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  • Precision geoinformatical system of the pear gene-collection orchard
    43-50.
    Views:
    217

    The principle task of the sustainable development is the preservation of the genetic variety, which is similar challenge in the horticulture regarding the sublimation of fruit species. The breeders of the traditional fruit strains give stock to the sustenance diversity of the agro-environment on the species and landscape level. In 2009, hyperspectral images have been taken by AISA Dual sensors from the pear gene pool in Újfehértó, Hungary. The hyperspectral data cube (in the wavelength range of 400-2500 nm, with 1.5 m ground resolution) ensured possibility to make the spectral library of pear species. In the course of the simultaneously field work the spatial position and individual extent of all pear trees was defined to set up a detailed GIS data base. The water stress sensitivity of single species and the descriptive spectral curves were determined with common evaluation of the spectral and spatial data. Based on the unique methodology processing and the hyperspectral data base suitable strains can be chosen for agro-environment and let take adaptive stocks regarding climate change into the genetic grafting work. Furthermore we could determine and map the sparsely species in the region with the help of the hyperspectral data.

  • Role of wholesale markets in fresh fruit and vegetable distribution in Hungary
    46-50.
    Views:
    137

    The primer function of fruit and vegetable wholesale markets — which was the physical concentration of supply and demand previously — is changing gradually as consumer habits change and logistics functions (e.g. product manipulation, redistribution without the physical presence of the product) become more important with the technical development. Mainly individual growers sell their product to retailers at the Hungarian regional producers' markets and the Budapest Wholesale market on NagykOrosi Street, which is the largest wholesale market in Hungary regarding area, produce arrival and turnover. Parallel to the establishment of Producers' Organisations (P0) their market presence should be urged in selling their produce and also in ownership — and decision-making procedure — of the markets. The produce auction system and the on-line sales experiences of New Jersey State (USA) can contribute to the investigation of development possibilities and realization of development of Hungarian wholesale markets.

     

  • Nutritional quality, fruit shape and relationships among exotic and local Capsicum pepper genotypes in Uganda
    33-39.
    Views:
    336

    Twenty-one hot pepper genotypes comprising of local (15) and exotic (6) types (C. annuum, C. frutescens and C. chinense) were characterized for selected fruit traits after propagation in a glasshouse at the Makerere University Agricultural Research Institute Kabanyolo in Central Uganda using a completely randomized design with three replicates. Ripe fruits were harvested and analyzed; traits evaluated were all significantly different at P<0.05 with variations in quality attributes. The genotype OHA-B305-10 had the highest ascorbic acid content (128.86 mg/100 g) and is recommended for improvement of both local and exotic genotypes targeting the fresh market. Genotypes CAP0408-12 and UG2 WE0511-22, with highest total soluble solids (16.17 ºBrix) and dry matter content (28.59%), respectively should be used in improvements for industrial use or processing to products such as chilli powder or flakes. BRS-M205-04 with highest titratable acidity (1.04%) can be used in enhancing shelf life of genotypes with low titratable acids as well as for the fresh market. In spite of the intraspecific relationships among genotypes, significant differences were observed in their quantitative traits. These genotypes will, therefore, be useful in improving the quality of hot pepper fruit in Uganda.

  • Prevention and protection technologies – How do the growers get ready for climate change?
    67-69.
    Views:
    286

    Within the sector of fruit growing, climate change related tasks cover a rather wide range of activities. According to what is claimed by the literature, all decisions impacting the sector should be made conformably with climate change in order to advance an increase in yield security. This, regardless of the impacts of climate change, is also one of the key questions in fruit growing. Regarding protection against extreme weather events, in addition to technological and technical elements, the level of importance assumed by farmers for the abovementioned protection techniques as well as the type and extent they intend to use of this in practice are also worth of studying. This ongoing research beginning in 2009 mainly focuses on studying the opinions of fruit farmers making up the target group for this analysis. The questionnaire survey primarily intends to study their knowledge on the definition of climate change as reactivity to unfavourable weather events occurring in the growing. The study aims at providing a realistic view on the fruit-farmers’ knowledge on climate change and on how technological elements, new technical solutions applicable to mitigate damage are used during production.

  • Epidemiological survey of Xanthomonas arboricola pv. juglandis and Gnomonia leptostyla on natural population of walnut (Juglans regia) in eastern Transylvania
    7-9.
    Views:
    2099

    In Romania, walnut Juglans regia L. is an important fruit crop, although most of the fruit production comes from non-grafted walnut trees, which are natural hybrids. Breeding programs have been launched during last 30 years to develop new cultivars with uniform fruit quality. In addition, foreign cultivars have been introduced and tested to establish a valuable walnut genepool. To improve the present assortment of generative rootstocks in walnut and to examine the infestation level, a long term survey was carried out in Eastern Transylvania. The main physical characteristics of fruits and its variation to the infestation level were considered. The cumulative distribution of Xanthomonas arboricola pv. juglandis and Gnomonia leptostyla were relatively low and the maximum value was around 15%. The highest infestation of husk with X. arboricola pv. juglandis was observed for roundish forms and differences were statistically significant comparing with other phenotypes. Infestation with G. leptostyla was similar for roundish, elliptic and thwarting egg-shaped phenotypes, while the husk infestation for egg-shaped phenotypes was not observed. The walnut population studied in our experiment can be considered as a genetically valuable population. More than 20% of them have upper class quality fruits with at least or more than 50% of nutmeat. Do to the large scale climate variation in Eastern Transylvania and the high humidity favourable for pathogen infestations, these population can be considered resistant and well adapted to abiotic and biotic factors.

  • Propagation of plum rootstocks by hardwood cuttings
    23-28.
    Views:
    131

    Vegetative propagation by hardwood cuttings is a very simple and cheap method for production of plum rootstocks. The aim of this study was to examine if this propagation technique is suitable for practice of three plum rootstocks and find the time or period when the percent of rooted cuttings is maximal. Based on our results, hardwood cuttings of the rootstocks tested have the rooting potential acceptable for practice, however, for Fehér besztercei in the previous literature leafy cuttings are recommended. Fehér besztercei reached 74.0% rooting, cuttings of Sainte Julien GF 655/2 rooted in as high percentage as 78.3%, and Marianna GF 8-1 had 88.3% rooted cuttings. Rooting potential of hardwood cuttings depends on more factors, one of them can be their dissimilar sensitivity for the diverse environmental circumstances at the different propagating dates, affecting through the internal biochemical changes that can be in relation with the differences in their dormancy.

    The cuttings of Marianna GF 8-1 take root easily, but in some years the conditions were less favourable for reaching maximal rooting. For taking cuttings the period from the beginning of October until December was optimal. For Fehér besztercei the optimal date of cutting collection was around the end of October, but in some years the rooting in the middle of December was also high. Sainte Julien GF 655/2 definitely rooted best in October. The treatments with different IBA concentrations in two years affected differently the rooting percentage. The rooting of Marianna GF 8-1 and Sainte Julien GF 655/2 is barely influenced by the different hormone dose in both years. Hardwood cuttings of Fehér besztercei rooted definitely better when treated with 2000 ppm IBA in comparison to untreated ones, while in 2001-2002 there was no difference between 2000 and 4000 ppm.

     


     

  • Simultaneous impact of the different water supply and year type on processing tomato yield
    79-81.
    Views:
    198

    A two year (2008 and 2009) open field experiment was conducted to study the effect of irrigation on the yield parameters and fruit components of processing tomato. Two different treatments were applied: regularly irrigated (RI), irrigation cut-off 30 days before harvest (CO), compared with unirrigated control (RF). The optimal water supply was calculated from average daily temperature. The aims of the study were to investigate the effect of different water supply on yield quantity. The regularly irrigated plant stands gave significantly higher yield, and unirrigated plants showed yield loss.Water supply had strong positive (R2=0.81) effect on marketable yield and average fruit weight (R2=0.78). Linear regression showed, that 46.5 mm more water supply caused 10 t/ha more marketable yield, and 13.4 mm more water supply caused 1 g more in the average fruit weight. The irrigation increased the Brix yield as well.

  • Freeze Susceptibility of Fruit Buds in 67 Apple cultivars in Hungary
    29-35.
    Views:
    131

    Frost damage is one of the most important risks of apple production. Outstanding importance has been attributed to the frost resistance of flower-buds as decisive sites of fruit production. Browning of plants parts and tissues exposed to natural weather adversities are considered as effects of frost. In Hungary, frost damage on flower buds of both the market and new cultivars has not been assessed earlier. Observations referring to the consequences of frost damages of over four critical years, marked by their peculiar winter and spring frost hazards. Parallel observations have been made in four sites of the growing area in the Great-Plain region. 67 apple cultivars have been assessed. Each cultivar was represented by 3 trees, which were sampled at about 1-1.5 m height over ground, where the buds or inflorescences were picked for the purpose to assess the injury. The buds and flowers are cut longitudinally and rated visually according to the extent of browning of the organs and tissues. Susceptibility of different organs of the flower (pistils and anthers) were rated separately. According to our results, most resistant to spring frosts are the following cultivars: 'Gloster', 'Granny Smith' and appreciable tolerance is attributed in 'Gala' and 'Jonathan' with derivatives. Preliminary results that among the scab resistant cultivars, `Baujade', 'Rewena', 'Liberty', `Resi' and 'Renora' are rather frost resistant. Information, lacking hitherto, is obtained upon 'Reka' and 'Reglindis' as for their increased susceptibility.

  • Blooming phenology and fertility of sour cherry cultivars selected in Hungary
    33-37.
    Views:
    184

    Experiments were conducted during the period between 1972 and 2002 at three sites in Hungary. At Érd 97, Helvetia 10, and Újfehértó, 3 cultivars were studied in variety collections. Observations were made on the blooming phenology (start, main time, end and length of the bloom period), on the blooming dynamics (the rate of the open flowers counted every day), on the receptivity of sexual organs, on the fruit set following self- and open-pollination and on the effect of association of varieties in the orchards (choice, rate and placement of pollinisers).

    Based on the results the rate of the overlap of the blooming times were calculated and varieties were assigned into five bloom time groups according to their main bloom. Self-fertility conditioned by natural self pollination was studied and good pollinisers were chosen (sweet, sour and duke cherry varieties) for the self-sterile and partially self-fertile varieties.

    The necessity of bee pollination was proved by different pollination methods: natural self-pollination, artificial self-pollination, open pollination. Summary: Experiments were conducted during the period between 1972 and 2002 at three sites in Hungary. At Érd 97, Helvetia 10, and Újfehértó, 3 cultivars were studied in variety collections. Observations were made on the flowering phenology (start, main time, end and length of the bloom period), on the flowering dynamics (the rate of the open flowers counted every day), on the receptivity of sexual organs, on the fruit set following self- and open-pollination and on the effect of association of varieties in the orchards (choice, rate and placement of pollinisers).

  • Epidemiology of brown rot on two apple cultivars in an organic apple orchard
    49-52.
    Views:
    186

    In a two-year-study, the temporal development of brown rot (Monilinia fructigena) on fruits was analysed in an organic apple orchard on an early (Prima) and one late (Idared) maturing cultivars at Debrecen-Józsa in Hungary. Out of five mathematical functions (linear, exponential, three-parameter logistic, Gompertz, Bertalanffy-Mitscherlich), the three-parameter logistic function gave the best fit to brown rot incidence of all cultivars in both years. Disease progress started at the end of June for cv. Prima and at the end of July for cv. Idared, then disease increased continuously from 6-8 weeks up to harvest in all cultivars. Descriptive disease variates derived from the three-parameter logistic function were used to analyse disease progress. These were: Yf, the final disease incidence; Y55, fruit incidence at day 55; Y95, fruit incidence at day 95; b and q, the relative and the absolute rate of disease progress, respectively; T1.5, the time when disease incidence reaches 1.5 %; M, the inflection point and AUDPC, area under disease progress curve. Descriptive disease variates were significantly different (P<0.05) for cv. Prima compared to cv. Idared, except for the relative and absolute rate of disease increase, b and q, respectively. The largest differences among cultivars were in the values of the AUDPC. Disease progress curves and descriptive disease variates were presented and the practical implications of the results were discussed.

  • Phyl-Gold: a product to diminish russeting of 'Golden Delicious' apples
    131-133.
    Views:
    134

    Producing high quality apples in mature trees of the cv. 'Golden Delicious' is rather difficult because of the russeting of it's fruits, especially in seasons of high relative humidity and/or wetness.

    Earlier experiments proved the possibility to decrease russeting by treatments of GA4.7 during a period after petal fall.

    Phyl-Gold, a product of Phylaxia Co. (ai. 10 g1-1 GA4.7) was applied to inhibit russet formation in fruit skin of 'Golden Delicious' apples. Four consecutive sprays were carried out (with 10 ppm a.i.) in weekly intervals, starting at petal fall and tank-mixed with the current pesticides of the plant protection program.

    Due to the GA4.7 application the russet formation decreased at a rate of economical importance. As for the side-effects of treatments, fruit set was reduced slightly in trees treated, however, there was no consequent influence on return bloom.

     

  • Importance of orchard floor management in organic fruit growing (nutritional aspects)
    61-67.
    Views:
    386

    Worldwide research goals and concerns are to soil conservation and improve. This conception is mostly actual in horticulture where the numbers of high-density plantings are continuously increasing. High-density orchards cause more intensive nutrient and water uptake. So that the preservation of soil moisture and nutrient level are key factors in qualified fruit growing. On the other hand due to the climatic changes the water supply of trees will be satisfied among worse conditions than some decades ago. Appearance of water supply problems and water stress is increased in organic growing, where the number of corrections is limited anyway. Furthermore, floor management is a successful tool in weed management which causes many problems for organic growers due to the prohibition of synthetic herbicides. This paper will mainly focus on the nutritional aspects of methods of orchard floor management for growers adopting organic fruit management to make their production profitable.

  • Antioxidant capacity, C-vitamin and anthocyanils content in the fruits of elderberry (Sambucus nigra L.) types
    77-79.
    Views:
    156

    : Elderberry used to be a common medicinal plant since long. Its ripe fruit and inflorescence has been collected. Cultivation however, started in Hungary recently, with the early 90-es. Initially, has been planted, the 'Haschberg' cultivar. Our Department started first with the selection of favourable genotypes in the Hungarian spontaneous populations of the species, we aimed to find clones, which are earlier ripening than 'Haschberg', moreover, superior in any of the agronomical or quality traits. Present study deals with 19 new selected clones by their content of vitamin-C, anthocyanins and their antioxidant capacity. Environmental stresses are inducing, increased, accumulation of free radicals in living organisms. To evoid the harmful effects of the free radicals, we need to consume antioxidant compounds (flavonoids, anthocyanins, vitamins, etc.) In the literature there are quite a few references related to the anthocyanins and antioxidants of the elderberry. Measurements prove that substantial differences exist among the population of the species as for the content and quality of those compounds. In anthocyanin content, the difference between the highest and lowest values was 3000 mg/I, whereas in antioxidant content this value was 6001.1M. Those types, which contained less anthocyanin (<5000 mg/I), produced lower antioxidant capacity, whereas the highest anthocyanin content was associated with the strongest antioxidant activity. C-vitamin content varied between 36.5 and 96.4 mg/100g. These values provide daily human requirements by their consumption. Summing up all parameters, examined the best type was Cinkota 1.

  • Comparative analysis of peach and nectarine cultivars based on their ecological and biological indicators
    7-26.
    Views:
    357

    Natural conditions other than the ecological conditions of the Chinese gene center (as 34-38° latitude and 600 to 2400 m above sea level), mainly dry subtropical, i.e. Mediterranean effects, facilitated the development of new forms and varieties (Scorza & Okie, 1991; Faust & Timon, 1995). Probably the primary cause of nectarines, this could also be the primary cause of mutations (probably about 2000 years ago) (Roach, 1985; Surányi, 1985). During the long domestication of peaches, its natural occurrence increased, which was greatly enhanced by its ecological and mutational ability and the organoleptical values of its fruit (Hedrick, 1917; Roach, 1985; Scorza & Okie, 1991; Faust et al., 2011). Through the Ellenberg-Borhidi model and its refinement, the author has demonstrated the suitability of peaches in a broad climate zone based on the relative ecological and biological values of 700 varieties. Among the varieties, clone cultivars and hybrids were Hungarian selected and crossed form, because the diverse environmental conditions of the Carpathian Basin and the past and present size of cultivation were representative (Faust & Timon, 1995; Timon, 2000). It can be concluded from the present relative ecological data that the average standard deviation is below 12% for both peach and nectarine varieties, but the relative biological values were very different. Comparison of cultivars or classical (downy) peaches (n = 562) and nectarines (n = 138) in terms of environmental values confirmed the difference in heat demand and salt tolerance of the two groups of varieties. The pictures of the paper also demonstrated the rich diversity of this fruit species, and after analyzing the apricot and plum varieties (Surányi 2014, 2018), the peculiarities of the relative ecological and biological values of peaches were confirmed.

  • Composition and sensory properties of sour cherry cultivars
    19-23.
    Views:
    356

    Fruits of different sour cherry varieties cultivated, in 2008 and 2009, under organic farming and integrated cultivation conditions were analysed for their quality attributes, antioxidant activity and subjected to sensory evaluation.. Average size, weight, soluble solids, titratable acidity, total polyphenols, free radical scavenging capacity expressed as Trolox equivalent (TEAC), copper and zinc were determined in freshly harvested fruits. The obtained results indicated that, the principal component analysis can separate and distinguish the seasons of fruit production. The farming system seemed to have slight effect on quality the fruit as compared to varietal factors (genotypes). However, the total polyphenol content was uniformly less in 2009. Total polyphenols and free radical scavenging activity were significantly higher in Bosnian type sour cherries, and outstanding in Amarelle type cultivar ‘Pipacs’. There was no statistically significant difference between the sensory properties of cultivars tested by panels, except the case of ‘Pipacs’. The organolaptic investigation showed marked preference to the fruits of Eva and Petri cultivars.

  • Pomology of gene resources bearing resistance to Erwinia amylovora
    29-33.
    Views:
    128

    The ecological farming and an increasing demand for healthy fruits free from chemical residuals necessitated the reevaluation of the existing cultivars and breeding suitable cultivars for the new requirements. We have gathered the old genotypes known in the Carpathian Basin, and we have selected the most suitable ones according to fruit quality and resistance to diseases in the last fifteen years. The main aim was the selection of resistant genotypes against fire blight and powdery mildew as gene sources for our breeding program. On the other hand, we consider the best quality traditional cultivars as extensive landscape elements (wayside tree rows or extensive squash producing plantations).

    During the pathological evaluation 'Szemes alma', 'Pónyik', 'Sikulai', 'Tordai piros 'cavil' and 'Szabadkai szercsika' cultivars proved to be good resistance sources (due to their outstanding resistance to fire blight). The latter four cultivars are not susceptible even to fungal diseases, and their quality is also acceptable so those are commendable for ecological farming or for renewing the sparse orchards. According to fruit quality and low susceptibility to diseases 'Batul' and 'Vilmos renet' can also be offered for extensive organic production.

    We have made original or renewed pomological descriptions of the selected cultivars, and we also publish their characters according to the terms of UPOV TG/14/8 based on to our evaluations.

  • The brown rot fungi of fruit crops (Monilinia spp.): I. Important features of their biology (Review paper)
    23-36.
    Views:
    205

    The brown rot fungi of fruit crops (Monilinia spp.): Important features of their biology (Review paper)

  • Honeybee (Apis mellifera L.) visitation at the flowers of quince cultivars (Cydonia oblonga Mill.)
    95-102.
    Views:
    167

    Studies were made on the bee visitation of 6 quince cultivars and on the foraging behaviour of honeybees at quince flowers for 3 consecutive years. The bee visitation was highly intense because both the plantation and its surrounding was overpopulated by honeybee colonies. Some 5.5 bee visits were counted in average at 50 opening quince flowers in 10 minutes and some 9.7 flowers were visited of the 50 ones observed meanwhile. This equals some 7 bee visits per flower per day per in good weather. Bee visitation, however, was variable and it was greatly different in the three consecutive years with fairly favourable weather. Some cultivars tended to be more and others less visited by honeybees than the others but these differences were not consequent at each occasion. No consequent relationship between the weather and the bee visitation of quince trees could be recognised. It was concluded that .other factors were responsible for the variable nature of the bee activity at quince. Most honeybees tended to collect pollen (51.6% in average for the 3 years) and usually much less gathered for nectar only (19.9%), and the rest of them were mixed behaviour foragers gathering for both (28.5%). There were some slight differences in the foraging behaviour of honeybees at some cultivars but these differences were not always consequent in consecutive years. Also the nectar production of flowers failed to affect the bee visitation and the foraging behaviour of honeybees definitely. For the variable nature of bee visitation and bee behaviour at quince flowers, supplementary pollination is needed to achieve as high set of fruits as high is required to a good crop at quince (at least 20-25% because the flower density is low of this fruit tree species). Since the intensity of bee visitation at the flowers is the only reliable estimate of the necessity of supplementary bee pollination further research is needed to explore the relationship between the number of honeybee visits and the consequent fruit set at quince.

     

  • Toxicity of fungicides to honey bees (Hymenoptera: Apidae) and their effects on bee foraging behavior, pollen viability and fruit set on blooming apples and pears
    96-98.
    Views:
    179

    Fungicides fosetyl-AL, triadimefon, dodine, mycobutanil and fenarimol were tested for honey bee (Apis mellifera L.) mortality and effect on bee foraging, pollen viability and fruit set in blooming apple and pear. None of the materials were toxic to honey bees or reduced pollen gemination or fruit set.

     

  • Climatic indicators regarding the rest period of sour cherry
    49-52.
    Views:
    204

    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.

  • Effect of variety and cultivation technology on phenols and antioxidant activity of sweet and sour cherry
    59-61.
    Views:
    361

    The goal of the present work was to compare different sweet and sour cherry cultivars and cultivation methods (bio/integrated) with respect to polyphenol content and antioxidant activity. The concentration of total polyphenols ranged between 880–1050 mg kg-1 of fresh fruit, whereas antioxidant activity expressed as TEAC was found to be between 5.4 and 10.3 mmol kg-1 for the sweet cherry cultivars examined. In case of sour cherry the level of polyphenols ranged between 1283 and 3490 mg/kg fresh edible part of the fruit. Antioxidant activity was recorded between 15–32 mmol kg-1 for the different sour cherry cultivars included in this work. After one-month storage at low temperature, the total phenols and antioxidant activity decreased by 2–40% in the sour cherry cultivars studied. The anthocyanin content in cherry cultivars was less (131–312 mg kg-1) than the135–1893 mg kg-1 found in sour cherries. Anthocyanin level was higher in samples produced under organic farming conditions than in those produced with integrated cultivation.

  • First results of varios sour cherry cultivar on Oblacsinska as interstocks and Prunus mahaleb rootstocks
    87-90.
    Views:
    331

    At the experiment orchard of the Fruit Research and Extension Institute, Újfehértó, Hungary in spring 2000 a trial was designed included: Erdi bőtermő, Debreceni bőtermő, and Csengődi sour cherry (Prunus avium L) cultivars which were budded at 1999 on Oblacsinska sour cherry (as a dwarf inter stock), which had been budded on Prunus mahaleb seedlings at 1998 with the aim to investigate the dwarfing effects of Oblacsinska sour cherry cultivars on scion cultivars. Trees of each cultivar directly on Prunus mahaleb seedling, severd as controls. Use of Oblacsinska as an interstock reduced the rootstock trunk diameter. Trees of Debreceni bőtermő, and Cseng6di sour cherry cultivars with Oblacsinska interstock were smaller than similar trees grafted directly onto Prunus mahaleb as a rootstock. Trees of Erdi bőtermő grafted on Oblacsinska interstock which buded on Prunus mahaleb were the smallest. Growth of the trees was reduced also by using of the Oblacsinszka as interstock for other examined cultivars.

  • Experimental approach in apple tree nutrition
    9-13.
    Views:
    125

    Authors present synthesis of experimental work, performed in the last decades, for better understanding nutritional behaviour of apple trees and related problems in fruit quality. There were evidences supporting possible deteriorating role of potassium in feeble physiological status of apples, if applied in excess. More intensive studies proved that higher potassium uptake into leaves and fruits might be also the result of increased sink power of individual fruits. Nevertheless early senescence of apples during storage and also sensibility to bitter pit were successfully related to the increased sink power of fruits, casual relations in excessive NPK fertilization, although increase in sink power need further investigations. Impaired weather conditions during early development of fruits, hostile orchard practices in pruning, thinning, irrigation and also unskilled application of growth regulators may also contribute in the enhancement of sink power and in weakened physiological status of apple fruits.

  • Spatial and temporal variation of extremely low minimum temperatures in Hungary during the period between 1951 and 2010
    75-80.
    Views:
    205

    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.

  • Determination of auxine content of soft wood cutted `Marianna GF8/1' (Prunus cerasifera x P. munsoniana) by High Performance Liquid Chromatography during rooting period
    67-70.
    Views:
    129

    The content of different auxins of soft-wood cutted plum rootstock 'Marianna GF8/1' (Prunus cerasifera x P. munsoniana) was determined during the rooting period. The level of auxin-concentration (exogenous and endogenous) of basic and intemodal part of cuttings was determined by WATERS HPLC equipment every 7 days during rooting period. The lengths soft wood cuttings were app. 30 cm long. The basal part of shoots were treated with 2000 pg/g concentrated indole-butiryc acid in talcum powder. After treatment the cuttings were placed in propagation green-house under intermittent mist. The plant hormones were extracted by methanol the solution was cleaned by paper-filter, and further cleaned by centrifuge. The effluent was examined by reversed phase High Performance Liquid Chromatography, with WATERS 2487 dual detector at 220 am on Symmetry C18 4,6x 150 column. Recovery and reproducibility assessment indicates good accuracy and acceptable relative standard deviation (RSD) 5%. Linear responses (r20.997) for calibration curve was obtained with IAA, IPA and IBA standard in range, with a limit of quantification of 0.15 g•m1-1. The concentration of IAA, IPA and IBA in the basal part of cuttings were measured, during the rooting period. We proved the external IBA was taken up by the plants. In the plants were found the IBA, and the IAA concentration of IBA treated cuttings was higher, than the untreated one.