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Drought stress monitoring by laboratory and satellite spectral methods in an apple orchard
7-9.Views:470An orchard can be examined on the basis of spectral data, using such methods with which the reflected radiation can be divided into a large number of (several hundreds) small spectral channel (some nm). Based on the spectral characteristics of the canopy, or the different index numbers calculated from hyperspectral data the water supply conditions of foliage can be well characterized. The research site is an intensive apple orchard, which located in Debrecen University, Centre for Agricultural and Applied Economic Sciences, Farm and Regional Research Institute at Pallag. During our experiments the evaluation of spectral, non-invasive measurement method are carried out for detecting stress symptoms caused by drought. Furthermore, MODIS NDVI time series data were analyzed for orchards situated in North-Eastern part of Hungary in drought effected and wet years in order to detect differences. Significant differences in NDVI values were detected after the end of June.
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Applied spatial analytic tools in orchards with special regard to agro-ecology
17-19.Views:992Our investigation was carried out in several orchards in Hungary. This study reviews applicability of the different spatial analytical techniques in orchard especially models based on surface relief, such as digital elevation model, digital terrain model, slope and aspect maps. In recent time, the generation of digital elevation model has become a popular examination method. However, the elevation models generated from contour lines or elevation points could be applied to evaluate agro- ecological potential of fruit orchards to some extent. The highest deficiency of these models is the fact that these show the altitude of soil surface only and do not demonstrate landmarks on the surface. Consequently, the calculation of the radiation value results data relating to soil surface. The terrain model generated and applied by our team demonstrates fine surface texture and the landmarks in the orchard, so it is suitable for further examination.
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Hyperspectral data in water stress detection
15-17.Views:380Remote sensing methods are applied widespread to investigate large land fields. Within these methods the status of certain vegetation can be determined based on the reflectance spectra of the chlorophyll, in order to support agriculture, forestry and the evaluation of soil pollution. The main aims of our study were to determine and validate the reflectance spectra of fruit tree species, in order to facilitate the identification and evaluation of stressed fruit trees in orchards.
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Left, right, up and downstage: leaves and lateral roots histological trait prospection for drought tolerance in commercial Coffea arabica cultivars
44-65.Views:665The climate change and water deficit challenges plant producers all over the world, and have consequences to coffee production and quality. In this research we have approached anatomical traits from vegetative organs of 13 Coffea arabica genotypes, selected based on their contrasting behavior to water deficit. Leaf blade, petiole and primary root cross sections were evaluated, and the epidermal, fundamental, and vascular tissues descriptive anatomy, histometric and histochemistry examined. Despite all plants were in the same environment (CEPC/EPAMIG, Patrocínio, MG, Brazil), there were differences among the genotypes and groups of more tolerant and more susceptible accesses. Petiole cross section, vascular tissue and phloem and cambium; and percentage of stele, pericycle and phloem and cambium in primary roots exhibited differences among the contrasting genotypes, highlighting an inborn association of vascular tissue and other features with water deficit resistance. This association was observed in the mild to medium correlations among vascular tissue, epidermis, phloem and cambium in roots and petioles. Possible relation of qualitative traits such as the lignification of root epidermis, lipidic substances in outer cortical cell layers, and area/number of cell layers in the cortex are approached as possible traits in the seek for water deficit tolerance in C. arabica.
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Influence of soaking periods and temperatures on germination and respiration of pea seeds
69-71.Views:492Samples 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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Ecotoxicology of Copper in Horticultural Soils: A Review
7-18.Views:660Nowadays, the world is facing the problem of environmental pollution because of the increase of man’s needs requires development in life activities, progress industrialization, transportation tools, enhancement of agriculture and exploitation of natural resources. Soil and water resources are extremely exposed to pollution from different aspects. Agrochemicals in particular, have created severe problems, since they release thousands of chemicals to the environment. Several studies on the effect of environmental pollutants on agroecosystem have been carried out. On the other hand, the importance of trace elements as environmental pollutants is well known and well documented in literature. Cu contamination to agricultural soils has been accelerated due to its wide and repeated use in agriculture and horticulture as fertilizers or fungicides to protect vines, citrus trees, and other fruit crops against fungus diseases. Applied Cu from different agrochemical sources to agroenvironment may be adsorbed and are transported to the groundwater table and pollute it besides polluting the soils. The use of Cu-based fungicides in vineyard soils is widely documented worldwide. It has been found that many countries contain concentrations in excess of 100 mg kg−1. Importance of study of transport of Cu arises due to the fact that Cu is absorbed in soils and also reaches the groundwater table, thus polluting both soil and ground water. It is often more important to be able to estimate the mobile fraction, the readily soluble fraction, the exchangeable fraction, or the plant available fraction of Cu content of a soil as a more direct indication of the likelihood of deleterious or toxic effects on soils and groundwater. Therefore, the aim of present work was to highlight the behavior and ecotoxicological effects of copper on horticultural soils.
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Precision geoinformatical system of the pear gene-collection orchard
43-50.Views:890The principle task of the sustainable development is the preservation of the genetic variety, which is similar challenge in the horticulture regarding the sublimation of fruit species. The breeders of the traditional fruit strains give stock to the sustenance diversity of the agro-environment on the species and landscape level. In 2009, hyperspectral images have been taken by AISA Dual sensors from the pear gene pool in Újfehértó, Hungary. The hyperspectral data cube (in the wavelength range of 400-2500 nm, with 1.5 m ground resolution) ensured possibility to make the spectral library of pear species. In the course of the simultaneously field work the spatial position and individual extent of all pear trees was defined to set up a detailed GIS data base. The water stress sensitivity of single species and the descriptive spectral curves were determined with common evaluation of the spectral and spatial data. Based on the unique methodology processing and the hyperspectral data base suitable strains can be chosen for agro-environment and let take adaptive stocks regarding climate change into the genetic grafting work. Furthermore we could determine and map the sparsely species in the region with the help of the hyperspectral data.
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The effect of climatic anomalies on the nutrient supply of fruit plantations (Minireview)
111-116.Views:12784Climatic conditions play an important role in agricultural production. It has a profound influence on the growth, development and yields of a crop, incidence of pests and diseases, water needs and fertilizer requirements in terms of differences in nutrient mobilization due to water stresses. Nowadays, we have to know the dark side of the weather events because it is causing more and more problems and significant hazards to many horticultural regions in Hungary. The aim of this study is to explore the problems of nutrient uptake following climatic anomalies and response. These problems are: (i) water supply problems (water-stress); (ii) drought and frost as temperature strees. Reviewing the effects and nutrient disorders caused by climatic anomalies, the following statements can be taken:
- Nutrient demand of trees can be supplied only under even worse conditions.
- The most effective weapon against damage of climatic anomalies is preventative action.
- When developing a fruit orchard, three factors should be taken into consideration: "Location, Location, Location".
- Moreover, proper choice of cultivars, species and cultivation should provide further possibilities to avoid and moderate the effects of climatic anomalies.
- Fruit growing technologies especially nutrition should be corrected and adjusted to the climatic events as modifier factors.
- Urgent task of the near future is to correct and adjust the tested technologies of fruit growing according to these climatic events as modifier factors.
Optimal nutrient supply of trees decreases the sensitivity for unexpected climatic events. To solve these problems supplementary, foliar fertilization is recommended, which adjusted to phonological phases of trees.
Another solving is groundcover of soil means a potential opportunity to temper or even avoid climatic anomalies.
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Effect of over tree cooling irrigation on ‘Bosc’ pear orchards microclimate
153-156.Views:1333Irrigation in some countries is a horticultural practice mainly used only to supply water. At the same time the use of microsprinklers have a powerful infl uence on the changes of temperature in orchards. When the air’s temperature is high (about 20 °C or higher) the evaporative cooling irrigation signifi cantly decreases the plants’ surface temperature and air temperature. The cooling effect is stronger when the air is dryer. By using cooling irrigation regularly, canopy temperature can be decreased so that the beginning of blooming can be delayed. Also if the blooming is early and frost probability is high, serious damages can happen in orchards. The benefi cial effect of cooling irrigation is the temperature reduction and frost protection. In March 2010, one month earlier than the expected blooming an irrigation system was established to produce anti-frost treatment and regulate the micro-climate of a Bosc pear orchard which belongs to the University of Debrecen (Hungary). The objective of sprinklers was to cool the air by increasing water evaporation and relative humidity. The position of the micro-sprinklers was planned in three levels (around the tree trunks, a few cm near to the soil surface, in the crown region and above the crown, a half meter higher). The results showed that the water sprayed in the orchard by micro-jets infl uenced decisively the temperature of the plantation. At higher temperatures (around 20 °C), the drop of temperature may attain 5–7 °C. A low relative humidity of the air may increase the relative effect. When water was applied at intervals of 15 minutes for ten times a day from 8 am to 18 pm, the air, fl owers and bud’s surface temperature could be kept low. At certain days when the temperature was higher than 10 °C, irrigation was used at night time in similar 15 minutes intervals, from 18 pm and 6 am. The beginning of bloom could be delayed for more than ten days. The Bosc pear variety blooming dynamics was characterized by a logistic curve in the treated as well as in the control plot. In the treated plot, the curve was steeper than in the control one in spite of the equal temperatures measured in the plots. Under Hungarian climatic conditions, the method was successfully used to delay blooming dates. The main result was the diminution of the frost damage in the spring that assured pears yields.
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Cooling irrigation as a powerful method for microclimate modification in apple plantation
33-37.Views:1120Irrigation in some countries is a horticultural practice mainly used only to supply water. At the same time the use of microsprinklers have a powerful influence on the changes of temperature in orchards. When the air’s temperature is high (about 20 °C or higher) the evaporative cooling irrigation significantly decreases the plants’ surface temperature and air temperature. The cooling effect is stronger when the air is dryer. By using cooling irrigation regularly, canopy temperature can be decreased so that the beginning of blooming can be delayed. Also if the blooming is early and frost probability is high, serious damages can happen in orchards. The beneficial effect of cooling irrigation is the temperature reduction and frost protection. InMarch 2010, one month earlier than the expected blooming an irrigation system was established to produce anti-frost treatment and regulate the micro-climate of a Gala apple orchard which belongs to the University of Debrecen (Hungary). The objective of sprinklers was to cool the air by increasing water evaporation and relative humidity. The position of the micro-sprinklers was planned in three levels (around the tree trunks, a few cm near to the soil surface, in the crown region and above the crown, a half meter higher). The results showed that the water sprayed in the orchard by micro-jets influenced decisively the temperature of the plantation. At higher temperatures (around 20 °C), the drop of temperature may attain 5–7 °C. A low relative humidity of the air may increase the relative effect. When water was applied at intervals of 15 minutes for ten times a day from 8 am to 18 pm, the air, flowers and bud’s surface temperature could be kept low.At certain days when the temperature was higher than 10 °C, irrigation was used at night time in similar 15 minutes intervals, from 18 pm and 6 am. The beginning of bloom could be delayed for more than ten days. The Gala apple variety blooming dynamics was characterized by a logistic curve in the treated as well as in the control plot. In the treated plot, the curve was steeper than in the control one in spite of the equal temperatures measured in the plots. Under Hungarian climatic conditions, the method was successfully used to delay blooming dates. The main result was the diminution of the frost damage in the spring that assured apple yields.
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Relaco: a product to reduce water shoot formation around pruning wounds in pome fruit trees
30-31.Views:198Larger cuts made during the winter pruning of pome fruit orchards a number of serious problems: the wounds serve as entrances for several branch-infecting pathogens, the numerous water shoots formed around the cut edges consume assimilates, shade the developing fruits, make the canopy dense, reduce the effectiveness of the pest management and cause extra work during next seasons pruning work. These problems can be eliminated by using proper wound protectants, like Relaco, a new Romanian wound protectant to cover larger pruning cuts of apple, pear and quince trees.
The treaments by Relaco resulted in a significant decrease in both the number and total length of water shoots formed around the cut egdes.
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Colour and water content detection of sweet cherry by portable spectrometer
23-26.Views:35464Based 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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Pilot study for irrigation modelling of a pear plantation
81-84.Views:3930Our investigation was carried out in the area of Fruit growing Research and Consultant non-profit company, at Újfehértó. The pear requires large water quantity, but this pear plantation hasn’t irrigation system not yet. This study reviews the drainage conditions of the area based on digital elevation model, and examined the canopy cover of pear trees by evaluating of the hyperspectral image. Our aims were to determine the exact watershed based irrigation modelling and determining of the canopy% of the pear orchard to facilitate a precision irrigation decision support system.
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Studies on the drought responses of apple trees (Malus domestica Borkh.) grafted on different rootstocks
29-36.Views:1391The morphological and chemical changes in the leaves of eight apple varieties grafted on M4, M26 and MM 106 rootstocks were examined during fruit development in non-irrigated plantation. The aim of the experiment was to examine the defensive mechanisms in apple trees under the mild and serious dryness occurring during fruit development. The content of a relative chlorophyll (SPA D value) of the apple leaves on eastern side of the trees was lower than western and southern sides under drought occurring du ring fruit devclop111ent Under sustained drought from first of July to August the SPAD value, the weight of leaves were larger and the stomata density was significantly larger than in the previous periods. There was a close positive significant correlations bet ween SPAD and stoma density both in the group with less sensitive to drought (r=0,8429) and in the large water demanded group (r=0,9209) equally. The rate of increase in SPAD values and the stoma density was slower in the group with drought tolerant, than in the group required good water supply. The varieties being sensitive to water deficite such as Akane. Pink Lady and Red Rome van Well have a l ready responded intensively to short time of drought by the increasing of carbohydrate and antioxidants product ions. At 42 days of sustained drought as soon as the level of carbohydrate in the leaves decreased, the antioxidant s contents of the leaves rised suddenly in the apple varieties with moderate water requirement s as Greensleeves and ldared. Gala apple variety seemed to be able to defend the drought for longer time because there was no change in relatively high level of carbohydrates and antioxidants of their leaves under severe drought during fruit development.
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Integration of terrestrial laser scanning and spectral canopy scanner in horticulture applications
15-18.Views:1044One of the most difficult challenge in the everyday practice to describe the canopy growing of fruit trees in an orchard. The photosynthetic activity is the basic of the primer production of plants. The measurement of leaf area and determination of the photosynthetic activity could be occurred with some elaborated methods between experimental conditions. In this article we present such an integrated methodology, which is ideal to determine the geometric and spectral characteristic of fruit trees between field conditions.We have carried out laser scanning technology to investigate the geometric-topological characteristics and parallel the active infra-red sensor to collect spectral data about an apple orchard. The surveys were worked out in an intensive apple orchard with drip irrigation system, protected by hail net in Study and Regional Research Farm of the University of Debrecen near Pallag. This study shows the filtering and interpretation methods of created data. The produced high accuracy data can be directly used in the precision horticulture. It could serve as a guiding data to implementation a future “virtual horticulture”. Higher spatial and temporal resolution could help for a better recognition of water balance of orchards.
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Illumination-Independent Reflectance Information Acquirement for Leaf Water Potential Measurement on the Example of Satsuma Mandarin
75-79.Views:208Mandarin 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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The effect of storage to optical properties in case of two apple fruit varieties
33-36.Views:909The 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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The role of meteorological variables of blossoming and ripening within the tendency of qualitative indexes of sour cherry
7-10.Views:954We 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. -
Industrial-scale plantlet production by seed priming and nursery tray seeding method in Sida hermaphrodita L. Rushby
71-74.Views:401Virginia mallow (Sida hermephrodita Rushby), Malvaceae family, is a perspective perennial herb able to yield a biomass crop through the last two decades. In our previous studies, we examined two factors relating to seed germination percent and seed germination power during our research: the influence of hot water treatment and the effect of exogenous or endogenous infection of seed. Following these recognition we modifi ed our technique, in such a way that we fractionated the seeds based on their fresh weight / or relative density before we carried out the treatment. When we fi ltered the fl oating seeds on the surface of water, the hot water treatment was performed considerably better on the sink seeds after separation. Therefore, by this special priming process we were able to reach 80% germination capacity of Virgina mallow seeds under laboratory conditions (26 oC without illumination). From all nurseries tray methods preliminary results, it is clear that, Sida seeds, which were treated with these methods, gave the best growing rate for industrial uses.
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Assessment of soil characteristics in orchard
11-14.Views:1052The research field was at Siófok, in Hungary, which is situated in the South East side of Lake Balaton. The physical characteristic of the soil is sandy loam and loam and the peach orchard is irrigated. The detailed goals were mapping and analyzing of physical properties of the soil in water management point of view, mapping the acidity and CaCO3content of soil for precision liming, measurement of humus the element content. Sites with different physical characteristics (from sandy loam to loamy clay) could be distinguished. The reason for this is that besides the possible increase of clayminerals, the increasing rate of colloidal humus content contributes to larger soil plasticity. Statistics also proved positive and strong correlation (r=0.822) between the soil plasticity and humus content. In the case of pH, only a small part of the orchard is has to be limed, since most of the orchard has neutral pH, which is advantageous for nuts and stone fruits. It has to be mentioned, that the CaCO3 supply is also appropriate for the stone fruits. Based on the results hyperspectral imagery can be a good solution for detecting calciferous soils, although these measurements are still need validation.
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Importance of orchard floor management in organic fruit growing (nutritional aspects)
61-67.Views:1417Worldwide research goals and concerns are to soil conservation and improve. This conception is mostly actual in horticulture where the numbers of high-density plantings are continuously increasing. High-density orchards cause more intensive nutrient and water uptake. So that the preservation of soil moisture and nutrient level are key factors in qualified fruit growing. On the other hand due to the climatic changes the water supply of trees will be satisfied among worse conditions than some decades ago. Appearance of water supply problems and water stress is increased in organic growing, where the number of corrections is limited anyway. Furthermore, floor management is a successful tool in weed management which causes many problems for organic growers due to the prohibition of synthetic herbicides. This paper will mainly focus on the nutritional aspects of methods of orchard floor management for growers adopting organic fruit management to make their production profitable.
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Foliar Nutrition and Post-Harvest of Onion Seed: Effects of storage temperatures, storage period and foliar nutrition
29-47.Views:495The 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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Volumetric estimation of an intensive apple orchard with GIS
7-10Views:873Remote sensing instruments and methods have become widespread in all segments of agriculture and horticulture. Among the innovative development of remote sensing instruments, the 3D laser scanner is one of the newest technique, which overtop in the spatial data collection. Terrestrial laser scanning is an appropriate tool for identifying such biophysical parameters like the structure of trees and branches, growth of volume. Determination of these parameters are time consuming and complicated with traditional methods. The examination was carried out in the Study and Regional Research Farm of the University of Debrecen near Pallag. We used Leica ScanStation C10 terrestrial laser scanner to estimate volumetric properties of the intensive apple orchard. Two rows of the study area were surveyed, where the height and stem diameter of apple trees were measured with Geomagic Studio 12 GIS Demo Software. Based on the built-in algorithms, the volume of each tree were defined by the software. The measured and calculated data was correlated, and middle correlations were detected. Estimated volume results could be useful for further investigation such as CO2 fi xing, which is an important factor for ecological service of the plantation.
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Scheduling of irrigation in snap bean (Phaseolus vulgaris var. nanus) using canopy temperature
89-94.Views:251The present paper evaluates the result of irrigation experiments carried out on snap beans sown in spring and summer and grown with and without irrigation. The experiments were run over the course of 12 years. In the average of 12 years, the yield was 2.8t ha-I for spring sown and 1.9 t ha-I in summer-sown plants without irrigation. The lowest level of profitable production, the 5.5t ha-I was reached twice in the case of spring sowing and only once in the case of summer sowing. Profitable yield production can be ensured only with regular irrigation and thus the yield may be increased by 4-5 times. In four of the twelve years we determined the canopy surface temperature of snap bean stands with and without irrigation. A Raynger II infrared remote thermometer determined the canopy surface temperature every day at 13.00 hours. The canopy temperature can well characterize the water supply of plant stands. This parameter may be used for describing the degree of drought and the water turnover of plant stands with different water supply. The positive values of foliage-air temperature differences (SDD) numerically express the degree of drought and the water supply of the crops. The results indicated that a 1 °C higher SDD value may cause 90-130 kg/ha yield loss.
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Effects of crop load on tree water use in apple (Malus x domestica Borkh.)
29-31.Views:290Sap flow rate measurements were carried out during two consecutive ('on' and 'off') years in an apple orchard cv. 'Florina' M.26 to analyse the effects of various crop load on tree water use. Sap flow rate was measured by thermal dissipation method in trunks of nine trees from June to the harvest. Crop load was between 0.2-9.0 fruits • cm -2 of trunk cross section area (equal to 0.5-35.0 fruits•m-2 of leaf area), trunk diameter varied between 4.7-8.7 cm.
Total leaf area was estimated by leaf counting or using shoot girth and leaf area relationship. In both years, fruit growth rate was determined by measuring diameter of 280 marked fruits with 7 days frequency. Fruit volume calculated as a function of fruit diameter based on a previously determined relationship.
Total leaf area of trees ranged from 4.4 to 19.5 m2 and it was closely related to trunk cross section area. At high crop load the fruit growth rate peaked in August with 0.51.tree-l.day-1 and the leaf area specific total fruit volume reached 61 m2 before the harvest.
There was a linear relationship between total leaf area and daily water use, while the leaf area specific water use was influenced by crop load rate. The relationship was described by piecewise linear regression with the breakpoint at crop load rate of 12 fruits•m2 of leaf area. At low crop load the slope of the fitted regression line was less than at high crop load rate.
