽  
Violeta Andjelkovic ◽  
Jelena Vancetovic ◽  
Snezana Mladenovic-Drinic ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Cluster Analysis ◽  
Molecular Markers ◽  
Genetic Distance ◽  
Morphological Traits ◽  
Mean Value ◽  
Ecological Data ◽  
Phenotypic Analysis ◽  
High Level ◽  
Maize Research Institute

Maize Research Institute ?Zemun Polje? genebank maintains a collection of landraces grouped into 18 agro-ecological collected from ex-Yugoslavia territories. The application and comparison of different marker systems are important for the characterization and use of maize landraces in breeding program, as potential sources of desirable traits. In this study, 15 morphological traits, 7 RAPD primers and 10 SSR primer pairs were applied to i) to determine genetic distance between 21 maize dent landraces and ii) compare results obtained on morphological and molecular markers. Phenotypic analysis showed high level of heterogeneity between landraces. Higher level of genetic diversity was obtained with SSR than with RAPD. Genetic distance mean value for RAPD data was 0.35 i.e. for SSR 0.48. Based on the morphological traits and molecular markers, unweighted pairgroup method (UPGMA) analysis was applied for cluster analysis, using statistical NTSYSpc program package. Cluster analysis of morphological and molecular markers distances did not show the same population grouping. Better agreement with agro-ecological data was obtained with RAPD markers. Correlations between dissimilarity matrices for different types of markers were low. Data obtained in this work could be useful for further study of a larger number of landraces, and conservation of genetic resources and their genetic diversity.

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