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PL
Z heterozyjnych mieszańców jęczmienia za pomocą kultur pylnikowych wyprowadzono linie podwojonych haploidów, które porównano z mieszańcami pod względem cech agrobotanicznych. W trzech z czterech badanych kombinacji krzyżówkowych wyselekcjonowano z częstością 4,4-18% linie DH, które pod względem plonowania dorównywały mieszańcom heterozyjnym. Wykazano, że przyczyną wystąpienia efektu heterozji u badanych mieszańców było dominowanie oraz addytywne i nieaddytywne współdziałanie genów z różnych loci.
EN
Doubled haploids DH were obtained from 4 heterosis crosses of the barley by another cultures. Agronomic performance of DH lines and hybrids was compared. In 3 crosses (the crosses between mutants from the same variety or between a mutant and parent variety) the heterosis hybrids performing DH lines were selected. These DH lines proved that the mechanism underlying heterosis in F₁ was the dominance, as well as the additive and nonadditive interaction between genes from different loci.
PL
Człowiek od tysięcy lat modyfikował gatunki roślin i zwierząt dostosowując je do swoich potrzeb. Tradycyjne techniki hodowli takie jak mutageneza czy introgresja prowadzą niejednokrotnie do znacznych zmian w genomie obejmujących wiele genów. Główną zaletą inżynierii genetycznej jest możliwość przenoszenia pojedynczych genów bez modyfikacji pozostałej części genomu. Dlatego jest to metoda wspomagająca hodowlę tradycyjną, która pozwala wzbogacać najlepsze genotypy w pożądane cechy. Mikroorganizmy transgeniczne są powszechnie wykorzystywane do produkcji leków i dodatków spożywczych, wśród roślin najczęściej uprawia się odmiany odporne na herbicydy, choroby i szkodniki, natomiast zwierzęta transgeniczne są w przededniu wprowadzenia na rynek. Wykorzystanie GMO stwarza możliwość przezwyciężenia wielu problemów związanych z produkcją żywności, poprawą jej jakości oraz zapobieganiem chorobom. Wprowadzenie GMO wiąże się jednak z zagrożeniami dotyczącymi bezpieczeństwa żywności i wpływu na środowisko. Zwraca się uwagę także na zagrożenia ekonomiczne. W celu zapobieżenia ujemnym skutkom komercjalizacji GMO w większości państw rozwiniętych, w tym w Unii Europejskiej wprowadzono regulacje określające zasady oceny żywności transgenicznej przed wprowadzeniem na rynek oraz zasady uwalniania GMO do środowiska.
EN
Plants and animals have been modified for thousands years in order to adapt them to human needs. Traditional breeding methods such mutagenesis and introgression frequently lead to multiple changes in the genome that cover many genes. The main advantage of genetic engineering is the ability to manipulate with a single gene without modification of the rest part of genome. Therefore this is the technology that supplements the traditional breeding at the end to add the specific characters to the best, previously selected genotypes. Transgenic microorganisms are commonly used to production of drugs and food compounds, the most transgenic plants are resistant to herbicides, diseases and pests, the transgenic animals may enter the market in the near future. Genetically modified organisms hold the most promise in overcoming the problems of agricultural production and food quality as well as the prevention of illness. However, the introduction of GMO is connected with serious concern for safety of foods, possible environmental risks and economical risks. The special legislation on food testing and GMO releasing has been adopted in most of developed countries including EU members in order to protect from the negative effects of GMO.
PL
W pracy przedstawiono wyniki badań własnych oraz dane literaturowe dotyczące podobieństwa genetycznego Lolium perenne i L. multiflorum. Przedstawiono możliwości wykorzystania markerów molekularnych jako markerów gatunkowych oraz omówiono stan badań nad mapowaniem genomu Lolium.
EN
Results of authors’ own research and literature data review dealing with genetic similarity between Lolium perenne and L. multiflorum were presented. The possibility of using molecular markers as species specific markers and the studies on genome mapping were discussed.
EN
Closely related Pinus species, mountain pine (Pinus mugo Turra) and Scots pine (Pinus sylvestris L.), belong to native woody species in the Tatra National Park (TPN, southern Poland). Their occurrence in close proximity can lead to the formation of natural hybrids known as Pinus × rhaetica, which is a woody, often polycormic form. Pinus×rhaetica is described in the TPN, but there has been a great deal of disagreement over its origin. The goal of the studies was to verify the taxonomic status of individuals identified as Pinus×rhaetica that grew in the eight stands together with P. mugo and P. sylvestris by SSAP (Sequence Specific Amplification Polymorphism) analysis of transposon insertional polymorphism. In total, 34 Pinus×rhaetica, 25 P. mugo and 27 P. sylvestris individuals were tested in addition to 20 individuals of P. uliginosa from ‘Torfowisko pod Węglińcem' and ‘Wielkie Torfowisko Batorowskie' as well as 25 individuals of P. uncinata from the Austrian Alps as the control groups. Four transposon sequences were employed: a DNA transposon from the CACTA family, Tpo and retrotransposons – two gypsy (Ogre, IFG7) and one copia like (Bare). All species belonging to the Pinus mugo complex are highly variable with 49−81% polymorphic loci and genetic diversity, HTequals 0.228−0.307 with the highest values in Pinus×rhaetica. Surprisingly, P. sylvestris proves to be the least variable species, likely because of a narrow gene pool in small, scattered stands in the Tatras. Very low Nei's genetic similarities between P. sylvestris and Pinus mugo complex, especially in comparison with P. uliginosa (I=0.548) and P. mugo (I=0.558) exclude unequivocally the possibility of spontaneous hybridization among these taxa. Thus, it undermines the hypothesis about hybrid origin of Pinus×rhaetica in the Tatras. It proves to be a morphological form of P. mugo as assessed from the Nei's coefficient, I=0.985 which is well within a range of conspecific populations. Finally, none of the studied individuals of Pinus×rhaetica are derived from seeds of Alpine P. uncinata.
15
Content available Gene segregation in a barley DH population
51%
EN
A large population of anther culture-derived barley regenerants and their progeny was tested for allele segregation at 1 isozyme and 8 morphological marker loci. The segregation of genetic markers was examined separately for haploid, diploid and polyploid regenerants. All the 9 analysed genes except al (albino lemma) on chromosome 3 segregated according to the expected 1:1 ratio in the microspore-derived barley population. There was no difference in allele distribution between haploid and diploid regenerants. Among the limited number of 34 analysed tetraploids a significant excess of the dominant allele at locus о (orange lemma) of chromosome 6 was also observed. The recombination frequency between linked genes (n - lk2 on chromosome 1 and r - s on chromosome 7) estimated in the DH population did not differ significantly from recombination rates calculated in F₂ progeny or presented in barley chromosome maps. The phenomenon of gametic selection is discussed in relation to the genotype dependency of anther culture response and procedures used for DH production in barley.
EN
The obligatory human pathogen, Mycobacterium tuberculosis, is the most important etiological factor of tuberculosis. Unfortunately, there is little information about genetic diversity of this pathogen. The main aim of this research was the estimation of genetic diversity of M. tuberculosis on the basis of various categories of DNA markers. The genome of 32 strains were scanned by DNA markers such RAPD, IS6110 and catalase-peroxidase katG gene. All 162 identified loci were polymorphic. The genetic diversity coefficient (HT) of M. tuberculosis was 0.32 for RAPD and 0.27 for IS6110. There were 14 alleles in katG gene. All strains were characterised by the individual molecular pattern. Genetic similarity varied from 0.13 to 0.94 (RAPD markers) and from 0 to 1 for (IS6110). M. tuberculosis strains did not represent a clonal structure, single source of transmission and epidemiological relationships as well. The applied DNA markers proved to be highly efficient for analysis of genetic structure of M. tuberculosis.
EN
Dreissena polymorpha inhabits about 46.5% of the bottom area in Lake Dabie. It is most abundant in the northern part of the lake and sporadically occurs in its southern part. The average density of the zebra mussel is 891 individuals/m², while its wet weight is 1374 g/ m². In the settled areas the density of the zebra mussel reaches 1734 individuals/ m². There were presently established 7 age-groups from 0 to 6+. The highest number of specimens occurred in the age-groups between 1+ and 3+, while the lowest number - in the groups 0, 5 and 6+. Strong eutrophication and pollution of Lake Dabie on its southern side, combined with sedimentation of the extensive amounts of seston carried in by the Płonia and Regalica rivers, do not create favourable conditions for development of Dreissena. D. polymorpha plays a very positive role in the lake ecosystem through its biofiltrating action, contributing thus to an increase of water clarity and to limitation of phytoplankton development through cumulating nutrients in its biomass. Electrophoretic analysis of 9 enzymatic loci revealed strong polymorphism of the studied population of the zebra mussel: percent of polymorphic loci - 100, mean number of alleles in locus – 3.4, coefficient of expected heterozygosity per locus in the population, HS - 0.335, percentage of separate genotypes - 69%, in this number unique genotypes - 58%. A very strong scattering of the alleles was stated within the entire population. In each aggregation, on average, 90% of the specimens have a separate genotype. Each of the five defined groups of D. polymorpha, representing profiles I-V, respectively, had similar genetic composition. The values of the genetic similarity among the studied groups of the zebra mussel ranged from 0.96 to 0.99.
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