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  • The impact of various grape stock cultivars on the As, Cu, Co and Zn content of the grape berry (must, seed)
    39-44
    Views:
    133

    Scientific research from the last decades showed that the inappropriate industrial and agricultural production caused an abnormal increase of the potentially toxic elements in the soil. Unfortunately the acidification of the soil is an increasing problem in Hungary. According to Várallyay et al. (2008) 13% of the Hungarian soils are highly acid. Accumulation of toxic elements differs in the genetically diverse plant species. The root of the plant constitutes a filter so that the rootstock is also kind of a filter system, which may prevent that the scion part (such as berry) accumulate high levels of various potentially toxic elements from the soil. The aim of research was to determine how different grape rootstocks influence the As, Co, Cu and Zn content of the musts and seeds. Thus, specifying which of the grape rootstocks takes up the lowest level of these 4 elements (As, Co, Cu and Zn), and accumulates in berries, so could reduce the potentially toxic element load of the grape berries. The grape rootstock collection of the University of Debrecen was set up in 2003 in 3x1 m spacing on immune sandy soil. Grafting of ‘Cserszegi fűszeres’ was started in 2010. We could evaluate yields harvested from 12 rootstock varieties of the experiment in October 2011. We obtained valuable differences in the arsenic, copper, cobalt and zinc concentrations of musts and seeds of ‘Cserszegi fűszeres’ grafted into different rootstocks. The results obtained from the 2011 harvest support the statement that the choice of rootstock might be an important factor to increase food safety. The differences in concentration of the four elements observed in case of the rootstock may have been caused on one hand by the rootstock effect, and on the other hand, the vintage effect has a very significant impact on the vines element uptake. Several years of experimental results will be needed to answer these questions.

  • Definition antioxidant activity of selenium-enriched food sprout, as well as their microbiological analysis
    25-30
    Views:
    179

    In this present study, we prepared selenium-enriched food sprouts, where the antioxidant capacity was analysed, we also determined their microbiological status. We took into account the fact, we choose micronutrients to our treatment, that selenium can be delivered to the body by a small amount with the most widely consumed food.

    We focused during our research to determine that the increasing concentrations of selenium treatment, in which we used sprouts, knowing fully well that it has an impact on aboriginal antioxidant capacity of sprouts, which is mainly due to high vitamin content of sprouts.

    Furthermore, we think it is important to make microbiological analysis, because germination conditions, for example temperature, pH, all this will create an ideal environment for the growth of microorganisms. So we had goal to determine, how the used selenium concentration affect the total plate count, coliform bacteria count and Staphylococcus aureus count of sprouts.

    We determined the aboriginal water-soluble and lipid-soluble antioxidant capacity of sprout with the PHOTOCHEM chemiluminometer and we applied pour plate technique for the mapping of the mycrobiological state of sprouts.

    Experimental results are evaluated, we state that increasing concentrations of selenite or selenate treatment, is primarily water-soluble antioxidant capacity of sprouts was affected. The water-soluble antioxidant capacity of wheat sprout was much higher than the measured values in pea sprout, this may be linked to what we measured. That is much higher ascorbic acid content in case of wheat sprout, which is well known as one of the most important antioxidant properties compounds of wheat sprout.

    We conclude from the results of the microbiological, that the highest concentrations of selenite or selenate treatment has a relative significant anti-microbial effect in case of wheat sprouts. Coliform and total plate count showed no clear decreasing tendency, although the values of treatments in both cases obtained were below the control values.

  • Pathogenicity differences between group I and group II of Botrytis cinerea
    81-85
    Views:
    95

    Botrytis cinerea has been reported as a species complex containing two cryptic species, groups I (Botrytis pseudocinerea) and II (B. cinerea sensu stricto). In order to compare the pathogenicity of group I and group II of B. cinerea, we have selected 4 strains of group I and 4 strains of group II. The results demonstrated that competitive infection of group II was more on grape, cucumber and paprika leaves, than group I. However the results on bean leaves did not correlate the applied B. cinerea group.

  • Q-PCR analysis of the resistance of Hungarian Botrytis cinerea isolates toward azoxystrobin
    41-44
    Views:
    76

    The genes being in the mitochondrial DNA primarily encode the enzymes of cellular respiration. Fungicides belonging to the family of quinol oxidase inhibitors (QoIs) play on important role in the protection against several plant diseases caused by fungi. These fungicides bind to the cytochrome bc1 complex so they block electron transport between cytochrome b and cytochrome c1. This way these fungicides inhibit the ATP synthesis consequently they inhibit the mitochondrial respiration. The QoI resistance has two mechanisms. One of them is the point mutation of the cytochrome b gene (CYTB), e.g. the substitution of a single glycine by alanine at position 143 results in high-resistance. The other is the cyanide-resistant alternative respiration sustained by the alternative oxidase.
    In a cell there are several mitochondria. The phenomenon when the genomes of all mitochondria in the cell are identical is called homoplazmy. If in the cell there is wild and mutant mitochondrial DNA this is called heteroplasmy. Whether the mutation in the mitochondria causes fenotypical diversity or does not depend on the dose, i.e. it depends on the percentage of the changed mitochondrials. During our work we investigated Botrytis cinerea single spore isolates which have been collected in 2008-2009 on different host plants. Our goal was to decide whether heteroplasmy influences the level of resistance. We managed to detect the change of the level of heteroplasmy, so the change the level of the resistance due to the treatment with fungicide.

  • Cytochrome b diversity of Hungarian Botrytis cinerea strains
    18-21
    Views:
    90

    In the mitochondrion of eukaryotes, cytochrome b is a component of respiratory chain complex III. Cytochrome b is encoded by the
    cytochrome b (CYTB) gene located in the mitochondrial genome. The fungicidal activity of QoIs relies on their ability to inhibit mitochondrial respiration by binding at the so-called Qo site (the outer quinol-oxidation site) of the complex III. Since their introduction, QoIs (like azoxystrobin) have become essential components of plant disease control programs because of their wide-ranging efficacy against many agriculturally important fungal diseases like grey mould on various crops. QoI resistance primarily arises from a target-site-based mechanism involving mutations in the mitochondrial CYTB. As the management of grey mould is often dependent on chemicals, the rational design of control programs requires the information about the diversity of genes connected with resistance in field populations of the pathogen.
    Monospore B. cinerea field isolates has been collected during 2008-2009 from different hosts in Hungary. PCR fragment length analysis
    indicated the high frequency presence of type large intron in the isolates while in a few strains G143A substitution could also be detected.
    These results indicated the heterogeneity of CYTB in the Hungarian B. cinerea populations, which possibly involve the heteroplasmy of this
    mitochondrial gene, moreover indicates the existence op azoxystrobin resistant populations in Hungary.
    This work was supported by NKFP-A2-2006/0017 grant. Erzsébet Fekete is a grantee of the János Bolyai Scholarship (BO/00519/09/8).