Allozyme variability in natural populations of green alder (Alnus crispa) in Quebec

Genome ◽  
1987 ◽  
Vol 29 (2) ◽  
pp. 345-352 ◽  
Author(s):  
J. Bousquet ◽  
W. M. Cheliak ◽  
M. Lalonde
Keyword(s):  
Natural Populations ◽  
Outcrossing Rate ◽  
Polymorphic Loci ◽  
Alnus Crispa ◽  
Model Average ◽  
Expected Heterozygosity ◽  
Green Alder ◽  
Hardy Weinberg Equilibrium ◽  
Fixation Indices ◽  
Sexually Mature

Vegetative and sexual tissues from 22 populations of Alnus crispa (Ait.) Pursh (green alder, Betulaceae) in Quebec were analyzed for electrophoretically demonstrable diversity of 11 enzymes encoded by 16 structural loci in sexually mature populations. Of these 16 loci, 9 were found polymorphic. A total of 28 different alleles were detected with no more than three alleles per locus. No two-locus linkage disequilibrium was observed between eight polymorphic loci analyzed. Assuming a diploid model, average level of expected heterozygosity was 0.14 in the mature generation, with nearly all populations in Hardy–Weinberg equilibrium for the set of polymorphic loci investigated. Mean outcrossing rate was 0.95. Fixation indices revealed low inbreeding with no specific subpopulation structure. Hence, an important level of gene flow would exist within the populations. Without any strong evidence for polyploidy, and in the light of results obtained, the species could be classified equally well as a diploid or a diploidized allotetraploid. Key words: actinorhizal plant, alder, allozymes, Alnus, fixation indices, heterozygosity, outcrossing rate, polyploidy.

Genetic analysis of Cheirostylis species based on microsatellite markers

2014 ◽  
Vol 13 (3) ◽  
pp. 286-289 ◽  
Author(s):  
Supajit Sraphet ◽  
Anuwat Saengsri ◽  
Duncan R. Smith ◽  
Kanokporn Triwitayakorn
Keyword(s):  
Genetic Analysis ◽  
Microsatellite Markers ◽  
Genomic Dna ◽  
Polymorphic Loci ◽  
Dna Library ◽  
Expected Heterozygosity ◽  
Unknown Species ◽  
Genomic Dna Library ◽  
Hardy Weinberg Equilibrium ◽  
Conservation Plan

Microsatellite markers specific to Cheirostylis yunnanensis Rolfe were developed using an enriched genomic DNA library technique. The library was constructed using (AG)20 and (CAG)20 oligonucleotide repeats. A total of 48 primer pairs were designed and tested with 48 C. yunnanensis Rolfe samples, resulting in 11 polymorphic loci. The number of alleles per locus ranged from 2 to 12, with an average of six alleles. The observed and expected heterozygosity ranged from 0.0426 to 0.8085 and 0.0421 to 0.9078, respectively. Of the 11 polymorphic loci, three showed a significant deviation from Hardy–Weinberg equilibrium and one exhibited linkage disequilibrium. Cross-species amplification was tested with five samples of Cheirostylis of unknown species resulting in eight loci that could be amplified, with the number of alleles ranging from one to two. The microsatellite markers developed in this study will be useful for the genetic analysis of C. yunnanensis in order to differentiate species as well as to establish a conservation plan for this species.

Allozyme genetic diversity among Fagus grandifolia trees resistant or susceptible to beech bark disease in natural populations

2000 ◽  
Vol 30 (5) ◽  
pp. 778-789 ◽  
Author(s):  
Daniel B Houston ◽  
David R Houston
Keyword(s):  
Prince Edward Island ◽  
Natural Populations ◽  
Fagus Grandifolia ◽  
Population Diversity ◽  
Beech Bark Disease ◽  
Polymorphic Loci ◽  
Expected Heterozygosity ◽  
Disease Occurrence ◽  
Dormant Bud ◽  
Natural Stands

American beech (Fagus grandifolia Ehrh.) trees resistant (R = 760) and susceptible (S = 681) to beech bark disease were located and mapped in nine natural stands in West Virginia (WV), Massachusetts (MA), Maine (ME), Nova Scotia (NS), and Prince Edward Island (PEI). Dormant bud tissue collected from each tree was examined by isozyme analysis to characterize the population genetic structure of R and S subpopulations mapped in each of four intensively sampled (R/S) stands, and five additional populations in which only R trees were sampled. Seventeen enzymes (with 9 polymorphic and 14 monomorphic loci) were analyzed to estimate variation across the spatial range of disease occurrence. All populations possessed significant levels of inter- and intra-population diversity; several parameters appeared to increase in magnitude from southwest to northeast across the range. In the R/S stands, percent polymorphic loci averaged 38%, average number of alleles/locus was 1.8 (3.0 for polymorphic loci), and mean expected heterozygosity was 0.165. Most genetic variation resided within populations (97%; GST = 0.03). Analyses of pooled R and S subpopulations demonstrated that observed heterozygosities were up to 26% higher in S trees, i.e., R tree populations exhibited consistent heterozygote deficits.

scholarly journals Allozyme Based Genetic Variation between Hatchery and Natural Populations of Sahar (Tor putitora)

2015 ◽  
Vol 26 ◽  
pp. 212-223
Author(s):  
Suresh K Wagle ◽  
Neeta Pradhan ◽  
Tek B Gurung ◽  
Jay D Bista
Keyword(s):  
Genetic Variation ◽  
First Generation ◽  
Biological Diversity ◽  
Anthropogenic Activities ◽  
Natural Populations ◽  
Effective Population ◽  
Polymorphic Loci ◽  
Tor Putitora ◽  
Two Generations ◽  
Hardy Weinberg Equilibrium

Sahar (Tor putitora) formed a substantial natural fishery in the major riverine and lacustrine ecosystem of Nepal. Biological diversity of this species is being threatened by various anthropogenic activities. In view of the conservational value and the aquaculture potential of T. putitora, significant development in artificial propagation of this species has been achieved. The successful hatchery production of T. putitora brought to the forefront problematic questions regarding genetic variation of the hatchery stocks. A study was, therefore, conducted to determine the genetic variability within and between hatchery stocks and their wild counterparts of T. putitora using allozyme markers.Analyses of seven enzyme systems resuled in 11 loci being resolved from lake population and two consecutive generations of hatchery populations of T. putitora. Based on five polymorphic loci, all populations had percentage polymorphic loci 45.45. Significant reduction (P<0.01) in number of alleles per locus was evident in hatchery populations (1.45 ±0.181) compared to lake population (1.72 ±0.90). Loss of rear alleles, EST-2*74, IDH*70 and GDH*33 occurred in both of the hatchery populations which were present in wild counterparts- the lake population. All populations under study conform to the Hardy-Weinberg equilibrium at the 1% level. Although not significant (P>0.05), observed heterozygosity increased in first generation of hatchery population (Ho= 0.181 ±0.233) compared to natural population (Ho=0.179±0.221). The Ho of second generation of hatchery population was lowest (0.119 ±0.143) among the populations studied. Loss of rare alleles from the two generations of hatchery population, while these alleles were present in corresponding natural populations suggested the founders (20-30 individuals) of the hatchery populations probably represented bottlenecks to very small effective population size (Ne).J. Nat. Hist. Mus. Vol. 26, 2012: 212-223  

Comparison of the allozyme diversity in several populations of Chamaecyparisformosensis and Chamaecyparistaiwanensis

1994 ◽  
Vol 24 (10) ◽  
pp. 2128-2134 ◽  
Author(s):  
Tsan-Piao Lin ◽  
Tzen-Yu Lee ◽  
Li-Feng Yang ◽  
Yong-Ly Chung ◽  
Jenq-Chuan Yang
Keyword(s):  
Population Variation ◽  
Fixation Index ◽  
Effective Number ◽  
Allozyme Diversity ◽  
Polymorphic Loci ◽  
Average Percentage ◽  
Expected Heterozygosity ◽  
Hardy Weinberg Equilibrium ◽  
Different Populations ◽  
One Year

Genetic diversity within and genetic differentiation among three populations of Chamaecyparisformosensis Matsum. and two populations of Chamaecyparistaiwanensis Masam. & Suzuki were investigated using one-year-old seedlings collected from central and northern Taiwan. For C. formosensis 330 seedlings from 33 seed trees were used, while for C. taiwanensis 260 seedlings from 26 seed trees were used. Eleven enzyme systems were investigated. In C. formosensis, 5 of the 21 loci examined were polymorphic. The average percentage of polymorphic loci per population was 20.6% at the 99% criterion for polymorphism. Mean expected heterozygosity ranged from 0.079 to 0.100 in the different populations. On average, there were 6.6 to 9.2% heterozygous loci per individual and 1.24 to 1.29 alleles per locus; the effective number of alleles per locus ranged from 1.09 to 1.11. In C. taiwanensis, 7 of the 20 loci examined were polymorphic and the average percentage of polymorphic loci per population was 22.5%. Mean expected heterozygosity ranged from 0.044 to 0.060. On average there were 4.5 to 5.6% heterozygous loci per individual and 1.45 alleles per locus; the effective number of alleles per locus ranged from 1.05 to 1.08. The surprisingly low expected heterozygosity and percentage of polymorphic loci compared with other conifer probably reflects the insular nature of these species. Partitioning the genetic variability into within- and among-population components with F-statistics led to an estimate of within-population variation of 95% of the total variation in both C. formosensis and C. taiwanensis. Chamaecyparisformosensis had a positive fixation index (0.109) that was significantly different from zero at the 5% level, indicating that most loci have slightly higher frequencies of homozygotes. Chamaecyparistaiwanensis, however, had a fixation index close to zero (0.036), which suggests that most loci are in Hardy–Weinberg equilibrium. The genetic distance between C. formosensis and C. taiwanensis was 0.70, which clearly separates these two species.

scholarly journals ISOLATION AND CHARACTERIZATION OF NEW MICROSATELLITE MARKERS FOR THE CORTÉS GEODUCK (Panopea globosa)

2016 ◽  
Vol 31 (1) ◽  
pp. 17
Author(s):  
Celia Isabel Bisbal -Pardo ◽  
Miguel Ángel Del Río -Portilla ◽  
Ana Yonori Castillo -Paéz ◽  
Axayácatl Rocha-Olivares
Keyword(s):  
Fishery Management ◽  
Genetic Research ◽  
Isolation And Characterization ◽  
Expected Heterozygosity ◽  
Tetranucleotide Repeats ◽  
Hardy Weinberg Equilibrium ◽  
Increasing Demand ◽  
Sustainable Fishery ◽  
Generation Technology

The geoduck Panopea globosa is a long-lived and large endemic infaunal clam sustaining a growing fishery in the Northwest coast of México that, in spite of its increasing demand in Asian markets very little is known about its biology. In order to provide genetic markers to support genetic research of wild populations, nine novel microsatellite loci (di-, tri-, and tetranucleotide repeats) were developed using shotgun sequencing with next generation technology (Illumina). The number of alleles per locus ranged from 3 to 16 and the observed and expected heterozygosity ranged from 0.286 to 0.650 and 0.504 to 0.906, respectively. Five loci were found to be significantly deviated from the Hardy-Weinberg equilibrium and three pairs showed evidence of linkage disequilibrium. Most loci are highly informative for population genetics and linkage analyses according to their polymorphism information content (> 0.5) and will be useful for increasing our understanding of the wild population structure and developing a sustainable fishery management. Aislamiento y caracterización de nuevos marcadores microsatelitales en la almeja generosa (Panopea globosa) La almeja generosa Panopea globosa es una especie infáunica longeva y de gran tamaño que mantiene una pesquería creciente en la costa del Noroeste de México. A pesar de su demanda creciente en los mercados asiáticos, se conoce muy poco acerca de su biología. Con la finalidad de proveer nuevos marcadores genéticos para la caracterización de poblaciones silvestres, se desarrollaron nueve marcadores microsatelitales nuevos (con patrones repetidos de di-, tri-, y tetranucleotídicos) utilizando secuenciación genómica aleatoria con tecnología de secuenciación de siguiente generación (Illumina). El número de alelos por locus varió de 3 a 16 y los valores de heterocigosidad observada y esperada variaron de 0.286 a 0.650 y 0.504 a 0.906, respectivamente. Cinco microsatelites se desvían del equilibrio de Hardy-Weinberg y tres pares de microsatélites mostraron evidencia de desequilibrio de ligamiento. La mayoría de los loci son altamente informativos para estudios poblacionales y análisis de ligamiento de acuerdo con su contenido de información de polimorfismos (> 0.5) y serán útiles para incrementar el conocimiento de la estructura genética de las poblaciones silvestres de esta almeja y para coadyuvar en su pesquería sustentable.

scholarly journals Genetic analysis of silver-fir populations in the Beskids

2011 ◽  
Vol 72 (2) ◽  
pp. 115-119 ◽  
Author(s):  
Leon Mejnartowicz
Keyword(s):  
Genetic Diversity ◽  
Genetic Variation ◽  
Genetic Analysis ◽  
Abies Alba ◽  
Genetic Distances ◽  
Silver Fir ◽  
Geographical Distance ◽  
Polymorphic Loci ◽  
Expected Heterozygosity ◽  
Rare Alleles

Twenty-eight isozymic loci were studied in the Beskid Mts., in four populations of common silver-fir (<em>Abies alba</em>): one in Beskid Makowski (BM) and three populations in Beskid Sądecki (BS). Their genetic variation and diversity were analyzed, and Nei's genetic distances between the populations were calculated. The results show that the geographical distance between the BM population and the three BS populations is reflected in genetic distances. The BM population is clearly distinct from the others. It has the lowest genetic diversity (<em>I</em> = <em>0.42</em>), percentage of polymorphic loci <em>(%PoL </em>= <em>64.29</em>) and number of rare alleles (<em>NoRa </em>= <em>5</em>). Besides, the BM population has the highest observed heterozygosity (<em>Ho </em>= <em>0.291</em>), which exceeds the expected heterozygosity (<em>He </em>= <em>0.254</em>), estimated on the basis of the Hardy-Weinberg Principle. On the contrary, BS populations are in the state of equilibrium, which is manifested, in similar values of <em>He </em>= <em>0.262 </em>and <em>Ho </em>= <em>0.264</em>.

STUDIES OF NATURAL POPULATIONS OF MUS. V. A SURVEY OF NINE LOCI FOR POLYMORPHISMS

1969 ◽  
Vol 11 (3) ◽  
pp. 497-513 ◽  
Author(s):  
M. L. Petras ◽  
J. D. Reimer ◽  
F. G. Biddle ◽  
J. E. Martin ◽  
R. S. Linton
Keyword(s):  
Geographic Distribution ◽  
Mus Musculus ◽  
Additional Data ◽  
Natural Populations ◽  
House Mice ◽  
Polymorphic Loci

An examination of house mice (Mus musculus) from a number of sites in southwestern Ontario revealed six loci (Hbb, Es-2, Es-3, Es-5, Ldr-1 and A) to be polymorphic and three (Es-1, Pro-1 and Trf-1) to be monomorphic. A comparison of the Ontario samples with samples from southeastern Michigan suggests that the polymorphisms detected are common to Mus populations in both regions and are relatively stable. Data reported by other investigators suggest that some of these polymorphisms have a broad geographic distribution. Also discussed are findings of loci described elsewhere. Two of these T and Ea-1, are polymorphic in some of the populations under consideration. General conclusions include: (1) that polymorphic loci are probably as frequent in mouse populations as in Drosophila and man; (2) that the polymorphisms observed are relatively stable and widespread; (3) that some of the alleles responsible for the polymorphisms observed are not neutral; and (4) that additional data are necessary to elucidate the mechanisms responsible for the polymorphisms observed.

Evidence of high self-fertilization in natural populations of eastern white cedar (Thuja occidentalis)

1990 ◽  
Vol 68 (3) ◽  
pp. 663-668 ◽  
Author(s):  
Daniel J. Perry ◽  
Peggy Knowles
Keyword(s):  
Natural Populations ◽  
Outcrossing Rate ◽  
Significant Heterogeneity ◽  
Embryo Survival ◽  
Thuja Occidentalis ◽  
White Cedar ◽  
Northwestern Ontario ◽  
Outcrossing Rates ◽  
Self Fertilization ◽  
Eastern White Cedar

Arrays of open-pollinated seeds were assayed for allozyme polymorphisms at four loci (Mdh-1, Me, 6Pg-2, and Pgm) to obtain estimates of outcrossing rates for three eastern white cedar populations in northwestern Ontario, Canada. Multilocus population outcrossing rate estimates were low, ranging from 0.507 to 0.745, with significant heterogeneity among populations. Low stand densities and relatively high selfed embryo survival may have contributed to the low effective outcrossing rates observed. Single-tree multilocus outcrossing rate estimates were obtained for nine trees from one population. When estimated jointly with outcross pollen pool allele frequencies, these outcrossing rate estimates ranged from 0.253 to 1.023 with significant heterogeneity among trees. Key words: mating system, outcrossing rate, Thuja occidentalis L.

scholarly journals Genetic diversity in natural populations of Buriti (Mauritia flexuosa L. f.)

2011 ◽  
Vol 11 (3) ◽  
pp. 216-223 ◽  
Author(s):  
Liene Rocha Picanço Gomes ◽  
Maria Teresa Gomes Lopes ◽  
Jania Lilia da Silva Bentes ◽  
Willian Silva Barros ◽  
Pedro de Queiroz Costa Neto ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Length Polymorphism ◽  
Fragment Length Polymorphism ◽  
Natural Populations ◽  
Analysis Of Molecular Variance ◽  
Molecular Variance ◽  
Polymorphic Loci ◽  
Mauritia Flexuosa ◽  
Geographical Distances ◽  
Traditional Communities

This study aimed to characterize the genetic diversity of buriti populations by AFLP (Amplified Fragment Length Polymorphism) markers. The analysis was performed in four populations used by traditional communities in the state of Amazonia (Bom Jesus do Anamã, Lauro Sodré, Santa Luzia do Buiçuzinho, and Esperança II). From each population 30 plants were randomly selected. To obtain the markers four primer combinations were used. The percentage of polymorphic loci was estimated, the molecular variance among and within populations analyzed and a dendrogram constructed. The primers detected 339 polymorphic loci ranging from 81.1 % to 91.1 % among populations. Analysis of molecular variance attributed 77.18 % to variation within and 22.8 % to variation between populations. The dendrogram indicated the formation of two groups, showing that the populations of Bom Jesus do Anamã and Lauro Sodré are genetically most similar and thet the genetic and geographical distances are not correlated.

scholarly journals Inter- and intra-population variation of local maize (Zea mays L.) populations from Slovakia and Czech Republic

2008 ◽  
Vol 43 (No. 1) ◽  
pp. 7-15 ◽  
Author(s):  
P. Múdry ◽  
J. Kraic
Keyword(s):  
Zea Mays ◽  
Genetic Variation ◽  
Czech Republic ◽  
Population Variation ◽  
Polymorphic Loci ◽  
Maize Populations ◽  
Expected Heterozygosity ◽  
Isoenzyme Polymorphism ◽  
New Alleles

Evaluation of genetic variation was performed within 62 local maize populations originating from Slovakia and Czech Republic. In total 48 alleles at 22 analyzed isoenzyme loci with an average of 2.2 alleles per locus were revealed. The percentage of polymorphic loci ranged from 14% to 59% and the frequencies of detected alleles varied from null to four per locus. No polymorphism was detected at the loci <i>Dia2</i>, <i>Got3</i>, <i>Mdh4</i>, <i>Mmm</i>, and <i>Pgm1</i>. The highest number of alleles (four) was detected at loci <i>Acp1</i>, <i>Cat3</i>, <i>Pgm2</i>. No new alleles were identified, nevertheless the frequency of seven alleles was only about 1%. The expected heterozygosity ranged from null to 0.492 with an average of 0.197. The revealed isoenzyme polymorphism confirmed that all analyzed populations were heterogeneous and as many as 17 of them were completely heterogeneous. None of the analyzed populations was identical in the frequency of alleles at all 22 analyzed loci.

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