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  • Propagation from root cuttings for black locust (Robinia pseudoacacia L.) improvement in Hungary: a review
    39-41.
    Views:
    247

    Black locust (Robinia pseudoacacia L.) is a valuable stand-forming tree species introduced to Europe approximately 400 years ago from North America. Today it is widely planted throughout the world, first of all for wood production. In Hungary, where black locust has great importance in the forest management, it is mainly propagated by seeds. But since the seed-raised plants present a great genetic variation, this type of propagation can not be used for Robinia’s improved cultivars. In the Hungarian black locust clonal forestry, propagation from root cuttings can be used for reproduction of superior individuals or cultivars in large quantities. However, this method demands more care than raising seedlings from seeds and can be applied with success in well-equipped nurseries.

  • Production of transgenic carnation with antisense ACS (1-aminocyclopropane44-carboxy late synthase) gene
    104-107.
    Views:
    161

    Dianthus chinensis and Dianthus caryophyllus varieties were tested for shoot regeneration from leaf and petal explants and transformed with Agrobacterium tuniefaciens strains (EHA 105 and LBA 4404) harbouring an apple derived ACS cDNA in antisense orientation in order to reduce ethylene production and influence the ethylene dependant traits in carnation. After transformation regenerating shoots were selected on MS medium containing 50-75-100-125-150 mg/1 kanamycin and supplemented with 1 mg/1 BA, 0.2 mg/1 NAA. Transgene integration was proved by PCR analysis with npt II spcific primers followed by Southern hybridisation of DNA isolated from green shoots on medium containing 150 mg/1 kanamycin. Several putative transformants were subjected to RT-PCR in order to examine the npt 11 expression at mRNA level. Both the transformant and the non-transformant plants were potted into glasshouse to observe the effect of changed ethylene production on flowering time, petal senescence and vase life.

     

  • Effects of different cytokinins on the shoot regeneration from apple leaves of 'Royal Gala' and 'M.26'
    69-75.
    Views:
    193

    The effects of different types of cytokinins on the shoot regeneration from leaf explants of apple scion 'Royal Gala' and apple rootstock 'M.26' were evaluated. Regeneration media contained either thidiazuron, or 6-benzylaminopurine, or meta-topolin, or zeatin, or kinetin, or their N9-ribosides, respectively, in the concentration range 0.5 to 8.0 mg 1-1. Effects of 'these cytokinins were evaluated on the percentage of regeneration (R%) and that of vitrification (V%) and on the number of regenerated shoots per explant (SN). Organogenetic index (0I) calculated from these data was used for the evaluation of efficacy of cytokinins. The course of shoot organogenesis also was followed using stereomicroscope. Types and concentrations of cytokinins applied in the regeneration media influenced each parameter significantly and the regeneration answer was strongly genotype-dependent. The best regeneration (SN: 11.08, 01: 7.5) was achieved in `Royal Gala' by using TDZ in concentration of 0.5 mg 1-1 (2.271,1M). There was a clear relationship between the effect on the regeneration efficacy and the chemical structure of cytokinins considering classical cytokinins, namely N9-ribosides applied in less concentration than non­ribosides have the same or best regeneration effects except for 6-benzylaminopurine riboside. However, similar relationship could not be detected in the case of 'M.26'. SN was the highest (3.22) using 6.5 mg 1-1 (18.2011M) 6-benzylaminopurine riboside or 8.0 mg 1-1 (21.44 µM) meta-topolin riboside (3.18). SN was not significantly lower (3.12) by using 2.0 mg 1-1 (9.08 1M) TDZ, however, OI was about half as big (0.63 compared to 1.29 or 1.74 with 6-benzylaminopurine riboside or meta-topolin riboside, respectively). 'Royal Gala' had higher organogenetic ability, than `M.26': 3.5-fold higher shoot number per explant and more than 4-fold higher organogenetic index was reached with this cultivar than with 'M.26'. Moreover, the similar developmental stage of shoots could be observed 3-5 days earlier than in 'M.26' and if explants of 'Royal Gala' were further cultured with 3 weeks, SN increased from 11.08 to 24.42 on TDZ-containing regeneration medium, which might suggest higher organogenetic ability, too.

  • Ripening related processes in strawberry, a nonclimacteric fruit: a short overview
    105-109.
    Views:
    180

    Fruits are essential part of the human diet: they provide vitamins, minerals, antioxidants to the mankind. Physiologically they can be divided into two groups-climacteric and nonclimacteric - depending if they display any respiratory peak and dramatic increase in ethylene biosynthesis or do not. Ethylene is a gaseous hormone playing a very important role in several physiological processes in plants. While climacteric fruits, like apples, bananas, tomatoes, peaches, apricots show increased ethylene biosynthesis and dramatic respiratory peak during their ripening, nonclimacteric fruits, like strawberries, grapes, citrus do not.

    The most widely used fruits for studying nonclimacteric ripening are strawberries: several papers are focusing on the identification and characterization of ripening related genes from this plant. Therefore here we attempt to summarize the most important advances in strawberry fruit development, and ripening.

  • The in vitro and in vivo anatomical structure of leaves of Prunus x Davidopersica ‘Piroska' and Sorbus rotundifolia L. ‘Bükk szépe'
    92-95.
    Views:
    209

    Immature in vitro leaves showed similar structure of the mesophyll tissue to the immature field-grown (in vivo) leaves of Prunus x davidopersica `Piroska'. Mature leaf anatomical characteristics of in vitro plantlets differ from the field-grown plants. The mesophyll tissue of in vitro plantlets were thinner than the in vivo plants and consisted of only one layer palisade parenchyma, the shape of the cells and the structure of spongy parenchyma basically differed from the field-grown plants. In the case of Sorbus rotundifolia similar anatomical differences were found both in vitro and in vivo as in the case of Prunus x davidopersica `Piroska'.

  • Influence of different growth regulators on the in vitro morphogenesis of an ornamental variety of carnation
    55-57.
    Views:
    130

    Callus formation, as a prerequisite for the induction of somaclonal variability, was achieved successfully with certain molar ratios between 2,4-dichlorophenoxyacetic acid and benzyladenine. Regeneration of new plants from shoot apex meristems could be significantly improved by the combined addition of very low amounts of indolebutiric acid, benzyladenine and gibberelic acid, dissolved in the Murashige-Skoog nutrient medium. These in vitro treatments may contribute to a more efficient micropropagation of the Rimini variety of carnation.

  • Test of the utility of apple retrotransposon insertion patterns for molecular identification of 'Jonathan' somatic mutants
    7-10.
    Views:
    166

    Up until today, apple sport mutants proved to be indistinguishable from each other and their progenitors at the molecular level using random amplified polymorphic DNA (RAPD), amplified fragment length polymorphism (AFLP) and simple sequence repeat (SSR) marker techniques. This is not surprising, since the genomes of these somatic mutants differ only in one or a few small regions that affect economically important characteristics, such as improved fruit colour, size, or flavour. In most cases, these genome differences are probably caused by retrotransposons which are able to convert their RNA transcripts to DNA with reverse transcriptase enzyme prior to reinsertion, but unable to leave the genome and infect other cells. Retrotransposon insertions can alter the expression of other genes and/or the structure of encoded proteins. The sequence-specific amplified polymorphism (S-SAP) technique is capable of revealing the genetic distribution of retrotransposable elements over the whole genome. The present study used this approach to try to characterize and distinguish 'Jonathan' somatic mutants via fingerprinting, which is an unsolved problem.

  • Identification of plant taxons by isoelectric focusing
    65-67.
    Views:
    152

    Differences were demonstrated in esterasei coenzyme pattern of some essential oil producing plants belonging to the Apiaceae family — fennel (Foeniculum vulgare Mill.), angelica (Angelica archangelica L.), lovage (Levisticum officinale Koch.), dill (Anethum graveolens L.), coriander (Coriandrum sativum L.), anise (Pimpinella anisum L.), caraway (Carum carvi L.) — as well as differences between two varieties of fennel seed by using isoelectric focusing. That method provides quality control in essential oil plants and is suitable to describe isoenzyme pattern characteristic for taxons.

    Based on our findings, isoelectric focusing seems to be suitable for identification and differentiation of different plant samples, providing an easy tool for further processing as well as for breeding.

    Our further aim is to apply that method to differentiate among samples belonging to the same species according to their value of inner content.

     

  • The hungarian raspberry today and outlooks of its development (Review)
    7-11.
    Views:
    130

    The hungarian raspberry today and outlooks of its development (Review)

  • Molecular identification of old Hungarian apple varieties
    37-42.
    Views:
    237

    Altogether 40, mainly old Hungarian apple varieties were screened with six previously described microsatellite markers. A total of 71 polymorphic alleles were detected (average 11.8 alleles/locus) and the heterozygosity of markers averaged very high (0.8). The genetic variability among the genotypes proved to be so remarkable that as few as three markers from the applied six were enough to distinguish between the 40 varieties. This was also confirmed by the cumulative probability of obtaining identical allele patterns for two randomly chosen apple genotypes for all loci, which value was quite low: 2.53 x 10-5. The molecular identification of these genetically very different old apple genotypes could be very useful in future breeding programs.

  • The effects of ACS (1-aminocyclopropane-l-carboxylate synthase) gene down regulation on ethylene production and fruit softening in transgenic apple
    65-70.
    Views:
    109

    A detailed examination of the production of ethylene and other ripening parameters during storage period has been undertaken in transgenic apple fruits, where the ethylene biosynthesis was inhibited by antisense ACS (l-aminocyclopropane-l-carboxylate synthase) gene. Data indicate down regulation of ethylene production, softening and spoilage in some transgenic lines. In some cases ethylene production was inhibited for over 90 percent, considerable reduction of softening and spoilage was observed probably due to the reduced activity of cell wall degradable enzymes. ACS activity was also monitored during ripening. The fruits of the best transgenic lines could be stored for minimum 4-5 months longer under 5 °C cold room storage conditions and one month longer at normal room temperature. This molecular approach can provide an alternative way to replace the commonly used and costly atmospheric storage of fruits.

  • Production of transgenic carnation with a heterologous 6-phosphofructo-2-kinase/fructose 2,6-bisphosphatase bifunctional enzyme cDNA
    75-79.
    Views:
    108

    Transgenic carnations were produced with a modified mammalian bifunctional enzyme cDNA coding 6-phosphofructo-2- kinaseffructose 2,6-bisphosphatase. Relative activity of this enzyme determines the fructose 2,6-bisphosphate (fru 2,6-P2) cytosolic concentration. This metabolite — as a signal molecule — is one of the carbohydrate metabolism regulators. The regenerated Dianthus chinensis and Dianthus caryophyllus shoots were selected on MS basal medium containing 150 mg/1 kanamycin. Transgene integration was proven by PCR analysis with cDNA specific primers followed by Southern hybridization of DNA isolated from selected green shoots, which survived on kanamycin containing medium, so 3 D. chinensis and 20 D. caryophyllus transgenic plants were produced. Transgene expression were examined by RT-PCR. Transformed and control plants were potted in glasshouse to evaluate the effect of modified fru 2,6-P2 on development, growth and carbohydrate metabolism.

  • Molecular analysis of strawberry cultivars using RAPD, AP-PCR and STS markers
    24-28.
    Views:
    117

    Seventeen strawberry (Fragaria x ananassa Duch.) cultivars representing the national list of Hungary, were subjected to RAPD, AP—PCR and STS analysis. Of the 31 decamer and oligomer primers tested 26 primers produced polymorphic patterns. 45 polymorphic fragments were analysed, ranging between 200-2800 by in size. Based on the data, similarity coefficients (Jaccard index and Simple matching coefficient) were calculated, and dendrograms were constructed using the unweighted pair group method of arithmetic averages (UPGMA). The dendrograms only partly reflect the known pedigree data. Specific RAPD markers were identified for cultivars F5, Pocahontas and Rabunda.

  • Identification of ripening-related genes in strawberry fruit by cDNA-AFLP
    33-41.
    Views:
    145

    An RNA fingerprinting study of strawberry receptacle and achene tissue was performed to identify candidate genes involved in fruit ripening. Quantitative cDNA-AFLP was used to detect differential gene expression in green, white, pink and red stages of fruit ripening. Based on hierarchical average linkage clustering the differentially expressed genes formed three major groups, genes expressed only in green receptacle, genes expressed mainly in white, pink and red receptacle, and in achene. 130 transcript-derived fragments (TDFs) were isolated and sequenced. Most TDFs did not show any homology to sequences with known functions, others were homologous to genes involved in oxidative stress response, signal transduction, regulation of development and cell-wall metabolism. Novel genes, so far not associated with strawberry ripening and ripening in general, were identified, such as genes encoding a bHLH protein, putative nitrilase-related protein, putative HD-zip protein. The differential pattern of gene expression draws the attention to the significance of ripening induced-or repressed promoters in strawberry fruit, whose isolation and characterization can be useful tool for functional genomics. For this purpose nine cDNA-AFLP fragments related either to ontogeny or senescing were completed with 5'UTR aiming at more precise annotation and future promoter isolation. Although tens of potentially important transcriptome changes were identified, the function of many ripening induced genes remain unknown.

  • Possibility of stevia (Stevia rebaudiana B.) production in Hungary
    29-32.
    Views:
    259

    Artificial sweeteners have harmful effect on human health, so it is great interested in stevia extract. Our experiment was aimed to show the possibility of inland production of stevia. Different plastic mulches were used (black and white) on raised bed and were compared to uncovered (control) plots for yield and state of health of plants. Furthermore we evaluated the depth of cuttings (low cutting until the 6th double leaf; normal cutting until the upper ⅓ of the plant) on the yield depending on the covering method. The plants were  transplanted on 9 of May, 2014 on raised bed, 3 rows on it, with 33x25 cm spacing. According to our results, the black plastic mulch produced the highest yield, which can be explained by suppressing effect on weeds, furthermore it kept the soil warm, moist and protected the lower leaves from soil wetness. But, the white sheet mulch could not eliminate weeds around the plants. The total biomass on the black plastic sheet covered plots was the highest, nearly 1000 g pro plant by low cutting. On the control plots the fungi infection reached about 25-30%, which caused leaf falling of plants, decreasing of yield by the end of vegetation period. To summarise, stevia production is possible in Hungary, but it is important to pay attention to the balanced soil moisture and low humidity in the leaf area. It is suggested to cover the soil with plastic sheet or organic materials, such as bark and chippings.

  • Investigation of the in vitro regeneration of mericlones in the caribe variety of carnation
    87-89.
    Views:
    123

    In vitro culture conditions were experimented for the relatively sensitive, but very esthaetic "Caribe" variety of carnation with uniformly dark violet flowers. Regeneration of new plants from shoot apex meristems can be significantly improved by the combined addition of very low amounts of indolebutiric acid, benzyladenine and gibberelic acid, dissolved in the Murashige-Skoog nutrient medium. Callus formation as a prerequisite for the induction of somaclonal variability can be achieved successfully with certain molar ratios between 2,4-dichlorophenoxyacetic acid and benzyladenine. Acclimation of the obtained mericlones to the ex vitro conditions was also evaluated.

     

  • Effects of aromatic cytokinins on structural characteristics of leaves and their post- effects on subsequent shoot regeneration from in vitro apple leaves of 'Royal Gala'
    41-46.
    Views:
    153

    The effects of different aromatic cytokinins applied in different concentrations and combinations were investigated on the histology of in vitro apple leaves and their post-effects on subsequent shoot regeneration from these leaves were studied. Great differences in the anatomical structure of leaves could be detected originating from media containing different types and concentrations of aromatic cytokinins. The number of regenerated shoots per explant and the organogenetic index were used for the evaluation of the post-effect of aromatic cytokinins on shoot regeneration. The histological structure of leaves used for regeneration and their regeneration response showed a good correlation. When the pre-treatment caused a juvenile-like or less-differentiated structure, the number of regenerated shoots per explant increased and often vitrification also decreased and consequently the organogenetic index also increased. A strong interaction between cytokinin-content (type and concentration) of the pre-treatment medium and that of the regeneration medium could also be detected.

  • Some physical properties of apricots and testing apricot sorting machines
    51-62.
    Views:
    212

    Examinations were carried out in the manipulating and packaging plant of Gyümölcsért Ltd, in Boldogkôváralja, to determine some physical properties of five apricot cultivars and to test the work quality of the apricot sorting machines. The size and the weight of the fruits were measured and two sorting machines were tested. The results are given in tables and diagrams. The conclusions are also summarised.