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The taxon currently named P. officinalis subsp. banatica has been treated as a subspecies of P. officinalis by most authors. Recent genetic studies revealed that this taxon is an ancient allotetraploid hybrid carrying the genes of P. mairei and the ancestor of P. officinalis. Based on its current polyphyletic status, degree of genetic and morphological divergence, its geographical distribution and unique genetic constitution I argue that this viewpoint is incorrect, and this taxon should be recognised as an independent species.

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Porcine circovirus type 1 (PCV1) is considered to be a non-pathogenic virus detected in cell cultures, vaccines or products used for cell culture preparations, all of them of porcine origin. Serological evidence and genetic studies suggested that PCV1 was widespread in domestic pigs. The presence of PCV1 in wild boars in Germany was also described using serological methods. This paper reports the first detection of PCV1 in Hungarian wild boars. Samples were collected at slaughterhouses and processed for polymerase chain reactions. The complete genome of PCV1 detected in the samples was determined and compared with the available PCV1 sequences of the GenBank database. The genomes formed two distinct clusters with minimum differences, where the Hungarian wild boar PCV1 (WB-H8) grouped together with genomes originating from domestic swine from China and Australia and with a genome detected in a porcine pepsin product.

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Random Amplified Polymorphic DNA (RAPD) technique is a powerful tool for genetic studies. It can be also applied for determination of bacterial species. The goal of this work was to optimize conditions for RAPD reaction, and to obtain RAPD patterns specific for some plant-associated bacteria. RAPD could be a good choice for screening and preliminary bacterial determination. Application of RAPD can determine that some of bacterial species are not reason of infection, and make additional tests for them unnecessary. This can provide time, labor, and as well as money saving, which is important particularly if expensive tests are applied. Optimization of reaction conditions in this work made possible good repeatability of RAPD electrophoretic patterns for particular bacterial species.

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For a molecular genetic study on Hungarian populations of European corn borer L5 stage larvae were collected from 14 places of three different regions of the country (uni- and bivoltine ecotypes). Additionally, the study included larvae from Egypt, too (multivoltine ecotype). Molecular examinations of European corn borer larvae using the study of mitochondrial cytochrome b (cyt b) revealed that by single strand conformation polimorphism (SSCP) the populations found in Hungary represented the same haplotype. Even the Egyptian sample showed no genetic divergence. Some minor deviatons were found in the case of a sample from Székkutas, but that did not prove the genetic divergence of the bivoltine ecotype either, since the other samples of South-East Hungary did not display this kind of genetic variation. On the basis of our investigations it can be said that the univoltine and bivoltine generations, have uniform genetic complements.

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Until now, testing for resistance to FHB in cereals has been expensive and affected by differences in environmental conditions. Rapid screening methods are needed. Recently it was discovered that in wheat good extrusion of anthers (AE) is associated with high resistance to FHB. In one genetic study a fan-shaped pattern was found: The variation and level of FHB/DON was reduced when AE increased. In order to verify these results, 69 varieties of winter wheat from Germany and Scandinavia and 136 varieties of spring wheat from GRAMINOR breeding in Norway were tested for AE and resistance to FHB and DON. The fan-shaped distribution was found also here. Accordingly, AE is recommended as a new and inexpensive screening method for low FHB. When sufficient moisture is available in the period before flowering and wind do not remove anthers, field selection for AE could be made, in other cases greenhouse selection is recommended.

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The increasing economic importance of triticale (×Triticosecale Wittm.) makes this synthetic hybrid cereal an interesting object of genetic studies. Genomic regions (QTL) of morphological winter triticale traits were determined using the mapping population of 89 doubled haploids lines (DHs) developed from F1 hybrid of cv. ‘Hewo’ and cv. ‘Magnat’ accompanied with the genetic map consisting of 20 linkage groups assigned to the A (7), B (7), and R (6) genomes (total of 3539 DArT, SNP-DArT and SSR markers, length of 4997.4 cM). Five independent experiments were performed in the field and greenhouse controlled conditions. A total of 12 major QTLs located on 2B, 5A, 5R, and 6B chromosomes connected to the stem length, the plant height, the spike length, the number of the productive spikelets per spike, the number of grains per spike, and the thousand kernel weight were identified by a composite interval mapping (CIM).

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Fruits are rich sources of flavonoid polyphenolic compounds that seem to be associated with favourable healtheffects. Commonalities and differences are well known in the flavonoid contents of different fruit crops, which suggest alterations in the flavonoid biosynthesis pathway of fruit tissues. This review aims to collect data from molecular genetic studies on the structural and regulatory genes in grape, berries, citrus, pomes and stone fruits to get impression on the state of the art of this field of science. Results indicate that the expression of flavonoid genes is a genotype-dependent and developmentally regulated process. In addition, genetic alterations resulting in specific changes in flavonoid composition are also highlighted. Analysis of colour mutants of grape, bilberry and orange identified the genes responsible for the altered phenotype, and this strategy might offer valuable tools to identify several other candidate genes in different fruits. The application of such data is also discussed in relation with the development of molecular markers.

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Absztrakt

Jelen tanulmány elsődleges célja, hogy áttekintse a diszlexia meghatározásának módszertani buktatóit, bemutassa a diszlexia első genetikai vizsgálatait, valamint a géntérképezés elmúlt öt évben született eredményeit. Az utóbbi különösen „forró” téma, mivel számos jelenleg folyó kutatás verseng az első olyan megbízható modell megalkotásában, amely a diszlexia valódi és megbízható genetikai faktorára derít fényt. A géntérképezési vizsgálatok több kromoszómán tíz olyan területet azonosítottak, amelyet DYX területeknek nevezünk. Újabb genetikai vizsgálatok azt is kiderítették, hogy a DYX területeken négy olyan gén található, amely a diszlexiához köthető: DYX1C1 a 15-ös, KIAA0319 és DCDC2 a 6-os, és ROBO1 a 13-as kromoszómán. A funkcionális vizsgálatoknak azt is sikerült kimutatnia, hogy mind a négy gén különleges szerepet játszik az agyfejlődésben, ugyanakkor joggal feltételezhető, hogy ezek a gének és területek csupán egy töredékét képviselik a human lexinomnak. A human lexinom fogalma, amelyet a közelmúltban Gibson és Gruen (2008) vezetett be, magában foglal minden olyan genetikai összetevőt, amely meghatározóan felelős a nyelv és olvasás fejlődéséért.

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Potato, Solanum tuberosum L. (2n = 4x = 48), is an autotetraploid species, the breeding of which at the tetraploid level is complicated by tetrasomic inheritance. Dihaploids (2n = 2x = 24) from the tetraploid cultivated potato have great potential for breeding and genetic studies. The common method deployed to obtain potato dihaploids is to make interspecific-interploidy (4x × 2x) crosses between a tetraploid seed parent and special clones from the diploid S. phureja as pollinator. Pollinators carrying a marker gene have been used, but unfortunately, these clones were very weak, with rare flowering and low male fertility under the given conditions. To find a suitable pollinator, three clones were selected from S. phureja based on flowering, pollen shed and male fertility and were crossed with five cultivated tetraploid potatoes to evaluate their dihaploid induction ability. A total of 1529 interploidy crosses were made, resulting in 1116 berries and 1456 seeds. The progeny were divided into two groups based on stem, flower and tuber colour: hybrids and non-hybrids (putative dihaploids). Chromosome counting in non-hybrid genotypes detected 39 dihaploids. The clone phu 3 and cv. Picasso, with 12.1 and 10.7 dihaploids per 100 berries, respectively, were the best dihaploid inducer and seed parent for dihaploid production.

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Abstract  

Deaths and resurrections of the subject. Comparative Literature studies have for some time now been engaged in a new phase in which the internationality of the subject matter is no longer at stake. In the global village literatures develop both transnationally and intranationally as parts of wider cultural patterns. Thus to reflect upon literature is increasingly a philosophical matter involving battles of Weltanschauungen. The problematic of the subject is a case in point. Subjectivity as embodiment of the individual human existent has come to be viewed negatively, particularly in the light of feminist and postcolonial theories, which question the universality of a subject built on objectifying the Other; thus the erstwhile object becomes in turn subject, and the equation is once again incomplete. We wish to examine a sampler of diverse, indeed scattered instances of a renewed interest in the problematic of the subject. For example, far from being dead, the Author reappears massively in biographical and autobiographical writings, and is tracked through genetic studies. The subject writes itself in interstices and margins, in discontinuity, elusiveness and uncertainty, as process rather than essence; but we hypothesize that this is in many literary and cultural contexts the very mode of its rehistoricization.

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