Szerző szerinti böngészés "Papp, J."
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Tétel Szabadon hozzáférhető Anatomical relations of root formation in strawberry(2004-08-13) Papp, J.; Gracza, P.; Simon, G.Anatomical relations of root formation are traced throughout the life cycle of the strawberry plant from the germinating seed up to the runners of the adult plant. Histological picture of the root changes a lot during the development of the plant. First the radicle of the germ grows to a main root, which makes branches into side roots and later adventitious roots are formed on the growing rootstock or rhizome. The anatomy of the different types of roots is also conspicuously different. First tiny branches appear relatively early after germination on the seedling's radicle, but soon the hypocotyl of the seedling thickens and develops side roots, which are already somewhat stronger. During this interval, the first true leaves are formed. The 4th or 5th of them being already tripartite, and the initiation of new roots extends into the epicotylar region of the shoot. The second years growth starts with the development of reproductive structures, inflorescences and runners starting from the axils of the new leaves. Near the tips of the runners below the small bunch of leaves, new root primordia are initiated. The tiny radicle of the germ develops a cortical region of 5-6 cell layers. Cells of the central cylinder are even smaller than the cortical parenchyma and include 3-4 xylem and 3-4 phloem elements as representatives of the conductive tissue. Roots originating from the shoot region are much more developed; their cortical zone contains 17-20 cell layers, whereas the central cylinder is about half as large. In the next year, new roots are formed at the base of the older leaves. These roots differ hardly from those of the last season in size and volume, however, they are recognised by colour and their position on the rhizome. The roots of the last year are dark, greyish-black, and grow on the lower third length of the rhizome, on the contrary, the new ones, on the upper region, are light brown. Roots starting from the shoot or rhizome are, independently from their age or sequence, mainly rather similar in size and diameter, thus being members of a homogenous root (homorhizous) system, i.e. without a main root. Plants developed and attained the reproductive phase develop in the axils of the leaves runners being plagiotropic, i.e. growing horizontally on the surface of the soil. The runners elongate intensely, become 150-200 mm, where some long internodes bear a bunch of small leaves and root primordia on short internodes and a growing tip. Runners do not stop growing, generally, further sections of 15-25 cm length are developed according to the same pattern, with small leaves on the tip. The growing tip of the runners is obliquely oriented, and small, conical root primordia are ready to start growing as soon as they touch the soil. The roots penetrate the soil, quickly, and pull, by contraction, the axis of the runner downwards, vertically, developing a new rhizome. The short internodes elongate a little and start developing adventitious roots. At the end of the growing season, the plantlets arisen on the rooted nods of runners are already similar to the original plants with homogenous root system. On the side of the adventitious roots, new branches (side-roots) are formed. The root-branches are thinner but their capillary zone is more developed being more active in uptake of water and nutrients. The usual thickening ensues later.Tétel Szabadon hozzáférhető Anatomical relations of the leaves in strawberry(2005-03-14) Papp, J.; Gracza, P.; Szenthe, A.; Sárdi, E.; Simon, G.In the present study histology of the leaves of strawberry (Fragaria ananassa Duch.) variety Elsanta was the objective, which has been performed with the beginning of seedling stage, cotyledons, primary leaves and later true leaves, first cataphyll of the runner shoot as well as the bracteoles of the inflorescence. Structures of the leaf blade, the upper and lower epidermis, the petiole have been also observed. The leaf blade of cotyledons already contains a typical palisade as well as spongy parenchyma tissues, i.e. being bifacial showing a structure similar to that of the true leaf. However, the petiole displays differences from the true leaf. There are a narrow (4-5 layer) primary cortex and a tiny central cylinder. Primary leaves bear already hairs on the adaxial surface and the transporting tissue-bundles are recognised in cross sections having a "V" shape. The first true leaf composed by three leaflets is of a simple structure showing characters reminding of cotyledons and primary leaves. Leaves of intermediate size continue to grow, whereas their inner anatomy changes dramatically. In the central region of the leaflets, near to the main vein, a second palisade parenchyma appears, further on, transporting tissue bundles are branching in the petiole. Collenchyma tissues enhance the stiffness and elasticity of the petiole. Older true leaves develop thick collenchyma tissues around the transporting bundles being represented by increasing numbers. The doubled palisade parenchyma layers of the leaf blades are generally observed. The cataphylls of the runners have a more simple structure, their mesophyll is homogenous, no palisade parenchyma appears. It is evident that leaves grown at successive developmental stages are different not only in their morphological but also anatomical structure. There is a gradual change according to the developmental stage of the leaves.Tétel Szabadon hozzáférhető Cracking susceptibility of sour cherry (Prunus cerasus L.) in Hungary and relation to calcium application(2007-09-19) Simon, G.; Tóth, M.; Papp, J.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 (CaC1 2 ), calcium hydroxide (Ca (OH),) and calcium nitrate (Ca(NO 3 ) 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 (CaCl 2 ) and calcium nitrate (Ca(NO 3 ) 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 (CaCl 2 ) 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.Tétel Szabadon hozzáférhető Development and trends in fruit growing(2000-04-18) Soltész, M.; Nyéki, J.; Papp, J.; Hunyady, M.; Szabó, Z.In the development plan of fruit branch related to 2005, resp. 2010, the authors anticipate a 27, resp. 53% increase. They presage in the apple production a 40, resp. 61 % increase as attainable. As far as stone-fruits are concerned, the prognose amounts to 10, resp. 61% increment. (Except the sour cherry with 25 to 61% increase.) To hit the target they are planning until 2002' 4000 ha new plantations yearly. In their opinion there is a need of state subsidy (during the 3 years altogether) Ft 21 billion.Tétel Szabadon hozzáférhető The effect of different berries in human nutrition(2007-09-19) Tordai, E.; Nagy, E.; Stefanovits-Bányai, É.; Papp, J.; Blazovics, A.; Sárdi, É.The aims of this study were on the one hand to compare of examined compounds according to their importance in nutrition and human-health, and on the other hand we made preexperiments to investigate the relationships among antioxidant capacity and the endogenous substances which contribute the antioxidant status of the plants. The following species were involved in the experiment: raspberry, blackberry, black currant, elderberry and sour cherry. These fruits have potent health-promoting antioxidant power. Glucose, fructose, total phenol, formaldehyde and anthocyanin contents were determined in addition to ferric reducing ability. Our results reflected considerable differences in the measured parameters of the analysed species. In blackberries and elderberries the high antioxidant capacity is coupled with low carbohydrate content. Besides the formerly proven correlations between total phenol content, anthocyanin concentration and antioxidant capacity, these parameters also correlated with the measured formaldehyde concentrations, hereby we can follow the methylation /demethylation status of the plant.Tétel Szabadon hozzáférhető Effect of nitrogen dressings to Jonathan apple trees in a long-term experiment(2000-02-23) Papp, J.During the last three decades, diverse effects of nitrogen application on the performance of apple trees were studied in field and pot experiments at the Experimental Station of University of Horticulture and Food Industry. The basic experiment, using different rates of nitrogen in kg/ha (check, N-50; N-100; N-200; N-400; and N-800), was carried out for a period of 13 years, thus including almost the whole bearing period of Jonathan apple trees on M.9 rootstocks. The need of nitrogen in apple orchards on M.9 rootstock and soils with moderate humus content can be decreased considerably. Nitrogen application significantly increased leaf nitrogen and magnesium, but depressed leaf phosphorus and potassium content. With increasing doses of nitrogen fruit nitrogen content significantly increased and parallelly phosphorus and potassium content decreased. Even the lowest rate of nitrogen application decreased the red colouration of fruits. A direct negative correlation between nitrogen fertilzation and fruit firmness was not proved. No close and significant correlation between fruit quality parameters and the nitrogen content in leaves, sampled at different dates, was revealed.Tétel Szabadon hozzáférhető Floral bud development, blooming time and fertility relations of some Romanian apricot varieties in Hungary(2000-06-06) Szalay, L.; Papp, J.; Szabó, Z.; Nyéki, J.Due to the geographical situation of Hungary the introduction of late ripening apricot varieties holds great interest. In apricot production floral bud development during winter, blooming time, and the fertilisation properties are important factors. These characters were studied in six late ripening Romanian apricot varieties (Callatis, Comandor, Litoral, Selena, Sirena, Sulmona) in Szigetcsép representing the northern site of the lowland growing area. During the mild winter of 1997/98 the dynamics of floral bud development in the Romanian varieties was a few days slower during the whole examination period compared to Gönci magyar kajszi. Their meiotic divisions occurred between 1 and 5 February. Next winter the meiotic division started later at 28 February, due to the cold weather. In these conditions the dynamics of bud development was similar in all the varieties. Averaged over seven years blooming of the Romanian varieties started 1-3 days later than in Gönci magyar kajszi. All the Romanian varieties showed self-fertility to some extent, however, application of other pollen donor sources is necessary for the safety of production, with the exception of Callatis.Tétel Szabadon hozzáférhető Fruit production and research in Hungary - An overview(2004-11-15) Papp, J.; Nyéki, J.; Soltész, M.Hungary is traditionally a food producer country. 63% of its total land area can be cultivated. Horticulture is one of the fundamental agricultural branches. The country has a moderate continental climate, with a mean temperature of 10 °C. The average hours of sunshine ranges 1,700 to 2,100 hours. Under the geographical condition in the Carpathian Basin the chemical composition of the fruits has a good harmony. The total fruit acreage is 97,000 ha with a crop of 800,000 to 900,000 tons yearly. In 1982 1,934,000 tons of fruit crop were produced since then it has decreased. The most important fruits are apple, European plum, sour cherry and raspberry. The percentage of apple reaches almost up to 60%. In the new plantings sour cherry, apple and black elderberry is popular. The most important fruit-producing region is situated at the North-eastern part of the country. More than 40% of Hungary's fruit production is concentrated there. In ranking the 2 nd place is taken by fruit growing area in the middle of Hungary, where the production of stone fruits and small fruits has a considerable proportion. In the 70s and 80s of last century there was a developed research structure and wide range of research activity in Hungary. From that time the research capacity has considerably decreased first of all in the field of technological development. The main research area is fruit breeding and variety evaluation. Fruit scientists and fruit grower specialists are held together by the Hungarian. Society for Horticultural Sciences which has a membership in ISHS. Fruit researches and scientists having academic degree are belonged to the Horticultural Board of Hungarian Academy of Sciences.Tétel Szabadon hozzáférhető Hungaricum as a quality of fruits and fruit products(2003-06-24) Soltész, M.; Nyéki, J.; Szabó, Z.; Papp, J.The territory of the Hungarian state is largely suitable for the purpose of growing fruits of the temperate zone species. During the next decennia, the annual volume of Hungarian fruit production is expected to be around 1.1-1.3 million tons, from which some 15% is considered to be a produce of Hungary or "Hungaricum" (90 thousand tons of sour cherry, 50 thousand tons of apricot, 20 thousand tons of raspberry, 10 thousand tons of walnut). These fruits symbolise the country's special quality, which are worth to catch the interest the foreign consumers. The category of Hungaricum involves almost exclusively varieties of Hungarian origin as sour cherries, apricots, raspberries and walnuts, and they are representing outstanding qualities on the international markets. As for the fruit products the fruit brandies are eligible to be "Hungaricum" and are called exclusively "Pálinka". The Pálinka, provided to be distinguished with a geographic mark and will be competitive on the world market. Smaller quantities, though significant produce is represented by the deep frozen raspberry.Tétel Szabadon hozzáférhető Influence of strawberry and raspberry consumption on the antioxidant status of human body(2006-06-20) Szenthe, A.; Stefanovits-Bányai, É.; Blazovics, A.; Hegedűs, A.; Engel, R.; Sipos, B. Z.; Sárdi, É.; Papp, J.Several parameters influencing the antioxidant capacity were measured in our experiments to compare strawberry and raspberry cultivars. The analysed cultivars were: 'Honeoye', 'Elsanta', 'Onebor (strawberries) and 'Glen Ample', Fertődi zamatos', 'Mailing Expoit' (raspberries). Besides the determination of dry matter content the content of glucose, fructose, total phenol and anthocyanine, the reducing power, H-donating activity and total scavenger capacity were measured as well as the compound of mineral nutrients. Among the species and the cultivars, differences were obtained. These results call the attention to the features of cultivars and to count on the antioxidant-capacity describing values in case of consuming these fruits. In early spring and summer the consumption of strawberry and raspberry has a beneficial contribution to the antioxidant status of our body. In this respect these are more valuable than the year-long consumable apple. Accordingly, our measurements showed higher amount of sucrose, phenolic compounds and anthocyanine in raspberries, but strawberries contained more glucose and fructose and had stronger H-donating activity. It is worth to keep in mind that e.g. which cultivar contains more of certain compounds because of the strictly determined allowable dose in some diseases (e.g. diabetes).Tétel Szabadon hozzáférhető Knot formation by Pseudomonas syringae subsp. savastanoi on the in vitro shoots of Sorbus redliana(1999-09-13) Hevesi, M.; Papp, J.; Jámbor-Benczúr, E.; Gazdag, Gy.Two strains of Pseudomonas syringae subsp. savastanoi were isolated from Forsythia sp. and Nerium oleander in Hungary in 1997. The effects of growth regulators produced by the bacteria were studied in different experiments. The strains were co-cultured with Sorbus redliana in vitro shoots without being in contact with the plant on solid media. Further culture filtrates in different concentrations were added to the culture medium. The growth regulators presented in the agar caused knot formation on the shoots and on the leaves in both kinds of culture. There were significant differences in the cultural and physiological characters, auxin and cytokinin activity of the strains of different origin.Tétel Szabadon hozzáférhető Microsporogenesis of peach (Prunus persica L. Batsch) varieties(2002-10-16) Szalay, L.; Timon, B.; Szabó, Z.; Papp, J.Bud dormancy during winter is a critical factor in peach production in Hungary. The yield is determined basically by the survival rate of flower buds during winter frosts and by their ability to develop normal floral organs. It is important to investigate the genetic basis of slow floral development during dormancy for the purpose of breeding peach varieties with better winter hardiness. The aim of the present research was to examine microsporogenesis in 14 peach varieties during three successive winters in a Hungarian germplasm collection and to study the effectiveness of this method in variety evaluation. There were significant differences in the dynamics of microsporogenesis both between the varieties and between the years. Of the varieties, ‘Mayfire', bred in California, possessed the quickest pollen development rate. The microsporogenesis of `Piroska', a Hungarian local variety, was the slowest. Rapid floral bud development was observed in `Aranycsillag', `Springcrest' and 'Venus'. A medium developmental rate was characteristic of `Babygold 6', Fairlane', `Michelini' and `Red June', while development was slow in 'Champion', 'Early Redhaven', `Redhaven', `Harko' and `Mariska'. Based on these results, the study of microsporogenesis represents a reliable method for the phenological description of peach varieties during dormancy. The application of this method makes it possible to identify varieties and landraces with slow flower bud development, suggesting better winter hardiness.Tétel Szabadon hozzáférhető The new era of horticultural production after the millennium(2000-04-18) Balázs, S.; Kozma, P.; Nyéki, J.; Papp, J.The horticultural branches turn out, in relation to their area, a very great production . value. At the same time' many useful jobs are created. The development of gardening is, therefore, an important interest of our national economy. To the continuous enhancement of quality and quantity belongs the alloyage of new methods (biotechnology, integrated and organic procedures) with our traditional feats and with the incessant raise of the professional level.Tétel Szabadon hozzáférhető Perspectives and tasks in horticultural production(2002-04-15) Papp, J.; Nyéki, J.The work summarizes the prospective conceptions of all the five horticultural branches. These branches (vegetable, fruit, grape and wine, herb and ornamental plant production) with the production of propagating material together amount to round 30-35% of the total value of the entire plant production. The performance of horticultural branches declined significantly because of privatisation and lack of capital. The accession to the EU urges the development of modernization and competitiveness, therefore the state subsidies are indispensable.Tétel Szabadon hozzáférhető Reactions of different plant organs of pear cultivars to Erwinia amylovora infection(2003-04-14) Honty, K.; Boldog, Z.; Göndör, M.; Papp, J.; Kása, K.; Hevesi, M.Research project has been initiated in 1999 with the aim of evaluating the degree of susceptibility/resistance of pear cultivars grown in Hungary to fire blight disease caused by Erwinia amylovora. The recently selected promising cultivars were also examined. Inoculation experiments were conducted in controlled greenhouse conditions because of quarantine regulations in Hungary. Following the disease process, development of symptoms of plant organs (shoots, flower parts, fruits) was observed. Suspension of two E. amylovora strains (Ea 21, Ea 23) isolated from pear was used in a mixture (5x10 8 cells x m1 -1 ) for the inoculation. Twenty-six pear cultivars were examined and grouped into four categories: low susceptibility, moderately susceptible, susceptible and very susceptible. Most of the cultivars were susceptible or very susceptible while some promising 'Eldorado', 'Harrow Delight' and `Hosui' showed low susceptibility.Tétel Szabadon hozzáférhető Testing the virulence of some Hungarian Erwinia amylovora strains on in vitro cultured apple rootstocks(2000-08-23) Hevesi, M.; Papp, J.; Jámbor-Benczúr, E.; Kaszáné Csizmár, K.; Pozsgai, I.; Gazdag, Gy.; Balla, I.A useful method was improved to test and to evaluate the susceptibility of plants to fire blight and the virulence of E. amylovora strains. Six Hungarian strains from different host plants were tested on in vitro cultured apple rootstocks. Disease rating was used for the characterization of the process of disease development. The different strains had different capacity to cause disease, mainly in the first period of incubation. There were significant differences between the virulence of the strains.Tétel Szabadon hozzáférhető The tissue structure of the vegetative organs of strawberry (Fragaria moschata Duch®)(2000-02-23) Papp, J.; Lenkefi, I.; Gara, M.; Gracza, P.The tissue structure of the vegetative organs of strawberry (root, rhizome, stolon, leaf) is discussed in this paper. The authors stated that the root structure described by Muromcev (1969) and Naumann-Seip (1989) develops further from the primary structure. It grows secondarily and the transport tissue becomes continuous having ring shape. In the primary cortex of the rhizome periderm like tissue differentiates, but according to the examinations up to now, it does not take over the role of the exodermis. The exodermis is phloboran filled primary cortex tissue with 3-4 cell rows under the rhizodermis. The development of the transport tissue of the petiole is also a new recognition. In the lower third of the petiole the transport tissue consists of 3 collaterally compound vascular bundles. In the middle third there are 5 bundles because of the separation of the central bundle and in the upper third of the petiole 7 bundles can be observed because of the ramification of the outside bundles. Therefore attention must be taken also in the case of other plants at making sections. There might be confusions in the results of the examinations if the number of bundles increases in the petiole. The tissue structure might vary depending on the origin of the tissue segment. The palisade parenchyma of the leaf blade has two layers and it is wider than the spongy parenchyma. Among the 5-6-angular cells of the upper epidermis do not develop stomata while in the lower epidermis there are a fairly lot of them.