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Possibilities for using molecular markers to improve genebank efficiency are increasingly present thanks to developments in genebanks and developments in molecular genetics. These possibilities relate to all aspects of genebank management: acquisition, maintenance, characterisation and utilisation. However, two pitfalls should be avoided. The first lies in the neutrality of the most generally used markers, making them less suitable for optimising genetic diversity. The second is related to the considerable costs involved in using molecular markers. In many cases an economical analysis will have to decide if the markers can routinely be used in genebank operations. Some examples of model studies and applications of molecular markers in genebank operations will be presented, in which both genetic and economic aspects will be illustrated briefly. These examples involved existing genebank collections of wild lettuce, cabbage and wild potato.
W pracy określono zmienność cech użytkowych odmian jęczmienia ozimego zgromadzonych w Banku Genów. W tym celu wykonano następujące obserwacje i pomiary: przezimowanie roślin, odporność na podstawowe choroby i wyleganie, wysokość roślin, długość i waga kłosa, liczba ziaren w kłosie, masa 1000 ziaren oraz odporność częściowa na mączniaka prawdziwego. Testowane odmiany znacznie różniły się pod względem badanych cech. Pozwoli to na wyodrębnienie genotypów jęczmienia ozimego o pożądanych cechach agronomicznych i włączenie ich do programów hodowlanych.
Zasoby genowe są przechowywane w postaci roślin in vitro w warunkach spowolnionego wzrostu. Metoda ta polega na zapewnieniu tkance roślinnej minimalnych warunków do wzrostu, tak aby maksymalnie ograniczyć jej starzenie się. Stosuje się pożywki o określonym składzie, obniża temperaturę hodowli do 6-10oC i zmniejsza intensywność światła do ok. 4-6 W/m2. Dodanie do pożywki Murashige- -Skooga (MS) inhibitorów wzrostu, np. kwasu abscysynowego (ABA) albo związków o charakterze osmoticum, np. D-Mannit, wydłuża czas przechowywania zasobów nawet do 5-6 lat bez konieczności przeszczepiania na świeżą pożywkę (ok. 30% zasobów).
The paper summarises the results of climatological studies concerning the area of the Carpathian Regional Gene Bank station located in the Wisła Forest District. The work provides raw meteorological data, daily, monthly, seasonal and annual records, and various indices such as the pluvial-thermal index, biometeorological index, Sielianinow’s index and de Martonne’s index. In addition, the detailed profiles of thermal, humidity and rainfall conditions are presented against a background of the general synoptic situation.
The aim of these studies was to analyse the genetic changes induced by natural aging during long-term seed storage of rye. For this purpose, the AFLP (Amplified Fragment Length Polymorphism) technique was applied. In the experiment, DNA variation was demonstrated in seven-day-old seedlings of four seed samples of cv. Dankowskie Zlote, showing different levels of viability following long-term storage. Among the 362 AFLP fragments analysed, 73 had significantly different frequencies in at least one of the series. Principle Coordinate Analysis (PCA) based on molecular data revealed differences between the progenies of naturally aged seed samples with variable initial viability. It was clearly shown that materials with low viability differed in structure from highly viable ones, and that the population changes exhibited in the first case are preserved through regenerations. Although changes that were observed for initially viable samples were not so significant, they still occurred - probably as a result of genetic shift.
Modern forest selection programs concern natural and protected populations of trees characterized by a great genetic variability and also production stands frequently deformed by human activity. In the latter, artificial regeneration is prevailing. Forest nurseries working in the organizational structures of State Forests can guarantee the proper provenance (genotype)of seeds and the quality of seedlings obtained from them. The condition, however, is a close uniformity in the conservation of forest gene resources, and selection breeding of forest trees. The success of the program depends also on the development of modern infrastructure for forest nurseries and applied technologies. The latter task was the field of activity of Professor Bolesław Suszka, Ph.D., and his many-year research and organizational and didactic activity in Poland and abroad. The methods in long-term storage and their pretreatment in case of dormant seeds, developed by Professor Suszka, created the theoretical and practical basis for the conservation of forest gene resources not only in Poland.
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Experiments had been carried out on gametophytes and very young fronds of sporophytes with application of Murashige and Skoog (1962) medium. The paper described the results of 15 years in vitro experiments on 16 species of tree ferns belonging to various genera: Blechnum, Cibotium, Cyathea and Dicksonia. Genus Cyathea was represented by: C. australis (R.Br.) Domin., C. capensis (L.f.) Sm., C. cooperi (F.Muell.) Domin, C. brownii Domin, C. dealbata (G.Forest) Sw., C. dregei Kunze, C. leichhardtiana (F.Muell.) Copel., C. robertsiana (F.Muell.) Domin., C. schanschin Mart., C. smithii Hook.f. and Cyathea sp. In case of genus Dicksonia only two species were introduced into our experiments: D. fibrosa Colenso and D. sellowiana Hook.. Taxa Blechnum was presented by B. brasiliense Desv. and Cibotium by C. glaucum (Sm.) Hook. and Arn. and C. schiedei Schltdl. and Cham.. The studied species presented various responses on culture conditions depending on the level of stage of development. Time required for spores germination differed between species and took from only a few to 16 weeks. Prothalium formations showed various types of growth presented by marginal meristems. For all investigated species long term gametophyte in vitro cultures was established. Mature gametophyte possessed functional antheridia and archegonia. Spontaneous fertilization helped to establish the culture of young sporophytes. For all species the ex vitro culture in greenhouse collection was established. Manipulation of sucrose content in the medium stimulated the multiplication of gametophytes, but its lack induced formation of gemmae. Apospory was observed when culture of very young fronds was extended for 6 months and new generation of gametophytes was developed. Finally, sporophytes of 12 species were obtained and they have been growing in our greenhouse.
The work outlines the directions in the past and present research into the variability of Norway spruce in Poland, and presents the results of provenance experiments concerning the genetic and breeding value of provenances tested in the Polish range of spruce distribution. The Istebna race proved to have a good value, however, so far only the progeny of single stands have been tested. It is thus necessary to determine the range of distribution for this race. The altitude of the location of mother stands significantly correlates with the genetic and breeding value of their progeny cultivated at different altitudes. This suggests that the altitude and exposure of plantations to be established in mountain forest belts should be specified for individual provenances (altitudinal zoning). New inventory provenance tests should be run under varied site conditions to assess both the genetic value and plasticity range of the provenances. In view of the biotic and abiotic threats facing spruce, there is a need to work out detailed programmes designed to preserve its genetic resources in gene banks and in vivo archives.
Kriokonserwacja jest to metoda przechowywania zamrożonego materiału biologicznego w bardzo niskich temperaturach, najczęściej w ciekłym azocie (-196° C). W pracy dokonano przeglądu literatury na temat kriokonserwacji materiału roślinnego pochodzącego z kultur in vitro, z uwzględnieniem metod, warunków procesu i możliwości szerokiego zastosowania w bankach genów. Zestawiono wyniki uzyskane przez autorów zajmujących się kriokonserwacją różnych gatunków roślin.
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