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• Examinations of potential environmental friendly materials against tomato and pepper patogens

  49-54.

  A. Tóbiás

  J. Lehoczki-Tornai

  Z. Szalai

  L. Csambalik

  A. Ferenczy

  Views:

  365

  In organic farming systems the focus is on prevention with regards to plant protection. To follow the rules of Good Agricultural Practice one is able to avoid serious yield losses; if it is not possible the use of allowed materials are permitted. Organic farmers have less material to protect their plants so it is necessary to find effective potential materials. Bacterial and fungal diseases of tomato and pepper can cause serious losses in yield. Different materials were tested against some plant pathogen bacterial (Clavibacter michiganensis subsp. michiganensis, Pseudomonas syringae pv. tomato, Xanthomonas campestris pv. vesicatoria and fungal (Phytoptora infestans, Rhizoctonia solani, Sclerotinia sclerotium) strains in order to find potential materials in the field of organic seed treatment. In vitro trials have shown that vinegar, cider vinegar, red wine vinegar, white wine vinegar, cinnamon and thyme oil have inhibiting effect against the causative agent of bacteria and fungi. Germination test has shown that examined vinegar types do not decrease germination ability if the concentration is low, but in higher (more than 5%) concentration it ruins the germination ability. Even in 0,5% concentration of red — and white vine vinegar have good effect on germination capacity.

• Pedological and agrochemical investigations on media using in vegetable forcing

  119-122.

  Sz. Jakusné Sári

  Views:

  196

  In spite of the several good properties of peat, recently, some experiments were carried out with the aim of finding natural materials which can substitute for peat. According to the results, several inorganic and organic materials were proved to be suitable for this purpose. This study examines the effect of different organic materials (example: pine bark, composts, peats) on the growth and yield of green pepper (Capsicum annuum L., variety Danubia). We found that the most developed plants were grown in peat-mixtures and pine bark. The average fruit weight was the highest at those plants which were planted also in these media. The plants which were grown in composts fell short of our expectations in development and in yield, too.

• Effects of initial spacing on the stand structure and yield of young black locust (Robinia pseudoacacia L.) stands

  37-39.

  K. Rédei

  Views:

  330

  The choice of the right initial spacing of stands is one of the most decisive operations of a successful afforestation. It is even more important in the case of fast growing tree species grown in plantations; it is expressed in their early phase of development and in wood quality. The results of a 5-year long experiment with four treatments will be presented in this paper. They proved the priority of an initial spacing of 1.61.0 m in the majority of quality This treatment has been proved optimal exploitation of growing space by the young trees.

• Economic aspects of aged apple plantations in Hungary

  13-16.

  F. Apáti

  J. Felföldi

  Views:

  327

  Being competitive is a goal all over in the EU. Competition is free and getting closer among the competitors of the apple industry. In Hungary, one of the most important issues of apple industry has been what are the prospects for aged plantations, which account for 50% of crop land. Based on our results, 80% of those apple plantations on the down-grade yielding apple, the ones only for processing, do not meet the criteria of competitive production. For those plantations in better shape that yield 30-40 t/ha, of which at least 20-30% are for fresh production, it can he profitable. Because of the future trend in technology and economy, however, even the latter ones can not be considered being competitive in the long run.

• Association of European plum varieties in the orchards

  21-24.

  Z. Szabó

  J. Nyéki

  A. Andrásfalvy

  M. Soltész

  Views:

  1191

  The flowering phenology, blooming time and inter-fertility relations of 63 European plum varieties has been studied at growing sites with different ecological conditions during a 10 year long period. The purpose was to develop a system of variety combinations which approaches an optimum in fertility as long as inter-fertility relations will cease to be a limiting factor of yield. According to their blooming time, varieties are assigned to 5 groups: very early, early, medium, late and very late. As for their fertility relations, four groups are formed: self-sterile (0%), partially self-fertile (0.1 to 10 %), self-fertile (10.1 to 20 %) and highly self-fertile (more than 20 % fruit set with self pollination). The four categories of fruit set at free pollination are also relevant to the grower: low (less than 10 %), medium (10 to 20 %), high (20 to 40 %) and very high (more than 40 % fruit set).

  By artificial cross pollination, one combination Cacanska najbolja x Stanley proved to be mutually inter-incompatible. Blocks planted to a single self-sterile variety flanking a pollinizer variety proved the spacial distribution of the pollen. The reduction in fruit set was already apparent in the second row away from the pollinizer trees. In a large plantation, without bee hives, relatively low yield was stated on self-sterile trees even close to the pollinizer.

  In the case of self-sterile and partially self-fertile varieties, a combination of three varieties is recommended. The blooming period of the pollinizer variety should overlap the period of the self-sterile variety at least by 70 %, and the distance should not exceed 15 to 20 meters. Association of self-fertile varieties may also enhance the productivity of the trees. In that case an overlap of 50 % in blooming time and a maximum distance between the varieties of 30 to 40 meters will be sufficient.

   

• Influence of irrigation and row spacing on the growth, seed yield and active substance of milk thistle (Silybum marianum)

  78-81.

  G. Karimzedah

  R. Omidbaigi

  Bakhshai D.

  Views:

  287

  Milk thistle (Silybum marianum (L.) Gaertn) has been used in medicine since ancient times, but it has been cultivated as a medicinal plant only in recent decades. The ripe fruit of milk thistle contains flavonoids, which are used to prepare anti-hepatotoxic drugs. The main purpose of this study was to substantiate the effects of irrigation and row spacing on growth, seed yield and the content of active substances (silybin and silymarin) in milk thistle. The results showed that the suitable amount of irrigation was 20 mm and the appropriate row spacing was 25 cm.

   

• The uses of wolfberry (Lycium barbarum L.) as a fruit in an international breadth of view

  7-13.

  R. Sóspataki

  M. Józsa

  G. Simon

  Views:

  505

  Lycium barbarum is known exclusively as an ornamental plant in Hungary, and is planted so, as popular belief deem it a toxic plant. The plant’s fruit receives great respect in countries abroad, thus, due to its favourable content values the Lycium has achieved the title of ‘biological gold mine’. The last couple of years has seen the import of Lycium shrubs and its corresponding products, dried goods or in the form of various processed products which have been marketed and sold at extreme prices (under name of Goji, Wolfberry, Lifeberry). Our goal was to examine the similarities of the content values of wolfberry found in Hungary and those cultivated abroad. Along with Miklós Józsa the domestic Lycium population was surveyed based on foreign examples, between the years 2009 and 2011. Those defined sweet and largefruited were selected for further investigations to be set into a clone repository. This clone repository– which contains 67 different clones from a number of regions of Hungary – was established in the nursery of Dr. Miklós Józsa, located in the city of Szombathely. The phenological and morphological characteristics and the fruit ripening and quality indicators of plants in the clone repository were investigated. Six ‘best’ clones – selected based on flavour, disease-resistance and vegetative characteristics (plant size, fruit set, yield and fruit size) were analysed based on their content values. The control plant was a cultivar imported by a delivery service, found also in growing. In addition to the results of the selection, the results of the content values of the six selected ‘best’ clones (total soluble sugar content, glucose-fructose ratio, carotene content, FRAP value) is documented in this paper. Further, based on the resulting information the possibilities of the fruit’s utilization are suggested. Significant differences were measured in the vegetative characteristics of the clones (plant size, fruit set, yield and fruit size) and of those of
  its inner content values. The resulting properties are considerable in regards of the plant’s introduction into cultivation and also utilization. Based on growing characteristics, more favourable clones were selected than the foreign varieties already in growing. Those clones selected by us have had similar or better content values than foreign breeds. The investigation of these content values is still in progress.

• Fruit formation dynamics in parthenocarpic cucumber (Cucumis sativus L.) in spring forcing

  111-114.

  L. Helyes

  Z. Pék

  Views:

  293

  20% of the cucumber crop of the world belongs to the parthenocarp type. Parthenocarp cucumber forcing has a great importance in Hungary, too. In our country the whole area of parthenocarp cucumber forcing was approximately 500 ha of the last years (2000-2002) and 75-85000 tons of yield has been harvested (MGYSZT, 2003). It means 15 — 17 kg/m² as an average yield. In European forcing systems, parthenocarp cucumber is usually planted in January or February and it is harvested in spring or early summer. In Hungary cucumber forcing is the most profitable in two separate periods: spring and autumn, the reason for it is the changes of the average prices of fresh market cucumber, but spring forcing is still the most profitable. Forced cucumber cultivars are mostly parthenocarp; non-parthenocarp cultivars are grown in summer preferably. Cucumber cultivars, forced in our country, are hybrids, and 90% of them are offered by foreign seed companies (KristOfne, 1998.). The productivity of these hybrids is high and the productive period is quite short. All the mentioned details give the reason why it is important to know everything about the productivity, the dynamics of growth, and the possibilities of timing of parthenocarp cultivars, and it is also important to learn how to control all these parameters. Our spring cucumber-forcing experiment aimed to characterize of those parameters mentioned.

• Effect of Foliar Nutrition on Post-Harvest of Onion Seed under Sandy Soil and Saline Irrigation Water Conditions

  85-92

  S. A. Shehata

  M. Y. Hashem

  G. I. Mahmoud

  K. F. Abd El-Gawad

  H. R. El-Ramady

  T. A. Alshaal

  É. Domokos-Szabolcsy

  N. Elhawat

  J. Prokisch

  M. Fári

  Views:

  420

  Foliar application has been determined to be an effective nutrients delivery strategy in vegetable and fruits. The enhancement of vegetable and fruit yields affected by foliar nutrients application has been recognized in previously conducted studies with perennial tree crops. The efficiency of foliar nutrition is dependent on soil, climate, fertilizer and the amount of nitrogen used. There is no sufficient information concerning cooperation of foliar nutrition with all nutrients form as well as the rates of these nutrients fertilization in vegetable
  and fruit crops. Two successive winter seasons of 2008/2009 and 2009/2010 were conducted under sandy soil conditions to study the effect of spraying with 12 commercial compounds on inflorescences diameter, flower stalk length, number of seed stem /plant, weight of 1000 seed, germination percentage, seed yield, moisture content, catalase , peroxidase activity and malondialdehyde content of onion seeds. The plants
  sprayed with union Zn, union Mn, union feer, shams k, elga 600, boron, and amino x had the highest vegetative growth parameter, germination percent and enzyme activity. The plants sprayed with union Zn, union feer, shams K, magnesium, caboron, hummer and amino X had the highest seed yield ha-1. The seeds were stored for one year to study the effect of different commercial compounds and storage temperatures on germination, moisture content and change in antioxidant enzymes activities of onion seeds during the storage period. Storage at cold temperature showed higher germination percent, moisture content and lower malondialdehyde content than storage at room temperature. The treatment with union Zn, union feer, union Mn, boron, elga 600, caboron, amica, hummer and amino x had the highest germination percent.

• Effect of water supply on nutrient transport in grapevine varieties

  64-68.

  E. Miklós

  E. Hajdu

  É. Ésik

  Gy. Gábor

  Gy. Váradi

  Views:

  264

  The effect of water supply on availability of macro nutrient elements (N, P, K) by the plants in the soil and their transport in the plants were examined. In a field experiment two grapevine varieties characterized by higher (White Riesling B 7) and lower (Kövidinka K 8) water requirement were compared on the basis of N, P, K concentrations of leaf blades, petioles and berries. A different water supply of the vineyard was achived by striped coverage of the soil with plastic foil to exclude rainfalls from the beginning of May to ripening. Humidity of the soil decreased as the vegetative phase advanced. Soil cover resulted in 25-30% decrease of the water content in the soil at flowering but this difference gradually disappeared till veraison (i.e. the start of intense growth of the berries). The water consumption in the White Riesling B 7 plantation was more intensive. Mobility and availability of N, P, K in the soil was restricted by water exclusion (i.e. plastic soil cover) at flowering. Nitrogen was slightly affected, whereas P and K were in a higher extent. Comparing the transport of nutrient elements in the two varieties, leaf blades of Kövidinka K 8 contained less N and more P and K than White Riesling B 7 at flowering and more N and P and less K at ripening. Water deficiency inhibited K accumulation in the berries of White Riesling B 7, while this effect did not appear in Kövidinka K 8.Water exclusion decreased the yield of White Riesling B 7 already at lower bud loading, the yield of Kövidinka K 8 was affected only at higher bud loading. The higher yields of the treatments in Kövidinka K 8 plantation support the superior performance of this variety under the hot and dry climate of the Hungarian Great Plain.

• Irrigation of pear (A review)

  65-73.

  E. Nemeskéri

  Views:

  406

  The plantation of intensive growing orchards and steady increase in yield is essential to return the growing cost by sale. Seasonal crop fluctuation of pear is increased by the frequently occurrence of drought and climatic changes. This study reviews genetic and growing factors determined the alternancy of pear and present the new knowledge concerning on water saving irrigation techniques. Use of dwarfing rootstocks, root pruning, branches pruning and new water saving irrigation make the changes in vegetative and generative growth that successfully improve the alternancy of pear growing. According to publications BA 29 of clonal quince rootstocks exhibited the best protection mechanism against to drought. Regulated deficit irrigation (RDI) applied during rapid shoot growth and slowly fruit growth result a decrease in shoot growth and 60% of water saving in pear orchard while there was no influence on harvested yield. Partial rootzone drying (PRD) microjet irrigation applied in pear orchard result 23-52% of decrease in water use, however concerning explorations are contradictory. Further investigations need to improve the efficiency of new irrigation technology adapted pear varieties based on monitoring of soil water status and measurement of stem water potential as stress indicators of plants.

• Biological performance of grape varieties in Eastern Hungary

  31-35.

  N. Rakonczás

  Views:

  378

  Eurasian and interspecific grape varieties and candidates were inspected for biological productivity in the variety collection of the University of Debrecen at the Horticultural Experimental Station in Pallag. In this paper, data are reported on yields (kg/stock), cane production (kg/ stock) and use-up index of wood yield of each cultivar in the experimental years 2011-2012. From the range of Eurasian (Vitis vinifera L.) white wine-grape qualified cultivars and candidates ’Ezerfürtû’, ’Generosa’, ’Jubileum 75’, ’Müller Thurgau’, ’Zöld veltelíni’,’B-11’, ’CSFT-92’, ’Pintes’, from the range of Eurasian (Vitis vinifera L.) red wine-grape qualified cultivars and candidates ’Kármin’, ’Pinot noir’, ’Alicante Bouschet’ and ’Rubintos’ were highlighted. Promising data of interspecific ’Aletta’, ’Csillám’, ’Kunleány’, ’Orpheus’, ’Refrén’, ’Taurus’, ’Viktória gyöngye’, ’Alföld 100’, ’Reform’, ’RF38/32’, ’Toldi’ white, and ’Dunagyöngye’ ’Pannon frankos’ red wine-grape cultivars and candidates were emphasized. Published data refer only to the biological performance of the cultivars. The thorough evaluation of varieties needs respect to data on resistance to fungal disease and climatic extremities, and other characteristics concerning production technology and oenological parameters.

• Propagation material borne fungus pathogens causing early stock decay in vineyards

  51-57.

  T. Dula

  Views:

  330

  A decline, a slow or sudden decay of vine trunks can occur in any phase of trunk life. In senescent or old plantages the increase in trunk decay is quite common but it is unacceptable in young plantage in their best production years.All over the world as well as in Hungary, a drastic decay of young trunks in nurseries and new plantages have caused panic in the past decades. From among the numerous fungal pathogens which are responsible for considerable financial and yield losses and threaten stock vigour Petri disease, esca and Black foot are the most important. In young decaying plants the fungal species Phaeomoniella chlamydospora, Phaeoacremonium spp. and Cylindrocarpon spp. were the most frequent while other fungi causing different trunk diseases, cancer or decay, like Eutypa lata, Botryosphaeria spp. and Fomitiporia mediterranea were also found. The most important infection source is the infected propagation material. Infection is systematic, the disease process is latent, diseased plants cannot be cured, thus, prevention is the only answer to the challenge.

• Investigation of the cultivation value of old grapevine cultivars in Tokaj in 2004-2006

  23-27.

  Zs. Varga

  F. Bényei

  P. Jr. Bodor

  I. Fazekas

  Views:

  317

  Most of the cultivars grown before the disaster of phylloxera in Tokaj can be found only in grapevine collections. The aim of our study was to determinate the cultivation values of six old grapevine cultivars of the wine-region, namely 'Balafánt', 'Budai gohér', 'Purcsin', 'Török gohér, 'Piros (red) furmint' and 'Változó (altering) furmint'. Based on the results of the investigations from 2004 to 2006 it can be concluded that among from the examined cultivars of Tokaj `Budai gohér', Turcsin' and 'Változó furmint' match the best with the technological and consumer requirements of recent days. However the yield of 'Budai gohér' in certain vintages is not acceptable and red wine cultivars are not permitted at this time in the wine-region, but in qualitative responses these presented steadily good data. On the other hand the lowest sugar content was measured and development of noble rot was not registered at all in case of Piros furmint' and `Balafánt'. Their spread in Tokaj is not probable.

• Self-fertility studies of some sweet cherry (Prunus avium L.) cultivars and selections

  21-26.

  Zs. Békefi

  Views:

  273

  Fruit set of two sweet cherry cultivars (Alex' and 'Stella' ) and four Hungarian selections have been studied over two years following open pollination, unassisted self-pollination (autogamy) and artificial self-pollination (geitonogamy). Among accessions 'IV-6/240' proved to be self-sterile, while the other five revealed to be self-fertile. Significant differences have been found in fruit set among years and among pollination treatments but not among self-fertile accessions. Fruit set following unassisted self-pollination was significantly lower than of other pollination treatments. Thus pollen transfer is essential for profitable yield in sweet cherry growing.

  There was no significant relationship in the fruit set of open- and self-pollination.

• Some flower characters, variety features and environmental effects affecting bee pollination of pear (Pyrus communis L.): a review of the results of latest research

  59-66.

  P. Benedek

  Views:

  342

  Intensive research has been implemented on different aspects of the bee pollination of pear in Hungary in the past decade, extending to the following topics: the effect of the opening sequence of the flowers within the inflorescence of pear cultivars on the effectiveness of bee pollination; the nectar production of flowers of pear cultivars; intensity of honeybee visitation and their foraging behaviour at the flowers of pear cultivars; flower constancy of honeybees to pear plantations; competition by weeds in bloom for bee pollination in flowering pear orchards; and some aspects to the bee pollination strategies of pear plantations (the effect of the limitation of bee pollination period on the set and the yield, possible compensation of frost damage of flowers by bee pollination in pear orchards, the optimal size of single cultivar block in pear plantations). The results of these studies are reviewed in this paper and some important aspects that need further studies are outlined.

   

• Turkish hazel (Corylus colurna L.) in Hungary: A case study on its forestry potential

  48-51.

  T. Ábri

  L. Magyar

  K. Rédei

  Views:

  290

  This study investigates the structure and growth of a 73-year-old Turkish hazel (Corylus colurna L.) plantation in Hungary. The stand had a tree density of 290 per ha, mean height of 18.2 m, quadratic mean diameter of 34.2 cm, and a basal area of 26.7 m² ha⁻¹. The slenderness ratio of 0.55 indicates moderate stability. Diameter distribution was normal (22–53 cm). Crown structure parameters showed moderate correlations with diameter (R² = 0.59 for crown diameter; R² = 0.53 for crown projection area), emphasizing the role of crown traits in yield modelling. An optimal planting density of 434 trees ha⁻¹ was estimated based on the average crown projection area (23 m²). Turkish hazel, with its drought resilience and valuable wood, is a promising species for afforestation in semi-arid climates. However, further research is needed on its management and genetic improvement to support wider application. This study can be considered gap-filling both in a Hungarian and, to some extent, an international context.

• Some microbial treatments against the tomato leaf miner; Tuta absoluta (Merick) under natural field conditions

  81-84.

  Mohammed Amira S.

  El-Khatteeb Nagwa M. M.

  A. Ezzat

  Views:

  346

  In an attempt to find more effective methods and safety to control the tomato leaf miner, Tuta absoluta, this research was conducted to study the efficacy of the four bio-treatments ; two bacterial isolates (Bacillus subtilis. and Pseudomonas Fluorescence), one fungal isolate Trichoderma viride) and Spinosad as a microbial insecticide compared with the most common insecticides used against the dipterous and lepidopterous leaf miners in Egypt; Profenofos and Aphox. In the two successive seasons; 2011 and 2012, the fungal isolate Trichoderma viride achieved the lowest infestation(numbers of infested leaflets, mines, infestation percentages) which were 167, 195, and 21.9% resp.in season 2011 and 198, 222 and 26.2% resp. in season 2012. While the highest infestation was occurred in case of using the insecticides, Aphox (423, 559 and 55.9% resp.& 384, 839 and 72.2%. and Prohpenofos (436, 562 and 57.7% &391, 534 and 51.7% resp.).during 2011 and 2012 respectively. The other treatments occupied the intermediate levels. On the other hand, the yield of tomato fruits was increased by 75% over the check in case of plants treated with Trichoderma viride isolate, but the pesticide treatment given weak or no impact in increasing tomato crop. In season 2012, the infested tomato fruits percentages with T. absoluta larvae and Rhizoctonia soil rot disease(that Frequently observed incidentally) were recorded the minimum levels obtained by spraying Trichoderma viride isolate(21.38 and 10.32% resp.). In contrast, the maximum levels were recorded in Prophenofos (44.87 and22.78% resp.) and Aphox treatments(47.22 and 27.78% resp.).

• Heat waves in Hungarian plant production

  113-118.

  A. Révész

  K. Szentteleki

  L. Horváth

  Views:

  306

  A momentous inference of heat waves is the economic effect. The main demage after the human problems will caused by theese extreme events in agriculture. For example a long hot peiod without any percipitation can exterminate not only the annual yield, but also it can demage or in extreme situation it can destroy the whole orchard. Especially endangered most of the fruits, because an extreme summer with high temperature which usually goes hand in hand with an arid period can modify growth of the plant. Our investigations show that according to the most widely accepted climate change scenarios heat waves are expected to be essentially longer and hotter than in the past. It might happen that events we now define as heat waves last through entire summer. Although it will not be general, the length and intensity of present heat waves could also multiply. Based on data provided by some global circulation models, we might be face an event that exceeds the hottest heat waves of the 20th century by as much as 12 °C. This study also offers a survey of the methodology of heat wave definition. Besides traditional calculations, we present two unconventional methods by introducing minimum and maximum temperature heat waves. We show in what points this approach is different from those usually adopted and what extra information it may offer.As an extension of the usual studies, with considering the length of events, we analyse the development of two variants – temperature and duration – and, as a result, classify the extreme heat events according to both length and intensity.

• Calculation of climatic probability of winter and spring frost damages in the main peach and apricot growing districts of Hungary

  99-106.

  L. Lakatos

  Z. Szabó

  L. Szalay

  M. Soltész

  J. Nyéki

  Views:

  911

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

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

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

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

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

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

• Bud-, flower- and fruit-density in stone fruits

  59-69.

  Z. Szabó

  J. Nyéki

  Views:

  985

  In 164 varieties of five stone fruit species, counts of flower buds, flowers and fruits set have been performed, regularly, between 1982 and 2002. The critical number and sample size has been determined for the purpose to estimate the yielding potential of peach plantations. For a rapid test, 10 shoots per variety are recommended. In sour cherry and peach varieties, the number and ratio of leaf and flower buds has been assessed on bearing shoots of different length.

  The typical flower bud density of 129 peach varieties varies, as a rule, between 0.13 and 1.10 bud/cm. Three groups of flower-bud-densities could be distinguished: low (0-0.40 bud/cm), intermediate (0.41-0.60 bud/cm), high (more than 0.60 bud/cm). About 62% of varieties belong to the intermediate group. Negative correlation has been found between flower density and relative fruit set, whereas positive correlation between flower density and fruit yield.

  The results are utilised in the description and choice of varieties, moreover, in choosing of optimal pruning policies. Varieties of high flower bud densities are recommended to be preferred for growing sites with frequent late frosts. Abundantly yielding varieties of low vegetative vigour are to be pruned more severely than those characterised by low yields, vigorous growth and low flower density. Sour cherry varieties, which are inclined to grow "whips" ought to be stimulated to grow longer shoots (40-50 cm per year), than varieties woid of that tendency (30-40 cm).

• 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:

  707

  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.

• Effect of hail protecting nets on the quality of apples

  77-80.

  I. Gonda

  B. Vaszily

  A. Bartha

  M. Soltész

  Z. Szabó

  J. Nyéki

  Views:

  1039

  Today, successful fruit growing depends largely on the security of production. Among the technological elements of a secure growing system, the use of hail protection nets serves special attention. Components of security are the regularity, conspicuous large yields with excellent quality, which determine the prices and profitability as well (Szabó et al., 2010). In the European Union, most of the apple growing countries produce higher yields by 10-20% than Hungary. The conditions of better yields are partly due to a more favourable ecological milieu, partly to more developed technologies and serious discipline of the operations. Our own competitiveness could be developed first of all in those moments. As a consequence of global climatic changes, excesses of weather, i.e. hail-storms became more frequent. Different methods of protection against hail are developed abroad but also in Hungary. The examination of effects of the hail protection nets compared with the check without nets has been the purpose of our experiments. The growing system was the intensive one with high planting densities. Fruits of the two subsequent years have been compared as grown with and without hail protective nets. It turned out that in one season when shoot growth was stimulated, the shadowing effect of the net increased in addition the growth and at the same time braked the differentiation of flower buds, which exerted negative effects on yield of the next year. Let alone this phenomenon, the quality of fruits was not influenced by the hail protection net.

• An investigation of genotype-environment interaction and stability for pea (Pisum sativum L) seed yield

  53-55.

  L. Csizmadia

  F. Kormos

  Views:

  212

  Eighteen pea breeding lines and three check cultivars were tested in two years with and without irrigation. The linear regression can explain only a small part of GEI so the use of regression technique was not possible for interpreting the data. In this case the ecovalence, stability variance and superiority measure stability parameters cannot describe properly the genotype's response. With the AMMI method it is possible to group properly the genotypes according to their response.

• 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:

  808

  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.