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1.
Genetika ; 50(3): 291-8, 2014 Mar.
Artículo en Ruso | MEDLINE | ID: mdl-25438549

RESUMEN

Two mitochondrial DNA fragments, nad4(3c-4r) and nad5(1-2r), were sequenced in 58 larch accessions from the range of Larix olgensis A. Henry. Combinations of the nad4 polymorphic sites formed four haplotypes, two of which (H3 and H4) were unique and two (H1, H2) were common. Haplotype H1 was found only in pure L. olgensis from the vicinity of Olga Bay and in a number of accessions from the southern part of the range. Haplotype H2 was detected in the other samples from the range of Olga Bay larch, as well as in hybrid forms. Similarly to the nad4(3c-4r) fragment, the mtDNA fragment UBC460 was able to differentiate larch populations from the range of L. olgensis examined.


Asunto(s)
ADN Mitocondrial/genética , ADN de Plantas/genética , Larix/genética , Polimorfismo Genético , Ecosistema , Haplotipos , Siberia
2.
Genetika ; 48(3): 340-51, 2012 Mar.
Artículo en Ruso | MEDLINE | ID: mdl-22679781

RESUMEN

Genetic variability in ten populations of wild-growing ginseng was assessed using AFLP markers with the application of fragment analysis on a genetic analyzer. The variation indices were high in the populations (P = 55.68%; H(S) = 0.1891) and for the species (P = 99.65%; H(S) = 0.2857). Considerable and statistically significant population differentiation was demonstrated (theta = 0.363; Bayesian approach, "full model"; F(ST) = 0.36, AMOVA). The results of AMOVA and Bayesian analysis indicate that 64.46% of variability is found within the populations. Mantel test showed no correlation between the genetic and geographic distances among the populations (r = -0.174; P = 0.817). Hierarchical AMOVA and analysis of genetic relationships based on Euclidean distances (NJ, PCoA, and MST) identified two divergent population groups of ginseng. Low gene flow between these groups (N(m) = 0.4) suggests their demographic independence. In accordance to the concept of evolutionary significant units (ESU), these population groups, in terms of the strategy and tactics for conservation and management of natural resources, should be treated as management units (MUs). The MS tree topology suggests recolonization of southern Sikhote-Alin by ginseng along two directions, from south and west.


Asunto(s)
Análisis del Polimorfismo de Longitud de Fragmentos Amplificados/métodos , Variación Genética , Panax/genética , Genética de Población , Filogeografía , Federación de Rusia
4.
Genetika ; 46(8): 1057-66, 2010 Aug.
Artículo en Ruso | MEDLINE | ID: mdl-20873202

RESUMEN

The genus Panax (Araliaceae) is world-famous because many its members have important medicinal properties. Panax ginseng C. A. Meyer is more popular than other species of the genus because remedies prepared from this plant stimulate immunity, help to prevent diseases, and have antistress effects. In addition, the ginseng root extract is traditionally used as a means against aging. At present, this species is found in the wild only in Primorsky krai, Russia, but its populations are extremely exhausted and need to be restored. In this study, effectiveness of molecular DNA markers in detecting genetic variation and differentiation of the ginseng populations was tested. Genetic variation of ginseng, identified using RAPD (P = 4%; H(pop) = 0.0130) and ISSR (P = 9.3%; H(pop) = 0.0139) markers was low. The AFLP* approach, according to which amplicons are separated in polyacrylamide gel and visualized by means of silver staining, showed somewhat higher variability (P = 21.8%; H(pop) = 0.0509), while its effectiveness in population differentiation was as low as that of RAPD and ISSR. The AFLP** technique, which included analysis of the fragments using genetic analyzer, revealed high genetic differentiation of ginseng (P = 94.4%; H(pop) = 0.3246). All populations examined using the AFLP** markers were statistically significantly differentiated based on the AMOVA results. Our result suggest effectiveness of AFLP** markers for characterization of the genetic structure and genetic relationships of the ginseng populations. These markers are recommended for use in large-scale population genetic studies of this species to develop measures of its conservation.


Asunto(s)
Genes de Plantas , Marcadores Genéticos , Panax/genética , Análisis del Polimorfismo de Longitud de Fragmentos Amplificados , Asia Oriental , Variación Genética , Técnica del ADN Polimorfo Amplificado Aleatorio , Federación de Rusia
6.
Izv Akad Nauk Ser Biol ; (6): 670-5, 2010.
Artículo en Ruso | MEDLINE | ID: mdl-21268865

RESUMEN

Karyological study of larch population members from different parts of the Larix olgensis L. Henry areal in the Primorskii krai has been carried out. The main amount of chromosomes for larch as n = 12 (2n = 24) has been confirmed. Mixoploidy was observed in all studied populations. The difference of individuals from the larch areal based on the cell amount with a different level of ploidity has been found in the population of L. olgensis locus classicus and both L. sibirica and L. gmelinii, which is probably a consequence of their hybrid nature.


Asunto(s)
Quimera/genética , Cromosomas de las Plantas/genética , Sitios Genéticos/genética , Larix/genética , Mosaicismo , Ploidias , Genética de Población , Siberia
7.
Genetika ; 44(3): 374-80, 2008 Mar.
Artículo en Ruso | MEDLINE | ID: mdl-18664142

RESUMEN

The level of within- and among-population variation of larch inhabiting the range of Larix olgensis A. Henry in Primorye was estimated on the basis of 440 RAPD loci identified by means of 12 random primers. In ten population examined, the proportion of polymorphic loci was 35-60%, the average expected heterozygosity varied from 0.1340 to 2169, and the average gene flow estimate was 1.38. According to Fisher's test for heterogeneity, the pairwise differences of the fragment frequencies between the populations were statistically significant. The subdivision index G(ST) = 0.2663 indicated that the interpopulation variation component accounted for approximately 27% of the total variation. Coefficients of Nei's genetic distance between the populations varied from 0.0137 to 0.0934. Most of the samples with high support clustered according to the geographic positions relative to one another within the range. These results suggest that the populations examined are characterized by high genetic variation, like the larch populations of Siberia and the Russian Far East studied earlier, but, in contrast to the latter, exhibit higher among-population variability.


Asunto(s)
Variación Genética , Larix/genética , Asia Oriental , Genética de Población , Heterocigoto , Siberia
10.
Genetika ; 41(6): 800-10, 2005 Jun.
Artículo en Ruso | MEDLINE | ID: mdl-16080605

RESUMEN

In eight species of the family Araliaceae, inhabiting the territory of the Russian Far East, the sequences of ITS regions of nuclear rDNA were determined. A comparison of these sequences enabled establishment of phylogenetic relationships between the Far Eastern and other members of the family. It was demonstrated that Aralia sensu populations from Primorye and Sakhalin were genetically different and, hereby, could be classified as interspecific taxa. Aralia continentalis along with A. cordata were attributed to the section Aralia sensu. Oplopanax elaus and O. horridus were found to be very close to each other, possibly being the subspecies of one species or relatively young species. Legitimacy of the isolation of two sections within the genus Eleutherococcus was confirmed.


Asunto(s)
Araliaceae/genética , ADN de Plantas/genética , ADN Ribosómico/genética , Filogenia , Araliaceae/clasificación , Siberia
11.
Genetika ; 40(4): 506-15, 2004 Apr.
Artículo en Ruso | MEDLINE | ID: mdl-15174284

RESUMEN

Genetic diversity of larches from six geographically isolated regions, Tomsk, Irkutsk, Ulan-Ude (Siberia), and Blagoveshchensk, Khabarovsk, Yuzhno-Sakhalinsk (Far East) was examined by means of RAPD analysis. Tree DNA samples were compared using 457 RAPD loci (97% of which were polymorphic), identified with 17 primers of random sequences. In the samples examined, 32 to 49% of the genes were in heterozygous state, mean expected heterozygosity (Hexp) varied from 0.1373 to 0.1891, and the genetic distances (DN) for different sample pairs varied from 0.0361 to 0.1802. The main population parameters were determined for Larix sibirica Ledeb., L. gmelinni (Rupr.) Rupr., and L. kamtschatica (Rupr.) Carr. Analysis of the genetic relationships showed that L. kamtschatica was characterized by highest genetic differentiation from the other larches examined, while larches from Primorskii krai were genetically close to L. sibirica.


Asunto(s)
Larix/genética , ADN de Plantas , Heterocigoto , Larix/clasificación , Reacción en Cadena de la Polimerasa , Técnica del ADN Polimorfo Amplificado Aleatorio , Siberia , Especificidad de la Especie
12.
Genetika ; 40(2): 239-47, 2004 Feb.
Artículo en Ruso | MEDLINE | ID: mdl-15065432

RESUMEN

Inter- and intraspecific variation of two ginseng species Panax ginseng and P. quinquefolius was estimated by studying 159 RAPD and 39 allozyme loci. Parameters of polymorphism and genetic diversity were determined and a tree was constructed to characterize the differences between individual plants, samples, and species. Genetic variation in P. ginseng proved to be lower than in P. quinquefolius. Gene diversity in the total P. ginseng sample was comparable with the mean expected heterozygosity of herbaceous plants. This suggests that wild P. ginseng plants in various areas of the currently fragmented natural habitat and cultivated plants of different origin have retained a significant proportion of their gene pool. The mean heterozygosity calculated per polymorphic locus for the RAPD phenotypes is similar to that of the allozyme loci and may be helpful in estimating gene diversity in populations of rare and endangered plant species.


Asunto(s)
Enzimas/genética , Variación Genética , Panax/genética , Heterocigoto , Panax/enzimología , Técnica del ADN Polimorfo Amplificado Aleatorio , Especificidad de la Especie
13.
Genetika ; 39(1): 57-63, 2003 Jan.
Artículo en Ruso | MEDLINE | ID: mdl-12624934

RESUMEN

A molecular genetic study of Far Eastern species of the family Araliaceae by means of RAPD analysis was conducted. Using 21 primers we assessed variability at 595 loci. Based on matrices of genetic distances D, dendrograms of genetic relationships among eleven species of six genera of this family were constructed. Our results suggest that Acanthopanax sessiliflorus and Eleutherococcus senticosus belong to different genera, Aralia cordata and A. continentalis are different species, and A. elata and A. mandshurica probably cannot be regarded as distinct species. Genetic similarity of Far Eastern A. cordata and American A. hispida is shown.


Asunto(s)
Araliaceae/genética , Filogenia , Técnica del ADN Polimorfo Amplificado Aleatorio , Araliaceae/clasificación , ADN de Plantas/química , Asia Oriental , Variación Genética
14.
Izv Akad Nauk Ser Biol ; (2): 243-8, 2001.
Artículo en Ruso | MEDLINE | ID: mdl-11357392

RESUMEN

We studied applicability of RAPD assay for investigating genetic variability of far eastern larches. Techniques to isolate DNA from larch vegetative organs (needles, young shoots and stems) and megagametophytes were selected, and conditions of polymerase chain reaction were optimized. Fifty out of 84 random primers proved efficient, and 22 and 12 primers initiated weak and no synthesis, respectively. The tested primers worked efficiently on the DNA isolated from both diploid and haploid tissues.


Asunto(s)
ADN de Plantas/análisis , Estructuras de las Plantas/química , Árboles/química , Asia Oriental , Técnica del ADN Polimorfo Amplificado Aleatorio , Siberia
15.
Mol Biol (Mosk) ; 35(1): 152-6, 2001.
Artículo en Ruso | MEDLINE | ID: mdl-11234375

RESUMEN

Genetic variability of Iris setosa Pall. ex Link. was studied by the RAPD method. Plants from three different habitats were compared by 135 loci revealed with eight arbitrary primers. The three plant accessions all exhibited a high level of polymorphism, and each was characterized by different frequencies of polymorphic fragments, which probably reflected the geographic isolation of the analyzed populations. The average level of polymorphism detected was 35%.


Asunto(s)
Variación Genética , Magnoliopsida/genética , Filogenia , Polimorfismo Genético , Técnica del ADN Polimorfo Amplificado Aleatorio
18.
Virology ; 163(1): 198-200, 1988 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-3347998

RESUMEN

The effect on Tobacco mosaic virus (TMV) accumulation of actinomycin D (AMD) introduced shortly after inoculation into isolated tobacco protoplasts under varying light conditions was examined. The emission spectrum of the light source contained lines in the visible range and in the ultraviolet band (300-400 nm). AMD absorbed light in the visible (400-500 nm) and in the uv (200-400 nm) ranges. AMD substantially inhibited TMV multiplication in the light, and also when the protoplasts were incubated in petri dishes covered with a black filter that allowed only uv light in the range 260-390 nm to pass. In the dark, and also in petri dishes covered with blue or yellow filters that passed in the ranges 400-500 or 500-600 nm, respectively, AMD stimulated TMV reproduction. The suppression of TMV multiplication in isolated tobacco protoplasts was assumed to be associated with a photodynamic effect caused by absorption of uv light by AMD.


Asunto(s)
Dactinomicina/farmacología , Luz , Virus del Mosaico del Tabaco/efectos de los fármacos , Dactinomicina/efectos de la radiación , Oscuridad , Plantas Tóxicas , Protoplastos/microbiología , Nicotiana/microbiología , Virus del Mosaico del Tabaco/crecimiento & desarrollo , Rayos Ultravioleta
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