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  • Development in intensive orchard systems of cherries in Hungary
    76-86.
    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.

  • Freeze Susceptibility of Fruit Buds in 67 Apple cultivars in Hungary
    29-35.
    Views:
    121

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

  • Bee pollination and association of apricot varieties
    20-24.
    Views:
    190

    Apricot yields are highly variable according to the season. The variation is caused mainly by the adversities during the critical processes of floral biology, i.e. blooming and fertilisation. On the basis of information concerning blooming time and mutual compatibility relations of apricot varieties a system of securing regular and adequate yields has been developed.

    Winter frosts of the continental type are well tolerated by most of the apricots, however, after the end of rest period, flower buds are loosing frost tolerance, 'rapidly.

    Being one of the fruit species blooming earliest during the early spring, apricot start to bloom in Hungary around the end of March or early April as a mean of many years, but it also happened, exceptionally that apricot started to bloom at February 20 (at Letenye South Hungary). The early season, exposes the floral organs to frost injuries. As a consequence, apricot orchards on the Great Plain produce low yields in 3 years, intermediate yields in other 3 years out of a ten-year-period.

    Moreover, weather conditions during the blooming period are often unfavourable for pollination. Cool, windy and rainy weather prevents the flight of insects and on the other hand, warm spells shorten the blooming process, nectarines and stigmata get dry and the female gametes loose viability before effective pollination occurres.

    The fertility of individual cultivars are meeting different obstacles. Apricot cultivars differ greatly in the rate of flowers bearing underdeveloped pistils, which may attain even 60% (e.g. Orangered). New commercial cultivars are often self-incompatible. Local varieties of that type in Hungary are the „óriás" varieties (e.g. Ceglédi óriás, Szegedi mammut), and the new hybrid Ceglédi Piroska. Many of the cultivars are variable in their self-fertility (partially self-fertile): Budapest, Harmat, Korai piros, Mandulakajszi.

    Inter-incompatibility is also known in apricots. The „óriás " varieties do not fertilise each other. During the growth of fruits, cool spells (2-4 °C) caused severe fruit shed in Ceglédi óriás.

    Apricot flowers produce pollen and nectar at average rates related to other fruit species, thus bees are attracted sufficiently. Bee visits are very variable according to growing site and season. Most of the bees are pollen gatherers but sometimes nectar suckers are in majority. Bee pollination is necessary not only for the self-incompatible varieties but also to enhance the yield of self-fertile varieties.

    Taking the blooming and fertility relations of the cultivars into account, plantations should not exceed two rows to a particular self-incompatible varieties, and possibly two different polliniser varieties are suggested to be planted as flanking the block in question.

    In commercial plantations 2 to 4 bee colonies per hectare are proposed to move for the whole blooming period.

     

  • Healthcare values and potential uses of the new Hungarian apple varieties on the basis on fruit analysis
    25-28.
    Views:
    179

    Biological active compounds and valuable characteristics of some apple varieties and candidates were measured in our trials. Fruits of ’Rosmerta’, ’Hesztia’, ’Cordelia’ and ’Artemisz’ are recommended to enrich the Hungarian assortments for fresh consumption and choice of new tastes. Based on examined parameters it can be assumed that novel Hungarian resistant varieties are suitable for juice and fruit concentrate production, and due to high pectin content of their remaining pomace these varieties can be raw material of pectin production as well as they are also suitable for jam production mixed with other fruit species. Furthermore, functional food industrial product having high quality can be produced by using novel resistant varieties because of their high pectin and polyphenol content. Beside of their high market value their suitability for growing among orchard conditions is confi rmed by lower costs of production because of less plant protection treatments.

  • Economic figures of sour cherry production at national level of Hungary
    107-109.
    Views:
    158

    After the political changes of 1989, economical processes impaired heavily the Hungarian fruit growing branch, more particularly production of sour cherry. Paralleling with the increasing mass of production, producer’s prices dwindled drastically. At present, Hungarian growers cannot cover the costs of production, nay, hardly raise income. My purpose was to analyse the cost and income relations of the sour cherry branch during the period of 2002-2009 years in order to find out what are the decisive features, which reveal the trends to be considered. The data presented in the paper are means of a heterogeneous population of values, which cannot be utilised for immediate use in management, but they may reveal the challenges and tendencies of economics of the branch.

  • Training and maintaining spindle crowns in cherry production
    51-53.
    Views:
    221

    In cherry production all over the world, intensification of the technology is the main objective of research. Small crowns and high planting densities are aimed to attain high yields per hectare and easier harvesting. Rootstocks of reduced vigour for cherries are more difficult to find than in other fruit species, and the rejuvenation of fruiting structures by pruning is aggravated by the reduced vigour. Intensity of the technology ought to be achieved by a thoughtful application of the technological elements (timing of pruning by various intensity) moreover, by finding different policies for individual varieties. Sweet cherry varieties dominating the assortment proved to be very variable regarding their growing habits. In our experiment, we dealt with the slender spindle and free spindle forms, and how to train the trees to develop and to maintain the desirable form depending on the respective variety in order to achieve the right load of flower buds and yields repeatedly. In this paper, we examine the most important practical issues with the training and maintaining of the crowns of cherries with circular projection and central axis grafted on Prunus mahaleb rootstocks

  • Factors affecting apricot fruit antioxidant capacity and mineral element contents
    95-99.
    Views:
    201

    Several epidemiological studies revealed that the consumption of antioxidant compounds and the risk of atherosclerosis, increased blood pressure or cancer are inversely proportional. The individual amounts and relative proportions of macro- and micro elements present in food is also of great consideration since these are involved in a wide range of physiological processes including the influence of the redox homeostasis. The antioxidant power and mineral nutrient content of fruits might be affected by several factors including genotype, ripening stage, year-effects or a wide range of environmental conditions. This study was carried out to survey the antioxidant power and mineral element content in fresh fruits of apricot and analyse some genetic and environmental factors that may have important contribution to the inner content of apricot fruits. In addition, the influencing effect of the extraction procedure used for antioxidant analyses was also tested. Our analyses indicate that a considerable fraction of antioxidant capacity is attributable to the hydrophilic antioxidants. The genetic background has crucial importance in determining apricot fruit antioxidant capacity and mineral nutrient content; however, the growing season and the ripening time of fruits may have also important effects.

  • Organic apple growing using sanitation treatments against apple scab
    11-13.
    Views:
    124

    Effects or sanitation practices were evaluated on primary and autumn infection by Venturia inaequalis in an organic apple orchard at Eperjeske on the moderately scab-susceptible apple cultivar Jonathan in 2005 and 2006. Evaluated sanitation practices were: i) collection of fallen leaves in autumn; ii) destroying fallen leaves by disc cultivation in autumn; iii) spraying fallen leaves with 2% lime sulphur in autumn; iv) spraying fallen leaves with 2% lime sulphur in autumn and then collection of fallen leaves in autumn; and v) untreated control. In both years, most sanitation practices reduced significantly (P< 0.05) scab incidence in the primary infection periods compared to untreated control. The highest leaf scab incidence was observed in the untreated plots (26:2 and 24.3% in 2005 and 2006, respectively), while the lowest was in the treatments of spraying fallen leaves with 2% lime sulphur combined with collection of fallen leaves (11.7 and 12.3% in 2005 and 2006, respectively).

  • Effect of foliar fertilization on leaf mineral composition, sugar and organic acid contents of sweet cherry
    45-48.
    Views:
    206

    Influence of a three-year-long foliar fertilization on mineral composition of leaf, content of sugars (glucose, fructose, galactose and sucrose) and organic acids (citric, malic and fumaric acid) of sweet cherry (Prunus avium L.) fruits was studied. The experiment was conducted during 2005-2007 in West Hungary on mature cv. `Germersdorfi 3' grafted on Prunus mahaleb rootstock, planted in 1999. Trees spaced 7 x 5 m, and growing in a calcareous chernozem soil. Trees were foliar-fertilized with potassium (K) as KNO3 and calcium (Ca) as Ca(NO3)2. Potassium spraying was carried out 3 (K1) and 5 (K2) while calcium was applied at 3 (Ca 1), 5 (Ca2) and 6 (Ca3) weeks after full bloom. Beside fruit analysis, complete soil and leaf analysis were done to study the rate of nutrient uptake and its effects on fruit quality. Contents of nutrients of soil and leaf were determined by atomic absorption and spectrophotometric method, while sugars and organic acids in fruit were determined by HPLC. The applied treatments (except K1) had been increasing leaf K significantly compared to the control till ripening. Most of treatments had no significant effect on Ca content of leaf till ripening. From applied treatments only the boron treatments had significant increasing effect on contents of all examined sugars, compared the control. Furthermore, the effect of calcium spraying on the contents of organic acids was significant.

  • Effect of hydroponic and peat-free media in transplant production of Rudbeckia hirta varieties under different photoperiodic lighting and their photosynthetic parameters
    110-117
    Views:
    367

    The purpose of this research was to determine the effects of varieties, different light conditions (short day, long day, natural short day with light pollution), and different growing media (perlite, peat-free, peat-based, aeroponics system) on Rudbeckia hirta plant production under controlled conditions (greenhouse). The morphological effects of each treatment (photoperiodic lightings and media) on different Rudbeckia varieties determined at 11 weeks-old ’Napfény’, ’Toto Gold’, ’Autumn Colors’, ’Prairie Sun’ and 16 weeks-old ’Napfény’. Plantlets received 12 hours daylight did not initiate flowers, remained stage of the leaf rosette in case of all varieties. The 14 hours light treatment in the aeroponics system and the same treatment in perlite and control (natural short day with 14 hours light pollution) plantlets had developed inflorescences or flower buds. The inflorescence axis of ‘Napfény’ was appeared at 13 weeks under long-day conditions, with 1.7 (perlite) - 2.7 (aeroponics) flower buds in 16 weeks. ’Toto Gold’, ’Autumn Colors’, ’Prairie Sun’ varieties developed inflorescences at 8 weeks, 14 hours aeroponics system resulted in the most of flower buds (’Toto Gold’: 6.5, ’Autumn Colors’: 3.25,’Prairie Sun’: 4.8 flower buds) at 11 weeks. Long daylight manipulation could be minimized crop times and achieved flowering potted plants at 11 weeks. The peat-based and peat-free media effect was observed on ‘Autumn Colors’. The number of leaves of peat-free ‘Autumn Colors’ transplants (16.8-20.3) was significantly higher than peat-based media (13.5-15.5). Other morphological parameters were not affected by the media treatments.

  • Comparison of Xanthomonas arboricola pv. juglandis isolates from walnut trees grown in Romania and Hungary
    65-69.
    Views:
    262

    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.

  • Precision geoinformatical system of the pear gene-collection orchard
    43-50.
    Views:
    202

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

  • Sunburn incidence of apples is affected by rootstocks and fruit position within the canopy but not by fruit position on the cluster
    45-51.
    Views:
    221

    Authors investigated sunburn incidence of apples on the combinations of three different growth inducing rootstocks (M.9,MM.106 and seedling) and five varieties (‘Smoothee’, ‘Golden Reinders’, ‘Granny Smith’, ‘Gloster’ and ‘Jonagold Jonica’). Symptoms were classified as sunburn browning, sunburn necrosis and photooxidative sunburn. The frequency of symptoms was recorded at various parts of the canopy (N, E,W, S, and lower canopy, upper canopy) and on the cluster (terminal, lateral). Cultivar susceptibility varied between 0.30 and 5.65% on M.9 rootstock, ‘Granny Smith’ seemed to be the most susceptible cultivar whereas relatively low percentage of damaged fruit was observed for ‘Gloster’. On MM.106 and seedling rootstocks, damage level was significantly lower than on M.9. Remarkable differences were not observed in the share of the three sunburn types between cultivars. The most common symptom observed was sunburn browning. Far less fruit was affected by sunburn necrosis and photooxidative sunburn. Photooxidative sunburn symptoms were not found on ‘Granny Smith’ and ‘Gloster’ fruits on MM.106 rootstock. Latter cultivar did not show sunburn necrosis symptoms either. With increasing growing vigor of the rootstocks the share of sunburn browning increased. Fruits with sunburn symptoms were found in a great majority on theW quadrant of the trees. This was true for all cultivars. Remarkable differences in the location within the canopy of affected fruits between the three types of sunburn were not observed. Specific distribution of sunburned fruit was observed along the vertical axis of the canopy, too. Most of the damaged fruit were found in the upper canopy. This is particularly true for trees on vigorous stocks such as MM.106 and seedling. On M.9 rootstock, depending on cultivars 5.9 to 38.9% of sunburned fruit was located in the lower canopy. Most common symptom in the lower canopy was the sunburn browning, however symptoms of sunburn necrosis were not found at lower canopy level. Low rate of photooxidative sunburn was observed such lower canopy conditions. Sunburn incidence was very similar on king or side fruit. Significant differences were not found in the share of each sunburn types between fruit positions on the cluster. This was not influenced by rootstocks either.

  • Study of Erwinia amylovora colonization and migration on blossoms of susceptible and tolerant apple cultivars
    15-19.
    Views:
    132

    The stigmata of detached flowers of susceptible and tolerant apple cultivars were inoculated with about 104 gfp labeled Erwinia amylovora . There were no apparent differences in the colonization, multiplication and survival of the bacteria on the stigmatic surface of the culivars. Bacteria were washed down to the hypanthium surface 24 hours after inoculation. The visual symptoms of the infection were the discoloration and shrinkage of the floral parts. The gradual browning associated with the infection appeared first on the surface of the hypanthium followed by the discoloration of the style. The color of the filaments turned into brown only 120 hours after the inoculation. Bacterial cells were not detected in the tissues of the styles and filaments. The traits of the hypanthium surface are of prominent importance in the progression of the infection. The wrinkled surface, the convex shape of the outer epidermal cell walls with thin cuticle and the sunken stomata helped to preserve a water film for a longer period providing medium for the motility of the bacteria in the susceptible cultivar. Bacteria were restricted to small water droplets on the flat and waxy surface of the hypanthium of the tolerant cultivar and only a few were able to enter the tissues.

    Large bacterium aggregations were detected in the intercellular spaces of the parenchyma of the susceptible cultivar 48 hours after the inoculation. In the next period the Erwinia amylovora cells gradually invaded the intercellulars of the hypanthium wall, the wall of the ovary and the pedicel. Low level of bacterium aggregation was found in the intercellulars of the tolerant cultivars. It is suggested that the progression of the infection was inhibited also by physiological factors.

  • Studies for using frameless plastic in the forcing of some ornamental crops
    148-150.
    Views:
    126

    On the basis of a six-year experiment a method was elaborated for forcing and off-seasons growing of tulips, narcissus and gladioli under frameless plastic cover. The advantages of this cheap energy-saving method are manifested in an improved quality of flowers and essentially in the earlier flowering. With this method mostly first-class flowers can be obtained immediately after the season of forcing in heated constructions with plastic cover, and anticipated outdoor flowering.

    The possibilities of applying the method are studied on further ornamental plant species (other bulbous plants, Paeonia lactiflora, annual ornamentals).

     

  • Comparison of honeybee behaviour in blooming fruit plantations
    147-151.
    Views:
    191

    Field observations were made on the fl ower visiting behaviour of honeybee foragers in commercial fruit plantations of apricot, Japanese plums, sour cherry, apple and pear. The number of inspected cultivars was 18. The intensity of fl ower visiting by honey bees was markedly different when data of different fruit species are compared. Most intense bee activity was registered on the Japanese plums, somewhat less on apricots, the intensity diminished signifi cantly with apples and pears. Our data presented on the honeybee visitation of Japanese plums can be regarded as new fi nding because no information has been available so far on the relative attractiveness of this fruit species compared to European fruit tree species. Japanese plums were somewhat more attractive to honeybees than apricot and much more attractive than sour cherry, apple and pear. The behaviour of honeybees as visiting the blooming trees displayed specifi c differences according to the fruit species (apricot, sour cherry, pear), which coincide largely with earlier results. It is notable that the fl ower visiting behaviour of honeybees on Japanese plums has been found to be fairly similar to the same on European plums.

  • Comparison of apples from organic and integrated farming
    15-18.
    Views:
    211

    Prima’, ‘Gala’, ‘Remo’, ‘Topáz’, ‘Idared’, ‘Releika’, ‘Resi’, ‘Rubinola’, ‘Rajka’, ‘Rewena’ and ‘Florina’ apple cultivars, both from organic and integrated farming, from Pallag and Újfehértó, were compared. Average size, weight, soluble solids, titratable acidity, total polyphenols, free radical scavenging capacity expressed as Trolox equivalent (TEAC), copper and zinc were determined at harvest and after cool storage. Organic apples were more acidic, while integrated fruits had mostly higher copper and zinc content. Total polyphenols and TEAC values did not show a significant difference as a function of farming technology. A principal component analysis shows the separation of provenances as well as stored and fresh apples. Results are considered as preliminary.

  • Test of the utility of apple retrotransposon insertion patterns for molecular identification of 'Jonathan' somatic mutants
    7-10.
    Views:
    171

    Up until today, apple sport mutants proved to be indistinguishable from each other and their progenitors at the molecular level using random amplified polymorphic DNA (RAPD), amplified fragment length polymorphism (AFLP) and simple sequence repeat (SSR) marker techniques. This is not surprising, since the genomes of these somatic mutants differ only in one or a few small regions that affect economically important characteristics, such as improved fruit colour, size, or flavour. In most cases, these genome differences are probably caused by retrotransposons which are able to convert their RNA transcripts to DNA with reverse transcriptase enzyme prior to reinsertion, but unable to leave the genome and infect other cells. Retrotransposon insertions can alter the expression of other genes and/or the structure of encoded proteins. The sequence-specific amplified polymorphism (S-SAP) technique is capable of revealing the genetic distribution of retrotransposable elements over the whole genome. The present study used this approach to try to characterize and distinguish 'Jonathan' somatic mutants via fingerprinting, which is an unsolved problem.

  • Work organization and economic analysis of the postharvest of an unique Hungarian product
    11-14.
    Views:
    124

    We have viewed a business in the south of the Great Plain Region from an economic point of view in 2004-2005. The main activity there is pear growing and storage. Four varieties of different time of ripening and storing are grown there. We have measured all the relevant activities, worked out a local normative and prepared a detailed technology. The economic evaluation was based on this data. Activities, like disinfection, pre-storage disinfection and selection, in-storing and out-storing, classification after storage, packaging, as well as loading trucks, were monitored by variety. Storage loss was determined and widely varied according to varieties, length of storage and time of out-storing. Different varieties resulted in different quality classes after storage. Price depended on the quality classes. Economic evaluation was carried out when all the relevant costs and revenues were known. Fixed and variable costs of storage were determined, break-even point was calculate and the market position of the product was evaluated.

  • Volatile constituents of Nepeta cataria L., N. glechoma Benth. and N. parviflora M. Bieb. from Hungary
    47-50.
    Views:
    120

    In the temperate zone live about 150 species of the Nepeta genus. Our investigations covered the examinations of the volatile oil containing species of the genus endemic in Hungary, Nepeta cataria and Nepeta parviflora. Latter is a relict of the ancient steppe-flora and endemic in Hungary as well. Phytochemical examination of the volatile oil containing plant material has also been carried out. Catnip growing in the Botanical Garden of PTE Department of Botany contained 0,67% volatile oil in May and 0,14% in November. Chemical character of the volatile oils were measured by gas chromatography/mass spectrometry and citronellol, citral-A, citral-B and geraniol components were identified. The composition of the oil of November samples shifted towards citronellol (65%). In both samples insecticide and repellent activity bearing compounds (+)-cis-p-menthane-3,8-diol, and (—)-trans-p-menthane-3,8-diol in 2-2.5 and 4-4.5% amount have been found. The catnip sample deriving from Germany contained a small amount of anetol, citronellol, neral, geraniol and geranial (6-13%), and possibly two isomers of nepetalactone in 23-31%.

    The Nepeta parviflora endemic in the Nagyvolgy valley near Nagykaracsony consisted of the same compounds in the investigated years (1998-2000). Its limonene, methyl chavicol, b-cariophyllene, b-selinene, b-cubebene, davanone, germacrene-D constituents have been identified. In the year 2000 different GC % of these compounds were detected in the different organs of the plants.

    The closely related species Nepeta cataria var. citriodora contained 83% citral, and the N. glechoma (= Glechoma hederacea) contained 41% a-cubebene, 20% patchoulenol, 7,7% spathulenol respectively. These compounds were identified by gas chromatography and gas chromatography / mass spectrometry.

     

  • Effect of the placement of self-incompatible apricot varieties on their yield in commercial plantations
    82-86.
    Views:
    142

    Earlier studies concerning self-, free- and cross- fertilization of apricot varieties grown in Hungary, proved the existence of self-sterile as well as self-fertile varieties within the recommended assortment. The self-sterile and partially self-fertile varieties should be planted in association with polliniser varieties, only. The present paper reports about the yields of trees of the widely grown, self-sterile local variety, Ceglédi óriás (Giant of Cegléd), depending on the distance of adequate polliniser trees. In the univarietal, 27 row-wide block of the relevant variety, an efficient polliniser, Magyar kajszi was planted to the 10th and 19th row. In the close vicinity, another block of polliniser, Rózsakajszi C. 320 was located. The number of fruits set per tree has been counted or estimated in two consecutive years. In both seasons, the yield of the Ceglédi óriás trees diminished with the growing distance from the nearest polliniser trees. Those trees in the center of the block, between the two (10th and 19th) rows of Magyar kajszi bore acceptable yield (40 kg/tree in 1987), however, considerable reduction of the number of the fruits set was stated already in the 4-5th row from the polliniser away. Similar gradient of fruit set was apparent in relation to the neighbouring block of Rózsakajszi C 320. The beneficial effect of the vicinity of polliniser varieties was obvious as far as the distance of the 10th row. Taking into consideration the self-sterility, the early blooming time and the poor fertilization of the variety Ceglédi óriás, a planting design of associating it with at least two polliniser varieties (e.g. Gönci magyar kajszi and Ceglédi bíbor) is highly recommended. On the basis also of earlier results, a proposal has been developed for the association of apricot varieties as recommendations for optimising yields. Blooming time, fertilizing potential, schedule of the picking season and market possibilities have to be considered simultaneously.

  • Improved clonal approaches to growing black locust (Robinia pseudoacacia L.) in Hungary: a case study
    53-56.
    Views:
    238

    In Hungary black locust (Robinia pseudoacacia L.) is considered as an important exotic stand-forming tree species and due to climate change effects its importance is increasing in many other countries. It has some desirable characteristics from both the practical and research standpoints. As a result of a partly new black locust selection programme new black locust clones were improved and a technology was developed for mass clonal micropropagation of juvenile trees. Clone trials with micropropagated plants were established in the country for evaluating the juvenile growth and the stem form of promising black locust clones under marginal site conditions. Significant differences (P<5%) were found for stem form value which partly verified the genetic gain of the selected clones against the common black locust. It was also proved that tissue culture could offer partly new prospects for the rapid mass cloning of selected genotypes.

  • Susceptibility of European pear cultivars to Venturia pirina Aderh. infection at a variety collection in Hungary
    41-47.
    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.

  • Water relations of apple and influence on fruit quality (minireview)
    59-63.
    Views:
    302

    The saving of soil water content and the improvement of adaptability of plants to periodical insufficient water and use of deficit irrigation technology become more important because of the occurrence of frequently dry periods. The water use efficiency of apples can be increased by the choice of appropriate rootstocks and determination of water requirement of varieties that depend on their growing periods and climatic factors. Depletion of soil water resources need to develop efficient irrigation techniques for quality apple production. A new deficit irrigation strategy (PRD) has been developed that based on partial water supply of root-zone. This does not result a decrease in the sizes and yield of the fruit. The larger fruit size and lower firmness in frequently irrigated trees can result in excessive internal growth stresses that cause higher rate of fruit splitting. Many studies revealed the relationship between irrigation and yield quantity. Recent researches investigate the effects of irrigation on apple fruit quality particularly on the colouration and post-harvest quality. Use of cooling irrigation improves the development of coluour an apple fruit but its schedule can influence on the incomes. Aroma volatiles are responsible for odour and contribute to overall flavour of the fruit and its processed products. Deficit irrigation had only affects some volatile aroma but no the all of concentrations in apple fruit. In the future the high apple quality for consumers could be provided with improvement of transpiration-yield model based on the water requirement of varieties and economic irrigation schedules.

  • Effect of boron fertilisation on the flavour of carrots - Applicability of organoleptic analyses to carrots
    51-54.
    Views:
    106

    Foliar boron fertilisation has had positive influence only on carotene content. Results were evaluated with chemical analyses and sensory tests. It has been observed that sensory tests are able to detect bitter flavour and also to measure its interaction with sweet flavour. Sensory tests for evaluation are generally used in the EU, also in the case of fruits and vegetables. With the aid of students and staff having received training and acquired practice, our University has the possibility to complete chemical analyses in such a way that satisfies modern demands, as well as facilitating the sale of the products on foreign markets.