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Mitochondrial DNA variation in natural populations of Japanese larch (Larix kaempferi)

. BONEN (1993): Inheritance of mitochondrial DNA in the conifer Larix. Theoretical and Applied Genetics 86: 383-388. DONG, J. and D. B. WAGNER (1993): Taxonomic and population differentiation of mitochondrial diversity in Pinus banksiana and Pinus contorta. Theoretical and Applied Genetics 86: 573-578. ENNOS, R. A. (1994): Estimating the relative rates of pollen and seed migration among plant populations. Heredity 72: 250-259. GAMACHE, I., J. P. JARAMILLO-CORREA, S. PAYETTE and J. BOSQUET (2003): Diverging patterns of

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Genetic structure and diversity in Juniperus communis populations in Saxony, Germany

Abstract

In recent years, land use changes led to a rapid decline and fragmentation of J. communis populations in Germany. Population isolation may lead to a restricted gene flow and, further, to negative effects on genetic variation. In this study, genetic diversity and population structure in seven fragmented J. communis populations in Saxony, Germany, were investigated using nuclear microsatellites (nSSR) and chloroplast single nucleotide polymorphism (cpSNP). In all Saxony J. communis populations, a high genetic diversity was determined but no population differentiation could be detected whatever method was applied (Bayesian cluster analysis, F-statistics, AMOVA). The same was true for three J. communis out-group samples originating from Italy, Slovakia and Norway, which also showed high genetic diversity and low genetic differences regarding other J. communis populations. Low genetic differentiation among the J. communis populations ascertained with nuclear and chloroplast markers indicated high levels of gene flow by pollen and also by seeds between the sampled locations. Low genetic differentiation may also provide an indicator of Juniper survival during the last glacial maximum (LGM) in Europe. The results of this study serve as a basis for the implementation of appropriate conservation measures in Saxony.

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Analysis of the Genetic Diversity and Population Structure of Latvian Ash (Fraxinus excelsior L.) Stands using Nuclear and Chloroplast SSR Markers

. Ecol. , 8 , 160–163. Chapuis, M. P., Estoup, A. (2007). Microsatellite null alleles and estimation of population differentiation. Mol. Biol. Evol. , 24 (3), 621–631. Dambis, J., Zilgalvis, J., Muceniece, A. (2007). Vēsturiskie dārzi un parki [Historical Gardens and Parks]. Valsts Kultūras pieminekļu aizsardzības inspekcija, Rīga. 143 lpp. (in Latvian) Dobrowolska, D., Hein, S., Oosterbaan, A., Wagner, S., Clark, J., Skovsgaard, J. P. (2011). A review of European ash ( Fraxinus excelsior L.): Implications for silviculture. Forestry , 84 (2

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The Effect of Altitude on the Pattern of Gene Flow in the Endemic Canary Island Pine, Pinus canariensis

Service, Rocky Mountain Research Station, Fort Collins. LATTA, R. G. and J. B. MITTON (1997): A comparison of population differentiation across four classes of gene marker in limber pine (Pinus flexilis James). Genetics 146: 1153-1163. LEDIG, F. T. (1998): Genetic variation in Pinus, pp. 251-280. In: Ecology and Biogeography of Pinus, edited by D. M. RICHARDSON. Cambridge University Press, Cambridge. LEGENDRE, P. and L. LEGENDRE (1998): Numerical Ecology. Elsevier, New York. MANTEL, N. A. (1967): The

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I-SSR Markers Revealed Inconsistent Phylogeographic Patterns among Populations of Japanese Red Pines in Korea

Abstract

To monitor the level and distribution pattern of genetic diversity in countrywide populations of Japanese red pines in Korea, 80 I-SSR variants were analyzed from 192 individuals in 11 populations. The previously reported data, obtained from the 8 populations of this species, were incorporated into the estimation of the population genetic statistics. Relatively higher level of genetic diversity was observed in 19 populations of Japanese red pines (mean of 0.453) than those in other tree species. From the results of AMOVA, majority of genetic diversity (92%) was allocated within populations, which brought about the moderate degree of population differentiation (ϕST= 0.08). Two genetic groups were observed from the dendrogram reconstructed by UPGMA. Overall correlation between genetic relationships and geographic affinity was inconsistent among the 19 populations. Some probable genetic disturbances, induced by either human interference or the natural process of regeneration for the species after devastation, might be responsible for the discrepancy between genetic relationships and geographical distribution of the populations. These results suggested that simple geographic or ecological grouping might not represent the genetic zone of the Korean populations of Japanese red pines, and that more careful approach should be made for designating in situ gene conservation of this species in Korea.

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Discordance Between Geographical Distribution and Genetic Relationship Among Populations of Japanese Red Pine in Korea Revealed by Analysis of I-SSR Markers

Abstract

Level and distribution of genetic diversity in 8 populations of Japanese red pine in Korea were estimated using I-SSR variants. A total of 80 I-SSR variants were observed in the analyzed 150 individuals, which revealed DNA fingerprints-like individual specific amplicon profiles for all of them. Relatively higher level of genetic diversity within populations was observed in 8 populations of Japanese red pine (mean of 0.450) than in other tree species. From the results of AMOVA, majority of genetic diversity was allocated within populations (93.42%) resulting in a moderate degree of population differentiation (ΦST= 0.066). The observed distribution pattern of I-SSR variants among 8 populations was coincided with the typical patterns for the long-lived woody species. Genetic relationships among the populations, reconstructed by UPGMA and Neighbor- Joining methods, revealed 2 genetic groups. The populations of Gangwon-Uljin and Chungnam-Taean turned out to be the most closely related despite a distant location between them. The overall genetic relationships among the 8 populations, reconstructed by both methods, were not coincided with geographic distances. The discrepancy between genetic relationships and geographical distribution among the populations suggests that the analyzed populations might have undergone random changes in genetic composition due to some kinds of disturbances. Results obtained in this study suggests that more careful approach should be made in preparing strategy for gene conservation of Japanese red pine in Korea. More information on countrywide molecular population genetic status of Japanese red pine will be helpful to prepare more reasonable strategy for gene conservation of the species in the country.

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Problems in the Analysis of Genetic Differentiation Among Populations – a Case Study in Quercus robur

. VAN DAM, A. DUCOUSSO, I. FORREST, U. L. DE HEREDIA, A. J. LOWE, M. TUTKOVA, R. C. MUNRO, C. STEINHOFF and V. BADEAU (2002): Leaf morphological differentiation between Quercus robur and Quercus petraea is stable across western European mixed oak stands. Annals of Forest Science 59: 777-787. LATTA, R. G. and J. B. MITTON (1997): A comparison of population differentiation across four classes of gene marker in Limber Pine (Pinus flexilis James). Genetics 146: 1153-1163. MANLY, B. F. J. (1997): Randomization, Bootstrap and Monte Carlo

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Genetic Variability and Structure of The Wild Service Tree (Sorbus torminalis (L.) Crantz) in Poland

Abstract

Sorbus torminalis is a rare forest tree species in Poland. Allelic and genotypic structures at 25 isozyme gene loci were observed in 20 populations from Poland, situated mainly along a latitudinal gradient. Levels of genetic diversity were high both at the species level (P = 44%, He = 0.435) and within populations (mean P = 40.8%, mean He = 0.373). Levels of differentiation among populations were relatively high (FST = 0.17) and a noticeable geographic structure of this differentiation was detected. The population in the ‘Brekinia’ reserve had a unique genetic structure of a clonal population and was the most distinct from the other populations.

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Allozyme Variation in Different Species of Deciduous Oaks From Northwestern Italy

Abstract

Allozyme variation was studied by electrophoresis at 11 loci in 14 populations of Quercus petraea, Q. robur, Q. cerris and Q. pubescens from Piedmont, northwestern Italy. The aim of the work was to characterize the genetic resources and to suggest effective measures for in situ preservation of biodiversity. As expected, most of the genetic variability was found at the within population level, and genetic differentiation accounted for about 14% of it. The study confirmed the low level of genetic variability among the species studied: only Q. cerris populations could be clearly distinguished. Q. pubescens could be separated from Q. petraea and Q. robur using Principal Coordinate Analysys. The latter was also found to be useful for separating Q. petraea and Q. robur populations. However, in mixed populations, the differentiation between the latter species was similar to that scored among populations belonging to the same species. A significant deviation from random mating was observed, although it was variable among species: Q. pubescens had the highest value for the inbreeding coefficient FIS (0.159).

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Population Differentiation and Climatic Adaptation for Growth Potential of White Spruce (Picea glauca) in Alberta, Canada

Abstract

Genetic differentiation among white spruce populations in Alberta, Canada, was studied using time series data of height and diameter and a climatic index developed by principal component analysis. The objectives were to discern patterns of variation for growth potential and predicted optimum climate; compare optimum climate between populations, between height and diameter at the same age and between height or diameter at different ages; and to see if optimum climate differed from the climate inhabited by populations. Using cluster analysis we found that: (1) populations from mid-latitudes (54° - 57°N) and mid-elevations (600 - 800 m) were grouped together and exhibited high growth potential; populations from north of 57°N were grouped with those from elevations higher than 900m in the Rocky Mountains and exhibited low growth potential; and (2) With minor exceptions, populations from similar climates or geography were grouped together in terms of predicted optimum climate. (3) Analysis of variance showed that optimum climate differed significantly (P < 0.05) among populations; among heights at different ages; among diameters at different ages and between height and diameter at the same ages. However, there was no consistent trend in the direction of change in optimum climate with tree age. (4) The range of climate inhabited by the populations (PI₁ = -5.792 to 4.483) was much wider than the range of their predicted optimum climate (P̂Ō₁ = -1.001 to 0.842), which suggests that in terms of growth potential some populations inhabit sub-optimal climates. Implications of the results on management of white spruce in Alberta are discussed.

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