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  • Comparative Study of Dutch and Hungarian Environmentally-friendly Apple Orchards on Potential Ascospore Dose of Apple Scab
    31-36
    Views:
    105

    In a 2-year study, Dutch and Hungarian environmentally-friendly apple orchards were compared as regards the amount of apple scab primary inoculum. The PAD (potential ascospore dose) method was used to quantify the potential amount of primary inoculum (ascospores) per m2 orchard floor. Applying this method, the number of lesions per m2 of leaf in the autumn (LD), the proportion of the orchard floor covered by leaf litter at bud break (LLD) and potential ascospore dose (PAD) were determined. In autumn, LD values ranged between 2.2 and 13.5 in the integrated orchards, while in the organic orchards the values were between 42.5 and 106.2, with especially high values in the Dutch organic orchard. LLD values ranged between 24 and 43% at bud break in both countries. PAD values were 10-60 times higher than those of the integrated orchards. The PAD values were between 673 and 4275 ascospore/m2 orchard floor in the integrated orchards, while in the organic orchards these values were 37102 and 52390 ascospore/m2 orchard floor, respectively. On the basis of the recorded primary inoculum quantity, the Dutch integrated apple orchard is considered to be excellently protected, while the Hungarian orchard has a medium level of protection. However, both countries’ organic orchards can be regarded overall as being very poorly protected. Accordingly, in the integrated orchards the predicted epidemic risk is low or medium, while in the organic orchards it is very high on the basis of PAD values.

  • Comparison of Integrated and Conventional Production of Young Nonbearing Apple Orchards
    3-5
    Views:
    90

    The large number of pesticide applications in apple orchards creates serious problems with pesticide residues and their side effects on beneficial organisms, the environment and human health. This is the reason behind the search for new systems for apple protection.
    The investigations were made in apple orchards of the Institute of Agriculture at Kyustendil, during the period from 1997-1999. Three scab resistant cultivars grafted on rootstocks MM106 were planted in 1996. The orchard was divided into four plots. Two plots were treated as „conventionally” and the other two were treated as „integrated” according to the general principles, rules and standards of integrated apple production.
    The key disease during the experimental period was powdery mildew, which can be controlled only with pruning of infected clusters and shoots during the first three years after planting. The key pests in the orchard during the nonbearing period were the green apple aphid and San Jose scale. In the integrated plant protection system, it is possible to reduce the number of insecticide treatments depending on the density of the main pests.

  • Effects of different groundcover matters on nutrient availability in an integrated apple orchard in Eastern-Hungary
    21-25
    Views:
    120

    The aim of our study is to examine the effects of different groundcover methods on nutrient availability and uptake of apple orchard. The
    experiment was carried out at the orchard of TEDEJ Rt. at Hajdúnánás-Tedej, in Eastern Hungary. The orchard was set up on lowland chernozem soil in the Nyírség region. It was established in the autumn of 1999, using Idared cultivar grafted on MM106 rootstocks at a spacing of 3.8 x 1.1 m.
    The applied treatments were divided into two groups according to origins and effects. On the one hand, different livestock manures (cow,
    horse and pig), on the other hand different mulch-matters (straw, pine bark mulch, black foil) were used. The different manures and mulches
    were applied on the surface to test the effectiveness of these materials.
    The effectiveness of manure treatments was higher than the other treatments on AL soluble P content of soil. Mostly the manure treatments
    increased the AL soluble K of soil. Our all treatments increased 0.01 M CaCl2 soluble NO3 - -N content of the examined soil layers. The effect
    of manure treatments was the highest. From the results it was evident that the amount of easily soluble organic nitrogen fraction distributed
    more homogeneously than the other mineral N fractions examined.
    Our results can be summarized as follows:
    1. Our results pointed out that the used ground covering matters divided into several categories regarding its effect.
    2. The available N, P and K contents of soil were mostly increased by applying manures.
    3. The effectiveness of straw, mulch and mostly black foil was lower.
    4. Differences were found between nutrient supplying treatments and the treatments which did not supply nutrients.

  • Loss and Disease Development of Monilinia fructigena (Aderh. & Ruhl.) Honey in an Organic Apple Orchard
    6-8
    Views:
    219

    In a two-year-study, yield loss and temporal development of incidence of Monilinia fructigena were quantified in organic apple orchards and the importance of fruit wounding agents was determined. The first infected fruits were observed at the beginning of August in 2001 and 2002. Disease development was continuous until fruit harvest in both years. Pre-harvest yield loss caused by Monilinia fructigena amounted on average 27.2% in 2001 and 41.6% in 2002 by fruit harvest. The growth rate of disease development was almost double in 2002 compared to 2001. All infected fruits were injured by wounding agents such as aboitic and mechanical injury factors, codling moth (Cydia pomonella), common earwig (Forficula auricularia) and birds. In this study, the most important wounding agents were codling moth and mechanical injury factors in organic apple orchards. In both years, our results showed that 70-80% of the infected fruits were damaged by codling moth in organic apple production. Moreover, 10-15% of the infected fruits were mechanically injured in the two years. Our results indicated that most of the damaged fruits fell on the orchard floor before harvest and they became an important secondary inoculum source of M. fructigena. Biological and practical implications of the results are discussed.

  • Preliminary studies to evaluate the use of spectral data in monitoring of apple orchard parameters
    37-41
    Views:
    140

    The introduction/application of precision agricultural technologies has more important role in various fruit growing sectors among others apple growing. Remote sensing methods can detect electromagnetic waves where the green colour of the leaf is responsible for the chlorophyll content. The absorption of chlorophyll is in the wavelength range of 450–670 nm. Samples of apple tree leaves were taken on a weekly basis from the apple orchard at Horticultural Unit of Pallag on University of Debrecen in 2019 summer. Our studies were performed on 2 cultivars (Early Gold, Golden Reinders) and the samples were processed using 2 methodologies: a non-destructive spectral method and spectrophotometric method chlorophyll and carotenoid contents were calculated, which were created into some groups and compared with the spectral values. When the plant begins to lose strong green colour and turns yellow spectral measurements show that chlorophyll content decreases as the proportion of chlorophyll-carotenoid in the plant changes.  In case of grouping into intervals, it can be observed that as the chlorophyll content increases the reflectance value decreases continuously due to the strong absorption. Based on the results, close relationship between the pigments can be detected.

  • Effect of Ozone Exposure on Phytopathogenic Microorganisms on Stored Apples
    9-13
    Views:
    118

    The aim of our study was to clarify the effect of ozone exposure on several phytopathogenic fungi on stored apple fruits under different storage conditions. The study was conducted at Bistrita, Romania, in the storehouse of an experimental apple orchard in 2002 and 2003. Two widely grown apple cultivars (‘Jonathan’ and ‘Golden Delicious’) were used. General microbial examination of the fruits was made during storage in order to identify the most important storage pathogens. Efficacy of six ozone treatments was evaluted on fruit decay caused by phytopathogenic fungi. Monthly observations (January, February, March and April) were made of the degree of decay and three measurements were assessed (disease frequency, disease intensity and degree of attack). Our results showed that the most important phytopathogenic fungi during storage was blue mold, caused by species of Penicillium. Disease frequency of apple fruits was very high on cv. ‘Jonathan’, much higher than on cv. ‘Golden delicious’. Ozone treatments (25 ppm ozone for 0.5 and 1.5 hours in November) caused significantly lower disease incidence on stored apple than all other ozone treatments. For longer storage, it seems that additional ozone treatments in February increased treatment efficacy. Cv. ‘Golden delicious’ seemed to be more resistant to storage diseases than cv. ‘Jonathan’ both on the untreated and treated fruits. The effect of the ozone treatments was also the most effective when 25 ppm ozone was applied for 0.5 and 1.5 hours in November.

  • Composition and role of hoverfly (Diptera: Syrphidae) communities in an organic apple orchard
    57-61
    Views:
    126

    The use of hoverfly (Syrphidae) larvae in biological control is gaining more attention where the damage by their prey, aphids is  significant, especially in agricultural fields and orchards, where they lower the number of aphids. The present study focuses on one hand on faunistics, on the other hand on testing the different available collecting methods for later research. Collecting in an organic apple orchard near Debrecen yielded 525 specimens of Syrphidae mostly by netting but also with white tray traps. Collected species are differentiated according to their feeding (94.1% aphidophagous). The three species found in greatest numbers are Sphaerophoria scripta (Linnaeus, 1758), Melanostoma mellinum (Linnaeus, 1758) and Episyrphus balteatus (De Geer, 1776). The available information on their biology is reviewed and their potential value of hoverflies in biological control is discussed.

  • Effect of hail net on the water potential of an apple orchard
    109-113
    Views:
    179

     Apple production has seen a decline in yields in recent years, primarily due to ecological factors such as drought, water stress, water scarcity, uneven rainfall distribution, frost damage and hail damage. Ecological factors that are harmful to the plant can be eliminated by human intervention, irrigation or the use of hail net. In our study, we investigated the positive effects of hail net on the development of plant water potential as the vegetation progressed, in non-irrigation area with temperature and humidity. Water potential values were determined using a field osmometer. Confirmed the positive effect of the ice protection net in the apple orchard of Early Gold and Golden Reinders. Our results were supported by statistical analyzes our results.

  • Quality comparison of selected apple cultivars under ULO-storage
    62-75
    Views:
    102

    Our examination was carried out in the 103 ha apple orchard of the Kasz-Coop Ltd.. The plantation works with modern varieties standing on M9 root stock, planted in a tree density of 2500 tree/ha and treated with professional integrated technology. The date of harvest is defined by a combination of several ripening analyses methods. The orchard has its own ULO-system warehouse.
    Used in the experiment were four apple varieties: ’Idared’, ’Golden Reinders’, ’Jonagold’ and ’Braeburn’.
    While under ULO-storage, we took 20-25 piece samples 6 times regarding the four varieties, from which 5-5 pieces were kept under three weeks’ shelf life, measured on a weekly bases. In our research, we analysed the dynamics of the flesh firmness and the refractometric value under ULO-storage and three weeks’ shelf life, and the standard deviation dynamics of the refractometric value under ULO-storage.
    Analyses were based on the following measurements: flesh firmness, refractometric value and number of mature seeds.
    We looked for morphological and morphological-quality correlations.
    Through these we described the dynamics of the flesh firmness and the refractometric value under ULO-storage and three weeks’ shelf life for each variety. We referred to the stability of these attributes and to the dynamics of their change. Later, with the help of these, and also considering our practical experience related to the measurements, we characterised the four varieties.
    We found a positive correlation between the seed number and the flesh firmness in the case of the ‘Idared’, ‘Jonagold’ and ‘Braeburn’ varieties, but no correlation was found in the case of ‘Golden Reinders’ in this concern. We visualized the standard deviation dynamics of the refractometric values under ULO-storage. This allowed us to categorise the varieties.

  • Effects of soil compost application on the leaf surface area per running meter of apple (Malus domesticaBorkh.) leaves cultivated in organic and integrated orchard
    111-116
    Views:
    157

    The effect of different compost doses on the nutrient contents of the soil (in depth of 0–30) were measured in an (organic and integrated) apple orchards. The leaf surface area per running meter shoot for certain apple species (Golden Delicious and Pinova) were determined.

    The field experiments were conducted in the Research Field of Debrecen-Pallag, University of Debrecen, the analysis of the soil and plant samples took place in the laboratories of the Institute of Agricultural Chemistry and Soil Science.
    The compost treatments increased the amount of the examined nutrients in the top 30 cm of soil originated from organic and integrated orchard. Changes in rainfall were observed in the trends of the leaf surface area of the two apple varieties. 2010 was rainy and 2012 was drier. The leaf surface area of the Pinova increased better under the precipitation/year effect, than in case of the nutrient supply treatments. The opposite was observed in case of the Golden Delicious.

  • Nutrient Supply Effects on the Fruit Quality of Apple (Malus domestica Borkh.)
    230-235
    Views:
    125

    The aim of our two year study is to research the effect of nutrient supply on apple fruit quality, and to explore the relationships between selected fruit quality parameters.
    Observations were made in Kálmánháza (in the eastern part of Hungary), on a commercial apple orchard. In this experiment, we studied the nutrient supply reaction of four apple cultivars (Golden Delicious, Granny Smith, Idared and Jonathan Csány) under different N and NPK doses. The following fruit quality parameters were studied: fruit diameter, fruit height, fruit weight, flesh firmness, colour-coverage and we studied the density of foliage.
    The research results showed that N fertilization has a great effect on fruit quality. This is shown in the cases of increase of fruit size (fruit diameter, fruit height, fruit weight). The increase is proportional with the N doses, accordingly the highest positive difference was observed by using 100 kg/ha N doses. It is important to note that moderate N doses (75 kg/ha) plus P and K additions also had positive effects. There approached the values of 100 kg/ha N, and even exceeded its values in the cultivar Golden Reinders. The increased N doses enlarged the standard deviation, on the other hand, this parameter was low in the cases of balanced NPK fertilization. The nutrient supply increased the vegetative area (density of foliage) in addition to the generative parts, in particular only N fertilizer. However the denser foliage hindered the growth of fruit weight and colour-coverage, and also decreased the fruit quality and the flesh firmness of cultivars, which have a negative effect on storageability.
    A linear correlation was demonstrated between the fruit weight and colour-coverage, or between fruit weight and flesh firmness. The character of their relationship was similar, but the direction differed: high fruit weight was with high colour-coverage, but with low flesh firmness.

  • Effects of fermented and supplemented chicken manure on the nutrient management aspects of an apple orchard
    117-123
    Views:
    155

    AIt is a huge challenge for farmers worldwide to successfully increase the organic matter content of their soils and improve their water balance at the same time. Therefore, the main aim of the study is to develop and test organic-based nutrient composite materials that can be successfully used by farmers to increase soil organic matter content, improve water management parameters and implement water-efficient technologies. The study was performed in the orchard of the Institute of Horticultural Science of the University of Debrecen in Hungary (Debrecen-Pallag). The experiment was set up in a ten-year-old apple (Malus domestica ‘Pinova’) orchard. In the trial, fermented poultry manure and superabsorbent polymers (SAP) were used at different doses to study their effects on soil properties and fruit quality. Applied composite materials increased the nitrate and organic nitrogen content of the soil. Treatments did not affect the sugar content of the fruits but significantly and positively affected the individual fruit weight and the titratable acidity of the fruits.

  • Spectral analysis of stress symptoms caused by apple powdery mildew (Podosphaera leucotricha
    83-88
    Views:
    243

    An orchard can be examined on the basis of spectral data, using methods with which the reflected radiation can be divided into a large number of (several hundreds) small spectral channel (some nm). Calculated on the basis of such hyperspectral data from different index numbers the water supply of foliage conditions can be well characterized.

    The research site is an intensive apple orchard, which located in University of Debrecen, Agricultural Sciences Centre, Farm and Regional Research Institute at Pallag. During my experiments the preliminary evaluation of spectral, non-invasive measurement method are carried out for detecting stress symptoms caused by Podosphaera leucotricha.

    Based on the results narrow band greenness indices (NDVI705, mNDVI705, mSR705 and REP) can be used for determination of diseased canopy and for the detection of stress symptoms of Podosphaera leucotricha,. These statements can be utilized in precision plant protection systems, since it can be a basis for such integrated active sensors with LED or laser light source, measuring reflectance at the certain spectral range, which can facilitate real time status assessment of orchards and can control precision fungicide utilization.

  • Effect of Rootstocks on Blooming Capacity and Productivity of AppleCultivars
    14-20
    Views:
    143

    The experiment with three different rootstock cultivars was set up in a commercial apple orchard at Nagykutas, which is situated in the western part of Hungary. The aim of our two-year-study was to determine the effect three different growing rootstock cultivars (M9, MM106 and seedling) on the flowering and productivity of 33 apple cultivars. Our observations included the following measurements: the date of the beginning and the end of flowering, flower density, fruit density, fruit numbers per tree and tree productivity. According to our results, it was found that the different growing rootstocks have a great determining effect on the above measurements. Our results showed that the flowering period was similar for all cultivars on the three different rootstocks. However, the flowering and the fruit setting decreased in the order M9, MM106 and seedling rootstocks. In contrast, the fruit number per tree followed, in decreasing order, MM106, seedling and M9 rootstocks.

  • Effect of M9, MM106 and Seedling Rootstocks on Sunburn-Sensitivity of 33 Apple Cultivars, and Sunburn Effects on Fruit Quality
    236-247
    Views:
    99

    The purpose of this study was to investigate the sunburn-sensitivity of 33 apple cultivars grafted onto 3 rootstocks (M9, MM106 and seedling) in a commercial orchard at Nagykutas (in the western part of Hungary). The authors also searched for any relationship between fruit quality parameters and the frequency of sunburn on the fruit surface.
    During the observations, the cultivars had rootstock-specific properties in respect to sunburn-susceptibility. Accordingly, the injury decreased in the order M9, MM106 and seedling rootstocks. The differences in the sensitivity were founded on the foliage-morphological characteristics of trees, caused by the growing vigour of the rootstocks. Accordingly, the highest value of sunburn injury was observed on M9 rootstock, because this rootstock has a dwarfing effect on the grafted main cultivars. Thus, the vegetative area of these trees grew very slowly and the foliage was not compact enough to protect the fruits from the strong rays. The largeness and density of the foliage increased in the order M9, MM106 and seedling rootstocks. Relationships were also demonstrated between the diameter of the upper part of crown, the size of leaves, the number of fruits per tree and the injury from sunburn.
    The damage values showed, that the gravity of symptoms did not decrease below a well-defined level of dimension on fruit. Determined potential area of injury was necessary for the symptoms to become visible.
    The authors categorized the cultivars in the respect of values of sunburn frequency: I. „Not sensitive”, II. „Moderately sensitive” and III. „Very sensitive” categories were constituted. Generally, the Gala cultivars showed low damage (or were free of symptoms), in contrast, Golden mutants suffered relative strongly. The most sensitive cultivar was Jonica on all three of rootstocks.
    We searched for any relationship between the fruit quality parameters and the frequency of sunburn. A significant correlation was found in the cases of fruit weight and colour-coverage. The latter can be related to that fact that highly colour covered fruits are found on the peripherial part of crown, so these are exposed to stronger sun rays

  • Early evaluation of use of fermented chicken manure products in practice of apple nutrient management
    195-198
    Views:
    186

    According to the Green Deal efforts, the importance and relevance of organic fertilization will increase in the near future. Therefore, the investigation of the effects of different organic fertilizers on soil productivity and nutrient supply is a priority area of agricultural research. Organic fertilizer experiment was conducted in an eight-year-old apple (Malus domestica Borkh.) orchard at Debrecen-Pallag. In the trial Pinova cultivar was used. In this study, two different fermented chicken manure products were added to the soil (in 20 cm depth) to test their effects on soil nutrient status, plant uptake and fruit quality. It was found that the applied treatments slightly increased the pH and nutrient levels in almost all cases, but significant effect was not observed in all treatments compared to the control. Leaf nutrient contents (N, P, K, Ca and Mg) were measured in the experiment. Leaf nutrient status was not affected by the fermented chicken manure treatments. However, used treatments had strong effects on the fruit characteristics and inner parameters, such as fruit diameter and Brix value. Moreover, it was established that the applied organic fertilizers increased the yield significantly.

  • Application of advanced environmental assessment methods in orchard management
    221-225
    Views:
    157

    Our reseaches were carried out in apple and pear orchards at Farm and Regional Research Institute in Pallag of the University of Debrecen and Pear Gene Reservoir in Újfehértó. Aim of this study is to interpret and analyse field studies with the aim of a GIS based database. Furthermore, beside field measurements, airborne and field hyperspectraldatacollection and analysis were also made to facilitate special watermanagement and irrigation related surveys. The integration of unified, geoinformatics systems with high spatial resolution and calibrated airborne hyperspectral data are appropriate tool for decision support systems, which support the continuous update and actualization of the changing cropping data, the analysis of cropping results in a unified complex data system, the acquiring of agro environmental subsidies, the establishment of monitoring system, and the optimization of irrigated fruit production.

  • Applicability of precision weed detection technologies
    163-168
    Views:
    224

    In an agricultural field or horticultural plantation, weeds compete with cultivated plants for water and nutrients. The transpirated water by the weeds is needed to be replaced, which saddles surplus costs on the farmer, which could reduce the profitability of crop production. The aim of the precision plant protection system is to protect cultivated plants by applying site-specific technologies and optimized herbicides combination and methods, without environmental damage. The first step of precision weed control is the scouting for weeds. Traditional and modern (passive and active remote sensing) weed surveying technologies are available to detect weeds. The examination was carried out in an intensive apple orchard with drip irrigation system, protected by hail net of the Study and Regional Research Farm of the University of Debrecen near Pallag. The spectral-based weed detection was worked out by the Tetracam ADC broadband multispectral camera and the GreenSeeker 505 vegetation indexmeter. A strong correlation observed between vegetation indices and weed coverage. Based on the collected data, weed maps are created in appropriate software environment, thus the spatial distributions of the weeds are determined. The species level discrimination and the recognition of weed structural parameters were executed based on the 3D point cloud data by Leica ScanStation C10 laser scanner.

  • Effect of Soil Covering on the Soil Enzyme Activity of Integrated Orchard
    20-29
    Views:
    97

    The purpose of our experiments is to discover the effect of different soil cover matters (agrofoil and black polyethylene) on the activity of some enzymes (phosphatase, saccharase, urease, catalase, dehydrogenase) occuring in soil. Soil samples were taken from a cider apple plantation of the Fruit Producing Research and Advisory Kht Újfehértó. The enzyme activity was measured according to Krámer and Erdei (1959a), Kuprevič and Tsherbakova (1956), Kuprevič et al. (1966), Frankenberger and Johanson (1983), Mersi and Schinner (1991). Soil moisture content was by conventional (drying chamber) method measured during every sampling and enzyme activity was transpolated to absolute dry soil. Results were estimated by mathematical methods (variation analysis, correlation counting). Soil samples were taken by trials 5 times (in every two months) a year in the vegetation period from March to November.
    By recording the monthly changes of the enzyme activity we have observed the following. The activity of the phosphatase was generally the highest in May and the lowest in November. Depending on the trials, high values were also measured in March and September. The activity of the saccharase was generally the highest in November and the lowest in June, but at the same time peaks even occured in May and September. The highest urease avtivity was measured in September and November, and the lowest activity in May and July, also depending on the trials. In the year 2000, after a deep point in March, the activity of the catalase was the highest in November or by certain trials in September. In 2001, the lowest activity was also measured in March, but the highest activity appeared in November in case of one-minute trial, and in May in consequence of two-minute trial. Finally the activity of dehydrogenase was the highest in November and the lowest in July apart from the model years.
    There were essential differences in rainfall of the two experimental years which was reflected in the enzyme activities. There was a poor positive significant relationship between soil moisture content and enzyme activity values in case of phosphatase, saccharase, urease (r=0,426; 0,480; 0,396) respectively. In case of catalase1 (r=0,518), catalase (r=0,556), dehydrogenase (r=0,559) we obtained a medium strong positive relationship between soil moisture content and enzyme activity values. By evaluating the effect of different trials in case of every examined enzyme significantly higher values were detected in soils covered by agrofoil (a porous black polyethylene) than in soils covered by black polyethylene or in uncovered soils. Moreover, the soil covered by black polyethylene showed significantly higher enzyme activities (besides phosphatase) than the control soil. Thus soil-covering meant statistically significant advantages in enzyme activity as opposed to uncovered soil proved.