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84%
Sylwan
|
1998
|
tom 142
|
nr 12
23-31
The plant material was collected on 34 individuals growing in the Dendrological Garden of Poznań University of Life Sciences (52°25'32,95" N 16°53'39,83" E) and Botanical Garden of Adam Mickiewicz University in Poznań (52°25'11,70" N 16°52'55,07" E). The species for this study originated from Europe, Asia Minor, central and eastern Asia and North America and included: Abies alba, Abies cephalonica, Abies cilicica, Abies equi−trojani, Abies sibirica, Abies koreana, Abies pinsapo, Abies ×insignis, Abies bornmulleriana, Abies homolepsis, Abies holophylla, Abies grandis, Abies concolor, Abies concolor var. violacea, Abies concolor var. lowiana, Abies nordmanniana, Abies ×arnoldiana, Abies nephrolepis and Abies balsamea. The aim of this study was to define the species haplotypes (the length of allele) on the basis of nad5−4 mitochondrial DNA marker detected by capillary electrophoresis. This marker has been suggested as an easy−to−use tool to distinguish species of the Abies genus and it could be species−specific. Seven different haplotypes were identified. The first one appears in the species from Europe, Asia and North America. The second one was detected in firs from Europe and Asia Minor. A. cephalonica and A. sibirica were identified by the third haplotype, which occurs also in A. alba from the Balkan region. The fourth haplotype is characteristic for species from Asia and North America. The fifth and sixth haplotypes were identified in A. pinsapo and A. numidica. The seventh haplotype was detected only in A. holophylla. Applied marker is a very useful for verification of fir species especially allopatric species, less for parapatric ones. This marker is more helpful to exclude the species than to precisely identify them.
6
84%
This paper provides results of somatic embryogenesis study in our laboratory. General description of somatic embryogenesis (SE) induction, maturation of somatic embryos and plantlets regeneration of the Abies species, followed by a comparisons of some characteristics of zygotic and somatic embryos, seedlings and emblings (somatic seedlings). Own results are supplemented with some literature data. Also aplication of SE for improving of plantlet regeneration of elite fir trees from Dobroč primeval is described as well as initiation of the SE from seeds of incompatible crossings of firs where zygotic embryos abort usually several weeks after pollination
To determine the optimum plot size for bryophyte-biocoenosis investigations and identify the sampling methods that can provide sufficient and representative data for bryophyte diversity, we explored two sampling methods and investigated the species composition and their coverage in three sites located within the subtropical- temperate zone in China: mixed coniferous and deciduous broadleaved forest with species of Quercus, Betula, Pinus, Abies (Guanyinshan Nature Reserve), mixed evergreen and deciduous broadleaved forest, broadleaved forest with species of Phoebe, Castanopsis, Lithocarpus, Acer, Tilia, Dacidia, Abies (Mabian Dafengding Nature Reserve) and temperate deciduous broadleaved forest with species of Quercus, Betula, Populus (Dongling Mountains). Two sampling methods are applied: the systematic-sampling method based on nested quadrates of five different sizes (10 × 10 cm, 25 × 25 cm, 50 × 50 cm, 1 × 1 m, and 2 × 2 m) in each 2 × 2 m grid within a 10 × 10 m plot (total 25 grids) and the microcoenose-sampling method (sampling with the minimum area quadrate at the center of the largest fragment in each of the 25 grids). The minimum area of sampling was determined based on the similarity-area curve, the coverage-area curve, and the importance- value-area curve through the systematicsampling. The appropriate sampling method and quadrate number were determined by analyzing the species diversity and evenness. We compared two sampling methods by assessing the species number at two different sites. Both the similarity- area curve and importance-value-area curve showed that the turnover point of sampling size occurred at 50 × 50 cm where the similarity and importance-value were closer to the actual. We concluded that a quadrate of 50 × 50 cm could be used as the minimum area of sampling. However, the systematic-sampling method was not suitable for analyzing the diversity of bryophytes. A viable alternative is the microcoenose-sampling method which allows to obtain sufficient information in terms of species richness and their distribution.
Aura
|
1995
|
nr 02
15-16
Water management, understood as a complex of interactions and circulation of water in the environment, is vital to protection of the fir in the Bieszczady Mountains. Disturbances in water management during the last ten or fifteen years have exceeded the ability of the fir to adapt to drought stress. The fir, a species with strict climatic requirements, grows on a mosaic of diversified soils and subsoil, and is strongly affected by any change in them. Specimens growing on less favourable sites are subject to diseases, including those caused by climatic irregularities. The author puts forward proposals for shaping environmental conditions for fir protection.
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