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Water relations of apple and influence on fruit quality (minireview)
59-63.Views:339The saving of soil water content and the improvement of adaptability of plants to periodical insufficient water and use of deficit irrigation technology become more important because of the occurrence of frequently dry periods. The water use efficiency of apples can be increased by the choice of appropriate rootstocks and determination of water requirement of varieties that depend on their growing periods and climatic factors. Depletion of soil water resources need to develop efficient irrigation techniques for quality apple production. A new deficit irrigation strategy (PRD) has been developed that based on partial water supply of root-zone. This does not result a decrease in the sizes and yield of the fruit. The larger fruit size and lower firmness in frequently irrigated trees can result in excessive internal growth stresses that cause higher rate of fruit splitting. Many studies revealed the relationship between irrigation and yield quantity. Recent researches investigate the effects of irrigation on apple fruit quality particularly on the colouration and post-harvest quality. Use of cooling irrigation improves the development of coluour an apple fruit but its schedule can influence on the incomes. Aroma volatiles are responsible for odour and contribute to overall flavour of the fruit and its processed products. Deficit irrigation had only affects some volatile aroma but no the all of concentrations in apple fruit. In the future the high apple quality for consumers could be provided with improvement of transpiration-yield model based on the water requirement of varieties and economic irrigation schedules.
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Cracking susceptibility evaluation of some stone fruit species (Sour cherries – Prunus cerasus L.; Sweet cherries – Prunus avium and European plums – Prunus domestica L.) grown in Hungary
45-54.Views:270The rain induced fruit cracking is a big, serious problem especially for sweet cherry growers but in some year growers of other stone fruit species had also problem with fruit cracking caused by too much and heavy rainfalls in the ripening and harvesting season. Cracked stone fruits can be easily infected by different diseases like Monillinia sp. Cracked and infected fruits can not be transported for long distance and using for preservation, they lost their market value by the destroyed fruit quality. It was decided to make a research work to determine the rain fruit cracking susceptibility of few stone fruit species (sour cherries, sweet cherries and European plums). Fruit cracking tests were occurred under laboratory conditions on the most common cultivars grown in Hungary. Furthermore we tried to find correlation between the fruit cracking and some fruit quality parameters (fruit size; total sugar content, fruit flesh firmness).
Our conclusions are the followings:
Sour cherries: There were found differences in the cracking ratio and the cracking dynamics of the tested sour cherry varieties when they were immersed in distillated water for 24 hours. Based on cracking test results under laboratory condition (immersing in distillated water) we made the grouping by cracking susceptibility of sour cherry varieties. Tested cultivars were divided three groups: very susceptible; susceptible; moderately susceptible (tolerant). Groups with varieties are: Very susceptible - ’Maliga emléke’, ’Piramis’, ’Érdi jubileum’,’Érdi nagygyümölcsû’ and ’Meteor korai; Susceptible (Sensitive) – ’Érdi bôtermô’, ’Pándy’ and Cigány 59. Moderately susceptible (tolerant) – ‘Éva’ and ‘Petri’as new rereleases. The most of tested sour cherry varieties are in agreement with the literature (Apostol, 2003) and four of them (’Maliga emléke’, ’Pándy 279’, ‘Éva’ and ‘Petri’) had higher average fruit weight than was mentioned in the literature (Apostol, 2003). Our fruit cracking results are in agreement with Zelinski’s (1964) and Christensen’s (1975) conclusions that there is no close relationship between fruit size and rain induced fruit cracking tendency. We found significant differences between the sugar content of tested cultivars. In contrast of Verner & Blodget (1931) our results confirm Tucker’s opinion that the sugar content is not correlation with the cracking tendency of cherry fruits (Tucker, 1934). Fruits firmness (elasticity) was measured by destructive method when juice was coming out from fruits. There were found big differences of fruit firmness and skin strength of observed cultivars. Our results are only partly agreement with Christensen’s (1996) opinion that cherry cultivars with firmer fruits are more prone to fruit cracking than softer ones. By this was seemingly we did not found close relationship between the fruit firmness and the cracking tendency of sour cherry fruits. We found that during fruits immersing in distillated water the fruit weight was increasing due to the absorbed water. Our opinion is that there is no close relationship between the scale of fruit cracking and the quantity of absorbed water. By results presented above we our opinion is that no very close relationship between the fruit cracking of sour cherries and the observed parameters (fruit size, fruit firmness, sugar content, amount of absorbed water) maybe other varietal effects and physiological characters (fruit skin structural parameters) play more important role in the fruit cracking mechanism of cherries.Sweet cherries: Similarly to sour cherries in the case of sweet cherries we also did not find close relationship between observed fruit parameters and cracking index. It was differences in the cracking ratio and the cracking dynamics of the tested sweet cherry cultivars when they were immersed in distillated water for 24 hours. It was found that the cracking ratio of very cracking susceptible sour cherry varieties had the same or higher cracking index than observed sweet cherries. It is in contrast with the general opinion (Chistensen, 1996) that sour cherries are less prone to rain induced fruit cracking than sweet cherries. We found differences between the cracking ration and cracking dynamic of the same cultivar in different years (2006 and 2013). It is in agreement Christensen’s (1996) opinion that the year effect cause big differences in the fruit cracking of cherries.
European plums: We found differences in the cracking ratio and the cracking dynamics of the tested plum varieties when they were immersed in distillated water for 24 hours. A shorter term (6 hours) immersing in water caused three groups by their cracking susceptibility: „Very susceptible”: ’Révfülöpi’ and ’Szarvasi’; „Susceptible”: ’Besztercei’; „Less sensitive”: ’Bluefre’ and ’Cacanska rodna’. A longer term (24 hours) immersing in water resulted only two groups with significant differences: „Susceptible group”: ’Révfülöpi’, ’Szarvasi’ and ’Besztercei’; „Less sensitive”: ’Bluefre’ and ’Cacanska rodna’ Similarly the cherries we did not find correlation between the fruit size and cracking susceptibility of European plum cultivars. It was based on: the big fruit sized ‘Bluefre’ and middle sized ‘Cacanska rodna’ cracked in the lowest scale, during the small sized ’Révfülöpi’, ’Szarvasi’ and ’Besztercei’ cultivars cracked in higher scale We found positive correlations between the cracking susceptibility and total sugar content of tested plum cultivars. Cultivars with significantly lower sugar content (‘Bluefre’ and ‘C. rodna’) showed lower fruit cracking susceptibility than cultivars (’Révfülöpi’, ’Szarvasi’ and ’Besztercei’) with higher sugar content). We found close relationship between the relative (%) absorbed water amount and the fruit cracking susceptibility. Cultivars with higher absorbed water amount (’Szarvasi’-’Révfülöpi’-’Besztercei’) had higher cracking susceptibility. -
Utilisation of subsurface waters for soilless vegetable forcing in the Southern Great Plain region of Hungary
43-45.Views:155For soilless vegetable production of the Southern Great Plain region in Hungary, there is enough water available, however, the origin and chemical composition of it are decisive from the point of view of practicability. The ground water is everywhere accessible, although its sodium and chloride content is almost always significant, moreover, human pollution may occur (e.g. nitrates and phosphates). A further unfavourable moment is the seasonal variation observed within the area of the same community. The abundant supply of water in the Quaternary strata are located in more than half of the cases within the upper 50 m region. As by the expected changes of the climate, a strategic increment of the importance of subsurface waters is anticipated. Their composition is relatively stable, and the prognoses are reliable for the same settlement. Salt content of the majority of water resources bearing hydrocarbonates is low, however, streaming of the subsurface waters tend to increase their sodium content and to diminish their calcium and magnesium, whereas the pH increases (mainly by ion-exchange). Water quality is decisive not only because of the interaction with the plants but also from the point of view of the distribution of water. Some micro-elements, mainly iron and secondarily manganese may cause problems, therefore, irrigation water ought to be prepared carefully. Production technology should be completed by a technical equipment using aeration for the elimination of ironinfluence of yields on rate of return of investment; (3) the role of increasing of added value content of products. Importance of the utilisation of alternative channels of distribution and the formation of producers' cooperatives are underlined, being based on calculation of return of investment.
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Postharvest methyl jasmonic acid and hot water can reduce the internal breakdown and quality loss of apricot fruit at shelf life
31-34.Views:233The aim of this study was to investigate the postharvest effect of methyl jasmonic acid (MJ) and hot water on internal break-down and quality loss of apricot fruit under shelf life conditions. Cultivar Flavor cot apricot fruit were used to treat with water as control treatment, with 0.2 mmol/L MJ and with hot water 35 oC for 5 min. Fruit were stored at room temperature and were examined every 2 days for internal break-down and quality loss. Results showed that treated fruits with MJ and hot water showed the lowest weight loss and the highest firmness during all assessment times. Control fruits showed losing of customer acceptance from the day 2 of shelf life and then decreased dramatically to approximately loss all the acceptance at day 8. The SSC showed sever reduction in untreated fruit after day 6 at shelf life. Total phenol content reduced and polyphenol oxidase (PPO) increased in all assessment times for all treatments. Meanwhile MJ showed the best values for phenol content and lowest PPO activity. The results supported the idea of using some elicitors like methyl jasmonic and hot water treatments to enhance shelf life of apricot fruit.
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The role of meteorological variables of blossoming and ripening within the tendency of qualitative indexes of sour cherry
7-10.Views:246We analyzed the relationship to sour cherry quality parameters of average temperature, maximum temperature, minimum
temperature, night and day-time temperature, precipitation and climatic water balance variables. Three cultivars of sour cherry were included
in the selection: “Debreceni bôtermô”, “Kántorjánosi”, and “Újfehértói fürtös”.We conducted regression analyzes on the three varieties, but
present only those that proved to be the best fit.We couldn’t find any significant differences in the weather tolerance of the varieties. The data
base of sour cherry quality parameters covers the 1998 to 2008 intervals. The researched parameters were the following: dry matter content
(%), sugar content (%), C-vitamin (mg), total acid content (%). Maximum temperature, the difference of night and day-time temperature and
minimum temperature all have a significant correlation with the investigated quality parameters of sour cherry. Minimum temperature shows
a quadratic relationship with sugar content, while night and day-time temperature differences show the same with dry matter content. The
other weather parameters had a linear correlation with the quality parameters of sour cherry. The research results show that an increasing
amount of precipitation causes decreasing tendency in total acid content of sour cherry, so that increasing temperature has a positive influence
on total acid content. Big differences in night and day-time temperature also has positive effects on the dry matter and sugar content of sour
cherry while the amount of precipitation has a negative effect. High minimum temperatures cause decreasing sugar content respiratory energy
losses are significant if dawn temperatures do not drop considerably.A more favourable climatic water balance has a positive effect on vitamin
C content in cases of a large negative water balance, vitamin C content is generally low. -
Water relations of sour cherries (minireview)
103-107.Views:218Recently, the sour cherries as food resources become more important for health preservation and so the modernization of growing technology in sour cherry production will be timely. The global warming and inadequate distribution of precipitation result a decrease in the alternancy of sour cherry production, as well. Sour cherries rather adapted to survival of drought than sweet cherry trees therefore a few studies performed to explore the water requirement of sour cherry varieties. The rootstocks, the type of soils in plantation and the water balance influence the water management of sour cherries. In orchards, in particular first year plantation, use of various row covering contribute to preservation of the natural water pool of soil and affect on the tree vigor, yield and fruit quality. Wide-spread application of integrated fruit growing technology and climate changes the researches are pointed to develop efficient irrigation technology based on transpiration yield model. The crop model based on use of meteorological data was developed for cherry orchards in order to predict transpiration of trees, dry matter production and fruit yield. The linear relationship between dry matter accumulation and transpiration was verified for sour cherry trees. Other models essay to asses the effects of climate changes on crop production. Importance of economical production and fruit quality such as ingredients of raw materials and food increases in intensive sour cherry orchards used by irrigation techniques. Because of climate changes it should more pay attention to research concerning on the stress physiological response of sour cherry varieties and post-harvest fruit quality.
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Determination of chlorophyll content in case of peach leaf curl disease (Taphrina deformans) with spectral analysis
49-52.Views:347One of the most important conditions of high quality fruit production is the early detection of hytopathologycal infections. The most dangerous disease of peach (Prunus persica) is the Taphrina deformans, which causes serious damages mainly in the years where the weather condition is cool and wet. In this study, healthy and naturally diseased leaves by peach leaf curl were investigated in the laboratory of University of Debrecen, CAAES, Institute of Water and Environmental Management. Both of hyperspectral measurement and the values of spectrophotometer shown the chlorophyll content of diseased leaves were lower than the healthy samples. Based on the experiments the water status of investigated leaves established the infected leaves contained more water in their tissues.
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Colour and water content detection of sweet cherry by portable spectrometer
23-26.Views:319Based 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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Effect of water supply on canopy temperature, stomatal conductance and yield quantity of processing tomato (Lycopersicon esculentum Mill.)
13-15.Views:297Tomato (Lycopersicon esculentum Mill.) is one of the most extensively cultivated horticultural crops in the world.Water supply is important for yield quantity and quality. The aims of the present study were 1) to evaluate the canopy temperature and the stomatal conductance on processing tomato substances with different water supply, 2) to investigate the effect of different water supply on yield quantity. There were two irrigated treatments, one of them was the reguralry irrigated plant stand which got 333 mm water during investigated period, including the precipitation and the other was the cut off substance which means the irrigation (drip) was stopped at the beginning of the ripening process and there was a control as well which got 189 mm precipitation. The canopy temperature was measured row by row with a Raytek MX 4 type infrared remote thermometer. The stomatal conductance was measured by Delta-T AP4 type porometer. There were significant differences between the control and irrigated plants according to the water supply which was formulated the canopy values. The plants with a deficient water supply were decreased the transpiration rate, therefore its cooling effect didn’t show up. The regularly irrigated tomato plants’ yield exceeded the unirrigated ones more than twice. It is emerged from the study that the irrigation has a positive effect on the amount of the harvestable yield in this year type.
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Effects of Foliar Nutrition on Onion Seed Storage under Controlled Atmosphere
101-110.Views:220Storage of fresh fruits and vegetables prolongs their usefulness. The principal goal of storage is to preserve the commodity in its most useable form for the consumer. The extension of storage life and the improvement of quality of fresh fruits and vegetables can be supplied by harvesting at proper maturity, control of post-harvest diseases, chemical treatments, refrigeration, controlled and modified atmospheres. Two successive winter seasons of 2008/2009 and 2009/2010 were conducted under sandy soil conditions to study the effect of spraying with 12 commercial compounds on onion seeds and storage under controlled atmosphere. The germination percentages were 85.50, 86.85, 83.75 and 82.15 for CA1, CA2, CA3 and CA4, respectively. Water content of onion seeds was significantly increased with decreasing storage temperature in all controlled atmospheres. Water content values were 4.48, 4.40, 4.55 and 4.54 for CA1, CA2, CA3 and CA4, respectively. There were significant decreases in water content with increasing exposure periods. The lowest water content was recordednfor the exposure periods of 120 and 240 days. Catalase and peroxidase activities were decreased with the decreasing of storage temperature, whereas malondialdehyde content was increased. The exposure for 120 days recorded the highest catalase activity. The highest value of peroxidase (11.72) was recorded for CA2. Peroxidase activity increased as exposure period increased until 120 days and then decreased. Cold storage temperature (5°C) showed the highest malondialdehyde content followed by room temperature. The CA2 showed the lowest malondialdehyde content compared with other controlled atmospheres. The exposure period of 120 days had the lowest malondialdehyde content.
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Effects of salinity stress induced by hot spring water on tomato growth, yield and fruit quality under hydroponic cultivation in Japan
23-28.Views:147The objective of this research was to test hot spring water as a source of salt to improve tomato quality under the hydroponic system. This research was conducted at Yamagata University, in Japan from February to July 2017. Salt stress was induced using salts of hot spring wastewater collected from Yupoka Onsen (Tsuruoka, Japan). The treatments were EC 2, 4, 8 12, and 16 mS/cm which were arranged in a Randomized Complete Block Design (RCBD) with five replications. Tomato plants were grown at EC 2 until flowering and then subjected to different EC concentrations until harvesting. The data were collected on plant growth parameters and fruit quality. Fruits were harvested at the red stage until the 5th truss. The results showed that fruits' Soluble Solids Content, organic acid, Nitrate contents and Sugar: Acid ratio increased significantly at EC 16 mS/cm and in the upper trusses compared to EC 2 and in the lower trusses. In contrast, fruit weight significantly decreased at EC 16 mS/cm and in upper trusses. Leaf thickness, size and SPAD, and specific leaf weight significantly declined at EC 16 mS/cm and upper leaves compared to EC 2 and in lower leaves. Plant height started to decline significantly after three weeks of treatment at EC 16 compared to EC 2.
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The effect of storage to optical properties in case of two apple fruit varieties
33-36.Views:268The keeping quality of fruits is a very important factor in storage point of view, since it could be elongated the consumption time of fruits. In many cases the storage may be necessary, e.g. in short time it is not able to market due to the rich harvest, or all fruits could sell in markets throughout the year. The keeping quality of various fruit species is greatly different; moreover it could be observed some differences between the varieties as well. In our research, we have investigated the spectral properties of the external surface and fl esh of two ripe apple varieties – Jonagored and Granny Smith – before and after storage (about 3°C and about three weeks). The hyperspectral investigation was carried out with AvaSpec-2048 Fiber Optic Spectrometer. The experimental results represented the differences between healthy and chilling injured apple fruits. Furthermore, some indices were created to given countenance to the spectral differences.
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Foliar Nutrition and Post-Harvest of Onion Seed: Effects of storage temperatures, storage period and foliar nutrition
29-47.Views:223The aim of onion bulb storage is to meet consumer demand for extended availability of onions whilst maintaining product quality. The principal biological factors leading to onion bulb deterioration are respiration, resumption of growth and pathogen attack. In onion bulbs a dormant period, when sprouting and rooting cannot be induced, is followed by a period of internal changes that prepare the bulb for breaking of dormancy and subsequent growth. Out of storage, the bulb then proceeds towards flowering and seed production. Two successive winter seasons of 2008/2009 and 2009/2010 were conducted under sandy soil conditions to study the effect of spraying with 12 commercial compounds on yield and yield components of onion seeds and storage The seed yield of each commercial compounds plot from previous experiment was divided into two groups, storage under room temperature and 5°C. Seeds transferred immediately after drying to Increasing Export Competition of Some Vegetable Crops Project Laboratory located in Faculty of Agriculture, Cairo University. The effects of storage temperature, storage period and foliar with some commercial compounds on onion seed quality were considered. Storage in 5°C had the higher germination percentage than storage in room temperature. Results indicated that as storage period increased the germination percent decreased. The treatment with boron or amica in the first season had the highest germination percentage. While, the treatment with union Zn, union feer, union Mn, boron, elga 600, caboron, amica, hummer or amino X had the highest germination percentage in the second season. Storage in 5°C resulted in higher moisture content than storage in room temperature. Regarding the effect of storage period on moisture content, the water content was significantly increased with prolongation of storage period. The lowest values of water content were recorded for treatments with union feer, shams K or boron in the first season, and union feer, shams K, boron, magnesium, shetocare or hummer in the second one. Catalase activity was significantly decreased as storage period increased. The treatment with shams K, boron, shetocare or amino X had the highest catalase activity in both seasons. Peroxidase activity was significantly decreased as storage period increased. Foliar application with boron had the highest peroxidase activity in both seasons. Seed stored in room temperature had the higher malondialdehyde content than those stored in 5°C in the second season. The malondialdehyde content increased as storage period increased. The treatment with magnesium, caboron and the control in the first season, and the treatment with magnesium and the control in the second season had the highest malondialdehyde content.
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Vineyards characteristic by using GIS and refl ectance measurements on the Nagy-Eged hill in Hungary
57-60.Views:211Our investigation was carried out in vineyards on Nagy-Eged hill in Hungary. Grapevine growing plays an important role in Eger Vine Regions. In the grapevine cultivation it becomes necessary to know the requirements of vineyards along the best geographical situation using available cultivation and examination technology to achieve better and quality produce. This study reviews applicability of the different spatial analyst techniques in vineyard especially models based on surface relief and the new technology of hyperspectral analysis. The spectral alteration was examined between different health status and leaves infected by Eriophyes vitis to defi ne spectral characteristics. Thus reflectance measurements could also support to evaluate airborne hyperspectral images with the help of the spectral library.
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Influence of soaking periods and temperatures on germination and respiration of pea seeds
69-71.Views:233Samples of 50 wrinkled-seeded pea (Piston sativum cv. ‘Farida') were soaked for 0.5, 1, 4, 8, 24, 48 and 72 hours at temperature of 5, 10, 15 and 20 °C in distilled water before germination. Water absorption, percent of germination, vigorous seedlings and dry weight of normal seedlings were assessed after 8 days. Respiration of short and long seedlings were checked by IRGA, LI-COR 6200 photosynthesis system. Most plants had more or less respiration but some of them already had photosynthesis. Differences in the amount of water absorbed were evident after one hour, only. Water amount was increased by increasing soaking temperatures and times. The maximum was achieved after 24 hours. Normal germination percent was not improved at any soaking time and temperature combinations but it was significantly declined at 10 °C with soaking time combinations and at 20 °C for 72 hours. The seedling vigour values were not very different at the higher soaking temperatures, but the treatments at 20 °C temperature with 8 and 24 hour soaking periods are proved to be optimal for seedling vigour. At the low soaking temperature the increase of the soaking period influenced the seedling vigour. Reduction of dry weight percent was noticeable by any soaking time related to temperature and compared with the control.
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Foliar application of zinc and its effect on greenhouse grown cucumber
79-82.Views:185The 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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The effect of soil coverage on the soil quality
77-80.Views:127In this study we carried out experiments with soil samples originated from the Haschberg variety elderberry orchard and wild-growing plants from Szigetcsép Experimental Farm.
During the examinations we wanted to know how the black polyethene foliar soil coverage influences the quality of soil and the distribution of different nitrogen forms.
We studied the individual covered (foliar soil coverage for every plant), the full covered (foliar soil coverage was laid in the rows) and the uncovered threatments.
During the experiments we pointed out that the foliar coverage influences the condition of the soil unfavourably. Because of the coverage there is less air flow in soils, the lack of oxygen leads to degradating of soil life and results humus materials of poor quality.
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The necessity and possibilities of irrigation in fruit growing under conditions of Hungary
93-94.Views:239Climatic and soil conditions are highly suitable for most temperate fruit species and promise profitable yields with good quality. An accurate choice of the growing site is, however, decisive because of the wide range agro-climatic variation an soils within the country. One of the most important factors is the annual precipitation which does not exceed, in general, 700 mm. The aims of irrigation practices are, succinctly speaking, the improvement of quantity and security of yields and the guarantee of quality. The relative importance of those criteria changes according to the fruit species. In up to date apple, pear and cherry production, micro-irrigation systems are mainly considered. According to recent experiences, the micro-jet type of water distribution should be preferred to the dripping system. In cherries, the choice of the method is motivated by the need to prevent fruit cracking. Most of the peach and apricot plantations are located on the dry and moderately dry regions of the country. Because of the late freezes, the improvement of security is crucial. There the investment of irrigation systems should concentrate to the possibility of anti-freeze sprays. High water requirements of plums are met in Hungary by irrigation where the method should be decided at the plantation and adapted to the harvesting procedure which could be mechanised or (in high density plantations) picked by hand. Sour cherries are perhaps the less dependent on watering under Hungarian conditions. Yields in small fruits: currents, gooseberries, raspberries and strawberries could be increased by irrigation to 40-50 % and may improve quality too. In those cultures the system of moving flexible wing tubes are considered to be the best irrigation technique.
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Illumination-Independent Reflectance Information Acquirement for Leaf Water Potential Measurement on the Example of Satsuma Mandarin
75-79.Views:121Mandarin 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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Review on rain induced fruit cracking of sweet cherries (Prunus avium L.), its causes and the possibilities of prevention
27-35.Views:807The rain induced fruit cracking is a big, serious and costly problem for cherry growers. Cracked fruits lose their value and they are not marketable because of the poor fruit quality. Cracked fruits have different storage diseases and shorter storage and shelf life.
There are many influencing factors of the cherry fruit cracking such as: water uptake; fruit characteristics (fruit size, fruit firmness; anatomy and strength of the fruit skin, stomata in fruit skin, cuticular properties, osmotic concentration, water capacity of the fruit pulp, growth stage of the fruit,); orchard temperature and other environmental conditions;
The most effective protection technique is the plastic rain cover over the tree rows. The installation of these equipments is too expensive for the cherry growers. That is the reason why researchers tried to find other less expensive and sufficiently effective ways against the Lim induced fruit cracking.
Several calcium formulas: calcium chloride (CaC1,), calcium hydroxide (Ca (OH)2) and calcium nitrate (Ca(NO3)2 ) can be sprayed in appropriate concentration. Spraying with other mineral salts (aluminium and copper salts, borax) and PBRs (Plant Bioregulators) may be also effective to reduce fruit cracking.
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Structural differences arise between fruit cuticles of two apple cultivars during long term cold storage
26-29Views:274Apple fruits are covered by hydrophobic cuticle that provides protection against desiccation, pathogens, excessive water absorption and radiation. The features of cuticle affect the quality and storability of the fruits. It was aimed to evaluate the correlation between peel ultrastructure and weight loss in fruits covered by waxy bloom (cv. Florina) and without bloom (cv. Red Rome van Well) during 4-month cold storage. SEM (scanning electron microscopy) was used for visualization of the fruit surface and fruit weight was also measured. Several studies have revealed that there may be correlation between the ultrastructure of cuticle and its water permeability. Our results confirmed this phenomenon in case of two cultivars. The weight loss per fruit surface area unit of ‘Florina’ was found significantly higher than that of ‘Red Rome van Well’. At the same time the cuticular surface of the fruits contained more micro-cracks in case of the former cultivar. These data confirmed the relationship between the density of cuticular micro-cracks and the water vapour permeability. We concluded that this feature is more significant than the amount of natural waxy bloom on fruit surface.
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Changing of inert content values of apricot varieties
39-41.Views:193The consumers have been exigent increasingly about excellent quality. The speci fie flavour and fragrance of apricot evolve during ripening. We need to be acquainted with changing of inert content during ripening to the choosing of optimal harvest time. The Regional University Knowled ge Centre -Research and Development in Foodstuff Chain project had presented an opportun ity to study the inner content of apricot. Our aim was to study evaluation of health care attributes of apricot fruit. We investigated different ripeness samples of four apricot varieties ('Mandulakajszi', 'Pann 6nia', 'Gonci magyar kajszi'. 'Harcot') in our study of 2007-2009. Samples were taken the orchard of Sóskútfruct Ltd. Hungary. We had measured the water soluble antioxidant capacity, polyphenol-, f3-carotene content and the dissimilar sugar and acid-fractions during ripening. We had experienced significant different in inert content between varieties.
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Correlation between pigment contents and FRAP values in beet root (Beta vulgaris ssp. esculents var. rubra)
85-89.Views:269It is well known that beetroot quality is determined mainly by the red pigment content (betacyanins) and its uniformity of the root. The effect of the most important red pigment components (betanin). the total polyphenol content and antioxidants were studied in 20 beet root varieties. Antioxidants were expressed in FRAP (ferric reducing ability of plasma) values in pM/I.
Our results indicated a close correlation (r = 0.7799 and r = 0.7435. respectively) between betanin and total polyphenol contents of the root as well as between FRAP values.
Our measurements showed more than threefold differences in total antioxidant activity among varieties. the lowest value being 196.4 13M/1 and highest 702.57 pM/I. The corresponding betanin (16.3 and 57.8 mg/100 ml) and total polyphenol (37.5 and 85.5 mg/100 ml respectively) contents show similar differences. Based on our results it can be stated that varieties of higher betanin and poliphenol contents have higher antioxidant values as well.
Accordingly, the two compounds must have a role in the evolution of antioxidant effects.
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Sunburn assessment: A critical appraisal of methods and techniques for characterizing the damage to apple fruit
7-14.Views:342Many methods and techniques have been introduced for measuring alterations in the fruit and in its surrounding environment related to sunburn incidence. The research objectives, fruit materials and the environment to be evaluated dictate the methods to follow. These procedures are either non-destructive and involve techniques that allow us to track the course of sunburn development and related environmental parameters, or destructive and involve the removal of fruit from the tree for field/laboratory measurements. Techniques employed can be used for pre-symptomatic monitoring (before symptoms become visible) or characterizing the symptoms already present. The principles behind the measurements and their usefulness for sunburn assessments are discussed and critically evaluated in this review paper. Descriptions and evaluations of the methods and techniques were made in the following groups: 1. Thermal measurements; 2. Visual assessments; 3. Fruit quality measurements; 4. Measurements of physiological and biochemical alterations; and 5. Practical evaluation of sunburn damage. Thermal measurements involve methods tracking the ambient temperature and fruit surface temperature, and their relation to sunburn formation. Visual assessments cover all measuring techniques (skin color, chlorophyll fluorescence, radiation reflection, electron microscopy) that are able to detect changes on/in the fruit skin related to sunburn formation. Fruit quality measurements are used to point out differences in qualities (soluble solids, firmness, titratable acidity, and water content) between unaffected and sunburned areas of the fruit. The measurements of physiological and biochemical alterations (gas exchange, pigment analysis, enzyme activity, gene expression) give us a better insight to the mechanism of sunburn formation. Practical evaluations involve many procedures that are used by scientists to characterize the susceptibility of cultivars, evaluate protection technology, etc. For this purpose, the following methods are in use: expressing the percentage of the total fruit surface area affected by sunburn or the percentage of the total number of fruits damaged on the tree, or even a scale based on the severity of the symptoms occurred. All assessing methods and techniques described here have their pros and cons as well as their specific applicability, therefore any of these cannot be favored to use exclusively for assessing sunburn incidence. The combination of these techniques will be the best choice to meet a given research objective perfectly.
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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:420Beetroot 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.