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  • The necessity and possibilities of irrigation in fruit growing under conditions of Hungary
    93-94.
    Views:
    853

    Climatic and soil conditions are highly suitable for most temperate fruit species and promise profitable yields with good quality. An accurate choice of the growing site is, however, decisive because of the wide range agro-climatic variation an soils within the country. One of the most important factors is the annual precipitation which does not exceed, in general, 700 mm. The aims of irrigation practices are, succinctly speaking, the improvement of quantity and security of yields and the guarantee of quality. The relative importance of those criteria changes according to the fruit species. In up to date apple, pear and cherry production, micro-irrigation systems are mainly considered. According to recent experiences, the micro-jet type of water distribution should be preferred to the dripping system. In cherries, the choice of the method is motivated by the need to prevent fruit cracking. Most of the peach and apricot plantations are located on the dry and moderately dry regions of the country. Because of the late freezes, the improvement of security is crucial. There the investment of irrigation systems should concentrate to the possibility of anti-freeze sprays. High water requirements of plums are met in Hungary by irrigation where the method should be decided at the plantation and adapted to the harvesting procedure which could be mechanised or (in high density plantations) picked by hand. Sour cherries are perhaps the less dependent on watering under Hungarian conditions. Yields in small fruits: currents, gooseberries, raspberries and strawberries could be increased by irrigation to 40-50 % and may improve quality too. In those cultures the system of moving flexible wing tubes are considered to be the best irrigation technique.

  • Fruit coloration of apple cultivars
    11-14.
    Views:
    700

    One of the most important parameter of apple cultivars is the scale and the intensity of the coloration of fruits. Nowadays among the bicolour cultivars those are the most saleable which have the highest and darkest fruit coloration. In our three years old study cultivars born with bud mutation and cross breading were examined, which have superior coloration peculiarities than their parental cultivars. According to our results among the observed cultivars the cvs. ’Gala Decarli-Fendeca’, ’Galaval’, ’Wilton’s Red Jonaprince’, ’Early Red One’ and ’Red Cap Valtod’ reached favourable high fruit surface colour (80-100%) regardless the vintage effect. Concerning the colour intensity, that is the darkness of the red colour most of the cultivars (‘Gala Venus Fengal’, ‘Gala Fendeca-Fendeca’, ‘Galaval’, ‘Jeromine’, ‘Red Topaz’, ‘Early Red One’, ‘Crimson Crisp’, ‘Wilton’s Red Jonaprince’) showed excellent values (4,5-5,0). Based on the fruit surface colour and the fruit colour intensity a new index number, the fruit coloration index was created by us, which describes the coloration features in a complex way.

  • Possibilities of brown rot management in organic stone fruit production in Hungary
    87-91.
    Views:
    733

    In this study, possibilities of environmentally-friendly plant protection against two brown rot species was summarized for organic stone fruit orchards. Symtomps of the two most important brown rot species (Monilinia fructigena (Aderh. & Ruhl.) Honey and Monilinia laxa (Aderh. & Ruhl.) Honey) were described and then cultivar susceptibility to brown rot was discussed. Several sustainable plant protection methods were selected and discussed in details such as mechanical, agrotehcnical, biological, and other control possibilities (elemental sulphur, lime sulphur and copper).

  • Production and marketing of medicinal and aromatic plants
    63-75.
    Views:
    345

    The utilisation of medicinal and aromatic plants is growing continuously, which is motivated by both psychological and rational factors. Species belonging to this special group of plants were produced in the territory of Hungary many centuries back. However, the intensification of the production started in the first years of 20 th century, only, and in spite of many political and economical contradictions the medicinal and aromatic plant sector became a successful part of Hungarian Agriculture. Some of the national products had been accepted as a special Hungarian product ("Hungaricum") evaluated as most respectful in the world market. To stabilise, even to develop the production of medicinal and aromatic plants in Hungary the understanding of the actual world situation, especially the forthcoming EU conditions, became essential. Based on the analysis of the situation market and economy of medicinal plant production, a new strategy had to be developed. The medicinal and aromatic plant sector requires a special development program, which should be supported by Hungarian authorities, focusing on the subjects, which are as follows:

    • development of "quasi" EU compatible Hungarian regions specialised for medicinal plant production,
    • development of biological background, technology as well as the quality assurance system of the production,
    • EU compatible regulation and subvention system of the sector, including processing, production and marketing of raw and phytomed ici nes,
    • development of new marketing strategy in both national and international relations.

     

  • Cytokinins affect the stomatal conductance and CO2 exchange of in vitro apple leaves
    25-28.
    Views:
    521

    Effects of different cytokinin supplies including two types of aromatic cytokinins, such as benzyl-adenine, and 3-hydroxybenzyladenine applied at two different concentrations (2.0 and 6.0 μM) were studied on water and gas exchange parameters in in vitro apple leaves of ‘Royal Gala’ and ‘Freedom’ scions after 3 weeks of culture. Cytokinin supply affected the stomatal conductance of water vapour, transpiration rate and the sub-stomatal CO2 concentration of leaves. Effect of cytokinin depended on its applied type and concentration, moreover on the apple scion. According to the results, the rate of CO2 exchange itself is not usable for characterization of function of photosynthetic apparatus of in vitro leaves. However, measurements of stomatal conductance of water vapour and transpiration rate seemed to be good indicators for stomatal behaviour of in vitro apple leaves.

  • Apple allergens as affected by cultivation technolog and variental factors
    91-93.
    Views:
    1222

    Our objective was to study the effect of organic farming and area of cultivation on the allergen content of apple varieties by quantification of the major allergens (Mal d 1 and Mal d 2) using allergen-specific ELISA. The obtained results showed that except Idared IX. 29. most of examined varieties, when cultivated under organic farming conditions, contained lower level of Mal d1 allergen than those produced with integrated farming. The different varieties were found to vary substantially in theirMal d 1 allergen content. Furthermore, with some varieties the area of cultivation affected to some extent the content of Mal d 1 allergen.

  • Interaction of nutrient supply and crop load of apple trees (Malus domestica Borkh.)
    33-35.
    Views:
    319

    Long term fertilisation trials were combined with storage experiments with 'Jonathan' apple trees and fruits to study influence of tree nutrition on quantity and quality of crop. The site of experiments is a typical Carpathian-basin environment with loamy silt soil, high lime content and arid summers. Conclusions has been drown from six years' set of data. Augmented levels of soil fertilisation increased cropping capacity of apple trees, however, the fruit load has not met with cropping capacity in every year. More the def cit came into view in crop load, less the fruit quality resulted in. The deficit in cropping capacity, however, could not have been determined with simple rates as fruit weight per trunk circumference or similar. Better determination was obtained where foliar nutrient contents were correlated to crop per tree figures. In general terms, the N and Ca content in leaves increased with yields when K and P content formulated reciprocally. When storage quality of 'Jonathan' apple fruits were related to crop load (kg/tree), influence of crop deficit became visible. As the crop load and foliar nutrient levels interacted, the fruit quality (number of disordered apples after 6 month of storage) subjected of both physiological phenomena. Higher determination degree were obtained when crop load was assessed together with single or multiple foliar analysis data.

  • Field Vegetable Production in Hungary
    81-84.
    Views:
    435

    Hungary is a country with excellent ecological potentials and with rich traditions in vegetable production. The total vegetable production area comprises about 100 000 ha and annual production amounts to 1.4-1.8 million tons, 75-80% comes from fields and the rest from forcing. Approximately 40 species are produced, but only 20 of them play a dominant role. The most important ones arc: sweet corn, peas, peppers, watermelon, onions, tomatoes, gherkin, carrots, beans, white cabbage.

    40-45% of the total production is processed, 20-30% sold on the fresh market and 30% exported.

    Vegetable production is based on rural farms of 1-5 ha average acreage. It provides living for about 70-100 000 families. The low number of producers' organisations is a major setback.

    Profitability of vegetable production is rather low. Production costs are high, wholesale prices are depressed.

    Vegetables are produced for the industry by contract. Fresh vegetables are sold through local markets (15-20%), the wholesale market (decreasing importance) and direct marketing (35-40%).

    Against the self-sufficiency of the country there is a seasonal import of vegetables mainly in winter and early springtime.

    Hungarian legal regulations are harmonized with the EU directives, EU standards are accepted and applied, traditionally good market connections and cooperation with several EU countries enable the country to be a partner of EU vegetable growers.

  • Vineyards characteristic by using GIS and refl ectance measurements on the Nagy-Eged hill in Hungary
    57-60.
    Views:
    462

    Our investigation was carried out in vineyards on Nagy-Eged hill in Hungary. Grapevine growing plays an important role in Eger Vine Regions. In the grapevine cultivation it becomes necessary to know the requirements of vineyards along the best geographical situation using available cultivation and examination technology to achieve better and quality produce. This study reviews applicability of the different spatial analyst techniques in vineyard especially models based on surface relief and the new technology of hyperspectral analysis. The spectral alteration was examined between different health status and leaves infected by Eriophyes vitis to defi ne spectral characteristics. Thus reflectance measurements could also support to evaluate airborne hyperspectral images with the help of the spectral library.

  • Applicability of 3D laser scanning in precision horticulture
    55-58.
    Views:
    4883

    Due to the technological development, remote sensing instruments and methods have become widespread in all segments of life (from precision agriculture through architecture to medicine). Among the innovative development of remote sensing instruments the 3D laser scanner is of outstanding importance. Horticultural applicability of terrestrial laser scanning technique is a new innovation in the precision agriculture. The structure of trees and branches, the canopy extension, the fruit yield, which can help to recognize some biophysical parameters, can be determined. The examination was carried out with Leica ScanStation C10 terrestrial laser scanner in the Study and Regional Research Farm of the University of Debrecen near Pallag. In this article the measuring principle, the parameters and horticulture applicability of the terrestrial laser scanner are presented.

  • Effect of training system on the incidence of Stigmina carpophila and fruit size and weight of European plum (Prunus domestica)
    78-80.
    Views:
    671

    In a two-year study (2017-2018), the aim was to determine the incidence of shot hole disease (Stigmina carpophila) on plum cultivar ’Čačanska lepotica’ in four different training systems with tree spacings of 4 x 1.5, 4 x 2, 5 x 2.5 and 6 x 3 m. Fruit size (width and length) and fruit weight were also assessed during harvest of fruit in the four training system. Cultivar ’Čačanska lepotica’ was susceptible to shot hole disease and showed shot hole symptoms in both years and in all training systems. In 2017, the highest disease incidence was observed in the 4 x 1.5 m plot (34% in June and 85% at the end of September). In June and July, the 6 x 3 m training system had the lowest disease incidence. In August and September, the 5 x 2.5 m training system had the smallest incidences of the disease among the training systems. In 2018, except for one assessment date (18 August) the 4 x 1.5 m plot had higher incidences than the other three training systems. Training system and years had almost no effect on fruit size, but there were some differences in fruit weight among the training systems.

  • Training and maintaining spindle crowns in cherry production
    51-53.
    Views:
    698

    In cherry production all over the world, intensification of the technology is the main objective of research. Small crowns and high planting densities are aimed to attain high yields per hectare and easier harvesting. Rootstocks of reduced vigour for cherries are more difficult to find than in other fruit species, and the rejuvenation of fruiting structures by pruning is aggravated by the reduced vigour. Intensity of the technology ought to be achieved by a thoughtful application of the technological elements (timing of pruning by various intensity) moreover, by finding different policies for individual varieties. Sweet cherry varieties dominating the assortment proved to be very variable regarding their growing habits. In our experiment, we dealt with the slender spindle and free spindle forms, and how to train the trees to develop and to maintain the desirable form depending on the respective variety in order to achieve the right load of flower buds and yields repeatedly. In this paper, we examine the most important practical issues with the training and maintaining of the crowns of cherries with circular projection and central axis grafted on Prunus mahaleb rootstocks

  • Evaluation of the quality of Sorbus fruits belonging to different species
    37-41.
    Views:
    280

    The interest in wild growing fruits was increased considerably by the pharmaceutical industry, the cosmetics as well as by the food industry. (Stefanovits-Bányai et al., 2004). Elderberry (Sambucus nigra L), sand thorn (Hippophae rhamnoides L.), cornet (Cornus mas L.), dog rose (Rosa canina L. bearing hips) and the Sorbus species (Sorhus ssp.) have been well known medicinal and/or ornamental plants since long. Recently, precious substances have been detected in their fruits, which are indispensable in healthy foods. Several species and micro-species of the genus Sorbus are components of the native flora of Hungary, and the fruit of some of them have been consumed traditionally, however, they are preferably considered as ornamentals. The nursery of Alsótekeres (Balatonvilágos) maintained some 16 clones of Sorbus species, which are mainly apomictic "micro species" of. the collection. In 2003, a comprehensive analysis of sorb fruits born on apomictic micro species was initiated in order to find those, which will be suitable to establish plantations. It turned out that considerable differences exist between the fruits of individual taxa, however, it is largely influenced by seasonal effects. According to physical measurements, a scale of mean fruit masses could be established. As for chemical ingredients of the fruits, those are of special interest, which are involved mainly in anti-oxidant activities of the organisms (calcium, potash, phosphorus, copper, magnesium).

  • Effects of activated charcoal on rooting of in vitro apple (Malus domestics Borkh.) shoots
    98-101.
    Views:
    356

    Rooting of in vitro 'Royal Gala' shoots was studied under different conditions of root induction and root elongation phase. The rooting capacity was affected by both rooting phases. Very high rooting percentage could be reached with both liquid and solid root induction media. Raising the temperature from 22 °C to 26 °C during root induction phase increased the rooting percentage. Presence of activated charcoal in root elongation media can affect the number of roots per rooted shoots and can increase the rooting percentage, the length of roots and the rate of survival depending also on other conditions during rooting. Presence of NAA in root elongation media reduced the number and the length of roots considerably. Favourable effect of activated charcoal on rooting was mainly due to adsorption of NAA.

  • A review of the orchard management in organic fruit production
    43-49.
    Views:
    726

    The elements of orchard management have a determining role in the success of organic fruit production, therefore, it is essential that they are applied properly. The present review gives describes some aspects of the orchard management such as site selection, orchard soil, rootstocks and cultivars, planting materials and plant density, crown shape. Then, one of the most important elements, pruning is discussed with special emphasis on winter pruning, condition and apical dominance, degree and method of pruning, summer pruning. After pruning, an overview of fruit thinning, irrigation, soil cultivation, soil protection (cover plants and mulching) and fertilization is given.

  • Harvest and postharvest brown rot of fruit in relation to early latent infection caused by Monilinia spp. in Hungary
    17-19.
    Views:
    816

    In this study, the effect of early latent infection caused by Monilina spp. on harvest and postharvest brown rot of sour cherry and peach was investigated. Two field experiments were performed in commercial orchards located at Eperjeske on sour cherry and at Siófok on peach in 2013 and 2014 in order to study the possible relationship between the incidence of early latent infection caused by Monilinia spp. and the incidence of harvest and postharvest brown rot. No latent infection was recorded at popcorn phanological stage of the trees at both locations. The maximum incidence was detected during the pit hardening period. There was a positive  correlation between the incidence of latent infection and harvest or postharvest brown rot. The average  incidence of latent infection during the crop season explained approximatelly 20% of the total variation in the incidence of postharvest brown rot.

  • Effects of environmental factors on morphological and quality parameters of table beet root
    139-146.
    Views:
    592

    In our trial morphological and quality parameters of 15 table root varieties were tested at 3 different sowing dates: 15 April, 9 July and 19 August 2010. In the trials the root shape of the varieties form the April sowing date approached most the regular spherical shape (diameter/length –1.0) which is favoured both by fresh market and the processing industry. In the July and August sowings the roots were elongated with reduced proportions. The highest red pigment content (betacyanin) was observed in the second sowing of July (>80 mg/100 g). In the late sowing (August, under plastic tent) a further 10–20 mg/100 g pigment increase was measured in relation to the earlier sowing dates of the same varieties. A similar trend could be observed in yellow pigments (vulgaxanthis) which proves a close correlation between the quantities of the 2 pigments (r=0.823). The highest vulgaxanthin content (103.3–124.18 mg/100 g) was obtained form roots of the late sowing harvested in December. Varieties reacted differently to temperature and so to sugar accumulation in the different sowing periods. In the July sowing higher water soluble solids content was measured on the mean of varieties (10.12 %) as compared to the April sowing (7.76%). Sensory evaluations included inner colour intensity (1–5), with ring (1–3) and taste (1–5) of the raw material evaluated by scoring. According to laboratory measurements better inner colour intensity was observed in the July and August sowing dates. In these samples uniformly coloured, almost with, ring-free roots were obtained. In our trial varieties from the spring sowing had superior taste. Early sowing is recommended for fresh market sale while the second crop (July) harvested in autumn can satisfy processing requirements. In the late sowing (under unheated plastic tent) fresh beet root can be grown at the end of autumn or beginning of winter, thus prolonging the usability of plastic tents.

  • Comparison of macrofungi communities anti examination of macrofungi-plant interactions in forest stands in North Hungary
    101-103.
    Views:
    278

    Parallel phyto- and mycocoenological investigations have been made since 2001 in all characteristic forest types in Borzsony Mts., North Hungary. The main aim of this work was the examination of similarities between plant and fungal communities, as well as the plant—fungi connections within certain habitats. Among the total 381 macrofungi species documented, 330 occurred in the investigated 7 forest stands. Wood-inhabiting fungal communities of coniferous stands can be separated unambiguously from those of deciduous stands. Communities of deciduous stands can be divided into two subgroups: those fructifying in wet and in semidry stands. The main factors which influence the composition of wood inhabiting fungal communities seem to be, in decreasing order: (1) crown layer composition; and (2) soil properties (probably only humidity). Wood-inhabiting fungal communities do not show any relation with the underwood layer of particular plant associations. Amongst soil inhabiting fungal communities, three groups can be separated: (1) those of coniferous stands and alderwood; (2) those of the two climax stands; and (3) those of the two edaphic deciduous stands. Classification of these communities is similar to classification of plants of underwood layers. Probably both are dependent upon soil properties (humidity and pH) of particular habitats, but the range of mycorrhizal partners is also decisive for macrofungi communities. All investigated stands are under forestry management, with low quantity of dead and infected wood, so forestry management type may have a great influence in composition of both wood and soil saprotrophic fungal communities.

  • Examination of valuable ingredients of some wild fruits
    71-74.
    Views:
    383

    A possible way of the development of Hungarian agriculture is the selection and growing of new fruit species and varieties featuring special qualities, with high biological nutritive and health protecting properties due to their natural composition. A reserve for such new fruits is the native dendroflora, e.g. those wild-growing trees and shrubs of Hungary, which bear edible fruits. The publication is giving a summary of chemical analyses done on the fruits of the plants listed below. The research team on the project started the work in 2001 with

    woody species (genera) as follows:

    • common elder (Sambucus nigra) clone named Szcs-1, Szcs-2, Szcs-3, Szcs-4, Szcs-5, SzcsK-1, SzcsK-2
    • dog rose (Rosa canina) types: clones named Sz-1, Sz-2, Sz-3, Sz-4 and Sz-5 .
    • native rowans: Sorbus dacica, S.rotundifolia, S. degenu, S.bakonyensis cv. Fánivölgy
    • hawthorns: Crataegus monogyna, C. orientalis,C..v lavallei.
    • cornel cherry: Cornus mas cv. Császló.

    The present paper is reporting on the content of the following compounds in the fruits: dry matter (refractometric values), total acid content, ascorbic acid, 13-carotene, pectin, minerals and carbohydrates. The results have shown that these wild fruits have excellent composition. Besides their curative effects, their content of minerals, ascorbic acid and 13-carotene has surpassed that of the traditional fruits. These fruits are rich in ascorbic acid, 13-carotene and pectin. The high content of the above-listed, biologically active compounds makes the new wild fruits studied suitable for the preparation (and later: mass-production) of special curative and exclusive products.

  • Resistance Gene Analogs (RGA) as a tool in fruit tree's breeding
    7-15.
    Views:
    391

    Breeding for pest and disease resistance comes as a major objective behind the fruit traits. To increase the effectiveness of fruit resistance breeding application of the Marker Assisted Selection ( MAS) is advantageous. For generating molecular markers which enable the following of interesting traits basically two methods are available: targeted marker design based on conservative region of already known Resistance ( R) gene sequences or randomly generated markers. The creation  and the application  of  these homology  based  markers  are the object of this review in  the main  temperate zone  fruit species.

  • Illumination-Independent Reflectance Information Acquirement for Leaf Water Potential Measurement on the Example of Satsuma Mandarin
    75-79.
    Views:
    218

    Mandarin fruit sugar content can be increased when subjecting the satsuma mandarin tree (Citrus unshiu MARC. var. satsuma) to moderate water stress by mulching during the period of active sugar accumulation, thereby fruit quality improvement can be realized. In the frame of the precision agriculture production system, a non-destructive measuring method development became necessary based on remote sensing, field spectroscopy and image analysis, to be able to measure the degree of water stress. Large amount of visual information have been recorded at ground level, in near infrared, red and green channels by a false color digital camcorder designed specially for remote sensing applications. A method have been found to be able to calculate the absolute reflection of mandarin leaf surface by comparing leaf reflectance with known reference target reflectance, thereby established the basis of further studies in this topic. Leaf absolute reflection can be measured reliably, under variable natural illumination at field conditions. Functional correlation can be searched between visual information and leaf water potential measured by PMS pressure chamber.

  • Vegetative Indicators of sour cherry cultivars and resistant clons
    55-58.
    Views:
    358

    Sour cherry is a hungaricum. Hungary has several excellent and self fertile sour cherry cultivars. Hungarian sour cherries have a name for fruit quality and they are suitable for fresh consumption. Today breeding is focused not only on fruit quality, but also on disease resistance. The new, investigated cultivars have these characteristics too. But growth characteristics are also very important because they contribute to successful production. The vegetative and generative properties of the cultivars are different. If a cultivar is very productive, the ignorance of cultivar-specific pruning may result in the decrease in tree condition and fruit quality. The properties of producing fruiting wood greatly determine the renewal capabilities of cultivars. Knowing these properties is essential in case of sour cherries, the fruit species that requires a lot of sunlight and tends to produce bare wood. The research of candidate cultivars until now focused on fruit quality. Our aim was to investigate the vegetative characteristics of the resistant ‘bosnyák’ cultivar group in detail, defining the growth characteristics of these cultivars.

  • Irrigation Requirements for Grape Crop under Climate Changes Conditions in Egypt
    23-27.
    Views:
    499

    The present work is mainly directed to discuss sensitivity of climate changes upon the irrigation demand for grape crop in Egypt. The Penman Monteith equation was used to calculate reference Evapotranspiration (ETo) under current and future climate for the two locations (El Menya and El Beheira). The historical climate data for ten years from (2000 – 2010) was used as current climate to calculate irrigation requirement for grape crop under Egyptian conditions. Two climate changes scenarios have been applied as changes in temperature. The first scenario supposed that increasing in temperature of 1.5°C would happen, and the second scenario supposed that increasing of 3.5°C would happen to calculate reference Evapotranspiration and irrigation requirement for future climate. The results showed that the evapotranspiration and irrigation requirement for grape crop at El Menya location higher than El Beheira location. Irrigation demand for grape plant under two climate changes scenario will increase in El Menya and El Beheira locations. El Menya location will take the highest irrigation demand under climate changes. Therefore, possible adaptation countermeasures should be developed to mitigate the negative effects of climate changes for the sustainable development of agro-ecosystems in Egypt.

  • Economic aspects of aged apple plantations in Hungary
    13-16.
    Views:
    350

    Being competitive is a goal all over in the EU. Competition is free and getting closer among the competitors of the apple industry. In Hungary, one of the most important issues of apple industry has been what are the prospects for aged plantations, which account for 50% of crop land. Based on our results, 80% of those apple plantations on the down-grade yielding apple, the ones only for processing, do not meet the criteria of competitive production. For those plantations in better shape that yield 30-40 t/ha, of which at least 20-30% are for fresh production, it can he profitable. Because of the future trend in technology and economy, however, even the latter ones can not be considered being competitive in the long run.

  • Effect of different non-chemical treatment methods on organic seed
    63-65.
    Views:
    223

    The importance of ecological farming in Hungary is increasing. The utilisation of organic seed is regulated by national law. In our experiment the effect of two plant conditioning substantial: Biokál and Biomit Plussz were tested on the germination of seed. Our test plant species was garden pea (Pisum sativum L.), the most important vegetable in Hungary. The experiment was carried out in the germination laboratories of the National Institute for Agricultural Quality Control after international rules. The germination, the length of root and shoot were measured. 4 hours soaking of pea seeds in 30% solution of Biokál gave the best result. Our results could help to make the field emergence of organic seed faster and safer.

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