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• Six promising selections from the Hungarian apple breeding program for multiple resistance

  23-28.

  M. Tóth

  Views:

  369

  An apple breeding program has been carried out at the Department of Fruit Science for more than a decade. Several apple selections have been released from the progenies of crosses in 1992 and 1993. Six candidates were submitted for national recognition out of the hybrids examined for more than a decade. The six selections are resistant against all the three most important apple diseases (apple scab, powdery mildew and fire blight). Scab resistance is controlled by the Vf gene originating from the species Malus floribunda 821 and transmitted by cultivar Prima. Heterozygote Vfvf genotype of the six cultivar candidates was proved by molecular genetic examinations of Dept. Genetics and Plant Breeding. Characteristics of these selections from 'Prima' progenies are shown on the base of our own observations.

• Epiphytic microbiota of apple in integrated and organic growing

  85-89.

  Sz. Pintér

  J. Benczer

  Z. Szabó

  J. Nyéki

  Views:

  982

  The surface microbial contamination is of great interest in case of fruits, since they are they potential sources of spoilage or foodborne diseases. The aim of this work was to compare the epiphytic microbiota of food safety concern of different apple cultivars as a function of cultivation methods (organic versus integrated), production year and place. Investigating 47 samples it was found that the average microbial contamination of the apple surfaces was within a certain range,, practically independent of cultivar, growing area and year. The frequency distribution of the surface bacterial, mould and yeast counts did not show significant differences between growing technologies or varieties. The principal component analysis the samples ranked the apple samples into seven groups on the basis of their microbial contamination level, and the discriminant analysis proved the goodness of grouping. The grouping was independent from cultivars and growing methods. No foodborne pathogen Salmonella spp. and Listeria spp. were found on the surfaces of apples.

• Growing experiments with a medicinal mushroom Agaricus blazei (MURRILL)

  45-48.

  A. Geösel

  J. Győrfi

  Views:

  467

  The demand of natural and medicinal products has been increased for the past years. These products are often made from herbal and medicinal plants, and recently the mushroom products are much called. Nearby some well known species (like Lentinula edodes or Ganoderma lucidum) some not respected biomedicines are available in Hungary. Agaricus blazei (Murrill) is a Basidiomycota fungus, with almond-like taste and nice texture. This medicinal mushroom proved to be useful in cancer therapy and against some bacterial and viral diseases. In our experiment we tested 8 Agaricus blazei strains on fermented mushroom compost. The yields, average mushroom size, productivity and biological efficiency of the species were measured. Our data demonstrate that it is possible to get fruit bodies less than 2 months, and strain "837", "2603" and "MaHe" are suggested for further experiments. These strains gave the highest yield and efficiency in the cultivation.

• Cracking susceptibility of sour cherry (Prunus cerasus L.) in Hungary and relation to calcium application

  109-118.

  G. Simon

  M. Tóth

  J. Papp

  Views:

  820

  The rain induced fruit cracking is a big, serious problem especially for sour cherry growers but in some year sour cherry growers had also problem with fruit cracking caused by too much rainfall in the harvesting season. The cracked sour cherry fruits can be easily infected by different diseases like Monillinia sp. Cracked and infected fruits can not be transported for long distance and using for preservation because they lost their market value by the pour fruit quality. There are two possibilities to protect fruits against the rain induced fruit cracking. The most effective protection technique is the plastic rain cover over the tree rows. The installation of these equipments is too expensive for the growers. That is the reason why researchers tried to find other less expensive and sufficiently effective ways like sprayings different mineral salts, hormone and other type chemicals against the rain induced fruit cracking. Several calcium formulas calcium chloride (CaC1₂), calcium hydroxide (Ca (OH),) and calcium nitrate (Ca(NO₃)₂) can be sprayed in appropriate solution concentration.

  The aim of our trial is to determinate the fruit cracking susceptibility of wide grown Hungarian sour cherry varieties and find the most effective calcium formula and its concentration for spraying in orchards to prevent the fruit cracking. In the first trial year (2006) cracking index of tested sour cherry varieties were determined under field and laboratory conditions. Under field conditions were not found differences between cracking tendency of tested cultivars. After results of immersing fruits in distillated water for 24 hours tested sour cherry varieties were divided to three groups by the susceptibility to rain induced fruit cracking: very susceptible (`Maliga emléke', 'Piramis', 'Érdi jubileum', 'Erdi nagygyümölcsű’ and 'Meteor korai'); susceptible ‘Érdi bőtermő, Tandy 279' and Cigány 59.; moderately susceptible/tolerant ("T" and "R" clones). In the second trial year (2007) calcium chloride (CaCl₂) and calcium nitrate (Ca(NO₃)₂) were sprayed in 0,35m/m%; 0,5m/m% and 1,0m/m% solution concentration. One more commercial product "Damisol-Kalcium" was also applied in the advised 1,0m/m% concentration. Like in the trial year before (2006) under field conditions we did not kept differences between the cracking susceptibility of varieties and calcium treatments. As the result of laboratory testing (immersing calcium treated fruits in distillated water) we kept that calcium chloride (CaCl₂) seems the most effective against the fruit cracking in 0,5m/in% solution concentration. The other calcium formulas also decreased the cracking ratio but in less scale.

• Review of nutritional value and putative health-effects of quince (Cydonia oblonga Mill.) fruit

  29-32.

  A. Hegedűs

  N. Papp

  É. Stefanovits-Bányai

  Views:

  1168

  Quince (Cydonia oblonga Mill.) has been long regarded to be a health-promoting fruit. Although it is mainly consumed in processed form, its relatively heat-stable polyphenolics were confirmed to be responsible for most of the beneficial effects. This review aims to show basic nutritional information on quince fruit such as carbohydrate, fibre, pectin and mineral element contents. In addition, vitamin and polyphenolic contents and composition as well as the physiological effects of quince consumption were also surveyed. Information on presumable protective effects against several diseases including infl ammation, atopic dermatitis, ulcers and cancer is summarized. Potential antibacterial effects of quince polyphenolics were also considered. Polyphenolics are supposed to be responsible for the major part of benefi cial health-effects, and phenolic compounds predominantly accumulate in peel. There exists a considerable extent of genetic variation in phytochemical composition among cultivars, which might be exploited in designing future breeding programs for quince improvement and opening new ways for health-related uses.

• Evaluation of fruit quality of old apple cultivars originating from the foot of the Carpathian Mountains, for utilization in breeding and in organic farming

  15-24.

  M. Tóth

  E. Balikó

  Zs. Szani

  Views:

  526

  In the frame of the apple breeding program at the Department of Fruit Science old cultivars found in the Carpathian basin were involved in examination as well. Beside testing susceptibility to fire blight (Erwinia amylovora of old genotypes (historical, local and regional cultivars) originating from scattered orchards of Visk (foot of the Carpathian Mountains), fruit quality was also evaluated and other open-field observations were made.

  According to the results of inner content examinations, 'Szemes alma' and 'Sikulai alma', chosen as gene sources for breeding to resistance against fire blight, had inner content values worthy to mention in some aspects, and competing with those of the control cultivar 'Jonathan'. The quality of 'Pónyik alma', also recommended as a gene source is confirmed by the data of earlier literature. Further three cultivars ('Batul', 'Vilmos renet', 'Zöld sóvári') also proved to be good based on resistance against Erwinia amylovora, the first two cultivars are suitable from the point of view of fruit quality, too.

  In our field observations, susceptibility to apple scab and powdery mildew was evaluated. Among cultivars selected from the foot of the Carpathian Mountains on the base of resistance against Erwinia amylovora, the production value of 'Szemes alma' is worsened by its high susceptibility to apple scab. Further selected cultivars ('Sikulai', 'Pónyik alma', 'Batul', 'Vilmos renet') are not too susceptible to fungal diseases and their fruit quality is also suitable, therefore they can be recommended for direct planting in ecological farming or in restoring scattered orchards.

• Nutritional aspects of producing fruits organically

  69-74.

  P. T. Nagy

  J. Nyéki

  Z. Szabó

  Views:

  1132

  Recent interest to avoid use of agrochemicals in fruit growing to safeguard environmental and human health has stimulated interest in organic fruit production (OFP) all over the world. Organic production requires a holistic approach to agricultural ecosystem management. Because of the perennial nature of orchards, this is not a great departure from conventional orchard management, except that corrective techniques are limited primarily to naturally derived materials. Organic mineral nutrition management hinges on two principles: 1) practices that lead to the build up and maintenance of soil that is biologically active and high in organic matter; 2) supplementing the mineral nutrients provided by the soil with fertilizers from approved sources. Organic orchards should be sited on land with superior soils and preplant soil preparation to increase organic matter and correct any sub-optimal soil characteristics. For successful organic fruit growing the following statement should be considered:Weed management is critical to reduce competition for nutrients and water. Soil and leaf analysis provide the basis for correcting mineral nutrient deficiencies or imbalances in organic production. It may be necessary to use a number of strategies to supply mineral nutrients over the life of the orchard. The slower, natural methods applied require a management approach that is simultaneously patient and dynamic.

• Agrobacterium transformation of Rhodiola sp.: current status and limitations

  37-42.

  A. Javid

  Zs. György

  Views:

  414

  The study of secondary metabolites has led to the discovery of new drugs for treating human diseases. However, consistent plant supply can be challenging, leading to the use of plant tissue culture techniques such as hairy root culture. Hairy roots have stable genetics, lateral branching, and can produce secondary metabolites, including alkaloids, flavonoids, and terpenoids. Research on hairy roots as a subject began in the late 19^th century, and for the last four decades, hairy roots have been utilized for producing secondary metabolites and recombinant proteins. This article focuses on Rhodiola species - genus of perennial plants that belongs to the family Crassulaceae - and its potential as a source of secondary metabolites using hairy root culture techniques. Rhodiola sp. is widely distributed throughout the Arctic regions of the Northern Hemisphere, with several species having significant medicinal properties. The article discusses the possible use of hairy root cultures for the production of Rhodiola secondary metabolites, including salidroside and rosavins, which have demonstrated significant pharmacological activity in various studies. The use of elicitation and genetic engineering techniques to boost secondary metabolite production in Rhodiola hairy roots is also explored. Overall, the article highlights the potential of Rhodiola hairy root cultures as a valuable source of secondary metabolites with medicinal properties. However, despite some studies Rhodiola hairy root induction and culturing still remains highly unexplored.

• Fruit drop: The role of inner agents and environmental factors in the drop of flowers and fruits

  13-23.

  J. Racskó

  G. B. Leite

  J. L. Petri

  S. Zhongfu

  Y. Wang

  Z. Szabó

  M. Soltész

  J. Nyéki

  Views:

  1744

  The basic conditions of fruit set (synchronic bloom, transfer of pollen, etc.) still do decide definitely the fate of the flower (Cano-Medrano & Darnell, 1998) in spite of the best weather conditions (Stösser, 2002). Beyond a set quantity of fruits, the tree is unable to bring up larger load. A system of autoregulation works in the background and causes the drop of a fraction of fruits in spite of the accomplished fertilisation and the equality of physiological precedents (Soltész, 1997). There are also basically genetic agents in action. The further development of fruits maintained on the tree depends mainly on the growing conditions (e.g. water, supply of nutrients, weather adversities, pruning, fruit thinning, biotic damages, etc.), which may cause on their own turn fruit drop especially at the time of approaching maturity.

• Effects of Foliar Nutrition on Onion Seed Storage under Controlled Atmosphere

  101-110.

  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:

  489

  Storage of fresh fruits and vegetables prolongs their usefulness. The principal goal of storage is to preserve the commodity in its most useable form for the consumer. The extension of storage life and the improvement of quality of fresh fruits and vegetables can be supplied by harvesting at proper maturity, control of post-harvest diseases, chemical treatments, refrigeration, controlled and modified atmospheres. 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 onion seeds and storage under controlled atmosphere. The germination percentages were 85.50, 86.85, 83.75 and 82.15 for CA1, CA2, CA3 and CA4, respectively. Water content of onion seeds was significantly increased with decreasing storage temperature in all controlled atmospheres. Water content values were 4.48, 4.40, 4.55 and 4.54 for CA1, CA2, CA3 and CA4, respectively. There were significant decreases in water content with increasing exposure periods. The lowest water content was recordednfor the exposure periods of 120 and 240 days. Catalase and peroxidase activities were decreased with the decreasing of storage temperature, whereas malondialdehyde content was increased. The exposure for 120 days recorded the highest catalase activity. The highest value of peroxidase (11.72) was recorded for CA2. Peroxidase activity increased as exposure period increased until 120 days and then decreased. Cold storage temperature (5°C) showed the highest malondialdehyde content followed by room temperature. The CA2 showed the lowest malondialdehyde content compared with other controlled atmospheres. The exposure period of 120 days had the lowest malondialdehyde content.

• Total anthocyanine content and antioxidant density of some Hungarian sour cherry varieties

  109-111.

  Zs. Veres

  I. J. Holb

  J. Nyéki

  Z. Szabó

  M. G. Fári

  Views:

  1934

  Evidence suggests that a diet high in fruits and vegetables may decrease the risk of chronic diseases, such as cardiovascular disease and cancer, and phytochemicals including phenolics, flavonoids and carotenoids from fruits and vegetables may play a key role in reducing chronic disease risk. Recent research has proven that sour cherry (Prunus cerasus L.) is a valuable natural source of some bioactive compounds important in human health preservation. In our work, we identified the total antioxidant activity, anthocyanine content and "antioxidant density" of sour cherry varieties named "Újfehértói fürtös", "Debreceni bőtermő", "Kántorjánosi" and "Érdi bőtermő" and those of the "Bosnyák" sour cherry clones. "Antioxidant density" is a biological value indicator obtained in a synthetic way, which indicates the antioxidant capacity of the particular food, e. g. fruit and vegetable, related to 1 Calorie.

• Review on rain induced fruit cracking of sweet cherries (Prunus avium L.), its causes and the possibilities of prevention

  27-35.

  G. Simon

  Views:

  1265

  The rain induced fruit cracking is a big, serious and costly problem for cherry growers. Cracked fruits lose their value and they are not marketable because of the poor fruit quality. Cracked fruits have different storage diseases and shorter storage and shelf life.

  There are many influencing factors of the cherry fruit cracking such as: water uptake; fruit characteristics (fruit size, fruit firmness; anatomy and strength of the fruit skin, stomata in fruit skin, cuticular properties, osmotic concentration, water capacity of the fruit pulp, growth stage of the fruit,); orchard temperature and other environmental conditions;

  The most effective protection technique is the plastic rain cover over the tree rows. The installation of these equipments is too expensive for the cherry growers. That is the reason why researchers tried to find other less expensive and sufficiently effective ways against the Lim induced fruit cracking.

  Several calcium formulas: calcium chloride (CaC1,), calcium hydroxide (Ca (OH)₂) and calcium nitrate (Ca(NO₃)₂ ) can be sprayed in appropriate concentration. Spraying with other mineral salts (aluminium and copper salts, borax) and PBRs (Plant Bioregulators) may be also effective to reduce fruit cracking.

• Cultivars, marketing and integrated Production of apples in the Czech Republic

  87-92.

  J. Blazek

  Views:

  243

  Development in apple production in the Czech Republic has been adversely effected during a few recent years by escape of capital investment from the agrifood industry (due to privatisation, restitution and transformation). On the other way round the competition on the domestic market is much higher than it was before because of unlimited import of subtropical and tropical fruit and some import of traditional fruit species as well. Therefore fruit growers are very much concerned in any possible means (which are not economically feasible) to be more competitive. One of the most common approach is the use of new cultivars bred in the country which are resistant or tolerant to diseases and offer better quality both for fresh market and processing. Another way for increasing competition ability for fruit growers is the join and mastering of integrated production which also considerably improve the quality of fruit as far as aspects of health are meant.

   

• Effect of postharvest sodium benzoate treatment on some fruit parameters of two organic apple cultivars

  35-37.

  B. Molnár

  Sz. Szabó

  Á. Veres

  I. J. Holb

  Views:

  1102

  The aim of this study was to investigate the effect of postharvest sodium-benzoate treatment on some fruit parameters of two organic apple cultivars (’Topaz’ and ’Florina’). Assessments were made at three times during storage: 17 November 2019, 20 December 2019 and 23 January, 2020. During every assessment dates, each fruit was observed separately, and determined the proportion of i) healthy fruits (%), ii) post-harvest fruit rot diseases iii) fruits with mechanical injury (%), iv) fruit with russetting (%), v) damage of codling moth and vi) Ca-deficiency symptoms. In addition, fruit weight (g) was measured at each assessment date. Sodium benzoate reduced the fruit decay and the proportion of healthy fruit was higher in this treatment compared to water treated fruit. This effect could be seen in all assessment dates and on both cultivars. Effects on other parameters were various according to cultivar and assessment dates. Loss of fruit weight was similar in both treatments and cultivars compared to control treatment.

• Ecotoxicology of Copper in Horticultural Soils: A Review

  7-18.

  N. Elhawat

  T. A. Alshaal

  S. Kratz

  É. Domokos-Szabolcsy

  H. R. El-Ramady

  J. Prokisch

  P. Eszenyi

  A. Sztrik

  B. Babka

  M. G. Fári

  Views:

  792

  Nowadays, the world is facing the problem of environmental pollution because of the increase of man’s needs requires development in life activities, progress industrialization, transportation tools, enhancement of agriculture and exploitation of natural resources. Soil and water resources are extremely exposed to pollution from different aspects. Agrochemicals in particular, have created severe problems, since they release thousands of chemicals to the environment. Several studies on the effect of environmental pollutants on agroecosystem have been carried out. On the other hand, the importance of trace elements as environmental pollutants is well known and well documented in literature. Cu contamination to agricultural soils has been accelerated due to its wide and repeated use in agriculture and horticulture as fertilizers or fungicides to protect vines, citrus trees, and other fruit crops against fungus diseases. Applied Cu from different agrochemical sources to agroenvironment may be adsorbed and are transported to the groundwater table and pollute it besides polluting the soils. The use of Cu-based fungicides in vineyard soils is widely documented worldwide. It has been found that many countries contain concentrations in excess of 100 mg kg−1. Importance of study of transport of Cu arises due to the fact that Cu is absorbed in soils and also reaches the groundwater table, thus polluting both soil and ground water. It is often more important to be able to estimate the mobile fraction, the readily soluble fraction, the exchangeable fraction, or the plant available fraction of Cu content of a soil as a more direct indication of the likelihood of deleterious or toxic effects on soils and groundwater. Therefore, the aim of present work was to highlight the behavior and ecotoxicological effects of copper on horticultural soils.

• Comparative study of some nutritionally important components on different cabbage (Brassica oleracea L.) genotypes

  81-84.

  É. Sárdi

  E. Tordai

  E. Németh

  É. Stefanovits-Bányai

  Views:

  503

  Vegetables of Brassicaceae are especially important because of their inner values, which play a provably positive role in curing and preventing diseases. Cabbage (Brassica oleracea L. convar. capitata provar. capitata) is still today one of the most frequently consumed green vegetables, which is known to brake the absorption of carcinogenous substances and to obstruct cell mutation. Different cabbage cultivars were compared growing under the same circumstance. The level of different carbohydrate fractions and some biologically active quaternary ammonium compounds were determined. In all cases we analyzed the antioxidant capacity of samples characterizing the free radical scavenging capacity.

  Clearly detectable significant differences were found between the varieties tested, which appeared suitable for selecting the most precious varieties for human nutrition.

• 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:

  13602

  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.

• Selenium enriched vegetables as biofortification alternative for alleviating micronutrient malnutrition

  75-81.

  H. R. El-Ramady

  N. Abdalla

  M. Fári

  É. Domokos-Szabolcsy

  Views:

  953

  There is a very difficult equation for malnutrition and over-consumption. That means malnutrition even of vitamins and/or minerals (Ca, Cu, Fe, I, Mg, Se and Zn, vitamin A) affects more than two billion people worldwide, largely due to low concentrations or poor bioavailability of the nutrients in the diet. In some developed countries in contrast, over-consumption, particularly of over-refined cerealbased foods, has contributed to the development of an epidemic of metabolic diseases. So, producing nutritious and safe foods sufficiently and sustainably is important target at the same time challenge of modern agriculture. In the past, great efforts have focused only on increasing crop yields, but enhancing the concentrations of mineral micronutrients has become an urgent task. The main daily food source is the staple crops specially in developing countries of the world, i.e., wheat, rice, cassava, beans, sweet potato or maize. These kind of plants are often deficient in some of mineral elements. Thus, the increasing of bioavailable concentration of micronutrients in edible crop tissues (via biofortification) has become a promising strategy in modern agriculture, providing more nutritious foods, to more people, with the use of fewer lands. Biofortification of these trace elements can be achieved application with agronomic process such as soil or foliar fertilization or crop breeding even conventional technic and/or genetic engineering. This review highlight progress to date and identify challenges faced in delivering biofortified vegetable crops as well as the agronomic approaches and tools to improve crop yield and micronutrient content of food crops.

• Genetic variation in the rose pathogen Marssonina rosae estimated by RAPD

  63-67.

  G. Werlemark

  B. U. Carlson-Nilsson

  C. G. Davidson

  Views:

  353

  Blackspot, caused by the fungus Marssonina rosae (Diplocarpon msae), is one of the most devastating and widespread diseases in garden roses, and it has as yet not been fully characterized in molecular terms. In this initial study we used RAPD analysis to investigate the genetic diversity among and within a few geographically diverse groups of single-spore isolates of M. rosae. DNA was extracted from in vitro­grown mycelia of 1 I single spore isolates grown on PDA medium. High levels of polymorphism were detected among the isolates. They clustered into three distinct groups: Group !consisted of isolates from eastern North America plus a European isolate (Germany), Group 2 included isolates from southern Sweden, and Group 3 included the isolates from Manitoba, Canada. The greater similarity of the environmental conditions in eastern North America and Europe as compared to the Canadian prairies suggest that. climate and weather could be key factors in influencing the potential race structure of M. rosae. However, variations among closely situated sites, e.g. southern Sweden, also occurred.

• Mutation induction in sweet basil (Ocimum basilicum L.) by fast neutron irradiation

  30-38.

  E. Enkhbileg

  A. Fenyvesi

  B. Bíró

  M. G. Fári

  E. Kurucz

  Views:

  795

  Basil species are highly sensitive to exterior environmental conditions and its consequences lead to great economic and agronomic losses. In this research, a mutation method was optimized out for creating a new variety of Ocimum basilicum L., which could tolerate the extreme/extraordinary climatic circumstances or biotic stresses, such as fungal diseases. Fast neutron irradiation was performed on the Hungarian commercial variety seeds with doses of 5 to 60 Gray and grown into fully developed plants. Numerous phenotypical changes like deformed congestion, leaf mutation, and low growth occurred, especially at higher dosages. Then to confirm whether the plantlets had mutation or not, and to detect the molecular variation and relationship, fingerprinting profiles of the developed mutant regenerants and donor plant have been assessed using ISSR markers. 115 loci were yielded, ranging from 0.2 to 1.5 kb, out of which 110 loci were polymorphic in nature, representing 95.6% polymorphism. The most suitable primer to determine the genetic diversity within the Ocimum species was the UBC-856 with 0.42 PIC and 4.1 MI values.

• Incidence of fungal diseases on leaves of apricot and plum cultivars in Hungary

  29-31.

  I. J. Holb

  G. Drén

  S. Thurzó

  Z. Erdős

  M. Soltész

  J. Nyéki

  Z. Szabó

  Views:

  1396

  In this two-year study, incidence of Polystigma rubrum on plum, and Apiognomonia erytrostoma on apricot were evaluated on several stone fruit cultivars in Hungary. Results showed that most apricot cultivars expressed symptoms caused by A. erytrostoma, graded between 2 and 3 (10-50%) by the end of the summer in 2005 and 2006. The most tolerant apricot cultivars were Budapest and Mandulakaj­szi while the most susceptible ones were 'Magyar kajszi' and 'Piroska'. Assessments made on plum showed that most of the plum cultivars were tolerant or lowly susceptible to P. rubrum such as 'Ageni', 'Althann ringló', 'Bluefre', 'Cacanska najbolja', 'Silvia', 'Ruth Gerstetter', 'Tuleu gras' and 'Utility'. The most susceptible plum cultivars to P. rubrum were 'Besztercei clones' and 'Debreceni Muskotály'.

• The effect of cluster thinning, cluster tipping, cluster shredding and defoliation at the flowering on the vegetative and generative vine performance from Kékfrankos Cv.

  63-68.

  I. Fazekas

  J. Göblyös

  Gy. D. Bisztray

  G. Zanathy

  Views:

  530

  The cluster thinning is a method of the yield regulation.With the removal one part of the clusters, the yield pro leaf area will be lower, hereby the grape and wine quality will be improved. The regulation of the yield can lead to further advantages: the ratio of the vegetative and generative performance of the vines will improve, the condition of the plants will better, the number of the physiological diseases can be reduced and the growth of the shoots and roots can be promoted. The grape growers make the cluster thinning almost exclusive by creating one cluster shoots. Usually the upper clusters are removed, because the sugar content of these second or third clusters will be lower. The cluster thinning is an easy task, can be done without special skills. It is an effective method improving wine quality, but its use can lead to other problems. The grapes try to compensate the removed clusters. Therefore the clusters will be bigger and thicker, but more sensitive to bunch rot. Moreover the treatment is expensive, because it needs manual work. It is worth to get acquainted and try the new yield regulation methods, which can help to avoid the occurring problems. Our aim is to show the results of our experiment, which was carried out in Eger, examining the red grape cultivar Kékfrankos. During our 4 years long experiment we compared the effects of cluster thinning, cluster shredding, cluster tipping and defoliation at the flowering, on the vegetative and generative vine performance.

• Yield loss caused by fruit rot fungi on sweet cherry in Kyustendil region, Bulgaria

  49-52.

  B. Borovinova

  Views:

  295

  The aim of the study was to determine the incidence of fruit rot caused by several fungal pathogens from 1999 to 2003. The study was conducted in three sweet cherry orchards at the Institute of Agriculture (Kyustendil, Bulgaria). One copper containing fungicide was applied in late autumn and early spring. During the growing seasons, 2-5 sprays were applied against fungal diseases. Trees were not sprayed specifically against fruit rot during the growing season, with the exception of 1999, when a spray of myclobutanil was applied after a long rainy period during the maturity of fruits. In one orchard, two nitrogen fertilization treatments were also prepared. In treatment 1, trees were fertilized with ammonium-nitrate 10 g/m² and in the other treatments trees were not. Incidence of the five most important fruit rot pathogens, Monilinia fructigena, M. laxa, Botritys cinerea, Alternaria alternata and Rhizopus stolonifer was assessed in all orchards. The most severe yield loss (14.80 %) was measured in 1999, when weather conditions were the most favourable for fruit rot development. In this year, brown rots (M. fructigena and M. laxa) caused the highest damage (9.22 and 4.04 %, respectively) out of all assessed fruit rot pathogens. In all other years, yield loss was significantly lower than in 1999. In 2002, A. alternata caused the main fruit rot (4.46%) and all other fungi were less important, while in 2003, B. cinerea caused considerable yield loss (2.28 %) compared to all other fruit rot pathogens. Experiments on fertilization showed that nitrogen significantly increased fruit rot damage in 1999, 2001, 2002 and 2003. The effect of nitrogen fertilization was higher in years with rainy periods around harvest (1999 and 2002) compared to more dry years (2000 and 2001). Results were compared with similar studies and biological interpretations of the results are discussed.

• Comparison of Xanthomonas arboricola pv. juglandis isolates from walnut trees grown in Romania and Hungary

  65-69.

  A. Bandi

  Views:

  484

  Among diseases that affect walnut, bacterial blight is considered the most important one in all walnut growing areas both from Hungary and Romania. For the determination of susceptibility/resistance of walnut cultivars in our posterior work planned, 61 bacterial isolates were collected from walnuts showing symptoms of blight, with the purpose of isolating Xanthomonas arboricola pv. juglandis (Xaj). The characteristic Xaj colonies, frequently present as saprophytes in the infected plant tissues, were separated from other bacteria according to their morphology, yellow colour, hydrolysis of starch, and oxidation of glucose. All isolates were tested for pathogenicity by hypersensitive reaction on tobacco leaves (Nicotiana tabacum L.), bean pods (Phaseolus vulgaris L) and unripe nuts (Juglans regia L.). Determination of taxonomy of the selected isolates denotes a possible subdivision (races, biotypes) of Xaj occurring in different geographical areas, API 20NE and API 50CH kits were used. Hungarian and Romanian strains showed a high degree of similarity of carbohydrate utilization but slightly differed from the type strain. All were Cu-sensitive.

• Fire blight (Erwinia amylovora) susceptibility of old Hungarian apple cultivars

  35-38.

  M. Tóth

  K. Honty

  M. Hevesi

  Views:

  474

  The aim of the Hungarian apple breeding program started in the Department of Fruit Science was to find resistant apple cultivars against major diseases (scab, powdery mildew, fire blight). The outbreak of fire blight (Erwinia amylovora) in 1996 motivated us to search new resistant sources principally from old traditional apple cultivars. First of all, cultivars have been gathered since 1997 from Carpathia (Visk) and evaluated between 2001 and 2003. In this recent study evaluation of resistance of old Hungarian genotypes to fire blight collected from the English National Fruit Collection (Brogdale, Faversham) is presented.

  13 old Hungarian apple cultivars in 2002, and 38 genotypes in 2005 have been evaluated. We used `Idared' and 'Jonathan M41' as susceptible controls and 'Liberty' and 'Remo' as resistant ones. Shoots of two-year-old potted plants were inoculated with a mixture of virulent E. amylovora isolates (Ea2, Ea60, Ea67) at a concentration of 5 x 10⁸ cells/ml. Resistance of apple cultivars was evaluated weekly, four times after inoculation by disease severity of symptoms. Numbers of bacterial colonies in 1 cm length shoot were determined in the fourth week after infection.

  8 cultivars in 2002 and 9 cultivars in 2005 displayed notable resistance to fire blight based on one-year data. Based on the coincident data of both years, out of the cultivars collected also from Carpathia ‘Pónyik', and `Sikulai' were found to be resistant and gene sources additional old Hungarian valuable apple genotypes could be selected: `Szabadkai szercsika' and `Tordai piros !davit'. The cultivar `Szemes alma' originated from Visk has proved to be recurrently resistant.

  The number of bacterial cells in shoots of the investigated cultivars correlated with the severity of symptoms. With this method, which was introduced by us earlier, we can screen cultivars displaying weak visible symptoms, which cannot be proposed as a source of resistance because of their latent infection.