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  • Young-making of sour cherry cultivars and examination of their regenerative characteristics
    102-105
    Views:
    85

    Although a high portion of domestic orchards is cultivated extensively, quality Hungarian sour cherry is a highly demanded product throughout Europe. Trees are slightly pruned, or not pruned at all. Thanks to the unique character of the species, older wood parts are pilling up. Thus, the interior of the canopy is inactive, fruits and shoots confine the exterior layer of the canopy.
    We established pruning treatments in the sour cherry plantation in the Horticultural Exhibition Garden of the University of Debrecen, involving two age groups in two spacings. The trees are standing on seedling rootstock. The involved varieties were: Érdi bőtermő, Debreceni bőtermő and Kántorjánosi. We examined how to encourage shoot formation and the regeneration of older, pilling wood of the interior canopy parts.
    Applying strong rejuvenating cuts, the most shoots were generated on the 3rd and 4th year laterals. Wood parts older than the 3rd year shall be removed by leaving short (2-3cm) stubs. This way, older, passive woodparts can also be made to burst out. From the examined varieties the Kántorjánosi showed the most favourable regenerative ability. Due to summer pruning, more shoots regenerated on the axis of the trees, than on those rejuvenated in the dormant season.

  • Comparison of apricot cultivars for suitability for organic growing
    63-65
    Views:
    60

    Nowadays, important task is using more widely the environmentally friendly production technologies. There are considerable differences
    among technologies using reduced spray programs (integrated and organic) in plant protection and plant nutrition.
    In this case integrated production has a better position as roles for organic production more strict and due to this fruits has an obvious
    temporal and permanent reduction in tree conditions. Fitotechnical elements and renewal and regeneration of cultivars are important
    factors for offseting or delaying of condition weakening.
    In this study, 5 apricot cultivars (not pruned for 8 years) were compared in their characteristics (assessment of inactive, semi-active and
    active plant parts).
    Our study showed that there were 50-70% differences among observed characteristics. Our study confirmed those cultivars which are
    suitable for organic production and which one more resistant to condition weakening and which one able to tolerate negative technological
    effects.

  • Development of a New Maize (Zea mays L.) Breeding Program
    25-30
    Views:
    91

    Genetic manipulation may not replace any conventional method in crop breeding programs, but it can be an important adjunct to them. Plant regeneration via tissue culture is becoming increasingly more common in monocots such as corn (Zea mays L.). In vitro culturability and regeneration ability of corn decreased as homozigosity increased, which suggested that these two attributes were controlled primarily by dominant gene action. Pollen (gametophytic) selection for resistance to aflatoxin in corn can greatly facilitate recurrent selection and screening of germplasm for resistance at a much less cost and shorter time than field testing. Integration of in vivo and in vitro techniques in maize breeding program has been developed to obtain desirable agronomic attributes, speed up the breeding process and enhance the genes responsible for them. The efficiency of anther and tissue cultures in most cereals such as maize and wheat have reached the stage where it can be used in breeding programs to some extent and many new cultivars produced by genetic manipulation have now reached the market.

  • Correlation of pruning time and fruiting part differentiation of sweet cherry cultivars
    131-134
    Views:
    66

    There are several extended studies in sweet cherry production in Hungary and all over the world i.e. for creation and maintainence of smaller tree crown and high density orchards. The use of suitable dwarf rootstocks for this fruit species are very limited. On one hand, most of the draf rootstocks do not cause enough growth reduction and on the other hand these rootstocks are get old very quikcly and their fruits become small, and therefore, they not serve the requirements for intensification. In summary, there is a need for those rootstock which are vital, regeneration enhanching and delay ageing. Due to ensuring above features, Prunus mahaleb is still an obvious solution for intesive production. Increasing intensification can be obtained by use of modernisation of technological elements and suitable cultivar choice. 
    According to this increasement of intensity through application of novel technological elements (timing, manner and severity of pruning) and selection of the proper cultivar is implement able. Important differences are experienced between sweet cherry cultivars in their growth attributes, light demand and dynamics of fall back in regenerative potencial of different aged wood parts. From this point knowledge of the abow detailed is very important in order to maintain rentability of already established plantations. Our work shows the formation of production part in
    9-year old plantation with spike spindle and free spindle crown forms depending on pruning timing (winter, summer) and determining of their various effects. 

  • Overview of the evolutionary history and the role in citric acid production of alternative oxidase
    83-88
    Views:
    125

    All organisms are exposed to countless environmental effects, which influence in a disadvantageous way their life processes. They continuously adapt to the changing conditions and respond to the stress impacts by defence mechanisms. Through different signal transduction pathways they are able to increase or decrease the expression of their genes and consequently modify their metabolic processes. My interest focuses on alternative oxidase (AOX) enzyme whose expression is often increased under biotic and abiotic stress. The so far proven and putative functions of the AOX play a role in the ability of organisms to adapt to different conditions, such as heavy metals accumulation, pathogenic infection, oxidative stress and lack of oxygen or nutrients.

    AOX is a member of the di-iron carboxylate protein family. Members of the di-iron carboxylate protein family are present in all kingdoms of life. They are considered to have ancient origin. It is believed that their sulfide-resistant and oxygen-reducing ability played a role in the survival of organisms during the transition between the anaerobic and the aerobic world. It is assumed that the AOX arose in eukaryotes through a primary endosymbiotic event, and this event made possible the development of mitochondria. Afterwords, vertical inheritance, and secondary and tertiary endosimbiotic events led to its spread among eukaryotes. It is assumed that bacteria obtained AOX by horizontal gene transfer from plants.

    AOX-catalyzed alternative respiration plays an important role in the operation of energy-producing and biosynthesizing system of microorganisms. In these cases, the regeneration of reduced cofactors is an essential condition, and therefore may be rate-limiting for biotechnological processes, including the citric acid production.

  • Angle-count sampling method for estimating forest stand volume – a practical approach
    99-102
    Views:
    143

    Point sampling, which is also known as angle-count sampling (ACS), can be considered an efficient way of estimating the basal area and volume of forest stands. It is possible to use it in forest management: providing more accurate estimates (precision <10%) of  site and stand characteristics needed for management planning. 20 black locust (Robinina pseudoacacia L.) stands were selected at final cutting age to determine the regeneration criteria based on their total volume. It was verified that at P=5% there was no difference between the main volume values of stands indicated in the relevant forest plans as well as calculated by the ACS method.

     

  • Physiological plasticity of main tree species of lowland hornbeamoak forest as a results of forest gap regeneration
    99-103
    Views:
    161

    Specific leaf area (SLA) of English oak (Quercus robur L.) and hornbeam (Carpinus betulus L.) as members of Querco robori-Carpinetum were investigated in two different habitat in terms of gap forest management: in the gap and in the inert forest. The artificial opening process of the forest resulted in more light for growing saplings and need for acclimatization. Photosynthesis is one of the most important ways for plant life and plant production basically influenced by altered light condition resulted in opening process. Efficient photosynthesis is important for plant life, plant production, but species-dependent plasticity of photosynthesis makes one species more tolerant, than others. The specific leaf area is acceptable parameters for characterising plant production, dry matter content and leaf structure. The dry matter content based on known leaf area is higher in oak both sun and shade leaves, than hornbeam. The different place of leaves in the canopy of trees did not influence the values of SLA.

  • Tending operation model for red oak stands
    133-136
    Views:
    158

    Red oak (Quercus rubra L.) is our most important exotic oak species, that possesses growing culture with almost one hundred years in our country. Plantation character of red oak growing predominates principally by applied regeneration method (mostly artificial), regular planting space, applying defined method and planting space regulation system. Forest tending model for red oak, that considered stopgap in the native literature is intended to serving the latter. Especially important equation in the viewpoint of stand growing, that describes relationship of stem number (N, in hectare) and diameter at breast height (D1.3 in cm) is: N=e9.80220-1.12607lnD1.3.

  • Agrobotanical Analysis of Bean (Phaseolus vulgaris L.) Equilibrium Populations Suitable for Regional Land Cultivation
    148-152
    Views:
    55

    The local bean landraces maintained at small-scale farming level should have importance as complementary source for completion of plant genetic resources with potential role in local land cultivation. Also, they should be used as primary material in breeding activities targeted on improving the foodstuffs quality. In the research were used especially landraces collected in Nyírség, Körös-mellék and Tápióvidék region. Our main objective was to reveal the relationship between the adaptation ability of landraces and the distance from their original collecting place. For that reason the location of the experimental plots was choosen by taking into account that they must be checked in each region, on it’s original region and similarly in other two different regions. On the base of the recorded agro-morphological traits we can get answers on the shaping of adaptation ability, and in the same time by a general chemical characterisation we should know more about the variation of qualitative parameters with a potential economical role. In the designing of experiment a main importance had the conditions where the research is taking place. All activities related to the maintenance of experiment were done in frame of a low input agricultural system to emphasize as much as possible the natural endowments of regeneration places.

  • Possibilities of downsizing sweet cherry trees via growing techniques
    71-74
    Views:
    182

    By applying smaller crown sizes and intensive growing techniques, many advantages can be identified compared to the extensive orchards. Also, nursing/pruning and harvest work can be performed more effectively. The outer and inner quality parameters of the fruit and the effectiveness of plant protection techniques are improved. The smaller crown size enables us to apply technologies for ensuring yield safety (e.g. hail, rain, bird nets), resulting in an increase in productivity. The introduction of smaller trees poses a great challenge to cherry production. Trials with dwarfing rootstocks have not yet been successful, therefore, we must use the cv. Mahaleb rootstock, which is excellently adapted to the Hungarian conditions, and also has a stronger growth. In addition, rootstocks with such strong growth are needed for the necessary regeneration of the productive parts of cherry cultivars, there is a need for. At the research garden of the University of Debrecen in Pallag, we planted 21 cherry cultivars on cv. Mahaleb (CT500) rootstock, in a 4 m x 1 m spacing pattern, in the spring of 2000. In our study, we demonstrated the possibilities of developing and maintaining the string super spindle through repeated summer pruning, in terms of growth, bud and fruit formation,. Based on these parameters, we determined which cultivars are the most suitable for intensive production.