A Cline in Genetic Diversity in River She-Oak Casuarina cunninghamiana

1989 ◽  
Vol 37 (2) ◽  
pp. 169 ◽  
Author(s):  
GF Moran ◽  
JC Bell ◽  
JW Turnbull
Keyword(s):  
Genetic Diversity ◽  
Significant Positive Correlation ◽  
Population Level ◽  
Geographic Range ◽  
Northern Territory ◽  
Height Growth ◽  
Western Population ◽  
Casuarina Cunninghamiana ◽  
Total Genetic Diversity ◽  
Allozyme Loci

Twenty populations of Casuarina cunninghamiana Miq. covering its large geographic range were used in a study of genetic diversity. Genetic variation was measured by analysing 19 allozyme loci using 50 seedlings from each of the populations. The overall genetic diversity (HT = 0.287) in C. cunninghamiana is high compared to many other plant species. A significant fraction (26.4%) of the total genetic diversity could be apportioned among populations. This genetic differentiation between populations was not random. Populations in the eastern part of the range had high correlation (r = 0.91) of genetic diversity with latitude and this involved changes in allelic frequencies at several loci. At the population level, there was a significant positive correlation between genetic diversity and 1 year height growth. The western population from King River in the Northern Territory was very distinct genetically from all the other populations and this supported previous suggestions that the northwest part of the range is occupied by a different race of the species.

Microgeographical Patterns of Allozyme Variation in Casuarina cunninghamiana Miq Within and Between the Murrumbidgee and Coastal Drainage Systems

1989 ◽  
Vol 37 (2) ◽  
pp. 181 ◽  
Author(s):  
NJ Moore ◽  
GF Moran
Keyword(s):  
Genetic Diversity ◽  
Large Population ◽  
Drainage System ◽  
Allozyme Variation ◽  
Distance Measures ◽  
Drainage Systems ◽  
Casuarina Cunninghamiana ◽  
Total Genetic Diversity ◽  
Geographic Clustering

Within the Murrumbidgee drainage system, 100 seedlings from each of 14 populations of Casuarina cunninghamiana were assayed for their allozyme genotypes at 14 loci. The levels of genetic variation were fairly similar in all populations. There was no geographic clustering of populations based on genetic distance measures. Only 3.8% of the total genetic diversity could be apportioned among populations within the drainage system. In six additional populations, branchlets from 50 trees per population were assayed for their allozyme genotypes at 27 loci. Three populations were from the Murrumbidgee drainage system and each of the others from a different coastal drainage. The mean expected heterozygosities for coastal and inland zones were 0.139 and 0.093 respectively. Of the total genetic diversity 10.7% could be apportioned among the four drainages. The results of this study suggest that for in situ conservtion of C. cunninghamiana within a region, more emphasis should be placed on conserving one large population from each major drainage system rather than a number of populations within one or two drainage systems.

Allozyme variation and population structure of Carex humilis var. nana (Cyperaceae) in Korea

2001 ◽  
Vol 79 (4) ◽  
pp. 457-463 ◽  
Author(s):  
Man Kyu Huh
Keyword(s):  
Genetic Diversity ◽  
Population Structure ◽  
Genetic Variation ◽  
North American ◽  
Population Level ◽  
Allozyme Variation ◽  
Population Divergence ◽  
Geographic Ranges ◽  
The Mean ◽  
Allozyme Loci

Genetic diversity and population structure of 22 Carex humilis var. nana Ohwi (Cyperaceae) populations in Korea were determined using genetic variation at 23 allozyme loci. This is a long-lived herbaceous species with a widespread distribution in eastern Asia. The 12 enzymes revealed 23 putative loci, of which 11 were polymorphic (47.8%). Genetic diversity at the varietal level and at the population level was 0.131 and 0.118, respectively. Total genetic diversity (HT = 0.274) and within population genetic diversity (HS = 0.256) were high, whereas the extent of the population divergence was relatively low (GST = 0.068). An indirect estimate of the number of migrants per generation (Nm = 3.42) indicated that gene flow was high among Korean populations. Wide geographic ranges, perennial herbaceous nature, and the persistence of multiple generations are associated with the high level of genetic variation. A distinct difference between Asian and North American Carex is shown in the proportion of genetic variation (GST) (p < 0.001). The mean GST of Asian Carex was estimated as 0.056; thus, only 5.6% of genetic variability was distributed among populations, whereas the mean GST of North American Carex was estimated as 19.5% (3.5 times higher). It is probable that the geographical distance between population pairs and presence or absence of glacial history may play roles in the substantial difference between both groups.Key words: Carex humilis var. nana, genetic diversity, population structure.

The genetic structure and the conservation of the five natural populations of Pinusradiata

1988 ◽  
Vol 18 (5) ◽  
pp. 506-514 ◽  
Author(s):  
G. F. Moran ◽  
J. C. Bell ◽  
K.G. Eldridge
Keyword(s):  
Genetic Diversity ◽  
Natural Populations ◽  
Allozyme Variation ◽  
Conservation Strategies ◽  
Mainland Population ◽  
Island Populations ◽  
Expected Heterozygosity ◽  
Environmental Criteria ◽  
Total Genetic Diversity ◽  
Allozyme Loci

Pinusradiata is restricted to three mainland coastal populations in California and two island populations off Baja California, Mexico. In this study each population was divided into two geographic stands based on natural disjunctions within populations. In addition to the division mentioned above, each mainland population was also divided into a number of ecological stands based on ecological and environmental criteria. Genetic variation was measured by analysing 31 allozyme loci electrophoretically using germinated seed from 272 families across all stands and populations. Moderate levels of allozyme variation were found as shown by population averages for mean number of alleles per locus (1.79), percent polymorphic loci (46.4%, 0.99 criterion), and expected heterozygosity (0.098). In fact, the overall genetic diversity in P. radiata (HT = 0.117) is low compared with that of other conifers. In comparison with populations, the levels of allozyme variation in both ecological and geographic stands were slightly lower (means across ecological stands: A = 1.56, P = 39.3%, and He = 0.095). Of the total genetic diversity in P. radiata, 16.2% could be apportioned between populations, a high proportion for a conifer. In contrast, only 2.0 and 1.3% of the genetic diversity on average within mainland populations was between ecological and geographic stands, respectively. These results indicate a low level of genetic differentiation within populations, at least based on the ecological or geographic criteria used in this study. The implications and usefulness of these findings for the development of insitu conservation strategies are discussed.

scholarly journals Assessment of Genetic Diversity and Population Structure of the Endangered Astragalus exscapus subsp. transsilvanicus through DNA-Based Molecular Markers

Plants ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 2732
Author(s):  
Katalin Szabo ◽  
Doru Pamfil ◽  
Alexandru Sabin Bădărău ◽  
Monica Hârţa
Keyword(s):  
Genetic Diversity ◽  
Population Structure ◽  
Diversity Index ◽  
Gene Diversity ◽  
Population Level ◽  
Conservation Strategy ◽  
Limited Information ◽  
Subspecies Level ◽  
Total Genetic Diversity ◽  
Fragmentation Processes

Astragalus exscapus L. subsp. transsilvanicus (Schur) Nyár. (Fabaceae) is a rare plant endemic to the Transylvanian Plateau, represented by 24 identified populations. Limited information on the genetic variation and population structure is available, which obstructs efficient measures for conservation strategy. The present study aimed to analyze the genetic diversity and population structure of eight populations of A. exscapus subsp. transsilvanicus revealed by sequence-related amplified polymorphism (SRAP) markers. A total of 164 bands were amplified, 96.7% of which (159) were polymorphic. Nei’s gene diversity index (He) was estimated to be 0.228 at the population level and 0.272 at the subspecies level. The genetic differentiation among populations (Gst) was 0.165, which indicated a low proportion of total genetic diversity. The analysis of molecular variance (AMOVA) indicated that 17% of the total variation of A. exscapus subsp. transsilvanicus is found among the populations, while 83% was found within the populations. A UPGMA dendrogram, principal coordinate analysis, and the STRUCTURE software grouped the populations into two clusters uncorrelated with the provenience of the 125 individuals, which might be attributed to fragmentation processes, insect pollination, population size, and specific environmental conditions of the habitats.

Allozyme Variation and Population Substructuring in the Caucasian Ground Lizards Lacerta derjugini and Lacerta praticola

2011 ◽  
Vol 4 (2) ◽  
pp. 115-119 ◽  
Author(s):  
Ross D. MacCulloch ◽  
Ilya S. Darevsky ◽  
Robert W. Murphy ◽  
Jinzhong Fu
Keyword(s):  
Genetic Diversity ◽  
Allozyme Variation ◽  
Close Proximity ◽  
Geographic Separation ◽  
Population Substructuring ◽  
Allozyme Loci ◽  
Two Populations

Genetic diversity at 35 allozyme loci was surveyed in Lacerta derjugini (3 populations) and L. praticola (2 populations). Indices of variability were consistent with those found in other Caucasian Lacerta. There was little genetic substructuring between two populations of L. praticola despite considerable geographic separation. Conversely, populations of L. derjugini in close proximity to one another exhibited considerable substructuring.

scholarly journals Genetic diversity of Avena strigosa Schreb. ecotypes on the basis of isoenzyme markers

2009 ◽  
Vol 15 (1) ◽  
pp. 23-28 ◽  
Author(s):  
Katarzyna Kubiak
Keyword(s):  
Genetic Diversity ◽  
Genetic Similarity ◽  
Avena Strigosa ◽  
Total Genetic Diversity ◽  
Geographical Regions ◽  
The World ◽  
Total Variability ◽  
The Mean ◽  
Intrapopulation Diversity ◽  
Very High

Genetic diversity ofAvena strigosaSchreb. ecotypes on the basis of isoenzyme markersGenetic diversity was analyzed in 19 ecotypes of the diploid oatA. strigosaoriginating from various geographical regions of the world. Six isoenzyme systems (AAT, ACP, EST, LAP, MDH, PX) were studied and 16 loci were identified. Only two loci (Est4andMdh2) were polymorphic. Ecotypes were characterized by the percentage of polymorphic loci (P=3.3%), the mean number of alleles per locus (A=1.04) and intrapopulation diversity (HS=0.013). Total genetic diversity (HT=0.07) and interpopulation diversity (DST=0.057) were examined as well. The value of the coefficient of gene differentiation (GST=0.821) indicated that diversity among populations was an important contributor to total variability. Genetic similarity betweenA. strigosapopulations was very high (IN=0.94). Cluster analysis did not demonstrate strongly differentiated groups among the ecotypes examined.

Quantification of genetic diversity at allozyme loci

1997 ◽  
Vol 27 (3) ◽  
pp. 415-424 ◽  
Author(s):  
E E Berg ◽  
J L Hamrick
Keyword(s):  
Genetic Diversity ◽  
Allozyme Loci

Comparison of Allozyme and Mitochondrial DNA Variation in Populations of Walleye, Stizostedion vitreum

1989 ◽  
Vol 46 (12) ◽  
pp. 2074-2084 ◽  
Author(s):  
Robert D. Ward ◽  
Neil Billington ◽  
Paul D. N. Hebert
Keyword(s):  
Mitochondrial Dna ◽  
Glacial Refugia ◽  
Divergence Times ◽  
Stizostedion Vitreum ◽  
Dna Variation ◽  
Mtdna Variation ◽  
Mtdna Haplotypes ◽  
Total Genetic Diversity ◽  
Allozyme Loci ◽  
Organelle Genes

Twelve populations of walleye (Stizostedion vitreum) from the Great Lakes and three populations from northern Manitoba were screened for allozyme and mitochondrial DNA (mtDNA) variation. Nine enzyme loci known to show genetic variation were screened in all fish: five of them (Prot-4, Prot-2, Mdh-3, Idh-1, Adh) showed appreciable polymorphism. MtDNA was examined in all fish using six endonucleases that detected polymorphic sites and a further 13 endonucleases that detected only monomorphic sites. Only one of the allozyme loci (Prot-4) showed evidence of geographic patterning of allele frequencies. By contrast, the mtDNA haplotypes showed clear geographic variation. The proportion of total genetic diversity attributable to population differentiation (Gst) was three to five times greater for mtDNA than for the allozymes. Gst values for organelle genes are expected on theoretical grounds to be greater than for nuclear genes, and this expected difference may be enhanced in walleye because of the likelihood that, in this species, male-mediated gene flow exceeds that of females. The distributions of mtDNA haplotypes and estimated divergence times are consistent with the derivation of extant walleye populations from three different glacial refugia.

scholarly journals Intraspecific differentiation of Reed Grass Calamagrostis arundinacea (L.) Roth (Poaceae) populations revealed by peroxidase allozymes

2011 ◽  
Vol 77 (4) ◽  
pp. 299-304
Author(s):  
Maria Krzakowa ◽  
Zbigniew Celka
Keyword(s):  
Genetic Diversity ◽  
Genetic Parameters ◽  
Electrophoretic Analysis ◽  
Fixation Index ◽  
Mean Values ◽  
Interpopulation Variability ◽  
Total Genetic Diversity ◽  
Variability Level ◽  
Hardy Weinberg Equilibrium ◽  
Geographic Regions

The genetic Variation of Reed Grass <em>Calamagrostis arundinacea</em> (L.) Roth was investigated in 25 populations in various geographic regions of Poland. A total of 907 individuals were sampled for electrophoretic analysis of peroxidase loci (11 allozymes). Populations were characterised by genetic parameters e.g. heterozygosity level, Wright's fixation index (F) and polymorphism coefficient (Pg). Mean values of interpopulation variability level (GST=0.0310), total genetic diversity (HT=0.4102) and gene flow between populations (Nm=7.805) were also examined. All the populations were polymorphic and they remain in Hardy Weinberg equilibrium.

scholarly journals Genetic Diversity Studies in MAGIC Population of Soybean (Glycine max (L.) Merrill) Based on Mahalanobis D2 Distance

2021 ◽  
pp. 18-25
Author(s):  
Bidush Ranjan Swar ◽  
V. Swarnalatha ◽  
M. Rajendar Reddy ◽  
S. Vanisree
Keyword(s):  
Genetic Diversity ◽  
Seed Weight ◽  
Quantitative Traits ◽  
Genetic Recombination ◽  
Breeding Programs ◽  
Total Genetic Diversity ◽  
Glycine Max L ◽  
Diversity Studies ◽  
100 Seed Weight ◽  
Number Of Branches

Soybean MAGIC lines are highly variable breeding material which utilizes both recent and historic genetic recombination events. Present investigation was carried out to assess the genetic diversity present among 95 soybean MAGIC lines along with six checks for 10 different quantitative traits. All the genotypes were grouped into 16 clusters by performing Tocher’s clustering method using Mahalanobis D2 distance. Cluster I was the largest comprising of 30 genotypes followed by cluster II (23 genotypes), cluster X (15 genotypes) and cluster IX (9 genotypes). The maximum genetic distance (D2) was observed between cluster XI and XV (168.37) followed by cluster III and XV (164.3), cluster X and XV (149.64) as well as between cluster XII and cluster XVI (145.99). The cluster mean for most of the traits were high in cluster I and cluster XVI. Oil content contributed maximum (23.86%) towards total genetic diversity followed by number of pods plant-1 (18.97%), seed yield plant-1 (18.63%), 100 seed weight (11.05%) and number of branches plant-1 (10.16%) traits. The soybean MAGIC lines belong to the cluster XI (6-120) and cluster XV (6-30, 6-31, 6-5) were found to be the most divergent hence can be utilised in the recombination breeding programs to exploit maximum heterosis.

Sign in / Sign up

Export Citation Format

Share Document