Vol 17, No 4-5 (2011)

Published December 4, 2011

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Articles

Organoleptic evaluation of sweet cherry varieties
7-13.

The extraordinary abundance of precipitation in 2010 (somewhere around 1000 mm) influenced highly the development of taste and flavour in cherry fruits. As stated, only a few varieties out of 27 were acceptable as for commercial quality. Under the given climatic conditions, actually ‘Bigarreau Burlat’ earned 965.11 points and proved to be t...he best in the early ripening group. In the mid season group, three varieties earned more than 1000 points (‘Giant Red’, ‘Carmen’ and ‘Vera’ grown at Nagykutas and Pallag), whereas in the late ripening group ‘Germesdorfi’ sent from Csenger (1084), ‘Linda’ (1070.07) and ‘Lapins’ (1052) received recognition. Correlation has been tested on the basis of 27 varieties between the individual properties. We sated that the most important attributes, which influenced the general impression of decision makers are the following: form and size of the fruit (r=0.835 and 0.797), furthermore juiciness (r=0.776), taste (r=0.876) and sweetness (0.875). Crispness was considered to be typical to cherry (r=0.743). Relation between acidity and sweetness was also essential to determine the acceptance of the cherry character.

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Effect of organic and integrated farming on carotenoid and tocopherol content of apricot fruits
15-18.

In 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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Preliminary evaluation of selected Prunus spinosa and P. insititia genotypes for their nutraceutical properties
19-22.

Fruits 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 ge...notypes. 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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Colour and water content detection of sweet cherry by portable spectrometer
23-26.

Based 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 experimen...t 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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Sensorial appraisal of sour cherries grown by environmental technology
27-30.

Sour cherry samples have been tested by a panel of potential consumers, and the judgments expressed by points given for each attribute. The correlation of individual traits with “general impression” has been explored. Primary raising of data was aimed to evaluate the effect of environmental growing technology upon sensorial impression of fr...uits for fresh consumption. Organoleptic tests consist of tasting and filling out of forms with numerical data as ratings them regarding taste, flavour and flesh firmness. The values of coefficients of correlation showed that a couple of other attributes as appearance, juiciness and sugar/acids perceived were irrelevant from the point of view of acceptance, i. e. the general impression.

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Effects of integrated and ecological growing technologies on the growth and development of fruiting structures in new apple plantations
31-33.

On the Horticultural Station of the Debrecen University, Pallag, two year old apple plantations of two varieties (‘Pinova’, ‘Golden Reinders’) have been studied, in autumn 2011. The growth of the cross section area of the trunk and the central axis were measured and compared to evaluate the effect of two alternative growing technologies...: integrated and/or ecological. ‘Pinova’ proved to grow more intensely than ‘Golden Reinders’ independently from the growing technology. The effect of the technology, however, was expressed in ‘Pinova’, where the integrated technology produced more vigorous growth than the ecological one. The effect of varieties on growing intensity was more distinct than the effect of growing technologies. Under the ecological growing system, the difference between the varieties studied is more accentuated regarding growing intensity. By that reason, in ecological growing plantations of varieties with moderate vigour ought to be stimulated by all possible techniques (as pruning, nutrition etc.).

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The effect of the intensity and method of pruning on the growth and yield of the apple variety ’Idared’ under conditions of ecological and integrated growing systems
35-39.

Summary: On the Experimental Farm of the Debrecen University at Pallag, a factorial experiment has been started at springtime of 2008 on an orchard of 12 year old apple trees ’Idared’ grafts on M 26 understocks. The first factor was the growing system (integrated versus ecological), the second was the intensity of pruning (strong versus mod...erate thinning of the crown), whereas the third was the method of pruning (shortening versus thinning of individual shoots). Measurements have been concentrated on shoot growth, flower initiation, fruit set and accumulated yield of two successive seasons. The following conclusions are made.
– In the ecological growing system, strong thinning proved to be beneficial for growth as well as for fruit bearing. – Strong thinning combined with shortening of shoots diminished yield in the first year, whereas
moderate thinning combined with shortening of shoots caused favourable growth and fruit bearing.
– In the ecological growing system, the moderate shoot growth was associated with better flower initiation, which increases the chances of alternate yielding.
– According to our results, the flower initiation of the ‘Idared’ was stimulated univocally by the thinning of shoots regardless of the intensity of pruning.
The right choice of the intensity and method of pruning is a decisive moment of a successful yield in the ecological apple growing system

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Summer pruning of sweet cherry trees and an inquiry of winter frost damages
41-44.

One of the most demanded research projects is the intensification of fruit production. The use of dwarfing stocks is a moderate solution as their effect is scarcely satisfactory. Climatic conditions of Hungary are continental in Eastern Europe, where Atlantic and Mediterranean effects are interacting with the continentals in a kind of basin wit...h characters of its own. Capricious meteorological episodes are often disturbing the security of development and fruiting of trees:
• winter frosts are damaging the cambium and fruiting structures of trees
• late spring frosts destroy cambium and flowers
• early autumn frosts hurt the leaves
• excessive precipitation impairs the growing fruits
• drought periods during the summer caused water stress disturbing water husbandry.

Vigorous stocks still prevail in the practice, and they ought to withstand challenges of weather hazards. The strong vigour of plants delaysthe process of senescence and the tendency of getting bald, and regeneration of plants is a sign of vitality. In present research, the trees have been trained on vigorous Prunus mahaleb stocks. Summer pruning was one of the important tools of intensive growing techniques. They were compared with traditional techniques and with plastic foil protected trees observing the vegetative as well as generative growth of them.

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Security of growing habits and bud formation of German sour cherry varieties
45-48.

Intensive sour cherry production is concerned to find the most productive varieties under special growing conditions. High planting density, adapted to manual picking or on the other hand to mechanical harvesting. Almost as important is the prolongation of the ripening season by enlarging the choice of varieties. Unfortunately, three of our fou...r leading commercial varieties are ripe almost at the same date.
Therefore, new varieties ought to be examined thoroughly. In the Pallag Experimental Station of the Debrecen University, five European varieties have been grown (’Schattenmorelle’, ’PI-SA 12,100’, ’Jade’, ’Gerema’, ’Achat’) and a Hungarian one, ’Debreceni bôtermô’ used as a check for the experiments to compare their growing and yielding habits in 2010. The plantation was three years old, standing on Prunus mahaleb rootstocks, in high density (5 x 2 m) and trained to slender spindle crowns. The results are proving that some of the varieties in
question are suitable to prolong the harvesting season. Growing habits and yields of the varieties related to the variety ’Debreceni bôtermô’ were similar or even better as ’Jade’, ’Gerema’ and ’Achat’. The ’Jade’ excelled with its vitality and ’Gerema’ with its generative character. Further studies are expected to prove the utility of
one of them at least to enlarge the ripening season on the fruit market.

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Evaluation study for the effect of four mango rootstocks on behaviour of Keit mango variety
49-53.

Our investigation was carried out in four mango rootstocks were namely Zebda, Socaria, 13/1 an 4/9. This study reviewed the effect of these rootstocks on growth behaviour of Keit mango variety as a scion grown on them. This evaluation and comparison included data on following aspects: the vegetative growth characters, root growth parameter, upt...ake of some macro nutrient and some organic substance. All results in this regard refer that the Socaria rootstock gave the highest values off all parameters so it is considered as a vigorous rootstocks, means that the trees on this rootstocks will reach to high size after short time. By contrast, Zebda rootstocks gave the lowest values in this concern and this will reflect on tree size on it. This means that the Zebda rootstocks will be useful in the system of high density orchard comparing with Socaria. Concerning to other rootstocks, they were intermediate between Socaria and Zebda rootstocks.

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Applicability of 3D laser scanning in precision horticulture
55-58.

Due to the technological development, remote sensing instruments and methods have become widespread in all segments of life (from precision agriculture through architecture to medicine). Among the innovative development of remote sensing instruments the 3D laser scanner is of outstanding importance. Horticultural applicability of terrestrial la...ser scanning technique is a new innovation in the precision agriculture. The structure of trees and branches, the canopy extension, the fruit yield, which can help to recognize some biophysical parameters, can be determined. The examination was carried out with Leica ScanStation C10 terrestrial laser scanner in the Study and Regional Research Farm of the University of Debrecen near Pallag. In this article the measuring principle, the parameters and horticulture applicability of the terrestrial laser scanner are presented.

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In vitro sensitivity of Monilinia laxa to fungicides approved in integrated and organic production systems
59-61.

The aim of this study was to test the in vitro sensitivity of two isolates of Monilinia laxa to fungicides approved in integrated and organic production systems. In vitro efficacy of 7 fungicides (Champion 50 WP, Kocide 2000, Nordox 75 WG, Olajos rézkén, Kumulus S, Rézkén, Rézoxiklorid) and another 6 fungicides (Score 25 EC, Efuzin 500 SC,... Systane, Folicur Solo, Zato Plusz, Rovral) approved in organic and integrated production systems, respectively, were tested against brown rot of sour cherry. The three isolates showed differences in sensitivity to fungicides. Fungicides (with active ingredients of copper and sulphur) applied in organic production showed relatively high percent growth capacity of M. laxa. Rézkén and Kocide 2000 showed the highest and Kumilus S the lowest efficacy against brown rot. Fungicides applied in integrated production showed relatively low percent growth capacity of M. laxa. Score 25 EC showed the lowest and Rovral and Folicur solso the highest efficacy against M. laxa.

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Incidence of postharvest decays on cultivars of pear, apricot, sour cherry and peach under two storage conditions
63-65.

In this two-year study, postharvest decays of pear, apricot, sour cherry and peach cultivars under two storage methods (TC and CA) were determined after four monthes storage periods; and then causal agents of postharvest decays of two pear cultvars were idenfified under traditional cold storage conditions. Results showed that postharvest decay ...was lower under controlled atmosphere compared to traditional cold one. Decay was lower on pear and the largest deacy occured on peach and apricot cultivars. Cultivars of fruit species also showed differences in incidence of fruit decays. Incidence of decays was independent on year effect. Under controlled atmosphere, postharvest decay ranged between 0 an 8% for pear, and between 5 and 12% for apricot, and between 6 and 11% for sour cherry, and between 5 and 15% for peach. Under traditional cold storage, postharvest decay ranged between 16 an 21% for pear, and between 15 and 39% for apricot, and between 10 and 22% for sour cherry, and between 19 and 33% for peach. Incidence of pear fruit damage ranged between 7.5 and 12.3%. Most damage started from injured fruit or wounded fruit. Five types of damage occurred ont he pear fruits in both years: Penicillium spp., Monilinia spp., Chondrostereum spp., other pathogens and mechanical injury. The most common damage was caused by Penicillium spp., Monilina spp. and Chondrostereum spp. On both pear cultivars in both years.

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Prevention and protection technologies – How do the growers get ready for climate change?
67-69.

Within the sector of fruit growing, climate change related tasks cover a rather wide range of activities. According to what is claimed by the literature, all decisions impacting the sector should be made conformably with climate change in order to advance an increase in yield security. This, regardless of the impacts of climate change, is also ...one of the key questions in fruit growing. Regarding protection against extreme weather events, in addition to technological and technical elements, the level of importance assumed by farmers for the abovementioned protection techniques as well as the type and extent they intend to use of this in practice are also worth of studying. This ongoing research beginning in 2009 mainly focuses on studying the opinions of fruit farmers making up the target group for this analysis. The questionnaire survey primarily intends to study their knowledge on the definition of climate change as reactivity to unfavourable weather events occurring in the growing. The study aims at providing a realistic view on the fruit-farmers’ knowledge on climate change and on how technological elements, new technical solutions applicable to mitigate damage are used during production.

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Possibilities and limits of use plastic constructions in fruit growing technologies
71-75.

On the Experimental Station Pallag of Debrecen University different combinations of fruit species and rootstocks have been raised under and without plastic foil cover in 2002. The growth and productivity of the grafts was our objective of comparison. Results revealed substantial differences in fruit set and yield depending on species and variet...ies. Sweet and sour cherry varieties grew much shorter under the plastic cover, whereas apricots, peaches and plums set fruit much more eagerly compared with the trees outside the plastic cover. Outside the plastic cover, the trees were much more developed at the beginning of their fruiting period. In spite of that, the growing processes were more intense under the foil. The differences are allegedly due to the repeated summer pruning necessary under the restricted space of the foil, on the other hand, due to the root concurrence because of the dense planting. Regarding the inner properties of the fruits, soluble solids, sugar and acids were higher outside, whereas macro- and mezzo-elements (P, K, Ca, Mg) were more abundant in fruits grown under the foil cover. Further efforts to explore those relations with other varieties and rootstocks are justified.

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Effect of hail protecting nets on the quality of apples
77-80.

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

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Effects of excessive weather on the micro-climate of apple plantations under the hail protection nets
81-85.

The general utilisation of hail nets is spreading all over the world and in Hungary too. Hail nets are at present the only tool, which
is able to prevent heavy hail damage in agricultural crops. Besides its numerous advantages, there are also deleterious side effects, e.g. it
changes the microclimate of the crop stand. Our study aimed to ...observe the differences, which characterise the physical status of crop stands
under the protection of hail nets compared with the stands in open air under various meteorological conditions: high or low temperature, calm
or windy atmosphere and their possible combinations. The results indicated that on hot and calm days the difference may attain 3–4° C. On
cool summer days, the difference was only 1.5 ºC. The hail net influences the relative humidity of the air, which means on ho summer days
often 7-8% differences. Conditions of radiation may also differ conspicuously. Measurements prove the reduced global radiation on sunny
summer days to 70%. This impairs as a rule the development of fruits reducing their quality and also its quantitative traits. Sunburn is, on the
other hand, significantly prevented by shadow.

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The tests of effectiveness of Frostbuster under excessive weather conditions in an apricot plantation
87-91.

Frostbuster is a new system, engine and technology, developed to protect fruit plantations from the frost damage. In order to raise domestic experiences and measurements, experimental approach has been initiated to prove the utility of the system under excessively low temperature in the plantation of the Siófoki Gyümölcstermesztési Zrt (Fru...it Growing Co. Siófok). The first opportunity ensued in the night of February 23-24, 2011, when the temperature sank to 12°C below zero. The question was to see whether we could prevent the drop of temperature by the frostbuster technique. The margin of an anticyclone staying on East Europe secured a stable condition to make tests. The only difference from the imaginable conditions of dangerous frosts was the heat keeping capacity of trees was weak, much inferior than compared with trees in full boom. As a consequence, the tree rows represented much lower heat-capacity and cooled down much quicker than blooming trees in springtime, i.e. their temperature was more variable. The other difference was, compared with an episode in spring that the hard frost lasted much longer than usually in spring. For testing the system, those conditions had even more advantage. Six meteorological stations helped us in measurement. Data-collectors were timed to 1 minute distances and the bulk of data proved to be beneficial for testing the Frostbuster. The results prove that the system is adequate to keep the temperature continuously higher than the surrounding field under excessively low temperatures. Further measurements are still needed to find the optimal solutions fitting to the growing site and its microclimate. Results presented offer a basis of further proofs.

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Effect of late spring frost event on nutrition aspects of a sour cherry orchard in East Hungary
93-97.

Similarly to 2007, 2011 was also critical year for fruit growers in Eastern-Hungary. Serious frost damage was observed at late blooming period (6 May (T=-1.6°C)) in this region, which caused approximately 60-65% of fruit loss. The aim of this study is to investigate the effects of a spring frost event on nutrient uptake and status of the ...trees of a sour cherry plantation at Újfehértó. The symptoms of frost were observed visually. This visual observation was confirmed by SPAD readings. The frost affected the macroand micronutrient contents of leaves. It was found that the frost affected the nutrient uptake negatively, but the effect of it was not significantly sometimes. It can be stated that the nutrient demand of trees can be supplied only under even worse conditions.

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Economic aspects of applying hail protection nets in apple plantations
99-101.

The up to date intense apple growing in Hungary is capable to produce yearly about 500-1000 thousand Ft/ha income, which means that the investment of 4 000–5 000 thousand Ft is returned by producing 10-20% net income. The economic balance may, however, be upset by the damage caused by hail, quantitative and qualitative, with an apparently inc...reasing frequency experienced in each third or fourth year. Estimates prove that each hail causing 50% damage may reduces the income proportionately to the capital by 1.5–2.0 percent points, which means a serious threat for the economy of apple production. According to calculations, a plantation producing 30–40 t/ha yields would not be able to raise incomes compensating the investment of 7.0–10.0 million Ft/ha, let alone the frequencies of hail damages. Consequently, 50–60 t/ha yields are needed to become successful, and in planning of new plantations those high yields are aimed with hail nets. An additional difficulty is represented by a lack of financial resources to install hail protection nets.

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Economic figures of apple production at national level of Hungary
103-105.

Apple is the most important fruit in Hungary, despite of that, it is a paradox that during the last years, apple growing was the most unsuccessful enterprise among the prosperous ones in the country. The real cause of regression was unequivocally the low price, which could be obtained and the inadequate structure of apple varieties. A heavy pro...blem is still the overweight of the quality doomed to supplying the processing industry instead to the fresh consumption. In order to improve the conditions, we aimed the economic analysis of the five year long period, 2005-2009, to trace the changes involving values and costs of production, income and all conditions combined with this activity. 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 that branch in economics.

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Economic figures of sour cherry production at national level of Hungary
107-109.

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.

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Economic figures of plum production at national level of Hungary
111-113.

In Hungary, natural conditions are optimal for growing plums. In spite of that, plum production was not a successful business in the past years. The reasons of it are, first of all, the utter fluctuation of yields and of the producer’s prices, increment of direct costs of production, dwindling incomes and uncertainties on the market. Serious ...problems are caused by the high rate of aged plantations, which are not counterbalanced by new plantings. Decisive is the “loose” ranging of the branch by the Union regarding plum production, which is expected for the sake of enlarging production and markets. Our aims are to analyse the management of the eight-year-long period, 2002-2009, and the fate of components of husbandry. The results presented are means of an utterly heterogeneous population of enterprises, being hardly suitable to make actual decisions, but they may enlighten upon challenges and recognise tendencies within the branch.

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The effect of drying process on the pigment content and composition of table beet varieties
115-117.

The food industry requires natural colouring agents in increasing quantities. Beet root is highly adapted to this purpose with its red (betacyanin) and yellow (betaxanthin) pigments suitable for numerous products. The two pigments are, however, very heat-sensitive depending not only on the method of drying as well. In our experiment we tested 6... table beet varieties with vacuum drying (instrument: Eurovac KIT-150) and obtained very big differences in the suitability of varieties for drying. The less colour loss was measured in Bordó (16.84%), while Rubin and Cylindra indicated 45.15 and 47.18% loss respectively. During the drying raw material with higher colour content produced higher rate of pigment loss (r = 0.880). In our experiment we found adverse effects on colour material and dry matter content in the fresh beet root. The variety with higher solids (mainly sugar) resulted in higher pigment loss (r = -0.847) during the vacuum drying process. Furthermore, we stated that the yellow pigments (betaxanthin) were less heat sensitive during drying than the red (betacyanin) ones. For the production of beet root powder varieties of high pigment content but low water soluble solids content (sugar) are needed.

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Increasing the vitamin D level of oyster mushrooms by UV light
119-123.

Vitamin D is essential for the human body and mushrooms are one of the natural sources of it. Many research works are aimed at enhancing the vitamin D2 content of mushrooms with UV irradiation in order to increase their vitamin D2 level, by transforming their natural ergosterol content into vitamin D2. The subjects of most of these studies are ...different kind of post-harvest cultivated mushrooms. In our experiment biologically active, pre-harvest oyster mushrooms were treated in the growing room with UVB and UVC light. UVB and UVC lamps (operating on 312 and 254 nm) and 6 time periods of irradiation (15, 30, 45, 60, 75 and 90 min) were used. After three consecutive days of treatments the yield were measured and samples were taken for vitamin D2 and ergosterol analysis. Data showed considerable increase (from 0,67 μg/g to 3,68 μg/g, f.w.) in vitamin D2 levels at every time period in case of both wavelengths.

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Tending operation models for white poplar (Populus alba L.) stands growing under sandy soil conditions
125-127.

Integrated research aimed to intensify the practices of afforestation especially of white poplar and grey poplar woods. A new, simplified tending procedure has been developed to substitute earlier models considering the target diameter by right spacing as a tool to achieve adequat quality of logs. The practice-oriented model may help the qualit...ative improvement of white poplar growing technology in Hungary as well as in Serbia.

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