Search

Published After
Published Before

Search Results

  • 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.

  • Spatial and temporal variation of extremely low minimum temperatures in Hungary during the period between 1951 and 2010
    75-80.
    Views:
    229

    For this study, data of 16 meteorological stations have been processed over a period of 60 years with the purpose to reveal the spatial and temporal structure of the frequencies of absolute extreme minima in Hungary with special reference to the surmised global rise of temperatures on a worldwide scale. In the main areas of fruit growing, the monthly or seasonal absolute temperature maxima and minima are presented during the 60 year-long period and projected on the geographical map. For the main fruit- and vegetable growing regions the probability of winter- and late frosts is of prime interest. The time series of extreme temperatures though did not prove signifi cant changes over the period observed, but the information upon changes and their tendencies is a precious tool being utilised in planning, choice of adequate varieties for a longer period of time in the future. The deleterious winter frosts experienced in fruit production is not a consequence of a sole drop to a minimum temperature, but of an earlier period of mild temperatures during the winter, which sensibilised the trees. Frequent and extreme variations of temperatures may cause troubles at any time during the year and reduce the yields conspicuously. We ought to get familiar with the hazards of our climate and fi nd optimal solutions to mitigate the damages expected. The seasonal and monthly distribution projected on the geographical map we can follow up also the spatial relations and the signifi cance of their occurrence. Coeffi cients of variation between meteorological happenings at different localities facilitate the calculation of the probability of risks on the surrounding areas.

  • Apple powdery mildew caused by Podosphaera leucotricha: some aspects of biology
    19-23.
    Views:
    389

    Apple powdery mildew (Podoshphaera leucorticha) occurs wherever apples are grown. One of the most important fungal disease of apple which causing severe econimic loss on susceptible apple cultivars. Biology of the pathogen is widely investigated all over the world in the past 100 years. In this review, a summary from this enormous research is made for biology of apple powdery mildew in the following aspects: geographical distribution, morphology, taxonomy of the causal agent, symptoms, host susceptibility, resistance durability and disease cycle.

  • Apple powdery mildew caused by Podosphaera leucotricha: some important features of biology and epidemiology
    45-51.
    Views:
    433

    In this review, some important features of biology and epidemiology are summarised for apple powdery mildew (Podosphaera leucotricha). In the first part of the review, the geographical distribution or the pathogen are discussed, then the morphology and taxonomy of the causal organism are described. Disease symptoms or apple powdery mildew are also shown and then host susceptibility/resistance is discussed in relation to durability of resistance. In the second part of this review, the general disease cycle of powdery mildew on apple are demonstrated and some basic features of powdery mildew epidemiology (such response of the pathogen to temperature, relative humidity, and rain as well as spore production, spore dispersal, diurnal patterns and temporal dynamics of the pathogen/disease) are also given on apple host.

  • S-locus genotyping on stone fruits in Hungary: a review of the most recent achievements
    39-43.
    Views:
    216

    Central Europe can be taken as a geographical and historical connection zone between the western growing countries and Asian gene centres of Prunus tree fruits. The determination of the S-genotype of stone fruit (mainly almond, plum, cherries and apricot) cultivars and landraces has both practical and theoretical significance. Our group has allocated complete S-genotypes for more than 200 cultivars and selections of almond, Japanese plum, sweet cherry and apricot. Among Eastern European almond cultivars, two novel cross-incompatibility groups (CIGs) were identified. S-alleles of a related species were also shown in P. dulcis accessions; a fact seems to be indicative of introgressive hybridization. Our results with Japanese plum clarified and harmonized two different allele nomenclatures and formed a basis for intensive international studies. In apricot, a total of 13 new S-alleles were identified from Eastern European and Asian accessions. Many Turkish and North African cultivars were classified into new CIGs, III–XVII. Results suggest that the mutation rendering apricot self-compatible might have occurred somewhere in south-east of Turkey and we were successful to confirm the presumed Irano-Caucasian origin of North African apricots based on the geographical distribution of S-alleles. In sweet cherry, new alleles have been identified and characterized from Turkish cultivars and selections. In addition, wild sweet cherry and sour cherry S-alleles were also shown indicating a a broader gene pool in Turkey as compared with international cultivars. We also used S-genotype information of Ukrainian sweet cherry cultivars to design crosses in a functional breeding program. Our results exhibit an increased number of S-alleles in tree fruit accessions native to the regions from Eastern Europe to Central Asia, which can be used to develop S-genotyping methods, to assist cultivation and draw inferences for crop evolution.

  • Ecological diversity of Hungarian medicinal and aromatic plant flora and its regional consequences
    10-19.
    Views:
    180

    During the last century the medicinal and aromatic plant sector has became a successful part of the Hungarian Agriculture. Some of the national products have been accepted as a special Hungarian ones ("Hungaricum"), evaluated on the world market, respectfully. By the estimates the cultivation area of medicinal and aromatic plants increased up to 37,000-42,000 hectares and considerable amount — about 10, 000-15, 000 tonnes of dry biomass — are produced by utilisation of Hungarian indigenous flora, year by year.

    In the present work ecological requirements of 97 collected and 55 cultivated medicinal and aromatic plants are characterised. Based on the analysis of -Ts (temperature regime values) about 63 per cent of cultivated species came from Submediterranean and Mediterranean type of habitat, originally, while the majority of collected plants (61.8 per cent of them) prefer the deciduous forest conditions. The differences between collected and cultivated species are appreciable too, if the distributions of their characteristic water regime ('W' values) are compared. The majority of cultivated species require dry (moderate dry) and fresh (moderate fresh) habitats, while the amplitude of water requirement of collected species is much more wide-ranging.

    The regional specialisation of Hungary according to production of medicinal and aromatic plants is known from the beginnings of the 20th century. As a result of spontaneous process seven well-defined production areas were developed. The relationship between regions, their climatic conditions and spectrum of species produced there are analysed.

     

  • Virus and virus-like diseases of grapevine in Hungary
    25-36.
    Views:
    283

    Viruses and viroids are submicroscopic infectious particles which can cause disease symptoms on grapevine. These parasites are depending completely on the energy metabolism of the plant cell. To enter the host cell plant viruses depend on injuries or on transmission via invertebrates (insects, nematodes, etc.). Viruses are classified by many characters including particle morphology, host range and information content of the genome. At present about 70 viruses including 7 viroids infecting grapevine are known. In single or mixed infections they are potentially detrimental to the quality and quantity of grape production in any growing area of the world. Some viruses can cause severe economic damage in vineyards. In Hungary many important viruses and viroids have been detected in grape. This review summarises characteristics of viruses and the results of detection and characterization of virus and virus like diseases of grapevine in Hungary. The identification of the causal agent, its transmission, geographical distribution and the development of the diagnostic methods are also discussed.

  • Some biological features of cherry leaf spot (Blumeriella jaapii) with special reference to cultivar susceptibility
    91-93.
    Views:
    612

    In this review, some important features of biology are summarised for cherry leaf spot (Blumeriella jaapii). In the first part of the review, the geographical distribution of the pathogen and the causal organism are described. Disease symptoms and disease cycle of cherry leaf spot are also shown. Special attention is given to hosts and then several cherry cultivars.are described in relation to their susceptibility to cherry leaf spot.