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SSR based characterization of peach (Prunus persica L.) and apricot (Prunus armeniaca L.) varieties cultivated in Hungary
17-24Views:263The SSR (Simple Sequence Repeat) markers allow the discrimination of the cultivars and determination its specific DNA fingerprints. The aim of this research was to evaluate fifteen apricot (Prunus armeniaca L.) and fifty-one peach (Prunus persica L.) genotypes cultivated in Hungary to obtain their DNA fingerprints in 6 SSR (Simple Sequence Repeats) loci by allele numbers and sizes.DNAs were extracted from leaves. PCR was carried out with CY-5 fluorescent labeled Prunus microsatellite markers and the products were separated on polyacrylamide gel with ALF (Automated Laser Flourometer)-Express II.According to our results, in the case of peach genotypes, all 6 SSRs were able to amplify alleles. UDP 96 005 was the most informative marker and UCDCH 17 was the least due to its monomorphic pattern. Regarding the apricot samples BPPCT 041 did not amplify any allele. In the case of P. armeniaca UDP 96 005 had the highest heterozygosity index as well and the highest number of alleles. The least informative marker was the UCDCH 17. Since the 6 SSR were not enough to discriminate the apricot and peach genotypes, it is suggested to use more SSR primers. -
Effect of arginine, putrescine and spermidine on the polyamine, proline and chlorophyll content of tobacco (Nicotiana tabacum L.)
39-43Views:117Polyamines, such as spermidine (Spd) spermine (Spm) and their direct precursor, the diamine putrescine (Put) are vital and essential aliphatic amines which are also present in plants. Although ethylene and polyamines are also involved in fruit ripening, the genes coding them must also take part in other biosynthetic pathways. In the ethylene and polyamines play an important role in development of salt stress tolerance, and in responses for biotic and abiotic stresses. Exogenous application of all three main polyamines (Put, Spd, Spm) increase salt tolerance of plants, but, accordingly to previous experiments, spermidine has the main effect on the enhancement of salt tolerance. Nicotiana tabacum L. plants were grown in vitro on MS medium, the treatments were as follows: arginine (150 mg l-1), putrescine (10 mg l-1), spermidine (10
mg l-1). Proline, chlorophyll a, b and polyamine contents were measured. The obtained results show that the arginine decarboxylase and the spermidine synthase genes involved in polyamine metabolism, cannot be enhanced by exogenous addition of their precursor molecules. On the contrary, the spermine synthase gene has a positive effect to the lower-class forms of polyamines. -
Selection of powdery mildew resistant and susceptible grapevine genotypes with molecular markers
100-104Views:108Incorporation of competitive quality and resistance against the most important fungal diseases (powdery and downy mildew) in a cultivar is one of the most important aims of grapevine breeding. In the 20th century, the most advanced results in grapevine resistance breeding were achieved by French researchers. They used resistant cultivars in more than 30% of their growing areas. In these varieties, North American wild Vitis
species were the resistance gene sources. The discovery of immunity-like resistance of Muscadinia rotundifolia opened new perspectives in resistance breeding. M. rotundifolia harbours a dominant powdery mildew gene, providing resistance in highquality cultivars after back-crosses with V. vinifera varieties. M. rotundifolia has been involved in the Hungarian grape breeding programs since 1996, thanks to a French-Hungarian variety exchange. In addition to traditional selection methods, application of MAS (Marker Assisted Selection) based on various types of
molecular markers, can provide additional tools for these efforts. Run1 locus, responsible for powdery mildew resistance, was identified in Muscadinia rotundifolia. Molecular markers closely linked to this locus are very significant in screening progenies deriving from M. rotundifolia and V. vinifera crosses, making possible the discrimination between resistant and susceptible genotypes at DNA level. In our analyses BC5 progeny of {(M. rotundifola×V. vinifera) BC4}×Cardinal (V. vinifera) tested for powdery symptoms were analysed with PCR-RFLP (GLP1- 12P1P3) and microsatellite markers (VMC4f3.1, VMC8g9). Our results proved the applicability of the linked markers and reliability of marker assisted selection. -
Isolation of promoters of tissue and ripening-specific strawberry genes by TAIL-PCR and bioinformatic characterization of the sequences
91-99Views:45Isolation of ripening- and tissue-specific promoters has become a very important subject of the genetic regulation and plant physiology research in recent years. It could be possible to reveal the regulation of gene expression, and it may be a very useful approach in the biotechnology. In our work, we have isolated promoter regions of genes exhibiting ripening- and tissuespecific expression in our previous experiments, and the data were
characterized by bioinformatic methods. In the sequence of the ripening-specific Spatula and ACC-oxidase promoters (ACCoxidase is one of the key-enzymes of ethylene biosynthesis, directly related to the process of ripening); we could identify auxin- and ethylene-related cis-regulatory elements. This suggests that there is an interaction between ripening and ethylene-synthesis, in case of non-climacteric strawberry, too. We investigated the promoter regions of three green receptacle-specific genes (putative nitrilaselike protein, Ring transcription factor and an aquaporin protein)
and we could identify several regulatory elements, which refer to hormonal regulation. Additionally, we could find several cisacting elements which associated with stress-responsiveness and endospermium-specific expression. -
Application of microsatellite fingerprints for pedigree analysis of Hungaricum grapevine varieties
71-77Views:99the Carpathian Basin were involved into our examination, which aimed at genotyping their accessions. DNA fingerprints of 101 varieties were determined with 6 microsatellite markers till 2005, resulting in successful discrimination of the accessions. Based on these results for pedigree determination, even more cultivars and primers were involved into the analyses. For studying the origin of Csabagyöngye and for proving the parent-progeny relations of Irsai Olivér and Mátrai muskotály, 19 microsatellite markers were applied, while 11 were selected for tracing the origin of Királyleányka. Genetic distances between the varieties were estimated with cluster analysis and demonstrated by dendrogram, proving that the varieties can be discriminated from each other based on the microsatellite allele sizes. Pedigree of Irsai Olivér and Mátrai muskotály has been confirmed by microsatellite allele size results, searching for the parents of Csabagyöngye and Királyleányka is in progress, since the molecular-marker based pedigree does not correspond with the putative origin of these cultivars. Our results excluded progeny-parent relationships in the
Csabagyöngye-Bronnerstraube-Muscat ottonel (Ottonel muskotály) and the Királyleányka-Kövérszőlő combinations.