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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:
    1293

    The 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.

  • Fruit Quality of Sweet Cherry Cultivars Grafted on Four Different Rootstocks
    59-62.
    Views:
    514

    A rootstock trial planted at the Szigetcsep experimental station in 1989 involved the study of two cultivars- `Germersdorfi FL 45' and 'Van' -grafted on four different rootstocks — 'Colt', `MxM 14 — Brokforest', `MxM 97 — Brokgrow' and 'Saint Lucie 64' as a control. The trees were trained to the "Modified Brunner-spindle" system and came into bearing in 1993. The yield per tree, fruit weight and fruit diameter have been measured each year since then. The refractivity, the acid content of the fruit juice, fruit cracking after four hours' dipping in water and stone weight ratio have also been measured since 1995. In 1997 and 1998 these parameters as well as fruit cracking after 24 hours' dipping were measured. Fruit firmness and fruit colour were also estimated. In almost every observed parameter significant differences were found between the scion cultivars. Yield efficiency was significantly higher on 'NUM 14' and 'Saint Lucie 64' than on the other two rootstocks. As regards fruit weight, in both cultivars and over an average of six years, it was found that trees on low yielding tree on 'Colt' rootstock had the highest fruit weight values and on heavy producing `MxM 14' the smallest. Soluble solids content was higher on 'Colt' and `MxM 97'. No significant differences between the rootstocks were found in acid content of the fruit juice. There were significant differences between the rootstocks in fruit cracking after 4 and 24 hours' dipping in water. Seemingly with respect to cultivars and rootstocks the year has a considerable effect on fruit cracking.

  • Phytoplasma diseases of grapevine and the possible measures to control them
    37-43.
    Views:
    637

    Phytoplasmas are a special group of phloem-living pathogens in several plant species. Grapevine yellows (GY) is a term for phytoplasma diseases occurring on Vitis vinifera and inducing the same or very similar symptoms and causing severe losses worldwide. Flavescence Dorée (16SrV) phytoplasma (FD, species name: ‘Candidatus Phytoplasma vitis’) is considered a quarantine pest in several countries due to its epidemic character and high economic loss it provokes. The leafhopper Scaphoideus titanus is the univoltine and monophagous vector of FD. Bois noir disease caused by stolbur (16SrXII-A) phytoplasma (species name: ‘Candidatus Phytoplasma solani’) is described under different disease names in different countries. Hyalesthes obsoletus (Cixiidae) is the only proved polyphagous vector of BN. However, distribution of BN disease is increasing also on those areas where H. obsoletus is not prevalent or only in a very low number. Therefore the presence of other vectors cannot be concluded. The ‘Tuf-a’ type Stolbur phytoplasma is associated with stinging nettle (Urtica dioica) and the tuf-b type one to field bindweed (Convolvulus arvensis). There are only preventive control measures against phytoplasmas: the use of pathogen-free propagating material, hot water treatment of propagating material, as well as control of vectors and weeds. S. titanus can be efficiently controlled by insecticide treatments. However, in case of H. obsoletus, insecticides are not effective due to the biological characters and feeding habits of the vector.Weed control can reduce H. obsoletus specimen and their abundance to a certain extent. Extensive research is needed on wild hosts of GY phytoplasmas especially on BN phytoplasma and its vectors to the better understanding of their epidemiology.

  • Effect of 1-MCP (1-methylcyclopropene) on the vase life of Chrysanthemum and Carnation cut flowers
    29-32.
    Views:
    432

    The effect of 1-MCP on extending the vase life of chrysanthemum and carnation cut flowers was studied. The flowering stems of both flowers were terminated to 50 cm. in height. Then, the flowers were pre-treated with 1-MCP at 0.3, 0.5 and 0.7g/m3 for 3 hours or 6 hours. The control flowers were placed in ambient air during the treatment. After the period of treatments the flowers were aerated then put in glass vials contained tap water. The vase life determination was conducted in a vase life evaluation room at 22 ± 1°C. Fresh weight determinations of the flowers were made just before the immersion of the flowers into the glasses of water and were repeated on the day when the vase life of the control flowers was terminated. The treatment of 1-MCP at 0.5g/m3 for 6 hours was the most effective treatment of chrysanthemum and carnation cut flowers.

  • Extending the vase life of Solidago canadensis cut flowers by using different chemical treatments
    83-86.
    Views:
    350

    In order to increase the vase life as well as quality of leaves of goldenrod (Solidago canadesis), the effect of 8-hydroxyquinoline sulphate (8-HQS), silver thiosulphate (STS) and l-methylcyclopropene (l-MCP) were investigated. 8-HQS was used as a continuous treatment at 400 ppm with or without sucrose at 50 g/l. The treatment of STS was used by putting the flower bases at 0.4 mM for 6h with or without sucrose at 50 g/l. l -MCP was used at 0.5 g/m3 for 6h dry or in water. Except the treatment of l -MCP in water, the chemical treatments, which were used, led to the increase vase of life of leaves as well as to the inflorescence of cut solidago spikes compared to the control. The best treatment in this concern was 8-HQS at 400 ppm without sucrose, which resulted in longest vase life of leaves as well as inflorescences and lowest percent loss of fresh weight of initial.

  • Spatial evaluation of the apple trees-soil environment
    53-56.
    Views:
    507

    Remote sensing of fruit tree micro environment plays a major role in both horticultural and soil mapping applications. In frame this study presented a novel method to survey the spatial distribution of physical and water management properties of soils. The examinations were carried out at an intensive experimental apple orchard in Debrecen-Pallag. The examination site is the part of the Experimental Pomology plantation of the University of Debrecen, Faculty of Agronomy. Particle-size distribution, plasticity according to Arany, metal content by XRF spectrometry, soil physical parameters, acidity, electric conductivity of soils, were measured to obtain appropriate information on the physical properties of the soil. Based on the results, the accurate spatial positions of those sites were characterized where soil loosening should be implemented in 0,3–0,4 m depth. Spatially precise soil physical barriers were determined for applied micro-irrigation system. Based on the micro-element content and pH, the accurate spatial positions of those sites were selected where melioration and micronutrient fertilization is needed. These detailed data sources also applied to calibrate the applied airborne hyperspectral images to extend spatially these point based information.

  • The effect of drying process on the pigment content and composition of table beet varieties
    115-117.
    Views:
    471

    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.

  • Cracking susceptibility of sour cherry (Prunus cerasus L.) in Hungary and relation to calcium application
    109-118.
    Views:
    839

    The rain induced fruit cracking is a big, serious problem especially for sour cherry growers but in some year sour cherry growers had also problem with fruit cracking caused by too much rainfall in the harvesting season. The cracked sour cherry fruits can be easily infected by different diseases like Monillinia sp. Cracked and infected fruits can not be transported for long distance and using for preservation because they lost their market value by the pour fruit quality. There are two possibilities to protect fruits against the rain induced fruit cracking. The most effective protection technique is the plastic rain cover over the tree rows. The installation of these equipments is too expensive for the growers. That is the reason why researchers tried to find other less expensive and sufficiently effective ways like sprayings different mineral salts, hormone and other type chemicals against the rain induced fruit cracking. Several calcium formulas calcium chloride (CaC12), calcium hydroxide (Ca (OH),) and calcium nitrate (Ca(NO3)2) can be sprayed in appropriate solution concentration.

    The aim of our trial is to determinate the fruit cracking susceptibility of wide grown Hungarian sour cherry varieties and find the most effective calcium formula and its concentration for spraying in orchards to prevent the fruit cracking. In the first trial year (2006) cracking index of tested sour cherry varieties were determined under field and laboratory conditions. Under field conditions were not found differences between cracking tendency of tested cultivars. After results of immersing fruits in distillated water for 24 hours tested sour cherry varieties were divided to three groups by the susceptibility to rain induced fruit cracking: very susceptible (`Maliga emléke', 'Piramis', 'Érdi jubileum', 'Erdi nagygyümölcsű’ and 'Meteor korai'); susceptible ‘Érdi bőtermő, Tandy 279' and Cigány 59.; moderately susceptible/tolerant ("T" and "R" clones). In the second trial year (2007) calcium chloride (CaCl2) and calcium nitrate (Ca(NO3)2) were sprayed in 0,35m/m%; 0,5m/m% and 1,0m/m% solution concentration. One more commercial product "Damisol-Kalcium" was also applied in the advised 1,0m/m% concentration. Like in the trial year before (2006) under field conditions we did not kept differences between the cracking susceptibility of varieties and calcium treatments. As the result of laboratory testing (immersing calcium treated fruits in distillated water) we kept that calcium chloride (CaCl2) seems the most effective against the fruit cracking in 0,5m/in% solution concentration. The other calcium formulas also decreased the cracking ratio but in less scale.

  • Prolonging the vase life of cut Carnation 'GIOKO' by using different chemicals
    65-68.
    Views:
    464

    Cut flowers of Dianthus caryophyllus L. cv. GIOKO were treated with different concentrations of sucrose and in combination with 1­methylcyclopropene (1-MCP) to compare the effect of these treatments with floral preservative (`Spring') on the longevity of flowers. Distilled water was used for preparing all solutions. The control flowers were held in distilled water. Clorox at 2 mL- I was added to all treatments containing sucrose and it was also applied as a separate treatment. The vase life of cut carnations was significantly prolonged due to the use of chemical treatments, as compared to the untreated control. The longest vase life (18.33 days) was obtained by using 1-MCP 0.5 g m-3 for 6 h treatment. All concentrations of sucrose had a positive effect on flower diameter. The best treatment in this respect was 1 -MCP with 30 gL-I sucrose. 1-MCP treatment significantly increased the chlorophyll content, as compared to the control or the "Spring" treatment. The highest values in this respect were obtained by 1 -MCP treatment alone or with the lowest level of sucrose. The effect of these treatments on the pH of solutions is discussed.

  • Commercial varieties of European plums grown in Hungary, a comparison of promising foreign varieties with the widely grown traditional ones
    15-22.
    Views:
    641

    Observations and investigations performed in laboratory at several growing sites over a period of many years are summarised on established plum varieties as well as on new promising ones concerning their marketing value. The ripening period of plum varieties was enlarged substantially with the appearance of new varieties of extra late maturity (‘Elena’, ‘Tophit’, ‘Presenta’). The new varieties did not alter the traditional colour, more or less long, violet or blue character of the plum. The most known type, ‘Besztercei szilva’ with its accustomed taste was followed by the new varieties ‘Katinka’, ‘Tegera‘, ‘Hanita’ and ‘Presenta’. The fruit size are largely of the medium category, except the early ripening small ‘Katinka’, whereas the larger and attractive (~60 g) fruits are represented by the late ripening ‘Tophit’ and ‘Empress’. The stone/fruit ratio was lowest in 3% (‘Tophit’) and 6% (‘Besztercei Bt. 2’, ‘Hanita’, ‘Jojo’, ‘ ‘Čačanska rana’) at the other end of the scale. The width and thickness of the fruit fl esh between 28 mm (‘Besztercei szilva’) and 43-44 mm (‘Empress’, ‘Tophit’). The fi rmness of the fruit fl esh excelled in the late maturity varieties ‘Presenta’ and ‘Tophit’ (~4 kg/cm2). Water soluble solids were 12-13 Brix% (‘Čačanska rana’, ‘Katinka’, ‘Silvia’) and 20 Brix% (‘Presenta’, ‘Tophit’), whereas titrated acids are found between 0.2% (‘Besztercei Bt. 2’) and 1.2% (‘Tegera’).

  • Relation of sour cherry blooming dynamics and meteorological variables
    17-23.
    Views:
    1535

    The aim of our research was to identify the role of weather parameters in the development of the start date and length of blooming. In order to achieve this, we examined how meteorological conditions of a particular year influence the start date and length of blooming in different years (dry, wet, cool, hot, sunny, cloudy). The meteorological parameters were the following: maximum temperature, minimum temperature, average temperature, precipitation, length of sunlight, difference of daytime and nightime temperatures, potential evaporation-PET, Huglin-index,Winkler-index, climatic water balance which can be calculated as a difference of precipitation and potential evaporation. In this study we wanted to find out whether early start of blooming results in a longer blooming period or if there is a generally faster blooming period when blooming starts later. Based on the results we can say that early start of blooming resulted in extended blooming period for three sour cherry varieties at the examined production sites. The start of blooming showed the closest relation with the difference of average daytime and nightime temperatures of the 30-day period prior to blooming. Significant relation was also detected with the thermic indexes as well as with maximum temperatures, climatic water balance and the degree of potential evaporation.We examined how weather 30 days prior and during blooming influenced the length of phases. Results showed that precipitation prior and during blooming is in significant relation with the length of blooming. We detected significant relation between daytime and nightime temperature differences and the length of blooming. The nature of the relation indicates that blooming periods were shorter in case of increasing temperature differences.We found that shorter blooming lengths occurred when maximum temperatures averaged between 13.5–14.5 ºC 30 days prior to blooming when examining the relation between blooming length and maximum temperature. If the average of maximum temperatures was below 13 ºC or exceeded 15 ºC during this period, then we could calculate with a blooming period longer than ten days. We proved that little precipitation and high temperature accelerates physiological processes, therefore we could calculate with an accelerated blooming and shorter blooming period.

  • Study of Erwinia amylovora colonization and migration on blossoms of susceptible and tolerant apple cultivars
    15-19.
    Views:
    363

    The stigmata of detached flowers of susceptible and tolerant apple cultivars were inoculated with about 104 gfp labeled Erwinia amylovora . There were no apparent differences in the colonization, multiplication and survival of the bacteria on the stigmatic surface of the culivars. Bacteria were washed down to the hypanthium surface 24 hours after inoculation. The visual symptoms of the infection were the discoloration and shrinkage of the floral parts. The gradual browning associated with the infection appeared first on the surface of the hypanthium followed by the discoloration of the style. The color of the filaments turned into brown only 120 hours after the inoculation. Bacterial cells were not detected in the tissues of the styles and filaments. The traits of the hypanthium surface are of prominent importance in the progression of the infection. The wrinkled surface, the convex shape of the outer epidermal cell walls with thin cuticle and the sunken stomata helped to preserve a water film for a longer period providing medium for the motility of the bacteria in the susceptible cultivar. Bacteria were restricted to small water droplets on the flat and waxy surface of the hypanthium of the tolerant cultivar and only a few were able to enter the tissues.

    Large bacterium aggregations were detected in the intercellular spaces of the parenchyma of the susceptible cultivar 48 hours after the inoculation. In the next period the Erwinia amylovora cells gradually invaded the intercellulars of the hypanthium wall, the wall of the ovary and the pedicel. Low level of bacterium aggregation was found in the intercellulars of the tolerant cultivars. It is suggested that the progression of the infection was inhibited also by physiological factors.

  • Effects of nitrogen fertilizer application rate and time to first harvest on leaf area index; leaf nitrate content and yield of irrigated leaf rape (Brassica napus L. var. Giant)
    64-75.
    Views:
    544

    In Zimbabwe, smallholder cultivation of leaf rape is of considerable importance due to the increasing demand for the leaf vegetable from the rapidly increasing urban populations.  A two-season field trial was conducted in the Agricultural Practice Experimental Plots of the Midlands State University in central Zimbabwe. The objective of the study was to establish selected biometric responses of leaf rape to N fertilizer rates and time to first harvesting. Increasing the rate of N fertilizer application considerably improves the yield of fresh rape leaf; LAI and concentration of leaf nitrate. Delaying rape leaf harvest after N fertilizer side dressing can be used as a strategy to boost rape leaf yield for vegetable markets with high single delivery demand. When harvesting is deliberately delayed after N fertilizer application rape LAI are significantly increased. Delaying the first leaf harvests by 7; 14 and 21 days after N fertilizer side dressing amendments increases the content of nitrate in fresh rape leaves. Fresh rape yield can be more accurately predicted by values of rape LAI. Nitrate concentrations in fresh rape leaf is a poor predictor of rape yield under field conditions.

  • Changing of inert content values of apricot varieties
    39-41.
    Views:
    612

    The 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.

  • Anatomical study of the bud union in „Chip" and „T" budded 'Jonagold' apple trees on MM 106 rootstock
    27-29.
    Views:
    876

    The traditional methods for vegetative propagation of apple and its varieties are the T-budding, and the winter grafting, but this latter way is a difficult and expensive procedure.

    In our experiment carried out in the Fruit Tree Nursery Soroksár, the healing process of chip- and T-budded apple trees 'Jonagold' on MM 106 rootstock was studied.

    The budding (T- and Chip-) was made in the first week of August, samples for microscope examination were taken monthly after this time until leaf fall.

    The investigated part of plants was made soft with 48 % HF (hydrogenfluoride), then cross and longitudinal section were made and examined by microscope.

    Based on analysis of microscope pictures in case of Chip-budding, it was established, that development had started quickly after budding on the rootstock and scion too. But the callus originated almost entirely from the rootstock tissue as new parenchyma cells fills the gap between the two components of graft (scion and stock), becoming interlocked and allowing for some passage of water and nutrients between the stock and the scion. This quantity of callus in case of T budding was under the scion buds larger, than the Chip-budded unions, where the thickness of callus mass is uniformly thick round the chip. The large mass of callus pushes the scion bud outwards from the shoot axis, which later results in a larger shoot-curvature above the bud union.

    Following this process on the Chip-budding it can be observed also, that a continuity of the cambium is established between bud and rootstock. Then the newly formed cambium started typical cambial activity, forming new xylem and phloem.

    Later the callus begins to lignify, and it is completed within about 3 months after budding.

     

  • Pedological and agrochemical investigations on media using in vegetable forcing
    119-122.
    Views:
    223

    In spite of the several good properties of peat, recently, some experiments were carried out with the aim of finding natural materials which can substitute for peat. According to the results, several inorganic and organic materials were proved to be suitable for this purpose. This study examines the effect of different organic materials (example: pine bark, composts, peats) on the growth and yield of green pepper (Capsicum annuum L., variety Danubia). We found that the most developed plants were grown in peat-mixtures and pine bark. The average fruit weight was the highest at those plants which were planted also in these media. The plants which were grown in composts fell short of our expectations in development and in yield, too.

  • Work quality assessment of a cherry sorting machine
    57-62.
    Views:
    1439

    The conditions of the cultivation of marketable cherries are diverse. Choosing the production site on the basis of the climatic conditions, selecting the most appropriate variety taking into account the region and the purpose of the production, utilization of the optimal production method, to ensure the required water and nutrients supply, frost and hail protection techniques, modern technology in crop protection, and professional performance of harvesting and handling, to name just a few of the most important issues. The objective of present study is to determine the qualitative characteristics of the UNITEC cherry sorting machine.

  • The hydroculture of calla
    90-92.
    Views:
    248

    Hydroculture was established in the early 40's. This technology became wide-spread in 60's. Because of economic considerations it played little role in Hungarian ornamental plant growing. The forthcoming joining of the EEC as well as the strict enviroment protection regulations, this technology is likely to spread in our country and like in most of the West European countries, cut flowers will be grown in hydroculture. Closed systems match the most strict environmental regulations. Calla can be well adopted to this technology because of its origin and water demand.

    We have studied three growing methods: PUR-agrofoam, container and soil-heated, of which soil-heated proved to be the best significantly.

  • Impact of substrate supplemented with CaCO3 on mycelial growth, yield, morphological features and storability of fruiting bodies of black poplar mushroom Agrocybe cylindracea (DC.) Marie.
    76-86.
    Views:
    1080

    Black poplar mushroom, Agrocybe cylindracea deserves special attention, due to its medicinal properties. Water and alcohol extracts from fruiting bodies of the fungus have an anti-oxidant, anti-cancer, anti-fungal, cholesterol and triglycerides blood level lowering abilities. This mushroom is rich in proteins and vitamins, mineral elements and low in fat. The aim of the experiments was to determine effect of a substrate supplementation with CaCO3 on mycelial growth, yield, morphological features and storability of fruiting bodies of four strains of A. cylindracea (DC.) Marie. The amount of additive to sawdust substrate affects rate of mycelial growth and yield of investigated strains. A. cylindracea mycelial growth was not affected by addition of CaCO3 to substrate, however a significant effect of this additive was found on yield, which was the highest with CaCO3 addition in an amount of 8 g/100 g of substrate. Carpophores characterized with the largest caps diameter, and the largest individual mass obtained of substrate enriched with CaCO3 addition of 8 g/100 g of substrate. In addition, it was found that supplementation with CaCO3 affect storability of A. cylindracea. The lowest weight loss of fruiting bodies after 3 and 7 days of storage was found with addition of CaCO3 to substrate in an amount of 4 g/100 g of substrate.

  • Effect of basal and foliar application of boron and zinc on yield attributes in Solanum melongena L.
    97-99.
    Views:
    288

    Field experiments were conducted during 1999-2000 and 2000-2001 to study the effect of basal application (BA) of zinc sulphate (5 and 10 mg kg-i soil) or boric acid (1 and 2 mg kg-1 soil) alone or foliar applications (FA) of water or 1% ZnSO4 or 1% H3 B03 or the combinations of both BA and FA of either ZnSO4 or H3 B03 on yield attributes (number of flowers and fruits/ plant, fruit weight, size and total yield). On the basis of the two-year data, it was found that all the treatments of BA as well as FA enhanced yield attributes but the combination of BA of 10 mg kg--1 soil ZnSO4 and FA of 1% H3 B03 gave highest yield as compared to other treatments and control plants.

  • Differing effects of grass and polythene mulches on sweet potato productivity in derived savannah agro-ecology
    24-30.
    Views:
    504

    Sweet potato as a food crop that is grown for both its tuberous roots and vegetative parts, the latter of which also serves as animal feed. Its production in the savanna regions can be limited by high evaporative demand, especially where soils with low water retentivity are involved. This work studied the effects of various locally available polythene as mulch materials for sweet potato growth in derived savanna agro-ecology. An experiment was thus conducted at Nsukka, a derived savannah in southeastern Nigeria, with orange fleshed variety of sweet potato. Treatments were polythene mulches of contrasting colours (black, white, red and blue polyethylene), including also organic mulch (dry grasses) as reference and a no-mulch control. The experiment was executed in two successive cropping seasons, and the data averaged and analysed. Agronomic and weed incidence data collection was done fortnightly from 2nd to 10th week of planting. The results showed that the polythene mulches (especially the black one) were better in the control of weeds. Furthermore, the sweet potato yields were affected significantly (p < 0.05) by mulching on the total number of tubers for each plant with grass-mulched plots showing the highest value (36) and transparent polyethylene-mulched plots the lowest (19). Also, total weight of tubers per plant at harvest differed (p < 0.05), with grass-mulched plots showing the highest value (2.39 kg), followed by the control (no mulching) plots (1.62 kg), then the coloured polyethylene mulched plots with the red polyethylene-mulched plots as the lowest (0.64 kg). This study recommends the use of organic mulch or no mulching in sweet potato production in this agro-ecological zone as they produced the best yields.

  • Sunburn assessment: A critical appraisal of methods and techniques for characterizing the damage to apple fruit
    7-14.
    Views:
    886

    Many 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.

  • Foliar application of zinc and its effect on greenhouse grown cucumber
    79-82.
    Views:
    693

    The 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.

  • Evaluation of morphological parameters and bioactive compounds in different varieties of beetroot (Beta vulgaris L. ssp. esculenta GURKE var. rubra L.)
    31-35.
    Views:
    910

    Beetroot 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.

  • Concentration of ‘Oblachinska’ sour cherry juice using osmotic distillation
    31-34.
    Views:
    1562

    Sour cherry is one of the most famous and characteristic Hungarian fruit what is also commonly used in food production as a colour additive. The sour cherry cultivar, ‘Oblachinska’ was shown to be a rich source of antioxidant compounds, including mainly anthocyanins. Valuable compounds in fruit juice – vitamins, polyphyenols etc. –are heat-sensitive molecules, which should be taken into account during the process of concentration to prevent degradation. Osmotic distillation seems a suitable option to product high quality sour cherry juice because this process does not require high temperature or pressure. Raw juice with approximately 15°Brix was used for the experiment and tried to concentrate up to 60° Brix where the water activity low enough to inhibit the microbiological deterioration. Before and after the process, TPC (total phenolic compounds) and FRAP (ferric reducing antioxidant power) was measured using spectrophotometric methods to determine the effect of the osmotic distillation. Our results point out that osmotic distillation is a promising method to concentrate sour cherry juice and prevent the loss of valuable compounds.

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