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  • A model of full bloom starting date of some white Vitis vinifera L. varieties grown in Helvecia
    21-25.
    Views:
    178

    Grapevine bloom happens between end of May and the middle of June in Hungary. However, climate change in the past decades and the occurring weather anomalies can modi fy this date to a diverse degree. Among the weather factors, the bloom starting dates of grapevine depend mostly on temperature and relative humidity of air. There can be significant differences between North American and East Asian grapevine varieties, and of course, the early and late ripening varieties. ln this approach we investigated the starting dates of bloom between 2000 and 2004 for grapevine varieties grown in Helvecia, as well as the effectiveness of a temperature sum model. The model is based on the widely accepted cumulated heat sum concept, and the optimization was made for the least standard deviation in days as well as on the least average absolute deviation in days and on the least maximum deviation in days. The model is connected directly to a similar model for the budburst date of the same plantings (Hlaszny & ladanyi, 2009). We set the optimum lower base temperature to I 0.45 °C and the upper base temperature to 26 °C. The absolute values of the differences between the observations and the model estimations move between one and six days with an average of 1.81 days

  • Climate change impacts and product lines
    79-83.
    Views:
    225

    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.

  • Climatic indicator analysis of blooming time for sour cherries
    11-16.
    Views:
    209

    County Szabolcs-Szatmár-Bereg produces more than the half of the total sour cherry grown in Hungary. Successful production, i.e. yield, depends largely on weather conditions. Most attention should be paid to the weather during the blooming period, being most decisive from the points of view of quality as well as quantity. In order to predict yields expected, the characterisation of the most important weather parameters is necessary. For that purpose, the database of the Institute of Research and Extension Service for Fruit Growing at Újfehértó Ltd. has been utilised. Records of weather conditions were collected throughout the period 1984-2005, i.e. daily minimum, maximum and mean temperatures (°C), precipitation (mm), and phonological diary of sour cherry varieties ’Újfehértói fürtös’, ’Kántorjánosi’ and ’Debreceni bôtermô’. Data of 7 indicators have been traced: number of frosty days, the absolute minimum temperatures, means of minimum temperatures, number of days when daily means were above 10°C, means of maximum temperatures, number of days without precipitation, and number of days when precipitation was more than 5 mm. On the one hand, we surveyed the changes; on the other hand, estimates have been attempted for the future changes expected during the following decades. The indicators being associated with certain risky events may serve for the prediction of the future recommendations to prevent damages.

  • The application of A HEAT SUM MODEL for the budburst of sour cherry varieties grown at Újfehértó
    105-112.
    Views:
    292

    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.

  • Healthcare values and potential uses of the new Hungarian apple varieties on the basis on fruit analysis
    25-28.
    Views:
    202

    Biological active compounds and valuable characteristics of some apple varieties and candidates were measured in our trials. Fruits of ’Rosmerta’, ’Hesztia’, ’Cordelia’ and ’Artemisz’ are recommended to enrich the Hungarian assortments for fresh consumption and choice of new tastes. Based on examined parameters it can be assumed that novel Hungarian resistant varieties are suitable for juice and fruit concentrate production, and due to high pectin content of their remaining pomace these varieties can be raw material of pectin production as well as they are also suitable for jam production mixed with other fruit species. Furthermore, functional food industrial product having high quality can be produced by using novel resistant varieties because of their high pectin and polyphenol content. Beside of their high market value their suitability for growing among orchard conditions is confi rmed by lower costs of production because of less plant protection treatments.

  • Hail data analyses
    99-103.
    Views:
    125

    Long term data of hail events of three meteorological stations (Budapest, Debrecen and Szeged) were investigated. The hail event frequencies show significant differences in the time period 1901–2000 when the first and the second half of the century are compared. The frequencies of hail events are higher in the first half of the century in case of Debrecen and Szeged while it is higher in the second 50 years for Budapest. None of the frequencies of hail events in between 2001–2008 are significantly higher, though the average of precipitation fell during these events is higher except for Szeged. We have found that the results about the monthly distribution of hail events differ from the ones in the literature; the ratio of hail events is significantly less in the vegetation period.

  • Climatic indicators regarding the rest period of sour cherry
    49-52.
    Views:
    215

    Sour cherry production in the world is increasing gradually. Profitable production, i.e. yield, depends largely on weather conditions. If Hungary wishes to keep up with the most successful countries, attention should be paid to the weather during the dormancy period, being definitely decisive from the points of view of quality as well as quantity. In order to predict the expected risk factors, characterisation of the most important weather parameters is necessary. For that purpose, the database of the Institute of Research and Extension Service for Fruit Growing at Újfehértó Ltd. has been utilised. Records of weather conditions were collected throughout the period 1984-2005, i.e. daily minimum, maximum and mean temperatures (°C), and phenological diary of sour cherry varieties ’Újfehértói fürtös’, ’Kántorjánosi’ and ’Debreceni bôtermô’. For the future expectations study we have used the RegCM3.1 regional climate model with 10 km resolution. Data of 4 indicators have been traced: Average temperatures, Number of days without frost, Maximum length of periods without frost, Maximum length of frosty period. On the one hand, we surveyed the changes; on the other hand, estimates have been attempted for the future changes expected during the following decades.

  • Comparison of pear production areas from yield risk aspect
    25-28.
    Views:
    273

    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.