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  • Prediction infection risk on the basis of weather-related factors and Erwinia amylovora colonization in apple and pear flowers
    39-54.
    Views:
    170

    Current infection risk prediction models utilize environmental parameters and field records, but do not take into account the estimated inoculum potential within the orchard. The object of this study was to survey the accuracy of three simple prediction methods under Hungarian climatic conditions, which could easily be used by the farmers. We also tested whether the accuracy of infection risk predictions can be improved by taking into consideration the incidence and/or rate of flower colonization by Erwinia amylovora.

    After preliminary investigations in 1999-2001, data concerning the weather-related infection risk were recorded in 5 apple and 1 pear orchards in 2002, and in 12 apple and I pear orchards in 2003. The weather data were processed by the easy-to-use risk assessment models of the mean temperature prediction line (MTL), Smith's Cougarblight 98C and Billing's integrated system (BIS), and by the MaryblytTM 4.3 computer-assisted model for reference. The population size of E. amylovora in the flower samples was estimated within an order of magnitude by PCR.

    For all years and orchards tested, Maryblyt indicated 35 days on which there was an acute infection risk. The same days were indicated by all 3 methods in 23 cases (66%), 8 days were indicated by 2 methods (23%) and 4 days were indicated by 1 method only. A similarly good correlation was found for prediction of the date of the first massive infection risk: in 2003, for instance, there was a perfectly consistent prediction by all 4 models in 9 of the 13 participating orchards. A coincidental forecast was provided by 3 of the 4 models in the other 4 orchards.

    The results indicate that any of the risk assessment models could provide an increased accuracy of the actual infection risk prediction if combined with an estimation of the incidence of Erwinia amylovora colonization in the open flowers. We found no convincing differences in the size of the epiphytic population in flowers of cultivars possessing high or low susceptibility to Erwinia amylovora.

    We conclude that the easy-to-use methods tested could be used by the fanners to recognize weather-related risks, especially when coupled with an estimation of the proportion of the pathogen-infested flowers. This local prediction would provide rapid information (faster than the regional forecast systems) specifically for a given orchard.

  • Comparison of pear production areas from yield risk aspect
    25-28.
    Views:
    391

    There are three main pear production regions in Hungary. The most relevant is theWest-Transdanubian (Zala, Vas and Gyôr-Moson-Sopron counties), where up to 30% of total pear production occurs. The second most productive region is Pest County, where pear is grown mostly in gardens and garden plots, resulting in 15-20% of Hungarian production. In the northern Hungarian region (Bodrog valley in Borsod-Abaúj-Zemplén, Heves and Nógrád counties), the microclimate is perfect for optimal pear production. In our analysis, we focused on four plantations that are dominant in pear production in Hungary. Two of them are situated in south-western Hungary, one of them is in South Transdanubia and one is in North Hungary. Considering the personal attitude of the decision maker towards risk, the best alternative is ‘Williams’ in Alsóberecki, as the yield risk is the lowest with this variety, while the second best alternative is ‘Bosc Beurre,’ also produced in Alsóberecki. This is an irrigated area, and this fact evidently decreases the yield risk. The highest risk is in Bánfapuszta and in Zalasárszeg, for the non-irrigated ‘Williams’ variety. The highest yield with the lowest risk can be obtained with irrigation. Nevertheless, in the case that relevant data are available, and by incorporating cost and expected profit data, the stochastic dominance method is suitable for financial risk assessment, as well.

  • Hazardous element content and consumption risk of 9 apricot cultivars
    61-65.
    Views:
    309

    The heavy metals pollution is one of the problems that arise due to the increased uses of fertilizers and other chemicals to meet the higher demands of food production for human consumption. In order to assess possible health risk of apricot (Prunus armeniaca L.) consumption, levels of Arsenic, Cadmium, Mercury and Lead were determined in fresh and dried samples of "Jumbo cot", "Tom cot", "Gold strike", "Gold bar", "Bergeron", "Bergarouge", "Sweet cot", "Yellow cot" and "Zebra" apricot cultivars. Wet digestion of samples with concentrate HNO3 – H2O2 digester mixture and inductively coupled plasma–atomic emission spectroscopy was used. Highest content of As, Cd, Hg and Pb among all cultivars, were 0.5, 0.04, 1.5 and 0.5mg/kg of dried apricot samples. Fresh fruit samples also contain 0.2, 0.016, 0.6 and 0.2 mg/kg of Arsenic, Cadmium, Mercury and Lead respectively. Daily intake of metals, hazard quotient and health risk index to reveal health risk possibility of dried and fresh fruits consumption were calculate and compared.

  • Calculation of climatic probability of winter and spring frost damages in the main peach and apricot growing districts of Hungary
    99-106.
    Views:
    227

    The probability of winter and spring frost damages experienced in peach and apricot plantations has been assessed in 5 growing regions of Hungary (Szeged-Szatymaz, around the lake Balaton, Mecsekalja, hills of Buda, Mátraalja) and (Mecsekalja, hills of Buda, Pest­Godo116, Duna-Tisza Mize, Matra-Bükkalja) during the period between 1951 and 2000.

    Frost tolerance of flower buds on a given shoot sample is expressed by the mean value assessed after frost damage (LT50), and the meteorological records of the growing sites raised between 1951 and 2000 are used to calculate the probability of frost damage. In peach, the difference between growing sites and between varieties may become two fold as for the chance of repeated frost damage at a probability of 50 %. In apricot, the probability of frost damage may exhibit differences between growing sites up to 20 % as for susceptible varieties, and 16 % for frost tolerant varieties. Frost damage may vary between 4 and 18 % depending on the genuine frost tolerance of the varieties. Peach is afflicted by low temperature causing substantial losses of yield at the highest probability in the region Szeged-Szatymaz and at the lowest in Mátraalja. Apricot is, on the other hand, most endangered in the Duna-Tisza Mize region, while the lowest probability of frost damage is expected around Mecsek and Buda.

    The critical period of frost damage in the mid of January in Szeged-Szatymaz region, in Mecsekalja the mid of February showed the highest probability of frost damage. All growing sites are frequented at high chances by frost damages occurring during and closely after the blooming period. Duna-Tisza köze is mainly afflicted in early March, whereas Mátra-Bükkalja in mid of January and each March.

    The probability of temperatures below zero degree has been assessed in all the 5 regions observed. Around April 5-8 the probability of freezing temperatures diminishes steeply at all sites, whereas the risk of frost increases again around April 9— 11. That climatic peculiarity of should be taken into consideration in choosing growing sites or varieties.

    Postulating the effects of a global warming up of the climate, the chances of avoiding frost damages at different growing sites by delaying the blooming dates are considered. According to our calculations, the delay of blooming by 5 days may diminish the risk of frost damage by 4-20 % at the growing sites examined, whereas a delay of 10 days reduces the risk by 37-85 % in both fruit species.

    Calculations offered an answer on the question of climatic changes, whether the probability of winter and spring frosts damage changed during the 50 years. The long list of data shows the diminishing chances of winter frosts, while the probability of temperatures risking spring frost damages increased after the early 1970-es up to now.

  • Comparative analysis of the production risk of major fruit species
    119-122.
    Views:
    180

    Hungary possesses excellent agri-ecological potentials even in an international comparison. Despite their decreasing economic weight, agriculture and food production are of great significance, since the supply of the population with high quality and inexpensive food is a fundamental social demand and one of the essentials of the quality of life. The development of vegetable and food production is of great importance both from the aspect of healthy nutrition and comparative advantages (cheap workforce, professional expertise, traditions of production, climate favourable for quality). Within the Hungarian fruit production apple and sour cherry are essential branches in virtue of their significance. It is widely known, that – though to a different extent in the case of certain fruit varieties – satisfaction of the need for appropriate habitat is one of the important conditions of a decent quality and secure production. In my research, I analyse the territorial distribution, production standard and production risk of the Hungarian apple and sour cherry branches. I did not have the opportunity – because of the imperfections of the database – to compare long time series, therefore I examine the random effects affecting production by using the data of 3 years (they have the same content). I ranked and assessed each habitat and the production risks of certain fruit species compared to each other on the basis of indexes of relative deviation.

  • Spatial and temporal variation of extremely abundant maxima of precipitation in Hungary during the period between 1951 and 2010
    107-114.
    Views:
    410

    The study deals with the accumulated database of 16 meteorological stations in Hungary during a period of 60 years. The purpose was to reveal the spatial and temporal structure of the appearance of extreme values in the daily distribution of data concerning precipitation. We strived to answer the question whether the frequency of incidences of daily maxima did they change or not during the 60 year-long period in the main growing regions of the country. It is demonstrated on geographical maps how the size and frequency of precipitation episodes ensued, and what are the typical traits of changes in intensity as well as in frequency of happenings projected according to their spatial and temporal distribution. From the point of view of fruit and vegetable growing, it is of prime interest what kind of frequency and intensity of changes occurred in precipitation. The temporal distribution of extremities though did not seem to change signifi cantly in some areas, but the recognition of changes may help conspicuously the planning and the choice between alternatives of species and varieties as well as technologies of horticultural managements for the long run. Extremely intense rains during a short time may cause erosion and stagnant water, thus we have to know what are the odds of risk. The temporary distribution of changes helps us to judge upon the reality of anxieties, which are expected according to the existence of trends. Seasonal or monthly distribution is visualised by maps, what is expected and what is accidental as for a decision in planning. The spatial distribution of coeffi cients of variation help us to decide what is the local chance of extreme happenings at different parts of the country and what is its coeffi cient of uncertainty. The risk of any undertaking dependent on conditions of weather could be expressed numerically by a coeffi cient of risk.

  • Temporal changes of the frequency of spring frost damages in the main fruit growing regions in Western Hungary and in East Hungary
    81-87.
    Views:
    416

    Most of the risk in Hungarian fruit growing is the damage caused by late spring frosts. The frequency of late frosts seems to increase nowadays. The aim of the study was to check this contention: what is the real probability of the damages. Based on earlier experiences, the physiological LT50 function has been elaborated for new fruit varieties, which are eligible to moderate the danger when being threatened by frost. By means of this technique, the probability of freezing is distinguished between frost susceptible, frost resistant and medium frost resistant fruit species and varieties around their blooming time. The degree of frost damage depends on the duration and severity of the low temperature and not at least on the frost tolerance of the plant. For that purpose, the frequencies of frost damages were studied at two Transdanubian and two Trans-Tisza fruit growing sites by means of a meteorological database for the 60-year-long period 1951–2010. Being aware of the LT50 values changing during the phonological phases of the fruit trees from budding, bloom, fruit set and fruit growth, the number and date of critical (frosty) days could be settled. An important role is attributed to the orographic relief and the height above the sea level of the site, as 20–30 m differences and expositions may become decisive within the same plantation. The spatial distribution of damages is also dependent on the air circulations within the Carpathian basin. At the southern and northern borders of the country, especially valley bottoms represent additional risks of frost. Most spring frost damages are experienced in April 20–22, and cause heavy damages by temperature minima between – 3°C and – 6°C. The severity of damage depends largely on the temperature of the preceding few days. The earlier bloom the heavier damage is expected. The study is emphasising the importance of the varieties. Frost tolerance of some varieties may lower the risk of spring frosts by 40–50%, as experienced on the plantations. The quantifi cation of the risks based on data raised during the last years will be suitable to defi ne the security of yields of each growing site successfully.

  • The Hungarian peach production risks
    85-89.
    Views:
    192

    Hungary possesses very good agroecological conditions even in a European comparison. Agriculture and food production is highly important despite its decreasing relative economic significance, since providing high quality and affordable food for the population is a basic social necessity and one of the decisive factors in quality of life. The development of vegetable and fruit production is of great importance both from a healthy nutrition as well as from a comparative advantage (cheap labour, expertise, production traditions, favourable climate) point of view.Vegetable and fruit consumption per capita is lower than in developed countries, which is a decisive indicator of healthy nutrition, but improvement is continuous and desired. Appropriate quality and quantity in production is a requirement to meet customers’ needs in a highly competitive market from one year to the next. Hungary can only be competitive if production results are improved while risks are reduced. Fruit production is a sector with high capital requirements, risk assessment is very important from a production, investment as well as from a national economy point of view. Our examinations will focus on production risk, which is present in the annual fluctuation of average yields, especially as a result of extreme weather factors.

  • Total anthocyanine content and antioxidant density of some Hungarian sour cherry varieties
    109-111.
    Views:
    435

    Evidence suggests that a diet high in fruits and vegetables may decrease the risk of chronic diseases, such as cardiovascular disease and cancer, and phytochemicals including phenolics, flavonoids and carotenoids from fruits and vegetables may play a key role in reducing chronic disease risk. Recent research has proven that sour cherry (Prunus cerasus L.) is a valuable natural source of some bioactive compounds important in human health preservation. In our work, we identified the total antioxidant activity, anthocyanine content and "antioxidant density" of sour cherry varieties named "Újfehértói fürtös", "Debreceni bőtermő", "Kántorjánosi" and "Érdi bőtermő" and those of the "Bosnyák" sour cherry clones. "Antioxidant density" is a biological value indicator obtained in a synthetic way, which indicates the antioxidant capacity of the particular food, e. g. fruit and vegetable, related to 1 Calorie.

  • Challenges of the vegetable and fruit market
    83-89.
    Views:
    317

    The situation of the horticulture sectors have been in the limelight of the professional and economic decision makers all over Europe. This article analyses the situation of the sector from economic point of view and reveals the main reasons of its low income and high risk. It concludes that one of the biggest problems is the trading uncertainty in the vegetable and fruit sector that is caused by the asymmetric market structure of the post-regime era. Since sizes of vegetable and fruit plantations do not allow producers to supply individually the extremely concentrated food retail trade or the processing trade they must find alternative ways for trading their products. The study introduces two alternative solutions. One alternative is foundation of modern multi-level producer co-operatives with the help of EU subsidies. Secondary and tertiary co-operatives may achieve better market position and lower trading price risk with managing production, professional marketing, and improving the information flow. The other alternative is searching for new trading channels such as local provision, restructuring of local markets, and direct trade (home delivery and pick-it-yourself programmes). The shorter producer-consumer distance means better quality at lower price for customers and income in the case of smaller amount of products for producers. It is concluded that both solutions together or separately may help individual producers in their trading problems. However, whichever way they choose, producers must co-operate.

  • Climate change impacts and product lines
    79-83.
    Views:
    230

    This paper summarizes the main effects of extreme weather events on agricultural production and demonstrates their economic consequences. For cost-benefit analysis of economic impacts and for determination of risk levels simulation models are needed that contains the relationship between product line levels and elements. WIN-SIM model is developed for this goal, specialized for wine production. The model is suitable to analyze the market share, the cost and income relations as well as the relation structure of the product lines. The four levels of the model (site, vine growing, wine production and wine market levels) have individual values added from the aspect of end product, where the product line sets out from the site level and gets through the levels up to the consumer segments. Theoretically, all elements can be connected to any element of the next level and sublevel, but there are “prohibited contacts” because of professional, regulation or production practice reasons.

  • The effect of wear of petrol engine power brush cutters on their vibration exposure
    37-44.
    Views:
    207

    The matter of noise and vibration exposure has an accentuated emphasis in the environmental protection policy of the European Union. In practice, the focus is on the evaluation of noise -strain. The evaluation on human beings' vibration-strain is in focus in recent years. At the Technical Department in Corvinus University of Budapest Faculty of Horticultural Sciences we evaluate in PhD training form the possible ways of alleviation and revealance of noise and vibration-strain in gardening devices and machineries. According to the latest development in gardening culture, small gardening machines are more and more widespread. There is a law in Hungary for the compulsory grass-cutting, especially on 'ragweed' (Ambrosia elatior). Along highways, public territories, parks workmen at least six months are in charge to terminate these weed-crops meanwhile they are endangered by serious harmful effects. The operators of hand-held power tools are exposed comprehensive levels of hand-arm vibration at the tool-hand interface. Many studies indicate that extended exposure to mechanical vibration can induce degeneration of the vascular and sensioneural systems in the hand called hand-arm vibration syndrome (HAVS). The precise mechanism for the initiation and development of HAVS is unclear to date. Measurement and risk assessment of hand-transmitted vibration is mostly based on the guidelines and dose-response relationship provided in the ISO-5349 standard. These guidelines suggest that the magnitude, frequency, direction and duration of vibration exposure are the most important variables for the risk assessment of hand-arm vibration. This current study is focusing on brush cutters owned by one of the biggest caretaker company. These machines have similar brand and age but different in usage time. We inquired seven brush cutters through two years. The manufacturer repaid the vibration level of the new machines, but they doesn't examine, whether extent of the vibration emission is changing for the proper use. We wanted to know that are there any differences between the values of vibration specification after certain time of usage. Is it possible to monitor the alternate movements on graphs according to the vibration sciences? By Ill octave band frequency and FFT analysis we can point at that these brush cutters can show differences in critical frequencies. These biases can influence the hand-arm system and its vibration-strain burdening.

  • The atmospherical drought as a decisive factor of yield in the main sour cherry varieties of Hungary
    121-125.
    Views:
    253

    Atmospheric drought causes heavy diffi culties of water supply in most fruit species grown in Hungary, although the modern, intensive plantations are already equipped with irrigation. The use a dripping systems are widely applied, therefore nothing was done to avert the risk of atmospheric drought. In excessively dry seasons the reduction of yields is often due to atmospheric drought. Present study aims to utilise measured data of meteorological parameters (relative air humidity and temperature) to develop an index to characterise drought and measure its effect on fruit yield. Causes influencing yields are multiple. Phytosanitary problems are combined with defi cits of water supply. Water deficit of the soil is avoided by dripping irrigation, but the atmosphere is infl uenced by sprinklers only. Atmospherical drought increases the transpiration of the trees intensely and causes reduction of photosynthetic activity, consequently impairs the yield. Applying the index developed in a plantation of 6 sour cherry varieties grown in Hungary (Meteor, Nefris, Pándy, Újfehértói fürtös, Kántorjánosi, Debreceni bôtermô), we measured the specific yields (yield per volume of tree crown) during the period 1989–2011 using the meteorological database of the growing site. Additionally, other parameters characterising the drought are compared and searched for a method most reliable for judging the specific yielding capacity of sour cherry varieties. The results proved convincingly the utility of the index, especially for the varieties Pándy and Újfehértói fürtös. Comparison with other indices expressing the effects of drought revealed the superiority of our index, which will be applied in the future to express the risk of atmospheric drought.

  • Feasibility of investments in Hungarian grapewine sector
    37-42.
    Views:
    200

    Investments in the vine growing-wine making sector can be characterised by a high level of' risk, and an important role of time, because there is a considerable time gap between the decision on investment and its consequences, whereas the ecological and economical factors should be considered as stochastic variables. Based on a real—life, typical vine—plantation project, the article analyses the profitability of vine growing-wine making sector as a function of different ecological and economical conditions depending on the added value content of products. Results of the investigations highlight: (1) the importance of subsidy for establishment of vine plantations: (2) the considerable influence of yields on rate of return of investment; (3) the role of increasing of added value content of products. Importance of the utilisation of alternative channels of distribution and the formation of producers' cooperatives are underlined, being based on calculation of return of investment.

  • High antioxidant - and anthocyanin contents of sour cherry cultivars may benefit the human health: international and Hungarian achievements on phytochemicals
    45-47.
    Views:
    448

    Evidence suggests that a diet with high fruit and vegetable consumption may decrease the risk of chronic diseases, such as cardiovascular diseases and cancer, and phytochemicals including phenolics, flavonoids and carotenoids from fruits and vegetables may play a key role in reducing chronic disease risk. Recent research has proved that sour cherry (Prunus cerasus L.) is a valuable natural source of some bioactive compounds important in human health preservation. According to the published data, the most important biological effects of sour cherry are connected — directly or indirectly — to their endogenous antioxidant behaviour as well as to their specific pattern of anthocyanin components. In the present work, we measured the total antioxidant capacity of some Hungarian sour cherry varieties in combination with their anthocyanin-, and vitamin-C content. In 2003, twelve clones were selected and grafted from a local sour cherry population called "Bosnyák" sour cherry grown in small home gardens and farms of the village Csengod (Great-Plain Region, South Hungary). Other Hungarian sour cherry varieties, i.e. cv. Újfehértói fürtos, cv. Érdi bőterrnő, cv. Debreceni bőterrnő, cv. Csengődi and cv. Kántorjánosi served as a control.

  • Damages caused by winter frosts, their temporal variation and frequencies in the main fruit growing region of Transdanubia and of the East Tisza regions of Hungary
    89-97.
    Views:
    251

    The aim of the study was the study of winter frost damages, especially their changes expressed in temporal frequencies on the main fruit growing regions of the country. In our earlier paper, we introduced the calculation with the term LT50 as the quantitative expression of temperature threshold, when the lethality halves the survival of plant organs, buds or cells causing 50% death rate. The damage is highly dependent on the temperature and on its duration (length of time), but not at least on the frost tolerance of the fruit trees. The incidence and severity of damage is analysed according to the apricot and peach varieties of their different susceptibility or tolerance too. Four fruit growing regions, two of the in Transdanubia and two belonging to the regions east of the Tisza river have been selected to trace the incidence and severity of frost damages. For that purpose, we analysed the history of the past 60 year period, 1951–2010, utilising the database of the network of 16 meteorological stations of the countrywide service. Being aware of the values of LT50 during the rest period and afterward, the compulsory dormancy caused by low temperature, the number of days, the probability of frost damage could be predicted. The role of the orographical profi le, the height above sea level and the exposition of plantations are also decisive. Within the same plantation, 20–30 m difference of level may cause large diversity in temperature and frost damage. Air circulation and regular incidence of winds within the Carpathian basin modify the occurrence and severity of damages. Lowlands near the southern and northern country borders are particularly exposed to winter frosts. Most damages are reported in February, as temperatures below –20 °C especially if the fi rst part of the winter was mild, or in January was a warm period. With the end of the physiological rest period of the trees, the frost-susceptibility increases signifi cantly, and a cold period of –15 °C may cause heavy damage. This study proves that tolerance of varieties infl uence the damages substantially. By planting frost tolerant varieties, winter frost damages could be diminished by 40–50% at the same growing sites. Present results may also offer a tool to estimate the risk of frost damages and express the security of yields at a given site based on the data accumulated in the database over many years.

  • Factors affecting apricot fruit antioxidant capacity and mineral element contents
    95-99.
    Views:
    235

    Several epidemiological studies revealed that the consumption of antioxidant compounds and the risk of atherosclerosis, increased blood pressure or cancer are inversely proportional. The individual amounts and relative proportions of macro- and micro elements present in food is also of great consideration since these are involved in a wide range of physiological processes including the influence of the redox homeostasis. The antioxidant power and mineral nutrient content of fruits might be affected by several factors including genotype, ripening stage, year-effects or a wide range of environmental conditions. This study was carried out to survey the antioxidant power and mineral element content in fresh fruits of apricot and analyse some genetic and environmental factors that may have important contribution to the inner content of apricot fruits. In addition, the influencing effect of the extraction procedure used for antioxidant analyses was also tested. Our analyses indicate that a considerable fraction of antioxidant capacity is attributable to the hydrophilic antioxidants. The genetic background has crucial importance in determining apricot fruit antioxidant capacity and mineral nutrient content; however, the growing season and the ripening time of fruits may have also important effects.

  • Role of organosilicone surfactant in apple scab control under scab conducive weather conditions
    23-25.
    Views:
    216

    Fungicides of integrated fruit production (dithianon, captan, and diclofluanid) and an organosilicone surfactant were compared in spray schedules from green tip until summer in order to control apple scab caused by Venturia inaequalis and to evaluate their phytotoxicity on fruit. Sixteen sprays of 1.8 kg ha-1captan, 0.41 ha-1 dithianon, and 1.8 kg ha-1 diclolfluanid significantly (P=0.05) reduced the incidence of leaf or fruit scab compared to unsprayed products. All fungicides applied with organosilicone at 0.1% resulted in lower incidence of scab on young and older leaves as well as on harvested fruit, but these were not statistically always better than fungicides applied alone. In case of diclofluanid, the fungicide applied with organosilicone at 0.1% resulted in significantly lower (P = 0.001) incidence of scab on young and older leaves. Diclofluanid applied with organosilicone at 0.1% gave the best scab control on leaf and fruit. Treatments applied with fungicides alone had no significant effect on plant phytotoxicity compared to untreated control. All fungicides applied with organosilicone at 0.1% increased (P = 0.05) fruit damage compared to untreated control or fungicide applied alone, though these were not always significantly different. In case of percentage of fruit russet, treatment of dithianon 0.4 1/ha + 0.1% organosilicone significantly increased fruit russet, while fruit russet index significantly increased in the treatment of diclofluanid 1.8 kg/ha + 0.1% organosilicone compared to untreated control. In sum, application of surfactants can help to increase efficacy of scab fungicides; and consequently, to reduce the risk of fungus infection under high scab disease pressure. This fact may also be helpful in fungicide resistance management and reduced-spray programs with accurate scab warning systems.

  • Antioxidant capacity, total phenolics and mineral element contents in fruits of Hungarian sour cherry cultivars
    59-64.
    Views:
    483

    Several epidemiological studies revealed that the consumption of antioxidant compounds and the risk of atherosclerosis, increased blood pressure or cancer are inversely proportional. Fruits of sour cherry contain a wide range of antioxidant compounds including melatonin, perillyl alcohol, ellagic acid, several flavonoids, polyphenolics, and anthocyanins. This study was carried out to survey the antioxidant power and mineral element content of seven commercial sour cherry cultivars and three cultivar candidates and to assess the influence of some external conditions on fruits' functional properties. Our analysis revealed nearly 5- and 2-fold differences between the lowest and highest antioxidant capacities and total phenolics content, respectively. Some cultivars (`Kántorjánosi' and ‘Újfehértói fürtös') and cultivar candidates (D, 'Petri' and 'Éva') showed outstanding antioxidant capacity and total phenolic content; in addition, mineral element content in fruits of the ‘Újfehértói fürtös' cultivar was also favourable. Redox parameters of fruits were influenced by the cultivation plot or fruit positions within the canopy in about half of the cultivars tested. Genetic background of cultivars forms the decisive factor in determining fruits' antioxidant capacity, although external factors may have also sizeable modifying effects. Enhanced functional properties of the fruit may also be further increased through breeding programs since considerable variation exists within the tested germplasm.

  • Dynamic analysis of a simple fruit tree structure model
    53-55.
    Views:
    132

    The effect of shaker harvest on root damage was studied on a simple tree structure model. Equations were set up to be able to calculate the relation between shaking height and stress in the roots. To get the strain at break data field experiments were carried out. The acceleration versus time curves were recorded on different heights of the stem. Evaluating measured and calculated data it can be concluded, that the risk of root damage increases when

    • the height of shaking is decreased,
    • the stern diameter is smaller, and if
    • the unbalanced mass of the shaker is increased.
  • Relationship between zinc and cadmium contents and cultivating conditions of gourmet and medicinal mushroom Agaricus subrufescens
    21-27.
    Views:
    328

    Almoust half of the world’s population is at risk for inadequate zinc (Zn) intake, a strategic trace element that is necessary for a healthy immune system. A lack of zinc can make a person more susceptible to disease and illness. There is a need of defining additional sources of zinc in diet. Cadmium (Cd), however, and its toxicity in food chain receives considerable public and scientific attention. Cd is primarily toxic to kidney and can cause bone demineralization. In many areas in the EU, intake of Cd is not far from maximum tolerable. Mushrooms are well known for accumulating metal ions such as zinc and cadmium. Objective of this study was to define relationship between cultivation systems and conditions on zinc and cadmium content in fruit bodies of Agaricus subrufescens grown on different substrates. Cultivation was performed on mushroom composts based on increasing amount of digestate from anaerobic digestion treatment processes mixed with wheat straw and paper. The Zn and Cd concentration was defined in fruiting bodies, correlated with yield, flush and element concentration in substrates. Results showed percentage of food waste digestate and other components used in experiment had influence on concentration of Zn and Cd in mushroom compost and in A. subrufescens. Zn accumulated in collected mushrooms in amounts reaching from 42.8 to 126.9 mg kg-1 Cd content ranged 2.6 to 17.9 mg kg-1. Significant correlations for Zn concentration between mushrooms and substrates showed increase of Zn in mushrooms when cultivated on substrates with higher amount of digestate.

  • Flower density and winter damage of apricot and peach varieties
    53-56.
    Views:
    291

    Hungary is located on the northern boundary of economical apricot and peach production. The present assortment of varieties and the actual, not adequately selected growing sites cause a permanent risk of winter and spring frosts in their cultivation. The field observations are performed at Debrecen, the Experiment Station Pallag, on 20 apricot and 21 peach varieties. The flower density among the varieties attained 3-4-fold differences. Three categories have been suggested for both species. The density was inferior in Hungary established varieties compared with the new varieties of foreign origin. The minimum temperatures of January 9, 2009 was –17,6 °C , and of December 21, 2009 also –17,6 °C. In some varieties the damage of buds attained 100%. For estimating the yield security, we need to consider also the flower density and the frost damage together. For a mediocre yield, we need a flower density in both species of at least 0.2 living bud/cm. The results confirm the statement that in Hungary, the revision of growing sites is indispensable in order to develop a profitable and competitive apricot and peach growing industry.

  • The utilisation of nutrient elements in soilless cultures of vegetable production
    47-49.
    Views:
    204

    Vegetable production in greenhouses may impair the ecological balance of the environment substantially as far as being uncontrolled. Soilless cultures especially should be handled thoughtfully. A fraction of the nutrients administered, more than 25-30%, is doomed to be lost in an open system, and the resulting ecological risk is accompanied with increasing costs of the production. Experiments have been conducted with the purpose of estimate the amount of nutrients involved. According to the results, as a mean, 30-80 per cent of the main nutrients was utilised. The rate of nutrient utilisation is influenced by the plant species involved as well as by the circumstances of production. One of its most important components is the irrigation, which determines the amount of overflow and of its salt content.

  • The application of A HEAT SUM MODEL for the budburst of sour cherry varieties grown at Újfehértó
    105-112.
    Views:
    320

    Experiences of the last decades showed univocally that the climatic changes, especially the warming up, influenced clearly the phenology, i.e. speed of growth and development of plants. To check the effects, the phenological studies became a topic of special interest. Our research has been performed at Újfehértó, the Research Institute of Fruit Growing and Extension, where the respective database accumulated observations during the period 1984–2005, where the meteorological data as well as the parallel phenological diary referring to the varieties ’Újfehértói fürtös’, ’Kántorjánosi’ and ’Debreceni bôtermô’ during the period 1984–1991 have been utilised. The method of calculating the sum of daily mean temperatures, “degree days”, is based on the observation that the plants are able to utilise cumulatively – in growth and development – the temperature above a set basic temperature. Our phenology model examined the correlation between the sum of degree days and the date of sprouting (budburst). The basic temperature has been determined by optimization, above which (threshold temperature) the accumulation of daily means was most active, or alternatively, below which the daily means are most sensitively expressed in the phenology. The model has been extended to the calculation of the end of rest period (endodormancy) – by optimization as well. Our phenology model will be suitable for two main purposes: for estimating the time of budburst for the Hungarian region during the next decades calculated on the basis of regionally downscaled climate models; on the other hand, by applying our model, the risk of damage caused by spring frosts could be estimated more exactly than earlier.

  • Utilisation of data raised in blooming phenology of fruit trees for the choice of pollinisers of plum and apricot varieties
    35-41.
    Views:
    359

    Information concerning the blooming time of stone fruit varieties is, first of all, an important condition of finding suitable pollinisers securing adequate fruit set. For that purpose, varieties are assigned to blooming-time-groups. Depending on the number (3 or 5) of the groups, i.e. the length of intervals separating the groups established, pollenisers are to be chosen for self-incompatible and partially self-fertile varieties belonging to the same blooming-time-group. The mutually most overlapping blooming periods of the respective varieties should be found by raising data of their blooming phenology, i.e. dynamics, which is compared by drawing their phenograms and calculating blooming (V) indices. Variety combinations have to be checked, however, concerning mutual fertility relations of the respective pairs of varieties. That is most important in the case of Japanese plums because of the abundant incompatible combinations. Synchronous blooming has been determined by assigning the varieties to blooming-time-groups, or comparing overlaps of blooming phenograms, or by blooming (V) indices. Synchronous blooming phenology has been studied in European plum varieties (111 varietiy combinations) Japanese plums (156 variety combinations) and apricots (153 variety combinations) under Hungarian conditions, over several seasons. In determining overlaps, the less favourable season has been considered as decisive. Polliniser combinations have been chosen with at least 70% synchronous blooming. Blooming time of varieties is an important part of the variety descriptions. Blooming dates may serve also for the estimations of frost risk or security of yield.