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With the help of 21 putative isoenzyme loci, the genetic diversity and variations of Viscum album ssp. album L. from 42 species, subspecies, varieties and hybrids of broadleaf trees, Viscum album ssp. austriacum (Wiesb.) Vollmann, from 4 populations of Scots pine (Pinus sylvestris L.) and Viscum album ssp. abietis (Wiesb.) Abromeit, from 8 populations of European silver fir (Abies alba Mill.) were analyzed. On the dendrogram, the three investigated subspecies form three clusters, each clearly separated from the other, so we suggest a revision of the systematic nomenclature proposed to take into consideration a return to an earlier system of dividing the European mistletoe into three species: Viscum album L., Viscum abietis Beck, and Viscum laxum Boiss. et Reut. From among the 21 tested loci only one locus, SOD-A, was monomorphic. The average number of actual alleles (Na) and effective alleles (Ne) was 2.23 and 1.61 respectively. The observed heterozygosity (Ho) varied from 0.199 in V. album ssp. abietis to 0.345 in the V.a. ssp. album populations. Average FST = 0.277 indicates that about 28% of genetic differentiation is due to an interpopulation diversity of Viscum album populations. There is a small gene flux between Viscum album populations with only one immigrant successfully entering a population per two generations (Nm = 0,653).
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Rozmnażanie wegetatywne daglezji zielonej

100%
Sylwan
|
1996
|
tom 140
|
nr 02
25-37
11
100%
Twenty-eight isozymic loci were studied in the Beskid Mts., in four populations of common silver-fir (Abies alba): 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 (I = 0.42), percentage of polymorphic loci (%PoL = 64.29) and number of rare alleles (NoRa = 5). Besides, the BM population has the highest observed heterozygosity (Ho = 0.291), which exceeds the expected heterozygosity (He = 0.254), 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 He = 0.262 and Ho = 0.264.
To assess the inter- and intrapopulation genetic variation in the filial generation (F1) of alder (Alnus glutinosa (L.) Gaertn.), 11 naturally regenerated populations were analysed. Their parental populations (P), represent the whole Polish territory and belong to three phytosociological associations with alder: typical alder swamp forest Carici elongatae-Alnetum (Ce-A); alder riparian forest Circaeo-Alnetum (C-A); and ash-elm riparian forest Fraxino-Ulmetum (F-U). F1 populations are grown in a common-garden experiment (provenance trial). Genotyping of individual trees has been carried out by analysis in a bud tissue allele frequency in the 21 isozyme putative loci of 10 enzymes. Differences between populations in respect to the level of genetic diversity were not high. Genetic diversity measured as the number of effective alleles per locus was the highest (Ne = 1.65) in population Wińsko originating from F-U (where also the inbreeding coefficient was the highest, F = 0.429), and the lowest (Ne = 1.48) in population Sławki from Ce-A. In all investigated populations, observed heterozygosity (Ho = 20%) was lower than expected from H-W equilibrium (He = 29%). The highest genetic variation expressed as percentage of polymorphic loci (77.3%) was observed in the offspring populations from Ce-A, and the smallest (69.9%) in the populations originating from F-U. It seems that the low genetic differentiation between populations is probably connected with long-distance seed dispersal via river systems. Alder seed can be transported over long distances thanks to periodical flooding. There is some gene flow between alder populations, with about 2.5 immigrants successfully entering a population per generation (Nm = 2.55). The level of population subdivision within A. glutinosa was low (Fst = 0.089). There was no significant genetic differentiation between populations from different phytosociological associations. Mantel test exhibited no significant correlation (r = 0.077) between genetic and geographic distance. In the dendrogram constructed according to Nei (1972) on the basis of interpopulation genetic distances, many small groups can be observed.
Seeds collected from individual trees in the 16 Carpathian and 2 Sudeten silver-fir (Abies alba) populations were studied with the starch gel electrophoresis in megagametophytes using 14 enzyme systems with 28 loci. The results show that the geographical distance between populations are in a small part reflected in genetic distances. There are two main groups of populations: Sudeten and Carpathian with a very big genetic distance between them. Other populations consist of a few small groups with low gene flow between them (Nm = 3.286). About 80% of genetic variation is located within populations (FST = 0.223). Average values for genetic multiplicity and diversity for Carpathian populations are as follows: number of alleles per locus: Na = 2.308, with effective number of alleles Ne = 1.552 and proportion of polymorphic loci 71.21%. The mean number of alleles per locus (Na) varied from 2.107 to 2.607 in population. The mean effective number of alleles per locus (Ne) ranged from 1.429 to 1.662. Average Fis for Carpathian populations was -0.021, which means that there is small excess of heterozygotes. The average observed heterozygosity amounted to Ho = 0.275 and expected heterozygosity was He = 0.269. The dendrogram structure and presence of rare alleles found in silver-fir of Czech, and Slovakian populations allow for a hypothesis that in postglaciation the silver-fir moved into the Polish Carpathians not westward from the east but from the south along river valleys from some Balkan refuges, getting North bypassing the High Tatra Range. This way, a highly diversified set of populations originated, differ in the presence of rare alleles. This differentiation is not prevented by a relatively small flow of genes between populations. The calculated gene flow Nm = 3.286 also indicates isolation between the populations. It means 3.3 immigrants per generation into the studied populations.
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