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Evaluation of water balance in apple and pear trees
193-198Views:102A significant proportion of the aboveground green and dry weight of the plant constitutes the foliage. The canopy is an important factor
of plant growth. On one hand the canopy absorbs the solar energy, which is necessary for the photosynthesis, on the other hand accumulates
the absorbed nutrients by the roots, and the most of the water-loss happens through the foliages. The determination of the full canopy is not
an easy target. In our research we developed a measurement method to determine the leaf area. With the parameters of the examined tree
(leaf length and maximum width) and the data of ADC AM 100 leaf area scanner we determined the k-value, with which we can easily and
fast evaluate the leaf surface. Furthermore we defined from the water balance of compensation lysimeters the cumulative transpiration of
fruit trees and the efficiency of water use of trees. -
Experiment of quality properties of dehydrated fruits
7-15Views:100The lyophilization is the joint application of freezing and drying. It is an up-to-date conserving procedure, the point of which is that the humidity existing in the frozen humid material is transferred from the solid state directly into the gaseous state at a temperature below 0 oC under vacuum. Out of the procedures applied nowadays, this is the most tolerant drying process.
With regard to the high investment and operational costs, freeze drying is applied only for valuable, heat-sensitive materials when the technological aim is to preserve such properties as aroma, taste and colour as well as such components as proteins and vitamins. This procedure is suitable for drying and conserving certain foodstuffs, stimulants, organic chemicals, medicines and similar sensitive and valuable materials.
In our institute, we have been conducting freeze drying experiments with regional fruits and vegetables since the year 2005. During the first phase, we examined the heat- and material transfer as well as the abstraction of humidity, while during the second phase we analysed the rehydration ability and nutrient content of the freeze-dried materials as compared to those dried with the method of convection. Moreover we have conducted penetration measurements with a portable hardness tester.
To sum up the results gained so far, we can state that the quality of the lyophilized materials is better than those dried in the traditional way. It originates partly in the fact that the temperature and pressure applied for the freeze drying are smaller and the drying period is far longer than for the convection drying.
In contrast to convection-dried materials, freeze dried materials set in close to their original water-content, keep their original shape and size after being rehydrated. The reason of it the porous, spongy structure (flexible cell wall) of the lyophilized products which is able to take up moisture quickly. In addition, the lyophilized products can be rehydrated faster than those dried in the traditional way.
Regarding the results of the chemical analyses, the following conclusion can be drawn: the vacuum freeze drying results a small decrease of nutrient content and nutritive value for the lyophilized products.
The results of the hardness tests support the statement that the majority of agricultural materials cannot be considered as an ideal flexible body, because during the experiment the flexibility coefficient changed when going from the surface of the material inwards. In addition, the penetration tests also confirm that the surface of the convection-dried vegetables is at least 1.5-3 times harder than that of the freeze-dried products. The reason of it that it takes place during the drying denaturation processes.
The article summarizes the results of our research work listed above, in accordance with our experiments conducted by using the characteristic fruits (apple, plum) of the Nyírség Region. -
Effect of Soil Covering on the Soil Enzyme Activity of Integrated Orchard
20-29Views:82The 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. -
Calculating possibility of the leaf area index of apple and pear trees
229-233Views:110A significant proportion of the aboveground green and dry weight of the plant constitutes the foliage. The canopy is an important factor of plant growth. On one hand the canopy absorbs the solar energy, which is necessary for the photosynthesis, on the other hand accumulates the absorbed nutrients by the roots, and the most of the water-loss happens through the foliages. The determination of the full canopy is not an easy target. In our research we developed a measurement method to determine the leaf area. With the parameters of the examined tree (leaf length and maximum width) and the data of ADC AM 100 leaf area scanner we determined the k-value, with which we can easily and fast evaluate the leaf surface.
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The future of apple growing in the Northern Great Plain region
35-38Views:89We revealed and assessed those macroeconomic data which enabled us to identify the outstanding role of agriculture and within it that of fruit production. Based on this, it can be said that soil is the most important natural resource of Hungary. The appropriate combination of the additional resources required for production, labour and assets can provide a comparative advantage for the Northern Great Plain Region.
The Northern Great Plain Region is one of the most underdeveloped regions in Hungary, so its development is a political objective. When analysing the economic sectors in the region, the important role of agriculture is obvious and it is also clear that the industry and the tertiary sector can only have an alternative income generating role in the future also. Therefore, it is important that the regional development funds of Hungary and the European Union are directly or indirectly aimed at improving agricultural development and competitiveness. -
Previous data on the relationship between the intensity of pruning and the degree of damage in integrated and organic applegrowing systems
47-52Views:87In Hungary, fruit growers are increasingly interested in environmentally friendly growing methods, such as organic and integrated systems. Vital is the establishment of a strengthened system of cultivar-pruning-plant protection in production technology. Consequently, our aim was to examine the susceptibility of apple cultivars to diseases and pests and the effect of pruning technique on diseases and pests in organic and integrated growing systems.
Two pathogens (Venturia inaequalis, Podosphaera leucotricha) and two pests (Leucoptera malifoliella, Pannonychus ulmi) were observed in organic and integrated systems under „strong” and „weak” pruning techniques. Our results on six cultivars showed that the pathogens and pests infested the trees more in the organic system, as compared to that of integrated production. The pruning technique affected mainly the susceptible
cultivars to diseases and pests. The „weak” pruning technique caused a higher level of diseases and pests infestations than the „strong” pruning technique, especially in the organic growing system. The likely reason is that the shoots grow fast and powerfully under “strong” pruning technique. This supports better preservation of the trees supported by susceptibility of plant tissues to diseases and pests. -
Relationships of Fruit Production and Regional Development in the Northern Great Plain Region
181-187Views:87The role of retaining population in agriculture is stronger and more significant in the long run in the North Great Plain Region compared to other regions. The region has a significant processing industry along with a good basis for producing raw materials, developed food processing capicity and high quality agricultural products typical of the region. The GDP in agriculture, forestry and game management is somewhat higher than the national average.
Variety is of cardinal importance when establishing the quality of horticultural products and determining the product value. The Hungarian breeding results of apple, quince, apricot, cherry, raspberry, red and black currant are promising.
The regulation system of EU the vegetable and fruit market is based on Retail Cooperatives Producers. With the establishment of national vegetable- and fruit production and retail organizations, the market regulation, production and quality development issues of the sector can be handled and solved. Reaching EU standards in fruit production can only be achieved with up-to-date plantation systems and breed selection. A key issue in development is establishing the required financial resources for investments and updating production. In order to reach these standards, significant state subsidies and good credit conditions are needed. By solving these tasks, the sector is expected to become self-financed without government help.
The pursuit of safer production, improving quality and increasing yields require the establishment of up-to-date irrigation systems. The improvement of family farms, motivating land concentration is necessary for increasing average size of plants. Establishing the above mentioned conditions is important since the vegetable-fruit sector is of great significance in the employment of rurally based population, improving their living conditions and executing rural development programs. -
Inland and foreign Erwinia amylovora isolates by carbohydrate utilization
29-33Views:73Fire blight, a plant disease caused by the bacterium Erwinia amylovora, produces serious losses in apple and pear orchards all over the world. Since the appearance of fire blight in Hungary (Hevesi, 1996) Erwinia amylovora isolates were collected in different years, from different hosts and areas in order to establish gene bank for future epidemiological studies. We had isolates from foreign countries as well. The aim of our research was to compare all of the Hungarian and foreign isolates by carbohydrate utilization.
In our experiments effect of carbohydrates on E. amylovora multiplication was determined using API 50 CH strip (bioMérieux, France). By the API 50 CH strip method we checked a number of unstudied carbohydrates. The results of the tests shows colour changes. Based on utilization of 49 carbohydrates of API 50 CH kit by E. amylovora isolates, two groups of carbohydrates can be defined: “Utilized” - and “Not utilized” carbohydrates. All isolates utilized 20 different carbohydrates after 164 hour incubation. Conversely, isolates also could be divided into four groups (1, 2, 3, 4) by arbutin and raffinose utilization. In group 1.-isolates utilize arbutin; 2.- utilize raffinose; 3.- utilize both arbutin and raffinose; 4. -utilize neither arbutin nor raffinose. Presumably carbohydrate content of nectar could play an important role on invasion of the (E. amylovora) bacterium via flower.
It could be concluded that the carbohydrate utilization – completed with genetic analysis – can be used for characterization of Erwinia amylovora isolates. -
Application of advanced environmental assessment methods in orchard management
221-225Views:113Our 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.
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Effect of Soil Covering on CO2 Production and Cellulose Decomposition Activity
198-201Views:30In our experiments the effect of different soil cover matters (agroszövet and black polyethylene) on the CO2 production capacity and on the soil cellulose decomposition activity was studied. We also examined the relationship between the CO2 production and the cellulose decomposition activity. The trial was carried out in an apple plantation in Újfehértó. The CO2 production were determined after Witkamp with 5 days’ incubation period, the cellulose decomposition activity was measured according to Unger. Results showed that CO2 production and cellulose decomposition activity was higher in control soil almost in every cases. In respect of CO2 production the black polyethylene gave better values than the agroszövet.
In 2000 the cellulose decomposition activity was significantly higher under covered soil than under uncovered every time. In spring of 2001 the controll but in summer and autumn agroszövet was significantly better. In summer and autumn black polyethylene prove non-significantly better than control. In average of two experimental years significantly higher cellulose decomposition activity was detected in covered soils than in control.
In the most occassion a close connection was observed between cellulose decomposition activity and CO2 production. In spite of this the correlation was not significant in controll at all. Significant relationship was only found in spring and summer of 2001 under agroszövet, in spring and autumn of 2000 and in summer of 2001 under black polyethylene. -
Environmentally-benign plant protection possibilities against domestic Monilinia spp. in organic apple and stone fruit orchards
101-105Views:115In this study, possibilities of environmental-friendly plant protection against domestical brwon rot species were summarized for oecological pome and stone fruit orchards. Symtomps of the two most important brown rot species (Monilinia fructigena (Aderh. & Ruhl.) Honey and Monilinia laxa (Aderh. & Ruhl.) Honey) were described and then cultivar susceptibility to brown rot was discussed. Furthermore, mechanical, agrotecnical, biological, and other control possibilities (stone powders, plant extracts and restricted chemical materials) were shown.
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Sour cherry anthracnose and possibilities of the control with special regard to resident Glomerella population in sour cherry plantations of East Hungary
12-17Views:133Anthracnose is considered one of the most destructive diseases for sour cherry production due to the rapid development of the disease on fruits. Glomerella cingulata (Stoneman) Spauld. & H. Schrenk (anam.: Colletotrichum gloeosporioides (Penz.) Penz. & Sacc. in Penz.) has been the fungal pathogen responsible for anthracnose in last decades. Yield losses greater than 90% may occur under epidemic conditions. C. acutatum (J.H. Simmonds, 1968) strains were isolated of sourcherry plantations in East Hungary and this pathogen, new for Hungarian microbiont became recently dominant. Contrarily to the former species it is certainly transmitted with ants during fruit ripening. About third of strains proved to be cutinase producers that enable them to actively penetrate via cuticule, and these strains infect directly berries of blackberry, grape and tomato as well as plum and apple. Most of cutinase negative strains could also infect these fruits after mechanic injury. All strains of both species produce amylase, cellulase, lecithinase, lipase, polyfenoloxydase and protease in vitro, although the activity of these enzymes highly varied in the medium. The only C. acutatum strains produced noticeable amount of chitinase. Strains, tolerant to recently applied fungicides to control the anthracnose, could be isolated of sour cherry plantations that might be the cause of ineffectiveness of control measures in 2010. The mycofungicide containing mixture of three Trichoderma species in oil carrier could efficiently depress the development of anthracnose in ripening sour cherry.
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Applicability of precision weed detection technologies
163-168Views:156In 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.