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• Summer pruning of sweet cherry trees and an inquiry of winter frost damages

  41-44.

  B. Vaszily

  I. Gonda

  M. Soltész

  Views:

  245

  One of the most demanded research projects is the intensification of fruit production. The use of dwarfing stocks is a moderate solution as their effect is scarcely satisfactory. Climatic conditions of Hungary are continental in Eastern Europe, where Atlantic and Mediterranean effects are interacting with the continentals in a kind of basin with characters of its own. Capricious meteorological episodes are often disturbing the security of development and fruiting of trees:
  • winter frosts are damaging the cambium and fruiting structures of trees
  • late spring frosts destroy cambium and flowers
  • early autumn frosts hurt the leaves
  • excessive precipitation impairs the growing fruits
  • drought periods during the summer caused water stress disturbing water husbandry.

  Vigorous stocks still prevail in the practice, and they ought to withstand challenges of weather hazards. The strong vigour of plants delaysthe process of senescence and the tendency of getting bald, and regeneration of plants is a sign of vitality. In present research, the trees have been trained on vigorous Prunus mahaleb stocks. Summer pruning was one of the important tools of intensive growing techniques. They were compared with traditional techniques and with plastic foil protected trees observing the vegetative as well as generative growth of them.

• Development in intensive orchard systems of cherries in Hungary

  76-86.

  K. Hrotkó

  L. Magyar

  G. Simon

  M. Gyeviki

  Views:

  296

  High density central leader systems, the so called "spindle trees" are spreading in intensive stone fruit orchards established for hand picking in Hungary. Results of Brunner (1972, 1990) and Zahn (1967, 1996) inspired the researchers to implement their theories into practice under our climate and special soil conditions. For sweet cherry it is essential to apply an orchard system appropriate for hand picking because of the European market requirements. In intensive sweet cherry orchards two new training and orchard systems are developed and adapted to environmental conditions in Hungary based on previous inventions. The first step of the development is represented by modified Brunner-spindle, which applies the delayed heading of the central leader and the sectorial-double-pruning system from Brunner (1972), resulting intensive orchard of 600-800 trees/ha density, planted on standard vigour rootstocks. Modified Brunner-spindle trees are developed with a central leader and wide-angled branches on it. Light bearing wood is positioned on the central leader and wide-angled branches. During training, shoots for branches are bent or a sectorial double pruning is used. The growth of central leader is reduced by delayed heading, and the strong upright shoots are pinched in summer. Based upon tree size spacing of 5 m between row and 2.5-3 m between trees is recommended, tree height is around 3.5-4 m. This training system is useful for hand-picking; 60-70% of the crop can be harvested from ground. Modified Brunner-spindle is suitable for either standard or moderate vigorous rootstocks. The cherry spindle is an intensive orchard planted with 1250-2300 trees per hectare and it is recommended for sweet and sour cherries on semi dwarf to vigorous rootstocks, depending on soil fertility and quality. Trees are 2.5-3.5 m high, 75-80% of the crop can be harvested from the ground. Permanent basal scaffolds are developed on the basis of the canopy to counteract the stronger terminal growth. The tree is headed only once, after planting, from the following year the central leader grows from the terminal bud. The central leader developed from the terminal bud results moderated growth in the upper parts of the tree head. The strong upright shoots that may develop below the terminal bud are pinched to 3-4 leaves in the summer or removed entirely. The weaker, almost horizontal shoots growing from the central leader form fruiting twigs in the following year if their terminal bud is not removed. Brunner's double pruning is used only once or twice on the permanent basal branches because of its good branching effect. Trials on various rootstocks are running to find optimum spacing and fruiting wood management. The training and pruning guidelines are discussed in the paper. The average crop of bearing years is around 20-30 t/ha depending on site and cultivars. This new system is spreading in Hungary, around 70 ha sweet and sour cherry orchards are trained according to our guidelines.

• A critical evaluation of methods used for S-genotyping: from trees to DNA level

  19-29.

  J. Halász

  A. Hegedűs

  Views:

  175

  Fruit setting behaviour of fruit trees remains to be in the focus of plant breeders and growers. Realizing that most species (cherry, apple, pear etc.) are self-incompatible and certain cultivars are cross-incompatible, mutual fertility properties and their reliable determination are of great interest. This review gives a comprehensive description of all known S-genotyping procedures, i.e. the classical fruit set analysis after open field test crosses; pollen tube growth monitoring with fluorescent microscopy; stylar ribonuclease electrophoresis (using different types of isoelectric focusing and 2-dimension polyacrilamide gel electrophoresis); as well as the most recent polymerase chain reaction based DNA-level analyses and DNA sequencing. The review presented not only gives a compilation of the bases of the methods described but also provides a critical evaluation and a comparative characterization of their applicability.

• A review of the bee pollination research on temperate zone crop plants in the past decade: results and the need of further studies

  7-23.

  P. Benedek

  Views:

  124

  Intense research was made on the pollination of cultivated crop plants in the temperate zone region during the past decade. Some 400 publications appeared on the subject and some additional 150 papers on the effect of pesticides to the most important pollinating insects, the honeybee and the wild bees. Progress of knowledge is discussed in this paper based on the most important publications. Most new results relate to field crops and deciduous fruit species and much less to field vegetables and small fruits. Great effort was taken to improve insect pollination of crops grown under cover. All these are connected to the utilization of the honeybee as a pollinating agent and much less to native or managed wild bees. However, a number of questions arose partly from the results of latest pollination research and partly from practical experiences in commercial plant production. These indicate several research tasks to understand and to solve the problems possibly in the near future. The questions concentrate on the effectiveness of bee visits in the pollination of individual crop plants and their different cultivars and on the reliable estimate of the overall amount of bees as well as on the control of bee density during the flowering periods of crops for optimal, controlled pollination in the changing environment of agricultural crop production.

• Self fertility of pear varieties conditioned by natural self pollination (autogamy)

  110-113.

  J. Nyéki

  M. Soltész

  J. Iváncsics

  Views:

  164

  Authors studied the autofertility depending on natural self pollination (autogamy) in 59 pear cultivars during 4 seasons at three locations with different ecological conditions (Helvetia, Kecskemet-Kisfai, Keszthely). The aim of the experiments was to determine the autogamous tendencies of varieties hitherto unexplored in the Hungarien gene bank, or to check data found in the literature. A total of 42616 isolated pear flowers produced 1.2% fruits with at least one viable seed in each. The 59 varieties observed did not set fruit by autogamy on either of the three sites during the four years of the study. The triploid (3n=51) varieties were entirely self-sterile. According to the highest autogamous fruit set, during the experimental period, the varieties have been assigned to four groups: (1) Entirely auto-incompatible (0% fruit set), (2) auto-incompatible (0.1 to 0.9%), slightly self fertile (1.1 to 5%) and (4) self fertile (5.1 to 10%). According to the number of viable seeds per fruit resulting from autogamy, the varieties are assigned to three groups as (1) low seed content (less than 3 seeds per fruit), medium (3.1 to 5) and (3) high (more than 5 seeds). Thus, the assessment of the number of seeds per fruit resulting from autogamy is indispensable as a proof of the absence of parthenocarpy.

• The role of pruning in the intensification of plum production

  83-86.

  I. Gonda

  Views:

  211

  In an orchard planted in the spring of 1997, four kinds of spacing have been applied (4.0 m x 1.5 m, 4.0 m x 2.0 m, 5.0 m x 2.5 in and 6.0 m x 3.0 m). Four cultivars (‘Cacanska lepotica', Stanley' ‘Bluefre' and ‘President') grafted on Myrobalan rootstock were studied in the experiment aimed to explore the performance of plums under different spacing and training conditions.

  It could be stated that the trees grown on vigorous rootstock are prone to be cultivated much more intensely (smaller tree size, higher tree density) by the consequent use of green pruning technique. The most favourable economic combination (yield and labour costs) was found to be: 4.0 in x 2.0 in and 5.0 x 2.5 in (800-1200 tree/hectare), whereas the most adapted was the cultivar: 'Stanley'.

• Flavonoids, chalcones and phenyl-propanoids in apple and pear flowers

  35-38.

  Gy. Horváth

  A. Farkas

  Gy. L. Szabó

  Views:

  138

  The presence of phloretin-glycosides in the hypanthium and pistil of apple and pear flowers can be verified. Thin layer chromatography is a reliable method for detecting phloretin, gained by acidic hydrolysis. The dominance of phloretin was equally characteristic for flowers in apple (`Sampion', 'Freedom') and pear (Tem^-re Bosc', 'Conference') cultivars treated with various bioregulators (Biomit, Bion 50WG, Regalis), no significant difference could be found visually as compared to control samples. Chlorogenic acid and caffeic acid was detected in all apple and pear samples, rutin was present only in pear, and hyperoside was found only in a few apple samples.

• Evaluation of the growing and fruit bearing characteristics of the ‘Lapins’ sweet cherry cultivar grafted on rootstocks with different vigor

  15-18.

  Á. Csihon

  K. Bicskei

  P. Dremák

  I. Gonda

  Views:

  394

  Sweet cherry is currently considered as a fruit with high interests. The amount of the produced yield is well saleable in the world and also in Hungary year by year, moreover often there is a shortage with the high quality fruits. Researches with the sweet cherry production focus on the intensity growing all over the world, namely the realization of producing with small trees ensuring high quality and quantity. In our examinations ’Lapins’ sweet cherry cultivar was evaluated grafted on rootstocks with different vigor (Gisela 5, Gisela 6, Colt) at the University of Debrecen, Pallag Experimental Station. According to our results trees grafted on Colt rootstock can be described with very low yields due to the excessive high vigor. Trees with Gisela 5 and Gisela 6 rootstocks showed excessive high productivity, as size of the fruits did not reach the required values.

• Susceptibility of European pear cultivars to Venturia pirina Aderh. infection at a variety collection in Hungary

  41-47.

  P. Benedek

  T. Szabó

  Z. Szabó

  J. Nyéki

  Views:

  253

  Field sensitivity of 271 European pear genotypes were evaluated in a large variety collection of pear in Hungary during a nine years survey. Substantial differences were detected in the rate of pear scab infection of leaves and fruits. Some 18 per cent of the inspected genotypes remained completely free of infection even in the years with weather favouring to the disease. On the other hand, 78 % of the inspected genotypes were infected in some or more extent. The rate of infection was generally higher on leaves than on fruits. 18.6 % of the genotypes inspected were tolerant to leaf infection and their majority (81.1 %) were tolerant to fruit infection. Some one fi fth of the genotypes (19.7 %) were highly susceptible to leaf infection but only minor rate of them (2.2 %) were highly susceptible to fruit infection. There were 44 genotypes that could be regarded as tolerant to pear scab leaf and fruit infection under fi eld conditions. Some of these genotypes may be suitable to commercial pear growing with highly reduced chemical control against pear but their yield capacity and fruit quality should be evaluated.

• Effects of indole-3-butyric acid levels and activated charcoal on rooting of in vitro shoots of apple rootstocks

  25-28.

  K. Magyar-Tábori

  J. Dobránszky

  E. Jámbor-Benczúr

  J. Lazányi

  J. Szalai

  A. Ferenczy

  Views:

  249

  Rooting responses of rootstocks cvs. JTE-F1, M. 26 and MM. 106 were studied to different concentration of IBA in root induction media and to presence of activated charcoal in root elongation media. High rooting rate (>90%) could be achieved in cvs. JTE-H and M. 26, while cv. MM. 106 showed weak rooting ability at each IBA level tested. Increasing IBA content depressed the rooting only in cv. M. 26. Presence of activated charcoal decreased considerable the rooting rate in cv. M. 26 and decreased the number of roots in cvs. JTE-H and M. 26. These cultivars developed longer roots on media containing activated charcoal, while cv. MM. 106 did not showed any reaction for it.

• The antioxidant capacity of sea buckthorn (Hippophae rhamnoides L.) berries depends on the genotype and harvest time

  27-29.

  N. Makovics-Zsohár

  A. Hegedűs

  É. Stefanovits-Bányai

  R. Rédei

  N. Papp

  Views:

  247

  Berries of sea buckthorn (Hippophae rhamnoides L.) are characterized by increasing popularity due to their presumable healtheffects. The aim of this study was to compare the antioxidant capacity and total polyphenolic content in the berries of six Hungarian grown sea buckthorn genotypes and characterize the genetic variability in this trait. The harvest time of sea buckthorn berries affects the antioxidant capacity and total phenolic contents in berries of three popular cultivars of German origin. Berries harvested in October had higher antioxidant capacity compared with those harvested one month later. The extent of the difference was genotype-specific. Our analysis revealed a nearly 3-fold difference between the lowest and highest antioxidant capacities of the 6 tested genotypes with ‘Leikora’ showing the highest ferric reducing antioxidant power and total phenolic content. The TEAC values ranged between 1.76 and 3.13 mmol Trolox/100g fresh weight with Pető 1 and ‘Frugana’ having the highest values. The results presented in this study demonstrated that Hippophae rhamnoides berries possess in vitro antioxidant activity strongly determined by genotype but also influenced by harvest time.

• Floral analysis can be use as an early plant analytical tool to diagnose nutritional status of fruit trees?

  23-27.

  P. T. Nagy

  Views:

  191

  A field experiment was conducted in an integrated apple orchard (Malus domestica Borkh.) established on a lowland chernozem soil in East-Hungary, to investigate if flower analysis could be used to diagnose the nutritional status of the trees. In April 2008, during full bloom, flowers and leaves were collected. Leaves were collected again in August, at the standard sampling time from the same trees. The content of nitrogen, phosphorous, potassium, calcium magnesium and boron were measured in flowers and in leaves. Correlation analyses were carried out to establish the relation s between nutrient contents in same and different plant part s. In flowers the following ratio was found between nutrients: N:P: K:Ca:Mg:B -10: l.35:7: 1.7: I :0,02. From result s it was evident that flower as organ contain significant and comparable amount of nutrients like as leaf. The N, K and Ca content were higher in leaves than in flowers at full bloom. The opposite was true for B. The P and Mg content of flower were quite equal with leaf P and Mg at full bloom . All examined nutrients were significantly affected by cultivars both in flowers and leaves. Significant correlation, was found between flower P and leaf P, flower B and leaf B (P=O.O 1) and flower K and leaf K at blooming time (P=0.05). Significant, but weaker correlation was also found between flower K and leaf K and between flower Mg and leaf Mg al JOO days after full bloom (P=0.05). Moreover, strong, but negative correlation was observed between flower B and leaf B at 100 clays after full bloom (P=O.O 1). Within flowers, the strongest positive correlation was found between Mg and B content (P=O.O 1). Strong positive correlations were also recognised between flower K and flower N, Ca and Mg and between N and Ca in the flowers (P=0.01). The strongest correlation was found between K and P in leaves at full bloom (P=O.O 1 ). Strong significant correlation was observed between N and B in the leaves collected at standard sampling time (100 DAFB) (P=0.01). Strong, but negative correlations were found bet ween leaf Mg and leaf P, K and between leaf N and leaf P at 100 days after full bloom (P=O.O 1).

• Rootstocks for Cherries from the Department of Fruit Science Budapest

  63-66.

  K. Hrotkó

  L. Magyar

  Views:

  161

  Cherry rootstock breeding started at the Department of Fruit Science, SSU Budapest by the late 50-s and the activity can be divided into three main groups. In the first stage the activity was focused on collection of native mahaleb cherry (Prunus mahaleb L.) varieties lead by L. Sebők. After evaluation in the nursery and orchard tests there are four promising rootstock cultivars selected from this material: 'Korponay' used as self fertile seed tree, its seedlings are recommended for sour cherries. The mahaleb varieties 'Bogdány' (vigorous), 'Egervár' and 'Magyar' (medium vigour) are propagated by cuttings. The next project has started in 1979 with the aim to select self fertile mahaleb seed trees producing homogeneous seedling populations with reduced vigour. Inbred populations from isolated flowering self fertile trees were produced and planted out in 1980. The inbreeding of 'Korponay' self fertile P. mahaleb variety resulted in specimens with different fruit colour (yellow, red, black), fruit shape and size. From among them self fertile trees were selected with various growth characteristics. Seedlings of that self fertile mother trees (S2 population) were tested in seedbed, they showed homogeneous phenotype characteristics as liners in the nursery. As rootstock of 'Érdi bőtermő' sour cherry in the orchard most of the S2 lines proved to be less vigorous in comparison to SI popuplations. 'Érdi bőtermő' trees budded on certain S2 lines in the orchard are more productive than those on S1 ('Korponay' seedling). Characteristics of the S2 generation as seed tree were studied as well. We expect to get morphologically homogeneous seedling populations with different growth vigour and good productivity in the later inbred generations. In the last couple of decades the research activity concerning ground-cherry and its hybrids resulted in dwarfing rootstocks. Prunus fruticosa Pall. hybrids from the natural flora of Hungary were collected and artificial hybrids were created between P. fruticosa and mahaleb cherry. Most of them are in the initial tests, only one of them is before registration, named 'Prob', which is a dwarf rootstock for sweet cherry. By the screening of new hybrids medium vigorous or semi dwarfing and precocious rootstocks seem to be promising for the cherry industry.

• Variability and differences of growth vigour in the set of 36 genotypes of apricot (Prunus armeniaca L.).

  30-34.

  Z. Vachim

  Views:

  122

  Growth vigour of 36 apricot cultivars and new hybrids grafted on apricot seedling rootstock (Prunus armeniaca L.) was evaluated on the base of measurements of stem girth from the 4¹¹' to the 10th year after planting. There were differences in growth vigour of genotypes under study. In the evaluated set of genotypes the control cultivar 'Veecor may be classified as a genotype with below-average growth vigour. Only four genotypes (^-Reale d'Imola^-, Sanagian ^-Moldavskii krupnoplodnyl and 'LE-2385') were found with significantly higher growth vigour than that of control cultivar 'Veecot' in years of the end of experimental period. Two genotypes (Farmingdale', ^-LE-SE0-24') were found with significantly higher growth vigour only at the beginning of experimental period and one cultivar ('Vivagold^-) with significantly lower growth vigour in the first four years. Genotypes with different growth vigour can be used in further breeding programmes and/or as components inhibiting or supporting the growth in indirect vegetative propagation. Within the whole experimental period, the rank of growth vigour of genotypes practically did not change. This was demonstrated by highly significant or significant coefficients of correlation existing between individual pairs of years (r=0.32+ to r=0.96++). As far as the time difference between years in individual pairs of years was higher, the correlation coefficients were lower. In individual years, variability of growth vigour was relatively low and ranged from 9.83 to 13.64%.

   

• Farm-scale evaluation of two widely used sanitation practices for reducing primary inoculums of apple scab in organic apple production

  15-18.

  I. J. Holb

  A. Rózsa

  F. Abonyi

  Views:

  176

  Effects of two widely used sanitation practices were evaluated at farm-scale level on leaf degradation and primary infection by Venturia inaequalis in an organic apple orchard (Eperjeske) on two apple cultivars (Jonathan and Prima) from 2011 to 2013. The tested sanitation practices were eradication of fallen leaves by collection and disc cultivation. Treatments of eradication of fallen leaves by collection and disc cultivation reduced signifi cantly (P< 0.001) leaf litter density with 70–85 and 40–55%, respectively, compared to untreated plots in both years. Above treatments in the same order reduced spring scab incidence with 40–50, and 10–20%, respectively, compared to untreated plots. Incidence of leaf scab in autumn was not signifi cantly lower (P< 0.05) in the treatments in the years.

• Analyses of Hungarian sour cherry germplasm with simple sequence repeat markers

  27-31.

  Z. György

  T. Szabó

  J. Nyéki

  A. Pedryc

  Views:

  198

  Twenty-four sour cherry cultivars (genotypes), belonging to four cultivar groups were fingerprinted using microsatellite markers. All genotypes have been arisen from the Carpathian basin, which could be secondary gene centre of sour cherry, since its progenitor species, ground cherry and sweet cherry overlap here. Five SSR primer pairs, earlier used for fingerprinting Turkish sour cherry germplasm were tested. None of the five primer pairs showed any polymorphism within the cultivar groups. The primer pairs were able to distinguish between the cultivar groups. The Oblacsinszka and the Cigánymeggy cultivar groups were the most difficult to separate, while the Pándy cultivar group was the most distinguishable.

• Effect of frost damage on leaf macronutrient status of eight apple cultivars in integrated apple orchard in Eastern-Hungary

  37-40.

  P. T. Nagy

  J. Kátai

  J. Nyéki

  Z. Szabó

  Views:

  204

  The year of 2007 was critical for fruit growers in the region of Easter-Hungary. Several orchards were suffered frost damages. Significant frost damage was also happened in the orchard of Tedej Rt., which caused total fruit failure in the orchard. Our study was conducted in the integrated apple orchard (Malus domestics Borkh.) established on a lowland chemozem soil in East-Hungary, to investigate how frost changes the mineral content of different apple species. Leaf samples were collected 100 days after full bloom both in 2006 and 2007. The concentrations of nitrogen, phosphorous, potassium, calcium and magnesium were measured in leaves. The absence of fruits caused a smaller accumulation of nitrogen and magnesium in leaves. Falling down of flowers and fruit sets hindered the translocation of the uptaken phosphorous, potassium and calcium towards fruit sets. Due to fruit failure the vegetative processes became dominant. Leaves larger amount of phosphorous, potassium and calcium stored. Besides the absolute element content, the ratio of the different elements was also determined. Majority of calculated ratios were removed from optimal values due to frost. Both absolute content of nutrients and their ratios pointed out that the frost damage significantly affected the uptake of nutrients and their storing processes.

• Long term investigations of flowers and leaves on mainly non-domestica plums

  73-79.

  D. Surányi

  Views:

  161

  The author dealt with plum species representing different eco-geographic areas by their genetic adaptation and their hybrids, as European (P. domestica, P. italica, P. cerasifera), Asian (P. salicina, P. simonii, P. ussuriensis), American (P. americana, P. besseyi, P. munsoniana, P. tomentosa). The rootstocks of the trees examined were seedlings of C. 679 myrobalan with the exception of Laroda and Santa Rosa II, which were grown on three different stocks: seedlings of C. 174 myrobalan, C. 449 bitter almond and C. 471 sweet almond. The size of peduncle, length of pistil, stamen number per flower, relative stamen number (SN/PL) have been suitable for description and distinction of varieties. Similarly shape of leaves, length of petiole, length and width of blade helped the identification.

  The ratio of the dimensions of leaves, length of petiole and of leaf blade, also contributed to the distinction of European, Asian and American plum species, notwithstanding their relations with ecological conditions as well as historical, technical properties, pomological features, etc. Computed indicators (relative stamen number and shape-index of leaves) also have been useful data.

  Significant correlations have been found between colour of nectaries and mean values of variety-groups. The potential values of non-European varieties for purposes of commercial production could be forecasted from the point of view of quality, ecological, pomological as well as market value. It is important, however, to know the effect of the rootstock and growing site as well as their interaction, on the one hand, whereas the resistance or tolerance of the varieties as limiting factors, at least to the sharka (Plum pox) virus, Xanthomonas pruni, on the other hand (cf. Surányi & Erdős, 2004a and 2004b).

• Investigation on the transmission of some Tobamoviruses by pollen and seed in pepper (Capsicum annuum L.)

  127-131.

  P. Salamon

  M. Kaszta

  Views:

  228

  Five pepper cultivars were mechanically inoculated with isolates of three Tobamovirus species, viz. the "Gelb" strain of tobacco mosaic virus (TMV-G), the XM-isolate of dulcamara yellow fleck virus (DYFV-XM) and the Nov/H isolate of pepper mild mottle virus (PMMV-Nov/H), respectively. Symptoms caused by the viruses were characterised. The viruses were sucessfully re-isolated from different organs (roots, leaves, fruit parts) of susceptible peppers to test plants. It was estabilished, that the pollen of diseased peppers carried infective virions at least on their surface. Washes of seeds were highly infective, but no infectivity was found after treatment of the seeds with 2% NaOH or 10% Na3PO4. No infectivity of inocula prepared from seed-coats of alkaline treated seeds was established. Infection of young seedlings grown from untreated seeds was demonstrated, while the seedlings came from alkaline treated seeds remained free of infective virus. The possible role of pollen and seed in the epidemiology of Tobamoviruses pathogenic to pepper as well as the importance of seed treatment is discussed.

• The effect of climatic anomalies on the nutrient supply of fruit plantations (Minireview)

  111-116.

  P. T. Nagy

  M. Sipos

  Z. Szabó

  M. Soltész

  J. Nyéki

  Views:

  221

  Climatic conditions play an important role in agricultural production. It has a profound influence on the growth, development and yields of a crop, incidence of pests and diseases, water needs and fertilizer requirements in terms of differences in nutrient mobilization due to water stresses. Nowadays, we have to know the dark side of the weather events because it is causing more and more problems and significant hazards to many horticultural regions in Hungary. The aim of this study is to explore the problems of nutrient uptake following climatic anomalies and response. These problems are: (i) water supply problems (water-stress); (ii) drought and frost as temperature­ strees. Reviewing the effects and nutrient disorders caused by climatic anomalies, the following statements can be taken:

  • Nutrient demand of trees can be supplied only under even worse conditions.
  • The most effective weapon against damage of climatic anomalies is preventative action.
  • When developing a fruit orchard, three factors should be taken into consideration: "Location, Location, Location".
  • Moreover, proper choice of cultivars, species and cultivation should provide further possibilities to avoid and moderate the effects of climatic anomalies.
  • Fruit growing technologies especially nutrition should be corrected and adjusted to the climatic events as modifier factors.
  • Urgent task of the near future is to correct and adjust the tested technologies of fruit growing according to these climatic events as modifier factors.

  Optimal nutrient supply of trees decreases the sensitivity for unexpected climatic events. To solve these problems supplementary, foliar fertilization is recommended, which adjusted to phonological phases of trees.

  Another solving is groundcover of soil means a potential opportunity to temper or even avoid climatic anomalies.

• The selection and cultivation of Tilia clones tolerating polluted urban environment

  82-86.

  E. Jámbor-Benczúr

  Z. Sinkó

  M. L. Reményi

  Z. Ifjú

  Views:

  207

  Two urban stress tolerant Tilia clones were selected by the Department of Floriculture and Dendrology. The mother trees of the Observed clones were found in an alley of linden trees, settled on a traffic island of a busy two-lane road.

  Tilia hybrid 'Saint Stephen' has a beautiful cone-shaped crown, the leaves are bright green and they keep their green colour for much longer time than the leaves on the other trees in the alley. In the nursery the Tilia hybrid 'Saint Stephen' was budded on T. cordata, T. platyphyllos and T. argentea and it had good compatibility with every rootstock. The average height of the one year old buddings was 200 cm and the buddings kept their good growing capacity in the following years as well. They had an outstanding growing capability comparing with the other Tilia cultivars.

  Tilia platyphyllos 'K3' clone has similar cone-shaped crown. The growing vigor and urban stress tolerance seems to be better than Tilia hybrid 'Saint Stephen'.

   

• The effect of the limitation of insect pollination period on the fruit set and yield of temperate-zone fruit tree species

  90-95.

  P. Benedek

  J. Nyéki

  M. Soltész

  Z. Erdős

  I. Skola

  T. Szabó

  I. Amtmann

  F. Bakcsa

  G. Kocsisné Molnár

  Z. Vadas

  Z. Szabó

  Views:

  141

  The duration of effective bee pollination period was limited by caging flowering branches for shorter or longer time in blooming fruit trees in a number of experiments during the past decades. In the case of self-sterile fruit species and cultivars (apples, pears, quinces, some plums, some sour cherries) even partial limitation of the effective duration of bee pollination period significantly reduced the fruit set and the yield. In the case of self-fertile apricots the effect of the total and also the influence of partial limitation of bee pollination period was the same as in the case of the mentioned self-sterile fruits. On the other hand, in the case of another self-fertile fruits (some plums, some sour cherries), the effect of partial limitation of bee pollination period was usually small, but complete (or incomplete but strong) limitation of be pollination usually resulted in a strong reduction of yield. This means that not only self-sterile but also self-fertile fruits clearly depend on insect (bee) pollination. This is because pollen dehiscence of anthers and the receptive period of stigmas do not overlap in time within the individual flowers. Stigmas in self-fertile trees, therefore, need pollen carried by bees from another flowers of the same tree (or compatible pollen from another trees). Accordingly, additional bee pollination (moving bee colonies to the orchards in flower) is needed to all kinds of temperate-zone fruit tree species when bee visitation of plantations is not abundant enough for some reasons.

• Apple powdery mildew caused by Podosphaera leucotricha: some aspects of disease management

  29-33.

  I. J. Holb

  Views:

  529

  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. This review focuses on the control of apple powdery mildew. The first part of the study provides details of novel aspects of non-chemical control approaches, including agronomic measures, mechanical and biological control options as well as essential features of apple cultivar resistance. After this, developments in chemical control options are described sperately for integrated and organic apple orchards.

• Blooming time of some apricot varieties of different origin in Hungary

  16-20.

  L. Szalay

  Z. Szabó

  Views:

  325

  There are a number of self-incompatible and partially self-compatible apricot varieties which need cross pollination for suitable yield. We have to know their blooming time to select the appropriate pollen donor cultivars. The blooming period of 20 apricot varieties was observed in four subsequent years. Blooming time was affected by temperature conditions very much. Varieties studied were assigned to three groups according to their blooming time. The rate of overlapping of important variety combinations was observed. Sufficient overlapping of blooming period for safe pollination is usually ensured within the same group of varieties or between varieties of the neighbouring blooming time groups.

   

• Evaluation of potential of fruit weight and fruit width and their interrelationships in the set of apricot genotypes

  47-53.

  Z. Vachon

  Views:

  98

  Within the period of 1994-1999, variability of fruit weight and width was evaluated in altogether 24 apricot genotypes. It is concluded that the genotype and climatic conditions of individual years are the factors causing variability in these two parameters of apricot fruits. Variability of fruit weight was significantly higher (approximately 3-times) than that of fruit width. When evaluated on the base of their width, 75.0% and 95.8% of apricots were classified into the groups of extra and first quality, respectively. As genotypes with the maximum fruit width (i. e. above 50 mm) the following cultivars were classified: 'Velkopavlovicka LE-6/2', 'NJA-1', 'M 45', 'M-25' and lednicka (M-90-A)'. The value of fruit width (in mm) corresponded with its weight (in g) only within the range of 40 — 45 mm. With the increasing and/or decreasing size of apricot fruit the changes in fruit weight were more pronounced than in those in fruit width. Within the set of genotypes under study, this relationship may be expressed by the equation y = 0.1234 — 7.6605 + 152.76; the corresponding values of correlation coefficient and coefficient of curve determination are r = 0.95-H- and R2 = 0.959.