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Evaluation of fruit quality parameters of Rosa taxa from the Carpathian basin
81-87.Views:172From the wide range of genetic sources available in Hungary, we have chosen as objective the evaluation of those rose taxa, which — on the base of their quality and morphologic features — are suitable for selecting fruit production varieties or parent varieties for further breeding. We examined physical and inner parameters of fruits of Rosa taxa, and evaluated the correlations by mathematical statistic methods. Namely, if a correlation can be found between physical and inner parameters, fruit production value can be determined by less examinations in the future. According to our results, there is a large variability in some physical parameters (weight, diameter of fruits; weight, number of achenes) as well as in inner content values (vitamin C, glucose, fructose, K, Ca, Fe, Zn and Cu content) of rosehip, regarding production year, habitat and even the individual of examination. Twice as much ascorbic acid can be found in achene-free fruits, and nearly five times as much in their dry product as in fresh whole fruits. It was established repeatedly, that vitamin C concentrates in fruit flesh, and ascorbic acid content can be preserved better in achene-free flesh. There is no essential difference in citric acid and carbo-hydrate content of whole and achene-free rosehips. However, macro- and microelement content of whole fruits is 30-40% higher than that of achene-free fruit flesh. The connection between fresh weight and diameter, as well as achene number and seed weight of fruits can be described by the function y=axb. A significant relationship can be found in case of K-Fe, Ca-Mg, Ca-B, Ca-Mn and Zn-Cu, between fresh weight and B content of fruits. According to our examinations, fresh weight of rose species with a higher citric acid content is usually higher, while their Fe content is smaller. Glucose content of fruits of rose species is directly proportional to their Ca and Zn contents. Zn content of rose species with higher fructose content is usually smaller.
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Assessment of apple varieties based on consumer judgement in integrated production for fresh consumption
71-74.Views:240In a former paper we treated the same relation comparing varieties frown in the biological or organic system of growing, now the tests have been performed with samples grown by the integrated system. The scores registered properties as taste, skin, colour, consistency and size. In addition, we also explored the relation between general impression and the individual properties.As first purpose, we started with collecting primary data on 15 samples taken from fruits grown by the integrated method and kept over 60–90 days in a store, then offered to the consumers. The test is based on an organoleptic assessment (records are registered in a questionary). The individual judgements are processed and coefficients of correlation between the traits (taste, skin, size, colour) calculated. The validity of the mathematically proved relations is considered to be decisive in judging the preferencial consumption of fruits.
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Antioxidant activity of medicinal plants used in phytotherapy
28-35.Views:252Oxygen free radicals play an important role in the development of different disorders like inflammatory-immune injury, carcinogenesis, hepatic toxicity and artherosclerosis. The antioxydant role of a wide spectrum of natural products has been established. Flavonoids and other phenolic compounds (proanthocyanidins, rosmarinic acid, hydroxicinnamic derivatives, catechines, etc.) of plant origin have been reported as scavengers and inhibitors of lipid peroxidation.
We have studied the antioxidant activity as well as content and composition of natural phenolics in a series of medicinal plants with phytotherapeutical significance. Thus we determined the total phenol contents and studied the composition of flavonoids, polyphenols, phenolic acids of different vegetative and reproductive organs of medicinal plants: Anthriscus cerefolium (L.) Hoffm., Petroselinum crispum L., Cichorium intybus L., Helichrysum arenarium D.C.„cempervivum tectorum L., Taravacum officinale Web.
Characteristic constituents in the various crude drugs were determined by chromatographic (TLC, HPLC) and spectroscopic (UV, UV-VIS) methods. The non specific scavenger activities of the medicinal plant extracts were studied by the chemiluminometric technique. The changes of chemiluminescence intensity of the H,G,•0H-luminol system at increasing concentrations of the H702/ -OH were measured. Inhibitory effects of selected standardized fractions from plants were tested on ascorbic acid induced lipid peroxidation in rat liver and homogenates.
The best correlation were established with total phenolics in some medicinal plants (S. tectorum, T. officinale) while activities in other cases seem to be influenced by flavonoids (P. crispum, H. arenarium, A. cerefolium) and by hydroxicinnamic derivatives (C. intybus).
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Comparative study of three rosemary (Rosmarinus officinalis L.) clones during the growing season
67-72.Views:197The growth rate of three rosemary clones, `Harmat', 'Salem' and `Horvát', their essential oil content and its components as well as the total phenol content and total antioxidant capacity in their aqueous and ethanolic extracts were compaired. Total phenol content (determined by Folin-Ciocalteau reagent) and antioxidant power (FRAP-value) of aqueous and ethanolic rosemary extracts were measured by spectrophotometric method. The essential oil content was determined from drug by water-steam distillation. `Harmat' showed the most intensive growth through the vegetation period. The total antioxidant power of the ethanolic extracts from all the three clones was similar: a decrease was observed at the end of the season. In most cases more antioxidant compounds were dissolved in the aqueous extracts. The total quantity of phenolic compounds shows a good correlation with the potential extent of stress effects. The difference among the phenol contents of the various clones can be derived from the difference in their tolerance, because phenols have antioxidant effects contributing to protection against harmful impacts. Difference between the two extraction methods (aqueous and ethanolic) is due to the distinct solubility of compounds. Some other components, like essential oil compounds also possess antioxidant effect and in this way they may influence the antioxidant power of extracts.
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Evaluation of different sources of resistance for breeding powdery mildew resistant grapevine varieties
35-40.Views:188The appearance of resistance to powdery mildew was investigated on seedling progenies of interspecific crossings. Hybrids of American and East-Asian wild species and one Vitis vinifera variety (Janjal kara) were used as source of resistance in the crossings. The resistance of foliage and of berries were tested in the field at the time of vintage. The degree of resistance was ranked into six classes.
In American and Asian hybrid derivatives there were few highly resistant progenies, but in the hybrids of Janjal kara variety more than 90 % of the progenies proved to be highly resistant to powdery mildew. According to the distribution of classes of resistance in the populations the resistance of American and Asian sources are mostly influenced by additive gene affects. The resistance of Janjal kara seemed to be mono or digenic.
No close correlation was found between the powdery mildew resistance of the foliage and that of the berries.
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Assessment of soil characteristics in orchard
11-14.Views:230The research field was at Siófok, in Hungary, which is situated in the South East side of Lake Balaton. The physical characteristic of the soil is sandy loam and loam and the peach orchard is irrigated. The detailed goals were mapping and analyzing of physical properties of the soil in water management point of view, mapping the acidity and CaCO3content of soil for precision liming, measurement of humus the element content. Sites with different physical characteristics (from sandy loam to loamy clay) could be distinguished. The reason for this is that besides the possible increase of clayminerals, the increasing rate of colloidal humus content contributes to larger soil plasticity. Statistics also proved positive and strong correlation (r=0.822) between the soil plasticity and humus content. In the case of pH, only a small part of the orchard is has to be limed, since most of the orchard has neutral pH, which is advantageous for nuts and stone fruits. It has to be mentioned, that the CaCO3 supply is also appropriate for the stone fruits. Based on the results hyperspectral imagery can be a good solution for detecting calciferous soils, although these measurements are still need validation.
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Illumination-Independent Reflectance Information Acquirement for Leaf Water Potential Measurement on the Example of Satsuma Mandarin
75-79.Views:129Mandarin fruit sugar content can be increased when subjecting the satsuma mandarin tree (Citrus unshiu MARC. var. satsuma) to moderate water stress by mulching during the period of active sugar accumulation, thereby fruit quality improvement can be realized. In the frame of the precision agriculture production system, a non-destructive measuring method development became necessary based on remote sensing, field spectroscopy and image analysis, to be able to measure the degree of water stress. Large amount of visual information have been recorded at ground level, in near infrared, red and green channels by a false color digital camcorder designed specially for remote sensing applications. A method have been found to be able to calculate the absolute reflection of mandarin leaf surface by comparing leaf reflectance with known reference target reflectance, thereby established the basis of further studies in this topic. Leaf absolute reflection can be measured reliably, under variable natural illumination at field conditions. Functional correlation can be searched between visual information and leaf water potential measured by PMS pressure chamber.
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Spectral properties of strawberry plants
17-22.Views:266Strawberry varieties were studied in 3 different growing areas of different soil- and ecological properties in Hungary. We have measured the optical spectra of the leaves together with their nutrient content and performed sensory examinations on the deep frozen and melted fruit. The 6 varieties were Elsanta, Marianna, Spadeka, Symphony, Camarosa, and Raurica. The 3 sites were Újfehértó, Pölöske, and Kecskemet. Colour of the leaves was characterised by their lightness and dominant wavelength. Under non-optimal soil and ecological conditions the varieties could be distinguished by their colour — the leaves became lighter and more yellow. The fruits did not produce the genetically determined taste if the plant can not grow in optimal circumstances — we found a negative correlation between the leaf colour in flowering time and the fruit flavour. Leaf colour measurements performed in flowering time make it possible to improve fruit quality by changing the nutrient supply between flowering and ripening.
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Pollen morphology of fruit species
49-57.Views:1208Size and surface morphology of pollen has been studied in 87 twit varieties of 10 fruit species during the period of 1990-1995. No preceding work of that type came to our knowledge, yet.
The samples comprised a wide variety of cultivars included male sterile, self-incompatible, partially self-fertile stone fruits, diploid and hexaploid plums, diploid and triploid apples.
The large number of species and varieties facilitated the comparison of items within and between the respective species.
It was stated that the size, shape and surface morphology of pollen is genetically determined and those data, combined with other variety characters, are suitable for the classification and distinction of varieties.
In assessment of pollen size and shape, their moisture content is crucial. The major diameter of the swollen pollen as well as the length and width of the dry grains are characteristic to species and/or to variety.
The width and shape changes largely with moisture content. Large grains are proper to quince, apricot, peach and almond, medium sizes are found in apple, sweet cherry, sour cherry, European plum, whereas small size is typical to Japanese plums.
The low number of varieties studied does not allow conclusions concerning differences within pears, quinces and almonds as species. In the rest of species, valid differences have been registered as between varieties.
Within species, as apple and plum, the effect of ploidy (i.e. number of chromosomes) was expressed in the size of their pollen. In stone fruit species, the correlation between size. of anthers and size of pollen grains was positive.
Genetic relations between the self-fertile sour cherry varieties of the Pándy type (Debreceni bőtermő, Kántorjánosi, Újfehértói fürtös) as well as the self-incompatible apricots of "giant" fruit size are supposed to be analysed by pollen studies but there did not turn out any decisive conclusion, yet. Other characters also should be considered.
The assembly of pollen characters is decisive in the determination of the variety. The ratio of empty pollen grains, the grain size and the density as well as the size of the pits on the surface are best suited to distinguish pollen lots.
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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:466Beetroot 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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Prediction infection risk on the basis of weather-related factors and Erwinia amylovora colonization in apple and pear flowers
39-54.Views:170Current infection risk prediction models utilize environmental parameters and field records, but do not take into account the estimated inoculum potential within the orchard. The object of this study was to survey the accuracy of three simple prediction methods under Hungarian climatic conditions, which could easily be used by the farmers. We also tested whether the accuracy of infection risk predictions can be improved by taking into consideration the incidence and/or rate of flower colonization by Erwinia amylovora.
After preliminary investigations in 1999-2001, data concerning the weather-related infection risk were recorded in 5 apple and 1 pear orchards in 2002, and in 12 apple and I pear orchards in 2003. The weather data were processed by the easy-to-use risk assessment models of the mean temperature prediction line (MTL), Smith's Cougarblight 98C and Billing's integrated system (BIS), and by the MaryblytTM 4.3 computer-assisted model for reference. The population size of E. amylovora in the flower samples was estimated within an order of magnitude by PCR.
For all years and orchards tested, Maryblyt indicated 35 days on which there was an acute infection risk. The same days were indicated by all 3 methods in 23 cases (66%), 8 days were indicated by 2 methods (23%) and 4 days were indicated by 1 method only. A similarly good correlation was found for prediction of the date of the first massive infection risk: in 2003, for instance, there was a perfectly consistent prediction by all 4 models in 9 of the 13 participating orchards. A coincidental forecast was provided by 3 of the 4 models in the other 4 orchards.
The results indicate that any of the risk assessment models could provide an increased accuracy of the actual infection risk prediction if combined with an estimation of the incidence of Erwinia amylovora colonization in the open flowers. We found no convincing differences in the size of the epiphytic population in flowers of cultivars possessing high or low susceptibility to Erwinia amylovora.
We conclude that the easy-to-use methods tested could be used by the fanners to recognize weather-related risks, especially when coupled with an estimation of the proportion of the pathogen-infested flowers. This local prediction would provide rapid information (faster than the regional forecast systems) specifically for a given orchard.
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Effects of aromatic cytokinins on structural characteristics of leaves and their post- effects on subsequent shoot regeneration from in vitro apple leaves of 'Royal Gala'
41-46.Views:185The effects of different aromatic cytokinins applied in different concentrations and combinations were investigated on the histology of in vitro apple leaves and their post-effects on subsequent shoot regeneration from these leaves were studied. Great differences in the anatomical structure of leaves could be detected originating from media containing different types and concentrations of aromatic cytokinins. The number of regenerated shoots per explant and the organogenetic index were used for the evaluation of the post-effect of aromatic cytokinins on shoot regeneration. The histological structure of leaves used for regeneration and their regeneration response showed a good correlation. When the pre-treatment caused a juvenile-like or less-differentiated structure, the number of regenerated shoots per explant increased and often vitrification also decreased and consequently the organogenetic index also increased. A strong interaction between cytokinin-content (type and concentration) of the pre-treatment medium and that of the regeneration medium could also be detected.
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Comparative study of different fertile groups in plums
71-76.Views:182The plum traditional fruit species in Hungary, several local cultivars was born in the different grower's districts. The author that investigated, that are morphological differences between an odds find self-fertile, self sterile (with functional stamens) and male sterile plum cultivars. For it thought about main questions of a scientific debate sown up and the study this way gave reactions totalize. There were in three fertile groups 8-8 type of feature plum cultivars in periods of 1992-2001, respectively 1993-1999. It was founded by author big odds found the troops on the basis of 9 traits between. Pistil length of self sterile cultivars very typical, such as sesquipedalian flower peduncle of the self-fertile plums and the hypoandry of male sterile cultivars. The relative stamen number and the pollen viability as well significant odds gave.
The average fruit mass and sharka infection of self-fertile plums this troops extreme work. According to cultivar's averages the shark symptoms standard the right correlation the singular traits, but those one part of her with each other not shown connection.
The annuity potencies underdeveloped the troops behind and the troops within cultivar's differences had case significance. The results usable the male sterile cultivars and progeny further its investments.
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The morphology of stigmata in stone fruit species
45-48.Views:327The morphology of the stigma has been studied in 50 varieties belonging to 6 stone fruit species. The majority of samples had elliptical stigmata with some exceptions with circular form (Duane, Tuleu gras). The surface of the stigma is papillary, flattened in side view (sweet cherry) or bulging (apricot, peach). The suture of the stigma is clearly visible as a depression and the varieties may differ in this respect.
The size of the stigma depends highly from the season, although the varietal differences are maintained. The dimension of stigmatic surface is characteristic for the species expressed in square millimetres: sweet cherry 0.92 to 2.91; sour cherry 1.64 to 2.48; plum 0.83 to 1.80; oriental plum 0.53 to 1.15; apricot 0.57 to 1.69 mm2.
The size and morphology of the stigma changes according to varieties too, and it may used in description and identification of varieties. No correlation has been found between the size of stigma and the fertility relations (self-fertility or self-incompatibility) of the respective varieties.
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The effect of different cytokinins on chlorophyll content and morphological features of in vitro Nidularium ’Kertész Jubileum’
47-51.Views:258During in vitro multiplication of Nidularium ‘Kertész Jubileum’, 20 g/l sucrose, 5 g/l agar, 100 mg/l inositol, and different concentrations of benzyladenine (BA), benzyladenine-riboside (BAR), kinetin (KIN), meta-topolin (mT) were added to the MKC (Knudson, 1946) basal medium. Furthermore, 0.1 mg/l naphthaleneacetic acid was used to every medium. Number of shoots, length of leaves, number and length of roots, chlorophyll (a+b) content were examined and evaluated with Ropstat statistical software. As compared to the other cytokinin, significantly most shoots were obtained in the case of applying BA. Increasing of BA-concentration (as far as 2 mg/l) enhanced shoot number (from 10.92 to 19.26) but 4 mg/l BA resulted only 6.63 shoot. The less efficient cytokinin was KIN, in most cases no more than about 2 shoot was achieved. Regarding the length of leaves, the higher level of BA effected averagely the shorter leaves (from 24,46 to 7.31 mm). KIN effected significantly the longest leaves (43.4-61.29) in inverse proportion to the concentration. The same cytokinin resulted the most (and the longest) roots with the highest rooting percentages, but more KIN decreased the number and length of roots (from 7.95 to 4.4 and from 38.49 to 22.73 mm). There were no definite correlation between cytokinin concentration and chlorophyll (a+b) content, but the highest doses resulted decreasing (except of meta-topolin which leads to the lowest values). Summarizing, BAR effected the highest contents (mostly more than 1400 μg/g), particularly in the case of 1 mg/l (1807.3 μg/g).
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Carbohydrate utilization of Erwinia amylovora in vitro
31-34.Views:188Nectar is a multi-component aqueous solution that promotes bacterial multiplication. The concentration of nectar in plant flowers is not stable since it is under the influence of environmental conditions, especially free moisture and relative humidity. Experiments were conducted with "artificial nectar" and directed along two lines: (1) determination of the optimal concentrations of carbohydrates for the growth of E. amylovora development (2) consumption of different carbohydrates besides basic sugars.
Solutions of "artificial nectar" were prepared in different compositions by changing the dominance of basic sugars (fructose — glucose —sucrose) in proportions of 2:1:1, 1:2:1, 1:1:2 and between concentrations of 10-0.6% (diluted with Basal minimum broth) in order to determine optimal conditions for the development of E. amylovora.
At a basic sugar concentration of 10% bacterial multiplication started and continued until I log degree (from 106 to 107 cfu/ml). At concentrations of 5% and 2,5 % cells developed with nearly the same kinetics (from 106 to 8x107 cfu/ml and from 106 to 9x107 cfu/ml, respectively). Multiplication was more pronounced and nearly the same at concentrations of 1.2 % and 0.6 % (from106 to 2x108 cfu/ml). At a basic sugar concentration 30% total sugars bacterial multiplication did not occur, while at 20 % it was negligible, not measurable photometrically.
At minimal concentrations of F, G, S (between 1-0.1 %) bacterial cells were still able to multiply, producing organic acids from sugars.
Our study showed that E. amylovora requires only a small amount of sugars (0.1%) for multiplication (acid production) while high concentrations inhibit multiplication. There was a negative correlation between sugar content and cell density. The optimal range of sugar concentration was at about 1%.
Effect of "less frequent carbohydrates" to E. amylovora multiplication was also determined using the API 50 CH strip. We could provide information on utilization of 39 carbohydrates by the bacterium at different categories as follows: Not utilized-, Slowly and weakly utilized-, Slowly and completely utilized-, Quickly and completely utilized carbohydrates. We suppose that carbohydrates that belong to the latter two groups could play an important role as nectar components in promoting E. amylovora multiplication in the blossoms of pome fruit trees.
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The application of A HEAT SUM MODEL for the budburst of sour cherry varieties grown at Újfehértó
105-112.Views:320Experiences of the last decades showed univocally that the climatic changes, especially the warming up, influenced clearly the phenology, i.e. speed of growth and development of plants. To check the effects, the phenological studies became a topic of special interest. Our research has been performed at Újfehértó, the Research Institute of Fruit Growing and Extension, where the respective database accumulated observations during the period 1984–2005, where the meteorological data as well as the parallel phenological diary referring to the varieties ’Újfehértói fürtös’, ’Kántorjánosi’ and ’Debreceni bôtermô’ during the period 1984–1991 have been utilised. The method of calculating the sum of daily mean temperatures, “degree days”, is based on the observation that the plants are able to utilise cumulatively – in growth and development – the temperature above a set basic temperature. Our phenology model examined the correlation between the sum of degree days and the date of sprouting (budburst). The basic temperature has been determined by optimization, above which (threshold temperature) the accumulation of daily means was most active, or alternatively, below which the daily means are most sensitively expressed in the phenology. The model has been extended to the calculation of the end of rest period (endodormancy) – by optimization as well. Our phenology model will be suitable for two main purposes: for estimating the time of budburst for the Hungarian region during the next decades calculated on the basis of regionally downscaled climate models; on the other hand, by applying our model, the risk of damage caused by spring frosts could be estimated more exactly than earlier.
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Overwintering capability and spring population size of honeybee colonies (Apis mellifera L.) in Hungary
153-156.Views:126Honeybee races and ecotypes of different genetic background have different population development in spring. Some of them can reach the necessary population size by the beginning of Robinia pseudoacacia (black locust) blooming period. There were significant differences in the spring population development between the colonies of different genetic background. The Italian races (A. m. ligustica) and their cross-breeds over-wintered poorly in Hungary, their spring population was low and they collected small amount of Robinia honey. The Austrian improved Carniolan (A. m. carnica) colonies over-wintered well, they had the largest spring population in both years. There was no significant difference between the size of the spring population of the same colonies of different genetic background in 1995 and 1996. The rate of the population development of the colonies was different in the two examined years. There was strong correlation (r = 0.8) between the spring population size and the Robinia honey yield, and between the mid-April population size and the Robinia honey yield of the colony groups of different genetic background. Spring population size also important in the effective pollination of fruit tree species that bloom earlier than the black locust trees.
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Organoleptic evaluation of sweet cherry varieties
7-13.Views:672The 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 the 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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Stimulating effect of distilled water
47-49.Views:155It is an early observation that plants in poor soil are developing roots quicker and more abundantly than on rich one. There is a similar correlation between the nutrient status of medium and adventitious root formation.
In order to throw more light on the background of this strange phenomenon we started a systematic experimental program in which the biological effects of distilled water as model factor was investigated.
The experiments proved that the root formation of Pinto bean (Phaseolus vulgaris L.) cuttings with 3 cm long hypocotyls was promoted by distilled water.
The phenomenon above accompanied with slower decline and faster recovery of total and also water-soluble protein content, more intensive efflux of amino acids, greater amount of tryptophane and increased uptake of water compared to those in control hypocotyls. From other data obtained we may suspect that some additional active substance unknown for us also contributes to the stimulation of root initiation in distilled water.
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Flower characters and self-fertilization capacity in relation to the bee pollination at sour cherry cultivars
121-132.Views:211Detailed studies and comparisons were carried out on those flower characters of sour cherry cultivars that may affect bee pollination of flowers. Flower characters of sour cherry are fairly similar to other temperate zone fruit tree species. Their relatively small flowers distinguish the Cigánymeggy-types of cultivars from the flowers of tart cherries cultivars that are conspicuously larger, almost as large as the sweet cherry flowers. The relative position of flower organs was much more variable according to the season than according to the cultivars. So the differences were rather the consequences of seasonal effects than of variety features of sour cherry cultivars. As far as individual cultivars are concerned differences in the nectar production and the sugar concentration are revealed rather between groups of cultivars than between individual cultivars. The pollen production of flowers was extremely changeable in consecutive years. Most honeybees collected nectar at sour cherry flowers; pure pollen gatherers and mixed behaviour bees were half as frequent but differences among the behaviour of honeybees according to cultivars cannot be stated. The fidelity of honeybees to sour cherry is less expressed than to some other fruit tree species. Accordingly, it is very strongly suggested to take the competitive effect other plant species (weeds) flowering in and around the orchard carefully into account when organizing additional bee pollination in sour cherry plantations. Several sour cherry cultivars possess more or less self-fertilization capacity but this is greatly changeable according to the season. It has been proved that self-sterile sour cherry cultivars are sensitive even on the partial restriction of the effective time of bee pollination and it is to be stressed too that even in the case of partly self-fruitful cultivars bee pollination is also vital in yield formation because medium or strong restriction of the effective bee pollination period is of a definite negative effect on their fruit set and yield. In years with unfavourable weather the yield can dramatically be reduced sometimes down to nil. However, very high fruit set is also unfavourable because a negative correlation was detected between the final set and the mean mass of fruits.
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Harvest and postharvest brown rot of fruit in relation to early latent infection caused by Monilinia spp. in Hungary
17-19.Views:254In this study, the effect of early latent infection caused by Monilina spp. on harvest and postharvest brown rot of sour cherry and peach was investigated. Two field experiments were performed in commercial orchards located at Eperjeske on sour cherry and at Siófok on peach in 2013 and 2014 in order to study the possible relationship between the incidence of early latent infection caused by Monilinia spp. and the incidence of harvest and postharvest brown rot. No latent infection was recorded at popcorn phanological stage of the trees at both locations. The maximum incidence was detected during the pit hardening period. There was a positive correlation between the incidence of latent infection and harvest or postharvest brown rot. The average incidence of latent infection during the crop season explained approximatelly 20% of the total variation in the incidence of postharvest brown rot.
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Path coefficient analysis of environmental factors influencing flight activity of Apis florea F. and seed yield in carrot (Daucus carota L.)
87-92.Views:138Foraging ecology of insect pollinators visiting carrot flowers (Daucus carota L.) was studied in relation to five environmental variables. The dwarf honeybee, Apis florea L., was the most abundant flower visitors and comprised more than 94% of the total flower visiting insects. Commencement of flight activity occurred when a minimum threshold of environmental variables was surpassed while the cessation was governed mainly by decline in values of light intensity and radiation. In between the commencement and cessation, the foraging population correlated significantly and positively with air temperature, light intensity, solar radiation and nectar-sugar concentration and negatively with relative humidity. Path coefficient analysis, however, revealed that direct effect of temperature was high and positive followed by light intensity and solar radiation while the direct effect of relative humidity was high and negative. The direct effect of nectar-sugar concentration was negative and negligible. Evidently, path coefficient analysis gave a more clear picture of effects than did the simple correlation analysis. Apis florea on an average visited 1.14+0.23 and 22.78+2.57 umbels and flowers/min, respectively during different hours of the day. Furthermore, the insect pollinated plots produced significantly more seeds with heavier weights than those isolated from insect visits.
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Sugar composition of floral nectar in sour cherry cultivars
109-113.Views:208The composition of floral nectar in sour cherry cultivars studied in 1997 at Újfehértó was in agreement with our previous data, the three most frequent sugar components being glucose, fructose and sucrose. Nectar secreted at night is generally more diluted than nectar produced during the day. None of the nectar samples produced at night reached the threshold value (100 mg/ml) of bee visitation. In the majority of cultivars the difference in concentration between night and day nectar is not too high, but in two cultivars, 'Korai pipacs' and ‘Újfehértói fürtös’ the difference is quite significant. Most sucrose was found in the nectar of cvs. 'Érdi jubileum' and ‘Újfehértói fürtös’, but a high amount of sucrose was measured also in the flowers of 'Korai pipacs' and 'Meteor USA'. Nectar concentration varies from opening of the flower to petal fall to a smaller or greater degree, depending on the given cultivar. From the 9 sour cherry cultivars studied ‘Újfehértói fürtös’ and Tandy 48' had the most attractive nectar for bees. There was no correlation between nectar composition and free fertilisation. On the basis of nectar composition the majority of the sour cherry cultivars studied can be classified into the sucrose-rich category; only one cultivar, 'Érdi jubileum' had a sucrose-dominant secretory product. The composition of nectar in the studied sour cherry cultivars is preferred by bees.
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Rheological evaluation of industrial tomato in raw and processed condition
60-64.Views:233Tomato (Lycopersicon esculentum Mill.) is the second most important vegetable with one of the biggest producing areas worldwide, and an increasing tendency in Hungary as well. To fulfil the growing demands of the industry the producers must use the most suitable genotypes for the given conditions. In the experiment six genotypes (‘Heinz 1015 F1‘,‘Heinz 9478 F1‘,‘Kecskeméti 407‘,‘NUN254 F1‘,‘Prestomech F1‘ and ‘Rustico F1‘) were evaluated for different quality parameters: fruit shape index (length/diameter), firmness (g cm-2), force needed to tear the skin (kg-1) and consistency of tomato puree (g*sec). According to the results, the ‘Heinz 1015 F1‘ and ‘Heinz 9478 F1‘ were the most suitable genotypes for industrial processing in the mean of fruit quality. Strong positive correlation between consistency of juice and fruit shape index (r=0.891) and firmness of berry (r=0.882) was confirmed. The results have proved the necessity of these quality parameter measurements, which are important for the evaluation of raw material.