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  • Detection and identification of phytoplasmas in peach based on woody indexing and molecular methods
    35-41.
    Views:
    137

    Symptoms resembling phytoplasma disease have been observed on peach trees in a seed-source plantation of stone fruits in south Hungary quite recently. In this publication we report on the results of woody indexing of symptomatic peach trees on GF 305 indicator in the field and under greenhouse conditions as well as on molecular studies. Phytoplasma infection detected on GF 305 indicators in greenhouse and field indexing was confirmed by PCR. Nested PCR was conducted using universal primer pairs followed by group and subgroup specific primers for the second amplification. RFLP analysis of nested PCR products was performed using Rsal restriction enzyme. Based on the results of molecular studies it can be concluded that phytoplasmas, belonging to the European stone fruit yellows subgroup (16SrX-B) were identified in peach trees. Further studies on symptomatic peach trees originating from different parts of Hungary are in progress.

  • Vegetative and micropropagation potential of Piper guineense (Schumach and Thonn)
    29-36
    Views:
    112

    The continuous loss of forest plants due to deforestation, and the increasing demand for Piper guineense because of its medicinal and food value, has put a permanent pressure on its population in the wild where it is collected. A method for conservation and mass propagation is therefore required. This research was undertaken to determine the optimal concentration of auxin needed for vegetative propagation and to investigate the potential of Piper guineense for micropropagation. The auxin optimization study of vegetative propagation was based on the use of two-nodal stem cuttings treated with five different concentrations of indole-butyric acid (IBA). Growth parameters such as the number of sprouted, rooted and survived cuttings among others were determined. To investigate the potential of Piper guineense for micropropagation, nodal explants were subjected to different sterilizing treatments using ethanol, NaOCl, mancozeb, streptomycin and Plant Preservative Mixture (PPM). The effect of plant growth regulators (PGRs) was tested on sterilized nodal explants using full strength Murashige and Skoog (MS) hormone-free media alone as control and MS media supplemented with PGRs (BA, NAA and KIN) at different concentrations and combinations. Significant differences were observed across the treatments for all growth parameters measured. However, 2000 ppm IBA significantly (p<0.05) influenced sprouting and rooting of the stem cuttings. Piper guineense explants have deep tissue contaminants, which cannot be eradicated by surface sterilization alone except double sterilization using PPM. On control media, neither shoot nor root response was observed while the highest percentage of induced roots was obtained from explants cultured on MS +1 mg/L BA + 0.25 mg/L NAA. Shoot induction was only achieved when BA was used alone and when subcultured on media supplemented with NAA, which generated roots.

  • Fire blight in Hungary between 1996 and 2003
    67-70.
    Views:
    109

    Shoot blight of pome fruits caused by Erwinia amylovora, i.e. fire blight, is present in numerous countries of Europe. The disease must have entered into Hungary in the middle of the 1990's and it was first noted and, respectively, identified in 1996 (Bacs-Kiskun county). The losses caused by the pathogen appeared — in orchards and scattered sites of production — in four counties, namely Bacs-Kiskun, Baranya, Bekes and Csongrad at the beginning. From June 1996, a process of eliminating infected parts started in the course of a large action performed under the control of the Department of Plant Protection and Agro-Environmental Economy of the Ministry of Agriculture, under the direction of the plant protection inspectors of the then existing Stations of Plant Health and Soil Conservation. The 'operation' against the disease commenced by cutting back out the infected parts of the canopy and, grubbing them out, respectively. As for the spread of the pathogen (1996-1998) it could be observed that the disease entered into Hungary from the south, south-east and then it also spread into the middle part of the country. As a result of adequate official action and efforts as well as of adequate chemical and antibiotic treatments, moreover because of the introduction of more modern technologies of plant cultivation and those of plant protection it can be reported on that the pathogen hardly appears or does not occur at all on the northern, north-western part of the country. The infection also appears mainly on the parts east of the Danube. Cultivars less susceptible or non-susceptible to the disease are planted in recently established orchards what is also a considerable factor in respect of preventing spread of the pathogen.

  • The Hungarian pear germplasm as source of genetic variability for breeding programmes
    7-13.
    Views:
    203

    TheHungarian pear collection (Pyrus communis L.) consists of 423 genotypes distributed over seven genebanks inHungary. This is one of themost extensive collections of native and cultivated pears found in Eastern Europe and includes a wide range of genotypes with small size fruit (referred to as “Miniature pears”). Based on the in situ and ex situ measures taken by governmental and other institutions for fruit tree conservation in Hungary, an overview is given on some activities regarding areas of Pyrus collection and genebanks where pears are collected and grown. Descriptions of traits of miniature pears found in Hungarian genebanks for the interest of genetic characterization and breeding are presented.

  • Mulching in grape plantations
    25-31.
    Views:
    141

    In continuous studies regarding the conservation of the advantageous condition of the soil structure, the highland plantations that are surrounded by living waters have major importance where the erosion of the soil, nutrients and chemicals endangers the quality of the water and the living world of the waters. At the same time the extreme weather and dry summers of the past years have made it important to look for soil cultivation solutions and technologies that are capable of decreasing the evaporation of the soil, for enhanced conservation of soil moisture and to improve the soil structure that is required for the growth of healthy roots. In our experiment we have studied soil mulching with organic plant residue, by sods and the effect of the mechanical cultivation on the soil and on the grape through two growing seasons. From the studied treatments, the mulching with organic plant wastage showed the most efficient results from the point of view of the nutrient distribution in the grape and yield. It also had a positive effect on the soil structure and humidity.

  • Traditional farming within the Carpathian basin - pomaceous fruits
    15-18.
    Views:
    162

    In the Carpathian basin there are still maintained the main historical fruit varieties and traces of traditional farming. The Department of Fruit Science considered the utilisation of obsolete varieties in breeding as source of resistance to local adversities, moreover, the practice of traditional .farming using those varieties should be also explored. In the present study, the farming methods and variety structure of two substantially different growing sites are described. One is an alluvial plain along a river were an ancient form of farming based on the control of sluices. The second is practised by clearing the forest on the slopes of the central range and of the Carpathian chain. During the course of our research we succeeded to find 8 pear, 29 apple and a few quince as well as medlar varieties. Further endeavour would be the conservation of those varieties, preferably on the spot together with their growing techniques as relicts, also as aesthetic components of that particular landscape. Our committed partners in this work are the National Parks.

  • Importance of orchard floor management in organic fruit growing (nutritional aspects)
    61-67.
    Views:
    274

    Worldwide research goals and concerns are to soil conservation and improve. This conception is mostly actual in horticulture where the numbers of high-density plantings are continuously increasing. High-density orchards cause more intensive nutrient and water uptake. So that the preservation of soil moisture and nutrient level are key factors in qualified fruit growing. On the other hand due to the climatic changes the water supply of trees will be satisfied among worse conditions than some decades ago. Appearance of water supply problems and water stress is increased in organic growing, where the number of corrections is limited anyway. Furthermore, floor management is a successful tool in weed management which causes many problems for organic growers due to the prohibition of synthetic herbicides. This paper will mainly focus on the nutritional aspects of methods of orchard floor management for growers adopting organic fruit management to make their production profitable.

  • Certification programme for production of virus-free propagating material of grapevine and its results in Hungary
    39-43.
    Views:
    139

    In Hungary, detection of virus and virus-like diseases of grapevine began in 1960's at the Research Institute for Viticulture and Enology by János Lehoczky and his colleagues. At present, sixteen virus and virus-like diseases of Vitis vinifera are known to occur in Hungary.

    Regular virological screening of grapevine varieties started in 1972. The present system of screening (visual selection, indexing, ELISA) has been established using methods with continuous improvement according to recommendations of international organizations.

    In the first year symptomless grapevine plants are selected and marked during surveys carried out twice in the vegetation period: at about flowering and in the second half of September. At the first selection time plants are sampled for ELISA.

    In the spring of the second year, overwintered canes are checked by woody indexing on 8 indicator species in the field.

    In the third and fourth years the nursery is evaluated twice again. At the end, the marked grapevine plants, giving negative results on all indicators in every case, are considered virus-free.

    In autumn of the fourth year, the virus-free material is planted out under screenhouse and also in a special mother block (nuclear stock) for maintenance and propagation.

    Mother blocks of virus-free scion varieties have been established on 2 ha and those of rootstock varieties on 0.5 ha planted with the following number of varieties included in the national list: 71 European scion — and 12 rootstock varieties or variety candidates/clones. It is necessary to increase the area of Pre-base, Base and Certified stocks exclusively with tested virus-free (clean) material.

  • Studies on some seed traits of Iris pumila L., Adonis vernalis L., Primula veris Huds. and Alkanna tinctoria (L.) Tausch.
    36-40.
    Views:
    125

    In this study we summarize the results of a five-years period concerning seed traits examinations on Iris pumila, Adonis vernalis, Primula veris and Alkanna tinctoria, with special attention to seed dimensions, seed mass and other traits concerning plant fitness, to their variability and the relationship among them. We found tight correlation between seed weight and seed dimensions in Adonis and Primula, at the same time no correlation exists among the same characters in Alkanna tinctoria. Consequently, the seed weight and seed dimensions can be used as synonyms in the form of „seed size" only after preliminary detection of correlations among them.

    The variability of seed traits is higher in natural categories (individuals, morphs) than in seed mass categories as speculative groups. When we need homogeneous plant stand (e.g. for an introduction experiment) it is suggested to use seeds pre-selected in this way. For ex situ conservation, where the central goal is to maintain the genetic variability, seeds originated from different individuals are preferred.

     

  • The importance of Hungarian melon (Cucumis melo L.) landraces, local types and old varieties (Review)
    83-87.
    Views:
    143

    While supermarkets devote whole aisles to hybrids, traditional varieties are hard to find, and becoming scarcer day by day. Unfortunately, countless old melon varieties have already been lost. Luckily we succeded in collecting most of these varieties, and thus conserving them in Gene Banks. Landraces, local types, and old breed races show many characteristics that could be useful in organic farming. It is important to get acquainted with these varieties and cultivars, because they have greatly adapted to the climatic and pedological conditions of the Carpathian basin. Therefore their conservation is essential for the protection of Hungarian genetic variability. With the help of utilising our landraces in organic farming; careful selection; and the usage of marketing strategy in order to enhance quality features, such as unique flavour; we could reclaim the one-time excellent reputation of Hungarian melon.

  • The role and current state of gene reservation of medicinal and aromatic plants in Hungary an overview
    19-21.
    Views:
    147

    As it well known the decrease of biodiversity is a large problem all over the world. In case of medicinal plants, where the huge majority of drugs are collected from natural ecosystems, the sustainable, utilization of the populations and reservation of their gene-pools has an increased interest.

    In Hungary, the major background of 'in situ' reservation of medicinal plant species, their natural plant associations and ecosystems is the official protection by law. Successful examples are known for the controlled utilization of medicinal and aromatic plant species grown in protected areas. Assuring the naturally occuring high degree of biological and chemical diversity of species is a special task in this field: only maintenance of valuable intraspecific races can form the real genetic basis of natural biologically active compounds.

    Maintenance of chemotaxonomical gardens and gene bank collections (seed banks, tissue banks) as 'ex situ' methods of reservation is carried out on an extended range in Hungary. As the required information on storage and maintenance of many medicinal and aromatic plant species is yet missing, exhaustive research is carried out at both genebanks in Hungary, which are specialized for medicinal plant reservation (RIMAP- Budakalász, SZIU- Budapest).

    Beside the static conservation methods, 'quasi-production systems' are intended to assure an up-to-date and economically possible way of dynamic reservation with sustainable utilization.

     

  • Mechanical behavior of catching surfaces used for fruit harvesting
    59-64.
    Views:
    104

    Various fruit gathering devices are important part of tree shakers used in fruit harvesting. The catching surface is generally used in the form of a stretched thin sheet interacting with the falling fruit. This interaction depends on many factors such as the shape and mass of the fruit, the falling height and the mechanical properties of the catching material.

    In recent investigation different canvas, composite and silk materials were selected and their mechanical behavior was experimentally determined. Using the energy conservation principle, the main impact characteristics of the falling fruit was derived and used. Static and dynamic loading tests were carried out using spherical intenders and artificial fruits. Investigations have shown that, using the appropriate material characteristics, the catching surface can serve as a cushioning material and it can considerably reduce the impact stresses in the falling fruits.