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1.
Acta Biol Hung ; 64(2): 231-48, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23739891

RESUMO

The aim of this paper was to find possible link between molecular and morphological similarities of 38 Hungarian white grape varieties. Three aspects of morphological and molecular similarity were assessed in the study: comparison of the ordered variety pairs, assessment of molecular and morphological mean similarity differences and separation of varieties into similar groups by divisive cluster analysis to define (DIANA). Molecular similarity was calculated from binary data based on allele sizes obtained in DNA analysis. DNA fingerprints were determined at 9 SSR loci recommended by the European GrapeGen06 project. Morphological similarity was calculated on the basis of quantitative morphological descriptors. Morphological and molecular similarity values were ordered and categorized after pairwise comparison. Overall correlation was found to be weak but case by case assessment of the variety pairs confirmed some coincidence of molecular and morphological similarity. General similarity position of each variety was characterized by Mean Similarity Index (MSI). It was calculated as the mean of n-1 pair similarity values of the variety concerned. Varieties were ordered and compared by the difference of the index. Five varieties had low morphological and high molecular MSI meaning that they share several SSR marker alleles with the others but seems relatively distinct according to the expression of their morphological traits. Divisive cluster analysis was carried out to find similar groups. Eight and twelve cluster solutions proved to be sufficient to distinct varieties. Morphological and molecular similarity groups partly coincided according to the results. Several clusters reflected parent offspring relations but molecular clustering gave more realistic results concerning pedigree.


Assuntos
Alelos , DNA de Plantas/genética , Loci Gênicos/fisiologia , Repetições de Microssatélites/fisiologia , Filogenia , Vitis/genética , Hungria
2.
Acta Biol Hung ; 57(1): 57-69, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16646525

RESUMO

Identification and classification of numerous Festuca species is still a difficult problem due to the close morphological resemblance. The most difficult fine fescues to identify belong to the Festuca ovina aggregate, which is the largest group in the genus Festuca. Many taxons are considered to be separate species based on quantitative taxonomic characters, differences in ploidy level or the structure of sclerenchyma cells. In order to evaluate the taxonomic value of DNA-based markers, sequence analysis of the internal transcribed spacer (ITS1-5.8S-ITS2) region and the chloroplast trnL (UAA) intron was performed in the ten most problematic fine fescues belonging to the Festuca ovina aggregate. Intraspecific ITS variants were found in a single case while in other cases only intragenomic ITS polymorphisms were detected with 1-2 ambiguous positions. Among the sequences of the trnL (UAA) intron even intragenomic polymorphisms were not detected in any of the Festuca species studied. Thus, the results do not support the species status of these ten taxa.


Assuntos
DNA de Cloroplastos/genética , DNA Intergênico/genética , DNA de Plantas/genética , DNA Ribossômico/genética , Festuca/genética , Variação Genética , Íntrons/genética , Sequência de Bases , Festuca/classificação , Citometria de Fluxo , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Polimorfismo Genético
3.
Acta Biol Hung ; 53(3): 317-24, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12371611

RESUMO

Molecular polymorphism of six species of Thysanoptera of both sexes, collected from different locations and host plants in Hungary was studied by using RAPD-PCR technique. The specimens were classified according to sampling sites (Gödöllö, Nagykovácsi and Valkó), host plants (Lathyrus tuberosus, Medicago sativa, Taraxacum officinale, Trifolium pratense), sexes, and larvae in case of Aeolothrips intermedius. On the basis of the total of 103 fragments generated by 15 RAPD primers the genetic distances were calculated by cluster analysis using simple matching method. The dendrogram resulted in two main groups: Aeolothripidae (Aeolothrips intermedius) and Thripidae (Frankliniella intonsa, Kakothrips robustus, Odontothrips confusus, Thrips dilatatus and T. tabaci). Within the family Thripidae two subgroups were observed including (i) F. intonsa, T. dilatatus and T. tabaci, and (ii) K. robustus and O. confusus. Two population-specific and one sex-linked fragments were identified by the RAPD primers, OPQ 14, NO11 and OPA08, respectively.


Assuntos
Insetos/genética , Polimorfismo Genético , Animais , Sequência de Bases , Primers do DNA , Feminino , Masculino , Reação em Cadeia da Polimerase , Técnica de Amplificação ao Acaso de DNA Polimórfico , Especificidade da Espécie
4.
Acta Biol Hung ; 52(2-3): 345-54, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11426869

RESUMO

RAPD (randomly amplified polymorphic DNA) and AP-PCR (arbitrarily primed PCR) were utilized to establish the genetic diversity of 19 Populus genotypes. A set of 40 primers of random sequence was tested, of which 35 exhibited polymorphism. Eighteen primers generated 162 easily detectable bands between 250 and 2,500 base pairs in size, sufficient to distinguish between the genotypes. Similarity measures, cluster and multidimensional scaling analysis were performed to evaluate the RAPD and AP-PCR data. Our study demonstrated that in most instances similarity in the RAPD and AP-PCR banding patterns reflected the relationship due to origin. Nineteen primers gave a species or hybrid-specific pattern. One primer generated a specific pattern in P. euramericana. Ten primers produced specific fragments in VIF (P. alba), 4 primers in KOR (P. pyramidialis x P. berolinensis) and 4 primers in UNA and RAS (P. trichocarpa x P. deltoides). The results of this study demonstrated that RAPD or AP-PCR can be used to distinguish between poplar genotypes.


Assuntos
Variação Genética , Magnoliopsida/genética , Árvores/genética , Genótipo , Magnoliopsida/classificação , Reação em Cadeia da Polimerase , Técnica de Amplificação ao Acaso de DNA Polimórfico , Especificidade da Espécie , Árvores/classificação
5.
Acta Biol Hung ; 46(1): 51-9, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8714763

RESUMO

In order to develop a simple and feasible approach to achieve high frequency plant regeneration for protoplast isolation and transformation experiments, a method was elaborated by using a new type of explant (petiole segments) for the four Populus nigra genotypes. Callus initiation from the petioles took place on N6 medium containing 2,4-D (0.1-1 mg/l). The highest rate of callus initiation (100%) was achieved when the basic medium was supplemented with 0.5 mg/l of 2,4-D, in all tested genotypes. For shoot regeneration, calli were transferred to MS and WPM medium supplemented with BA (1.0-2.5 mg/l) and NAA (0.2 mg/l). Multiple shoot regeneration was observed in each shoot induction medium. The highest rate of shoot regeneration (6.83 shoot/callus) was observed on MS medium containing 2.5 mg/l BA and 0.2 mg/l NAA. The results showed highly significant differences between the media. There was no significant difference between the genotypes and genotype x medium interaction.


Assuntos
Fenômenos Fisiológicos Vegetais , Plantas/genética , Meios de Cultura , Genótipo , Protoplastos , Regeneração/genética , Transformação Genética , Árvores/genética , Árvores/fisiologia
6.
Acta Biol Hung ; 44(2-3): 189-96, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8184629

RESUMO

Somatic embryogenesis from immature soybean cotyledons was induced on Murashige & Skoog medium, supplemented with 2,4-dichlorophenoxyacetic acid. The full developmental analyses of primary and secondary somatic embryogenesis was monitored by scanning electron microscopy. The developmental stages of embryogenesis from the first unequal cell division through the three- and four-cell embryos, and multi-cell globular and heart shape embryos, to the fully developed plants were determined. When the globular stage embryos were incubated on the embryo maturation medium for 4 to 6 weeks a secondary embryogenesis was observed and scanned. Chimeric embryos with epidermis zones similar to mature leaf were characterized.


Assuntos
Glycine max/embriologia , Meios de Cultura , Microscopia Eletrônica de Varredura , Regeneração/fisiologia , Glycine max/fisiologia , Glycine max/ultraestrutura
7.
Acta Biol Hung ; 44(2-3): 197-210, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8184630

RESUMO

Rice (Oryza sativa L.) cells, grown under a continuous stress of 1.5% NaCl, produced a homogeneous mass of dry, compact, nodular callus with high regeneration potential, typical of embryogenic cultures. When transferred and subcultured in conditions without salt, the pre-adapted cells underwent several changes, leading to the formation of heterogeneous populations that comprised different cell types. This newly formed callus, in the 6-month period without salt stress, resembled cell populations of the untreated cultures. These cells are characterized by fast growth, high water content, friable texture, high salt sensitivity and low culture response. They also produce a protein pattern in the SDS-PAGE analysis, that differs from that of cells cultured under the continuous salt stress. This observation indicates that different salt stress regimes induced different responses in the cultured cells in rice.


Assuntos
Oryza/efeitos dos fármacos , Cloreto de Sódio/farmacologia , Adaptação Fisiológica , Tolerância a Medicamentos , Oryza/citologia , Oryza/fisiologia , Fenótipo , Proteínas de Plantas/biossíntese , Regeneração/efeitos dos fármacos , Regeneração/fisiologia , Cloreto de Sódio/administração & dosagem
8.
Plant Cell Rep ; 11(5-6): 266-9, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24203137

RESUMO

Plant regeneration from callus of intergeneric hybrid Agropyron repens (L.) Beauv. x Bromus inermis Leyss cv. nanus (AGROMUS) was carried out on a new culture medium designated medium-F. Within 21 days of the plating of inflorescence primordia the initiated callus showed globular structures. From the 21st day of culture, one step plant regeneration occurred on the callus without subculture. The new basal medium reported in this work was effective in callus initiation and plant regeneration of the hybrid AGROMUS by (i) the reduction of the total ion strength (2.6 g/l, 22.5 mM) of macroelements compared to MS (4.5 g/l,45.2 mM), (ii) the use of NH4NO3 as the sole N-source, and (iii) the application of KH2PO4 at an 8 times higher concentration (1160 mg/l,8.5 mM) when compared to the Murashige and Skoog medium composition. This medium provided a 2 to 10 fold reduction in the 2,4-dichlorophenoxyacetic acid supplement needed for the callus initiation and one step plant regeneration after a gibberellic acid (2 mg/l, for 5 days) pretreatment of tillers. The regenerated plantlets were subcultured in multi-shoot culture and potted in soil to grow for further analysis.

9.
Acta Biol Hung ; 42(4): 313-21, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1841482

RESUMO

Somatic embryogenesis and organogenesis were induced on immature cotyledons of different soybean cultivars. The anatomical investigation of morphogenesis proved neomorph differentiation instead of somatic embryos, and leaf formation instead of shoot development. While normal embryos were induced in 0-3.1% of the explants, neomorphs developed at a much higher rate i.e. in 10.5-78.9% depending on the genotype. Likewise organogenesis preferably followed the pathway of leaflet development (3.1-26.3%) than that of shoot tip formation (0-2.6%). Low plant regeneration frequency of soybean can partly be explained with these two alternative abortive pathways of morphogenesis probably induced with higher frequency than the normal pathways by the generally used in vitro methods.


Assuntos
Desenvolvimento Vegetal , Técnicas de Cultura , Plantas/embriologia , Glycine max/embriologia , Glycine max/crescimento & desenvolvimento
10.
Acta Biol Hung ; 40(4): 381-94, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2486728

RESUMO

The organ-specific somaclonal variation means the differences between the variability of somaclones originated from different somatic tissue of plant. Significant differences in some agronomical characters were achieved among somaclones of seed and plumule meristem origin. The ploidy-dependent somaclonal variation means the differences between the variability of somaclones originated from different ploidy-level tissue. Increased variation among regenerated plants was postulated by origin from cultured cells of reduced ploidy level. The comparison of somaclonal variation in the progenies of diploid plants regenerated from callus of haploid and diploid origin supported the ploidy dependent theory. The pollenhaploid somaclone method (PHS-method) was developed and tested for utilization somaclonal variation in rice breeding. The PHS-method comprises the two well-known and widely applied in vitro methods which are the androgenesis (another culture) and genetic instability of cultured haploid somatic cells (callus cultures). Developmental varieties produced by this breeding sheme are under certification in Hungary.


Assuntos
Plantas/genética , Variação Genética , Especificidade de Órgãos , Fenótipo , Fenômenos Fisiológicos Vegetais , Plantas/anatomia & histologia , Ploidias , Regeneração
11.
Acta Biol Hung ; 40(1-2): 127-36, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2633578

RESUMO

Adequate cell dehydration is the precipitating element in the successful cryopreservation of plant cells and organs. This could be achieved by using different cooling rates, transfer temperatures and cryoprotectants. Experiments were performed to determine these critical points in the freeze preservation procedure of Cannabis sativa (L.) suspension cultures. The explants were frozen at a cooling rate of 2 degrees C/min, while the transfer temperatures were -10 degrees C, -20 degrees C, -30 degrees C, -40 degrees C and -50 degrees C. The applied cryoprotectants were the DMSO, glycerol, proline and PEG in different concentration. The highest viability (58%) was obtained by using 10% DMSO and at -10 degrees C transfer temperature. The optimum transfer temperature varied remarkably by different cryoprotectant concentrations indicating the importance of their interactions.


Assuntos
Criopreservação/métodos , Células Vegetais , Cannabis/citologia , Sobrevivência Celular , Crioprotetores , Temperatura
12.
Plant Cell Rep ; 8(3): 174-7, 1989 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24233097

RESUMO

Three main types of callus have been selected from seeds of salt marsh grass(Puccinellia limosa (Schur.) Holmbg.) subcultured on Murashige and Skoog medium supplemented with 2,4-dichlorophenoxyacetic acid and kinetin. Callus type I differentiated only occasionally. Callus type II produced roots but no shoots under all tested culture conditions. Both green (47 %) and albino plants have been obtained from the embryogenic callus type III. Callus type III was divided into two subtypes (greening and non-greening) according to the presence or absence of green spots. Separated greening embryogenic callus gave up to 87 % green plants, whereas non-greening callus produced only 4 %.

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