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Study of genetic resources for Powdery mildew resistance by biochemical and physiological parameters on peaches and nectarines in Romania
57-61.Views:245During 1997-2002, studies on the physiological and biochemical changes due to powdery mildew attack in peach and nectarine cultivars and hybrids belonging to different classes of resistance had been performed at the Research Station for Fruit Tree Growing (RSFTG) Baneasa Bucharest, located in the southern part of Romania. The study was based on disease assessments in the field and on other diagnosis criteria.
The southern part of Romania has favourable ecological conditions for growing peach and nectarine but trees have been attacked by various pathogens such as Sphaerotheca pannosa (Wallr.: Fr.) Lev. var. persicae Woronichin fungus for a long time. The presence of the pathogen causes important changes in the quantity and quality of fruits and affects the metabolism of trees.
This study was focused on several physiological and biochemical parameters such as photosynthesis and respiration intensity along with catalase activity; and changes in some biochemical compounds such as free, total and linked water content, dry matter, nitrogen and protein content, tannin levels. The aim was to find possible correlation among the above parameters and the biotic stress induced by the powdery mildew fungus calculated as attack degree (AD%).
Results showed that photosynthesis diminished significantly in the case of the attacked phenotypes, the respiration was more intense in the infected cultivars and catalase proved to be less intense in the affected plants. The total water content significantly increased in contrast to the dry matter and tannin contents, which greatly reduced in the case of resistant cultivars such as 'Victoria', Vectared 7', 'KB 11-40'. The total nitrogen and protein levels showed less influence on resistance to powdery mildew on all cultivars. All genetic material found resistant to powdery mildew is currently used in peach and nectarine breeding programs in Romania.
Further studies focused on isolation and characterization of resistance genes for powdery mildew resistance will be done in the future based on data collected during several years.
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Investigation of the Relationship between the SO2 Production of Different Yeast Strains and Thiamine Concentration
57-62.Views:302Our general conclusion was that the thiamine amounts of 0,6 and 3,0 mg/1 added prior to wine fermentation, resulted in higher free-S02 level in comparison to the control. Furthermore, among the yeast strains examined in our experiments, Uvaferm BC strain produced the highest free-S02 content under the conditions mentioned before. As regards the dynamics of reductone and SO, production, the concentration of the previous one was practically identical in the middle and at the end of the fermentation while the SO2 content — both free- and total — was lower at the end. Thiamine addition did not cause any difference in the organoleptic properties of wines as proved by sensory analysis.
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Consumer preference for apples: the role of attributes influencing the choice and consumption
37-43.Views:1068Consumers consider good quality fruits to be those that look good, are firm and offer good flavour and nutritive value. Nowadays, consumers are, however, increasingly interested in food qualities which cannot be discovered by looking, tasting or smelling the products but their roles are not yet really cleared up. Therefore the objective of this study was to explore the importance of selected kinds of attributes (taste, size, colour, cultivar, origin and price) in fluencing the choice of apples of customers. In accordance with several authors, fruit qualities (taste, size and colour) seemed to be the major attributics influencing the choice of apple independently of people's age and gender. However, the size of fruit had lower importance with increased age. Generally, females gave higher importance rating for most attributes than did male. The price was getting more important for consumer's choice with age which can be connected with their socioeconomic situation. The origin of fruit and the cultivar did not have important influence on consumer's choice. Authors also investigated the preference of consumers for six selected apple varieties ('Jonagold', 'ldared', 'Royal Gala', 'Golden Reinders', 'Braeburn' and 'Granny Smith'). and pointed out the role of the origin in fruit quality and in choice of apple in the case of 'Granny Smith' cultivar. Apple fruit samples from Austria, Argentina, Chile, Hungary and South Africa were involved in this study. Authors evaluated fruit quality parameters of above cultivars and compared them to consumer preference. Consumer preference usually represented the quality attributes of the fruit well. It is also concluded that degree of liking of apple cultivars varies through gender and age. Children and young consumers preferred 'Royal Gala', 'Granny Smith and 'Braeburn' mostly. In spite of 'Idared' is one of the cultivars grown on the largest area in Hungary, the lowest preference ratings were given for it in both gender categories. Middle-aged consumers (between 25 and 50 years or age) preferred crispy apples with red or blemished skin color ('Royal Gala' and 'Jonagold'). 'Jonagold' and 'Idared' were the most preferred cultivars for the consumers above the age of 50 likely because of their relatively low price, as price plays a significant influencing role in the purchase of these consumers. The relatively expensive and soury 'Granny Smith' appeared not really preferred by this age group. In spite of the significant differences in instrumentally measured fruit quality parameters among 'Granny Smith' fruit samples from different countries, consumers did not give significantly different preference rating scores for those.
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Branching features of apple cultivars in integrated and organic production technology
11-14.Views:620In our study, vegetative characteristics of 39 apple cultivars were evaluated in environmentally friendly production systems. Numbers of the branches of the central leader in different high zones were shown. According to our results, number of the branches of the axis was probably larger in the integrated production system, compared to the organic one, which is related to the conditional status of the trees. Based on our experiences training and maintaining canopies in integrated system was easier, as relative more extensive canopies were needed in organic farming.
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Agronomic evaluation of different lettuce (Lactuca sativa L.) varieties under unheated plastic tunnel
50-56.Views:593Among the leafy vegetables, lettuce (Lactuca sativa L.) is the most widely grown species in the world. Wide ranges of physical properties of the products are used to assess the degree of maturity. In this study, different lettuce varieties were grown under an unheated plastic tunnel in springtime. We evaluated the agronomic properties of different lettuce varieties, evaluated the condition of the plants, and determined the bioactive substances. Larger head weight can be achieved by the ‘King of May’ butterhead (259.31 g) and ‘Great Lakes 659’crisphead (220.40 g) genotypes. A very strong correlation (r = 0.995) was observed between the lettuce head index, and leaf index and both had a strong positive correlation (r = 0.828 and 0.760) with NDVI. The highest SPAD values were measured for cos lettuce ‘Romaine lettuce’ (44.01) and iceberg lettuce ‘Great Lakes 659’ (42.71). However, these genotypes showed the highest (9.52%; 8.74%) dry matter content, too. The red leaf variety 'Lollo Rosso' had the highest total polyphenol content (181.53 GAE/100 g FW). Among the evaluated properties, iceberg lettuce showed favorable morphology, plant condition, and good dry matter content. In addition, between the loose-leaf lettuces, the red leaf lollo type was outstanding with bioactive content.
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The Hungarian peach production risks
85-89.Views:319Hungary possesses very good agroecological conditions even in a European comparison. Agriculture and food production is highly important despite its decreasing relative economic significance, since providing high quality and affordable food for the population is a basic social necessity and one of the decisive factors in quality of life. The development of vegetable and fruit production is of great importance both from a healthy nutrition as well as from a comparative advantage (cheap labour, expertise, production traditions, favourable climate) point of view.Vegetable and fruit consumption per capita is lower than in developed countries, which is a decisive indicator of healthy nutrition, but improvement is continuous and desired. Appropriate quality and quantity in production is a requirement to meet customers’ needs in a highly competitive market from one year to the next. Hungary can only be competitive if production results are improved while risks are reduced. Fruit production is a sector with high capital requirements, risk assessment is very important from a production, investment as well as from a national economy point of view. Our examinations will focus on production risk, which is present in the annual fluctuation of average yields, especially as a result of extreme weather factors.
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Results in the determination of some Hosta varieties by the method of isoelectric focusing
90-92.Views:363Mass propagation of 5 newly introduced Hosta varieties was carried out by the method of micropropagation. Our aim was to determine exact variety specificity after the micropropagation period in the pattern of peroxidase isoenzymes by isoelectric focusing in pH 3-9 range and to determine that phenological phase of mother plant in which the isoenzyme pattern of mother plant can safely be comparable to the isoenzyme pattern of micropropagated descendants. The isoenzyme patterns of descendants were similar to the mother plants of the same hybrid lines. The older leaves seemed to be not so suitable for examination than newly developed ones despite of the higher activity of peroxidase enzymes. There were big differences in isoenzyme patterns of leaves in different phenological phases. With this quick and easy method Hosta varieties could be selected already in the very early stage of micropropagation.
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Foliar application of zinc and its effect on greenhouse grown cucumber
79-82.Views:544The experiment was conducted to examine the effect of the foliar application of zinc on yield and crop quality and on fruit mineral composition of cucumber plants (Cucumis sativus cv. Mustang) which were grown in peat in containers under unheated conditions and were not showing visible signs of zinc deficiency.
In the trial the following 3 treatments were set up in 4 replications: Znl = 0.35 g/litre Zn, as foliar fertilizer; Zn2 = 0.7 g/litre Zn, as foliar fertilizer, control = no foliar fertilization. Foliar fertilization was applied 5 times with 10 day intervals. After their planting out the plants were fertigated daily with water soluble complex fertilisers. Fruits were harvested twice a week, 16 times in all, and were divided into three quality classes (class I, class II and substandard). Shoot length of the plants (plant height) was measured on 3 occasions. Zinc content of the fruits and leaves was analysed at two times.
From the results of the trials it can be concluded that the 0.35 g/litre Zn (0.35 mg/ml) foliar fertilisation had beneficial effect on cucumber both in terms of yield and quality. Under the conditions of the experiment (daily fertigation through drip irrigation) the effect of a more concentrated foliar application of zinc seemed less beneficial.
The zinc content of the fruits showed no evident increase in response to foliar fertilization, while a significant increase was seen in the leaves, particularly with the more concentrated Zn treatment. This indicates that in the case of cucumber zinc, through its assimilation in vegetative parts, has an indirect effect on fruit development.
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Colour and water content detection of sweet cherry by portable spectrometer
23-26.Views:35467Based on the most recent data, the average amount of sweet cherry produced in Hungary is around 10-12 thousand tons. Therefore fast and effective method is important for sweet cherry fruit quality analyses. The aim of the study was to examine the applicability of reflectance measurements for sweet cherry fruit quality analyses. In our experiment five cherry species (Vera, Cristalina, Germersdorfi, Noir de Mechet, Canada Giant) were examined in order to measure the spectral differences between species. Further more, spectral alteration was examined between different health and maturity status of the fruits in the case of a specified, the Germesdorfi species. The four new indices are appropriate tools for cherry quality analysis. Thus reflectance measurements can also support more precise and automated fruit selections. The methods for the differentiation of species could also be viable at a concerned habitat; however, the climate, habitat and soil conditions strongly affect the yield quality. Concerning the fast determination of water content, WBI could be a reliable method for the assessment
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Obtention of new ornamental leaf variants of giant reed (Arundo donax L.) originated from somatic embryogenesis and their photosynthetic parameters
18-24.Views:1046Giant reed (Arundo donax L.) is a perennial rhizomatous herbaceous plant, it has been widespread all over the world by human activities. It is a 2-8 meter high, polyploid, sterile species (not produce viable seeds), it can be propagated only by vegetative methods (rhizomes, stem cuttings, in vitro biotechnological methods). It has considered promising dedicated energy crop thanks to high biomass production (20-40 dry tons per hectare depending on microclimate), adaptability of different kind of soils and environment and low energy input required for its cultivation. It has been utilized for energetic purposes, biogas/bioethanol production, cellulose/paper production and ornamental purposes. The objectives of the present study were to determine morphological properties of new ornamental giant reed leaf variants originated from somatic embryogenesis and to evaluate their photosynthetic pigment content and photosynthetic activities. The most typical changes was the appearance of different colour (white, yellow, light green) longitudinal stripes on leaves (also on petiole and on leaf blade). It was significant differences (p<0.05) between green and leaf variants in case of photosynthetic pigments content and photosynthetic activity (Fv/Fm value). There was no detectable chlorophyll a or b content in the white bands of leaves and albino shoots. Total chlorophyll content of the white striped leaf variety was more than twice than the light green leaves. Photosynthetic activity and content of photosynthetic pigments also confirm and determine the morphological characteristics and growth habit of leaf variants.
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Investment analysis of Hungarian apple-orchard and fruit storage projects
157-162.Views:598There are profound, long-term changes in world apple production and trade. The former hegemony of Europe in apple production doest not exists any more, among the most important apple exporters the emerging economies have a growing importance. The globalising apple market means new challenges of traditional producers. This is especially true for Hungary, which has been the most important apple exporter in terms of quantity thirty years ago, but now its production hardly covers the domestic demand. A necessary precondition of the modernisation is the re-construction of plantations and the cold-storage system. Analysing the economic effi ciency of apple production and cold storage, it is obvious, that a necessary precondition for the modern, competitive apple production is the availability of cold-storage facilities. Neither the apple-production, nor the cold-storage can not evaluated separately from each other. Under current Hungarian conditions there is a need for active state support for the establishment of cold-storage facilities.
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Fruit coloration of apple cultivars
11-14.Views:646One of the most important parameter of apple cultivars is the scale and the intensity of the coloration of fruits. Nowadays among the bicolour cultivars those are the most saleable which have the highest and darkest fruit coloration. In our three years old study cultivars born with bud mutation and cross breading were examined, which have superior coloration peculiarities than their parental cultivars. According to our results among the observed cultivars the cvs. ’Gala Decarli-Fendeca’, ’Galaval’, ’Wilton’s Red Jonaprince’, ’Early Red One’ and ’Red Cap Valtod’ reached favourable high fruit surface colour (80-100%) regardless the vintage effect. Concerning the colour intensity, that is the darkness of the red colour most of the cultivars (‘Gala Venus Fengal’, ‘Gala Fendeca-Fendeca’, ‘Galaval’, ‘Jeromine’, ‘Red Topaz’, ‘Early Red One’, ‘Crimson Crisp’, ‘Wilton’s Red Jonaprince’) showed excellent values (4,5-5,0). Based on the fruit surface colour and the fruit colour intensity a new index number, the fruit coloration index was created by us, which describes the coloration features in a complex way.
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Determination of biogenic amine - content of natural wines
91-95.Views:366Nowadays the consumption of natural wines has been increased. In parallel with the higher demand, the study of the parameters of natural wines has also developed. The amines being produced during the decarboxylization procedure of amino acids could be one of the most important features of natural wines. The objective of this study was to measure the biogenic amine content of natural wines from 2000 and 2001. We have determined that the biogenic amine content of natural wines is not different from the biogenic amine composition of normal wines. There was not any considerable difference between the years. In complience with the average tendency, red wines contain higher histamine-, tiramine- and serotonin values than white wines.
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Agroclimatological properties of growing sites assigned to apple and pear production in Hungary
95-97.Views:844Apple and pear growing sites in Hungary are classified into four regions according to the Hydro-thermic Coefficient: dry, moderately dry. moderately humid and humid. Most of the plantations of apple and pear are located in regions considered as moderately dry and moderately humid. Within that category, the two respective species have different preferences, i.e. the ecological features of Hungary give different opportunities for apple and pear growing. Apple is grown almost everywhere in the country, successfully. The selection of cultivar-regions is needed mainly for increasing competitiveness on the market. Main apple growing regions are listed in 3 large groups. For the definition of cultivar-regions, mainly the configurations of soil and precipitation, i.e. conditions of the soil and opportunities of gaining water were decisive. Market factors are also considered. The area assigned to pear is much less than that of apple, in Hungary. Some well known and popular varieties would require high air humidity which cannot be presented in most of Hungary. Therefore, the possibility to establish regions for pear varieties is restricted, we have to create a particular micro-environment. Two groups are potential. The first one comprises sites where the annual precipitation is 700 mm, at least. There, apple and pear production would compete each other. In more dry habitats (less than 700 mm annual precipitation), micro-environments should be found and only drought-resistant, mainly summer-ripe cultivars should be chosen with, preferably, low tendency of sclereid formation. In that case, neither irrigation could help to produce adequate quality in varieties sensitive to low air humidity.
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Preliminary evaluation of selected Prunus spinosa and P. insititia genotypes for their nutraceutical properties
19-22.Views:1131Fruits of nine Prunus spinosa and P. insititia selections were compared in their ferric reducing antioxidant power and total phenolic content. The antioxidant capacity and total phenolic content ranged between 6.36 and 29.26 mmol AA/L, and 5.04 and 29.71 mmol GA/L, respectively. These ranges cover an almost 5-times variation among the tested genotypes. The Pearson’s coefficient was very high (0.92) indicating a major contribution of polyphenolics to the antioxidant capacity of the tested Prunus fruits. Conserving resulted in an approximate 20 % loss of antioxidant power and slightly increased phenolic contents. Our results led us to the conclusion that fruit of Prunus spinosa and P. insititia might be considered as rich sources of antioxidants. In addition, procession with heat treatment caused only a slight decrease in the antioxidant capacity without loss in the total polyphenolic content.
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Evaluation of morphological parameters and bioactive compounds in different varieties of beetroot (Beta vulgaris L. ssp. esculenta GURKE var. rubra L.)
31-35.Views:804Beetroot consumption based on pickled beets generally in Hungary which is due to the higher yield from second crop harvested in autumn and processed by manufacturing industry. Researches of the past years confirmed its favourable nutritional-physiological effects on human body so demands, as for fresh salad, also increased. The trial aimed at testing the interaction of varieties on quality parameters and in the same time suggestions are made how to use different varieties of beetroot according to its quality. Morphological and sensory evaluations were examined on 10 varieties of beetroot harvested in autumn. The regular spherical shape can reduce the refining loss during the processing of beetroot which is beneficial for the manufacturing industry. In our trial the root shape of Libero, Mona Lisa and Rubin varieties approached most the regular spherical shape (diameter/length – 1.0) which is favoured by not only processing industry but also fresh market. The highest red pigment content (betanin) was observed in Mona Lisa, Akela and Cylindra (34.58–47.66 mg/100 g). A similar trend could be observed in yellow pigments (vulgaxanthins) which proves the close correlation between the quantities of the two pigments (r=0.898). Highest total polyphenol (77.13–83.37 mg GAE/100g) and flavonoid (21.73–22.73 mg CE/100g) contents were detected in Akela, Mona Lisa and Bonel. These varieties are favourable for fresh salad and they can satisfy processing requirements also. Highest water soluble solids content was found in Akela (7.15%). In our conditions nitrate (NO3-N) values below 900 mg/kg were examined in all of the varieties which is favourable in the case of beetroot.
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Plant of interest — Prunella vulgaris L.
73-77.Views:440Self-heal (Prunella vulgaris L.), known as a remedy traditionally used as Chinese medicine, was neglected in modern pharmacy until the 20th century. Although in the Middle Ages it was respected for its wound-healing effect, the usage of this medicinal plant was confined just to the conventional pharmacy. Nowadays, because of the great dislike of synthetic materials, however, self-heal has become one of the most important target plants again. Owing to its valuable active constituents, besides its wound-healing effect, the plant can also be used as hepato-protective, antioxidant, anti-HIV, anti-cancer remedy, and it is effective against Herpes virus, as well. Its taste — and odourless extracts are applied by the food industry as natural food preservatives. Taking into account the importance of self-heal our aim was to introduce this plant species more detailed with regard to its active agents, effects and cultivation methods.
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In vitro investigation of King Oyster Mushroom [Pleurotus eryngii (DC.: Fr.) Quel.] strains in vegetative growing phases
47-53.Views:370The king oyster mushroom ( Pleurotus eryngii) is more and more popular amongst the producers due to its excellent taste and relatively easy cultivation . In the course of our work we collected 15 king oyster mushroom strains from various habitats in Hungary in order to get a better picture about the growth of the vegetative mycelia of the species and its different strains. In the in vitro experiments we investigated the growth of the strains at various temperatures and pH. incubated them in light and darkness and in aerobic and anaerobic atmosphere. In addition to these we measured the weight of dry mycelia produced in a given time by the strains. Our results showed that the above mentioned environmental conditions resulted in a very different growth rate of the vegetative mycelia of the various P. eryngii strains. These results may provide valuable data about the vegetative phase of the cultivation.
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Effect of organic and integrated farming on carotenoid and tocopherol content of apricot fruits
15-18.Views:909In modern and healthy diets antioxidants play an important role providing natural defence against serious diseases. Therefore it is recommended to include fruits and vegetables having high antioxidant capacity in daily diet in a due course. Apricot is one of the fruits receiving an increasing attention in this field. This study was conducted to investigate the composition and content of fat-soluble carotenoids and tocopherols in different varieties of apricot using recently developed liquid chromatographic methods. Also it was aimed to compare organic and integrated farming in their effect on carotenoid and tocopherol content of the fruits. The results showed that apricot fruit are rich in vital carotenoids and bioactive tocopherols with significant variation between different varieties. The organic farming had favourable effect on the level of the major carotenoids and depending on variety this technology either increases or does not have significant influence on vitamin E content.
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Selection of the chance seedlings of `Mézes körte' (Pyrus communis L.) from the gene bank of Keszthely
21-27.Views:719We have concluded the selection tests of the `Mézes körte' seedlings planted in the spring of 2006, with special emphasis on the cotyledonary, foliage leaf and the height of plant. Out of the 75 seeds planted in rows, there were 40-45 pieces growing out, so during the first cotyledonary test we had to calculate with almost 40% decay. On 12th April 2006, we recorded some of the important characteristics of the seedlings in their cotyledonary stage which characteristics were important from the point of view of selection (cotyledonary form, cotyledonary length, cotyledonary thickness, cotyledonary colour, cotyledonary petiole length, cotyledonary petiole thickness, cotyledonary petiole colour). The above morphological characteristics are shown in Table No. 1-6. We have also tested the seedling in foliage leaf state, paying special attention on the development stage of the plants (colour of foliage leaf , height of plant). We have completed statistical calculations of the two above mentioned characteristics. The result of that is summarised in Table No. 8-9. The variation coefficient show smaller value in the case of the foliage leaf number (15-32%), while the wider range of spread of the data referring to the height of the plant is shown by the 33-61% CV values. On charts No 4-9. we present the relationship between the height of the plant and the number of foliage leaf, as well as the differences between the two graphs. Based on the above charts and graphs it can be defined that the 40% destruction of the developing seedlings during the period till the next measurement reached 70-80% level. In spite of this however some seedlings showed strong and balanced growth (A44, B42, C25, D16, E5, E39, F38), the further testing and selection of those is to be completed in the future.
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The Role of Human Factor in the Innovation of Apricot Production-Empirical Study in a Disadvantage Area of East-Central European Country
131-134.Views:1152Hungary is a traditional fruit growing country for ages. As fruit sector has a very high hand work request and value added, it has an important role to decrease the elimination of unemployment and the lack of income in the disadvantage rural areas. The study was made in the year of 2009, the studied population consisted of the members of the fruit-grower marketing organization (Gyümölcsért Ltd.), that organizes growing and sales of stone fruits in Hungary. The number of studied population were 95 capita, the number of fi lled out and evaluated questionnaires was 35. By the composition of the questions both qualitative and quantitative methods have been used. We tried to get answers to the following questions: Are the studied human factors (age, educational level, sex etc.) of growers, determined the extension of innovation of apricot production?
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The effects of growth regulators in proliferation of Sorbus redliana 'Burokvölgy'
77-83.Views:364The Hungarian cultivar Sorbus redliana 'Burokvölgy' was proliferated on Murashige and Skoog (MS, 1962) medium with half-strength macroelements and 100 mg/1 meso-inositol, 20 g/1 sucrose, 11 g/1 agar-agar. Different combinations of kinetin (KIN), metatopolin (mT), benzyladenine (BA), benzyladenine-ribosid (BAR) and indolebutiric acid (IBA) were tested, and pH was adjusted to 5.6 every case using KOH. The cultures were incubated at 20-24 °C in 8/16 hours dark/light photoperiod for 50-52 days. The main aim of our research was to find the optimal growth regulator and its optimum concentration. Purthermore, to determine the chlorophyll contents of the in vitro propagated plants' leaves. During the proliferation, the highest number of shoots were observed in the case of using BA + IBA, and on the medium containing 0.75 mg/I BA + 0.05 mg/1 IBA 8.93 shoots were found. The addition of KIN + IBA decreased the number of shoots and increased the sizes of leaves — the widest (11.2 mm) and longest (17.8 mm) leaves were obtained on the medium containing 1.00 mg/I KIN + 0.05 mg/1 IBA. The longest shoots (36.46 mm) were found in the case of applying 0.75 mg/1 BAR + 0.05 mg/I IBA. The BA + KIN + IBA combination resulted the shortest shoots. Sometimes not only shoot regeneration but spontaneous rooting was observed during the multiplication. The highest chlorophyll content (1.569 mg/g total chlorophyll, 1.132 mg/g chlorophyll-a, 0.437 mg/g chlorophyll-b) was obtained in the presence of 1.0 mg/I KIN + 0.05 mg/1 IBA.
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Study on the yeast and mould biota of the botrytized grapes in Tokaj region in two years
61-65.Views:287The famous wine Tokaji Aszú is produced from "noble rotted" grapes infected and modified by Botrytis cinerea under special condition. The objective of this study was quantitative and qualitative characterisation of saprophytic fungi present on the surface of aszúberries, with special regard to yeasts. There were considerable differences in these populations depending on the origin of noble rotted berries, notably between berries taken from the vine or the ones taken from the winery. Beside Botrytis, other mould species like Penicillium, Aspergillus were commonly found, in widely varying population. Yeast counts were detected between 104 and 107 cfu/g berry. In the samples taken from the vineyard Candida pulcherrima predominated followed by some aerobic basidiomycetous species, but Hanseniaspora species were also present in relatively high population. After transport and storage of the grape in the wineries, population of aerobic yeasts and C. pulcherrima quickly declined and Candida stellata followed by other sugar tolerant species became dominant. This autoselection process directs attention to the importance of storage conditions.
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Maceration affects mineral composition and pH of wines
25-29.Views:472Mineral composition of wines is affected by many ecological and technological factors. These variables are mostly discussed focusing on certification of origin and human health. This paper gives data on possible changes in mineral composition and pH of wines due to 4 hours skin maceration (1st trial) and fermentation sur marc (2nd trial). Experimental site is situated on acidic sandy soil in middle east Hungary. The variety collection was established in 2003 with own rooted planting material in 3x1 m spacing, trained for single curtain training
system. Mineral composition of wines was determined with ThermoFischer Scientific iCAP 6300 ICP-OES, pH was measured with pH10pen (VWR International) in field, and with SevenEasyTM pH meter (Mettler Toledo) in laboratory. 1st trial with 9 PIWI white wine grape varieties pointed to demonstrate effects of skin maceration, which is abundantly used to elevate aroma content. 2nd trial with the use of ‘Medina’ red PIWI grape variety aimed to demonstrate effects of double pasta skin maceration in rose and red wine technology. Data of 1st trial show, that K, Cu, Mn and P respective increase with skin maceration, despite Fe show considerable decrease. Data of 2nd trial show, that K, Mg, Mn, P, Sr and B increase with longer skin contact and higher fermentation temperature, despite Fe and Ba decrease with this technology. In regard to pH, data show, that skin maceration and fermentation sur marc increase K content with about 30-70% respectively, withstanding that pH also increase with a considerable 0,4-0,5 value. K content can be higher in the end product, despite to earlier higher level of tartrate formation. An attention should be driven to lower level of tartaric acid and consequently higher pH characteristic for wines produced with the application of skin maceration or fermentation sur marc. -
Analysis of the polyphenolic composition of red wines with particular respect to the resveratrol concentration
17-22.Views:354In our work we have studied red wines of some vine-districts. In the centre of interest was resveratrol. We declared, there was not significant difference between varietys in polyphenol comparison. There was significant variety in anthocyanin and colour-intensity.
