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Ecotoxicology of Copper in Horticultural Soils: A Review
7-18.Views:276Nowadays, 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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Anatomical structure of stem in the above- and underground portions of Rosa rugosa suckers
89-91.Views:160Comparitive histological studies were made on the underground and the aboveground stem parts of Rosa rugosa taken from one year old suckers. The underground stem parts were characterized with thicker primary cortex, phloem and pith, weaker phloem fibers, wider cambial zone, medullary rays, xylem and phloem rays as compared with the aboveground stem parts. The most marked differences in the underground stem parts were in the wide cambial zone and in the development of some adventitious roots.
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COVID-19 outbreak lockdown and its impacts on marketing of horticultural produces in Zimbabwe
38-45.Views:470Coronavirus disease of 2019 (COVID-2019) outbreak resulted to a global health problem. Lockdown was one of the common options suggested to curb the pandemic. Horticultural produces are perishable so delayed post-harvest marketing cause losses. This study aimed at evaluating the marketing of horticultural produces and farmers’ level of preparedness during the COVID-19 lockdown. A self-administered questionnaire was posted online from April 7 to May 7, 2020 the first month of COVID-19 lockdown in Zimbabwe (began on March 30, 2020). The study targeted horticultural farmers around Harare peri-urban and had 300 respondents. Data on sociodemographic, farmers’ behavior, awareness and attitude toward marketing and desire to minimize post-harvest losses was obtained. Frequency counts and percentages were determined. Chi-square tests on independent variables were done to test associations with demographics using SPSS version 8. There were significant (P<0.05) relations between awareness and attitude toward marketing, age and level of education. Demographic variable influenced the famers’ marketing behavior and attitude during COVID-19 lockdown. Most farmers reported highest (>35%) produce sale leftovers at the markets and spoilage during than prior the COVID-19 lockdown. The lockdown resulted to low sales and most farmers were unprepared for any crisis during the marketing stage of their production. The research contributed to an understanding of how a crisis situation influence marketing of horticultural produce and raises awareness regarding post-harvest losses. A qualitative study is recommended as a follow-up of this work.
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Self-incompatibility alleles in Esatern European and Asian almond (Prunus dulcis) genotypes: a preliminary study
23-26.Views:184Almond [Prunus dulcis (Mill.) D. A. Webb.] as one of the oldest domesticated plants is thought to have originated in central Asia. Gametophytic self-incompatibility of almond is controlled by the highly polymorphic S-locus. The S-locus encodes for an S-ribonuclease (S-RNase) protein in the pistils, which degrades RNA in self-pollen tubes and hence stops their growing. This study was carried out to detect S-RNase allelic variants in Hungarian and Eastern European almond cultivars and Turkish wild growing seedlings, and characterize their S-allele pool. Five new alleles were identifi ed, S31H, S36-S39 in Eastern European local cultivars. The village Bademli and Akdamar island are two distinct places of almond natural occurrence in Turkey. Trees growing wild around Bademli city showed greater genetic diversity than those originated on Akdamar island. Many of the previously described 45 S-RNase alleles have been also detected in these regions. Homology searches revealed that Turkish almonds carried some P. webbii alleles indicating hybridization between the two cultivars and massive introgression events. Our results supply long-awaited information on almond S-allele diversity from regions between the main cultivation centres and the centre of origin of this species; and are discussed from the aspect of methodological developments and evolution of the cultivated almond.
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Storage ability and differences of carrot varieties defined by firmness changes measured with new non-destructive acoustic method
37-40.Views:174Carrot production in Hungary is getting more important these days. The condition of the quality insurance is to choose the proper variety of carrot and store on optimal conditions therefore measuring firmness and matter parameters are very important. Four varieties of carrots were measured (Bangor, Olympus, Napa and I3olero). The roots were stored in unsealed polyethylene bags at 4-10 degrees Celsius and 95% relative humidity. The vegetables were measured three times: at harvest, after I .5 months of storage and after four months of storage. The samples were tested by non-destructive acoustic. Stillness measuring method during the 112 days experiment for firmness. In laboratory were measured weight loss, dry material -NO3 and sugar content as an important matter parameters.
The firmness change as a function of storage time are the following: First part of the storage (after 60 days), the Napa variety changed least in the case of acoustical parameter, at the same time its weight Foss and dry material content were not rise significantly, while its sugar content increased with 50%. The l3olero variety had the highest changes of sugar content during storage. During the second storage period, the softening speed of all samples was increased. The Bolero had the highest average mass loss (32,7%) and NO3 content changes as well. All measurements showed the largest changes for the Bolero variety. The highest percentage of dry material content was found by the Bolero and Napa varieties (18-20%).
In this experiment, we found that the Bolero variety showed the greatest loss in compressibility during storage. If both firmness and weight loss results are considered, the Napa variety is found to be the most storable variety in sort period. The Bangor variety was found to be the best for long-term storage.
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Blooming time of some apricot varieties of different origin in Hungary
16-20.Views:325There are a number of self-incompatible and partially self-compatible apricot varieties which need cross pollination for suitable yield. We have to know their blooming time to select the appropriate pollen donor cultivars. The blooming period of 20 apricot varieties was observed in four subsequent years. Blooming time was affected by temperature conditions very much. Varieties studied were assigned to three groups according to their blooming time. The rate of overlapping of important variety combinations was observed. Sufficient overlapping of blooming period for safe pollination is usually ensured within the same group of varieties or between varieties of the neighbouring blooming time groups.
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Prolonging the vase life of cut Carnation 'GIOKO' by using different chemicals
65-68.Views:175Cut 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.
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The tests of effectiveness of Frostbuster under excessive weather conditions in an apricot plantation
87-91.Views:242Frostbuster is a new system, engine and technology, developed to protect fruit plantations from the frost damage. In order to raise domestic experiences and measurements, experimental approach has been initiated to prove the utility of the system under excessively low temperature in the plantation of the Siófoki Gyümölcstermesztési Zrt (Fruit Growing Co. Siófok). The first opportunity ensued in the night of February 23-24, 2011, when the temperature sank to 12°C below zero. The question was to see whether we could prevent the drop of temperature by the frostbuster technique. The margin of an anticyclone staying on East Europe secured a stable condition to make tests. The only difference from the imaginable conditions of dangerous frosts was the heat keeping capacity of trees was weak, much inferior than compared with trees in full boom. As a consequence, the tree rows represented much lower heat-capacity and cooled down much quicker than blooming trees in springtime, i.e. their temperature was more variable. The other difference was, compared with an episode in spring that the hard frost lasted much longer than usually in spring. For testing the system, those conditions had even more advantage. Six meteorological stations helped us in measurement. Data-collectors were timed to 1 minute distances and the bulk of data proved to be beneficial for testing the Frostbuster. The results prove that the system is adequate to keep the temperature continuously higher than the surrounding field under excessively low temperatures. Further measurements are still needed to find the optimal solutions fitting to the growing site and its microclimate. Results presented offer a basis of further proofs.
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Incidence of fungal diseases on leaves of apricot and plum cultivars in Hungary
29-31.Views:232In this two-year study, incidence of Polystigma rubrum on plum, and Apiognomonia erytrostoma on apricot were evaluated on several stone fruit cultivars in Hungary. Results showed that most apricot cultivars expressed symptoms caused by A. erytrostoma, graded between 2 and 3 (10-50%) by the end of the summer in 2005 and 2006. The most tolerant apricot cultivars were Budapest and Mandulakajszi while the most susceptible ones were 'Magyar kajszi' and 'Piroska'. Assessments made on plum showed that most of the plum cultivars were tolerant or lowly susceptible to P. rubrum such as 'Ageni', 'Althann ringló', 'Bluefre', 'Cacanska najbolja', 'Silvia', 'Ruth Gerstetter', 'Tuleu gras' and 'Utility'. The most susceptible plum cultivars to P. rubrum were 'Besztercei clones' and 'Debreceni Muskotály'.
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Agronomic and alimentary evaluation of elder (Sambucus nigra L.) genotypes selected from natural populations of Hungary
49-52.Views:140The black elder (Sambucus nigra L.) is a native plant in Hungary represented by extended and very variable populations. Cultivation of elderberry started during the late 90-ies because of the growing interests of the processing industry. High anthocyanin content, nutritive value of the berries and aromatic compounds of the flowers have been the esteemed constituents.
At the moment, there are about 3000 hectares elder plantations in Hungary, which is more than of any of the other European countries. Unfortunately, the cultures are planted to the Austrian selections of Haschberg, in spite of the fact that about 10-15 other selections of other foreign countries have been registered and planted elsewhere. In addition to that, the wild population of Hungary may offer a precious opportunity of further selection. Since 1970, Aladár Porpáczy at Fertőd and the Department of Fruit Growing of the former University of Horticulture in the 1980-ies started the selection in Hungary too.
The present study deals with 7 genotypes, their morphology of berries and inflorescences. Results are concentrated on four genotypes: Szcs1, Szcs-2, Szcs-3 and Szcs-5, which are all earlier ripening than the Haschberg varieties, and are superior in characters of fruit and inflorescence.
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Differences of pollen and pollenkitt attractiveness of some cultivated and ornamental apples for honeybees
145-150.Views:124Differences in the attractiveness of pollen according to plant families and species for the honeybees had been examined by researchers, but pollen samples of cultivars were not tested yet. This examination attempts to evalu2te the differences in attractiveness of pollen of some cultivated and ornamental apples to honeybees. We applied biotest with equal amounts of hand collected pollen samples and by a nucleus of bees with brood. The evaluation was based on the number of visitation by foraging honeybees on the samples during the time of the experiment which was determined. Pollenkitt samples were also tested in a separate experiment.
The data were analysed by variance analysis and significant differences were found according to the number of bee visitation in the attractiveness of the pollen and pollenkitt samples of apple cultivars.
The visualisation of pollenkitt was done by light microscope and SEM.
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Maceration affects mineral composition and pH of wines
25-29.Views:245Mineral composition of wines is affected by many ecological and technological factors. These variables are mostly discussed focusing on certification of origin and human health. This paper gives data on possible changes in mineral composition and pH of wines due to 4 hours skin maceration (1st trial) and fermentation sur marc (2nd trial). Experimental site is situated on acidic sandy soil in middle east Hungary. The variety collection was established in 2003 with own rooted planting material in 3x1 m spacing, trained for single curtain training
system. Mineral composition of wines was determined with ThermoFischer Scientific iCAP 6300 ICP-OES, pH was measured with pH10pen (VWR International) in field, and with SevenEasyTM pH meter (Mettler Toledo) in laboratory. 1st trial with 9 PIWI white wine grape varieties pointed to demonstrate effects of skin maceration, which is abundantly used to elevate aroma content. 2nd trial with the use of ‘Medina’ red PIWI grape variety aimed to demonstrate effects of double pasta skin maceration in rose and red wine technology. Data of 1st trial show, that K, Cu, Mn and P respective increase with skin maceration, despite Fe show considerable decrease. Data of 2nd trial show, that K, Mg, Mn, P, Sr and B increase with longer skin contact and higher fermentation temperature, despite Fe and Ba decrease with this technology. In regard to pH, data show, that skin maceration and fermentation sur marc increase K content with about 30-70% respectively, withstanding that pH also increase with a considerable 0,4-0,5 value. K content can be higher in the end product, despite to earlier higher level of tartrate formation. An attention should be driven to lower level of tartaric acid and consequently higher pH characteristic for wines produced with the application of skin maceration or fermentation sur marc. -
Importance of boron in fruit nutrition
39-44.Views:273Boron (B) is an essential micronutrient in plants especially in fruits. Despite of this fact there are very few information about its application, uptake and symptoms in Hungarian fruit growing sector. Nowadays we should consider the effects of weather conditions on soil B availability increasingly according to the climatic anomalies. Identifying of internal and external symptoms of plant parts (leaf, fruit) is help for growers to recognize the deficiency and excess symptoms in time. Methods and application rates of boron fertilization provide further information for growers to achieve qualify-oriented fruit growing among Hungarian conditions. The aim of this minireview is to focus on the importance of boron in fruit nutrition.
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The effect of day and night temperatures on apple skin colour formation
21-25.Views:205The colour of fruits is considered to be an important quality indicator. Saleability greatly depends on how well covered the colour is of the specific type of fruits. It is a well-known phenomenon by growers that apples get nicer colours in one year while in other years the basically red and green colour cultivars can be differentiated only by morphological characteristic features. Cover colour is one of the phenometric variables and it is a well-known fact that significant differences can be experienced year by year. The experienced oscillation can be the cause of inappropriate water- and nutriment supply, however it can be the result of some kind of plant disease, extremely high or low temperature, setting rate above the average and outstanding fruit density. In the present examination it is postulated that the degree of cover colour is mostly influenced by day and night temperature. Therefore, our study aims to find out whether it is true or not. Cover colour belongs to those phenometric characteristic features, only the final value of which is taken into consideration; due to their nature of establishment or forming time it seems useless to follow closely the change in the time of vegetation. However, determining the start of colouring and knowing the dynamics of full colouring could carry very important information for growers. If it is possible to determine the curve describing the time change of colouring, we have a possibility to estimate it by means of enviroment variables. So it is also possible to model pigmentation in the future. Knowing this, colouring irrigation could be made more efficient in the future. For this, as a first step, it is inevitable to find out what the relationship is between the main meteorogical variables, namely day and night temperature and the difference between day and night temperature, and colour cover. In this study we summarize and show these interrelations.
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Alternate bearing of 'Golden Reinders' and 'Summered' apples
77-85.Views:203The aim of the present study was to study the effect of biennial bearing (irregular yields) on the generative production of apple cultivars 'Golden Reinders' and 'Summerred' on M.9 rootstock. The observations were made at Nagykutas in West-Hungary for four years. The authors have studied the flowering time, flower density, fruit density, fruit drop, seed content, yielding and fruit quality in the on-year and off-year. Based on the results, it can be stated that the alternation does not cause a significant change in the flowering time of cvs. 'Golden Reinders' and `Summerred': the difference between the flowering time of trees in the on-year and off-year period was 0-1 day. However, there were significant differences in the flower density. 'Golden Reinders' proved to have a weaker tendency to alternation similarly to the statements of the literature. Alternation (off-year) was observed only in three years from the studied four years. While in the case of `Summerred', strong alternation was observed in all four years. In fruit density, there were differences among the cultivars and among the different cycles of biennial bearing. Fruit density (and its opposite, fruit drop) changed inconsistently in the period between flowering and harvest. In the case of 'Golden Reinders' and 'Summerred' 2 and 4 fruit drop periods were detected, respectively. In the off-year, the different periods were less distinct, in most cases they were overlapping each other. The dynamics of fruit drop was related to seed content per fruit. The lower the seed number was, the higher the degree of fruit drop was. In both the high- and off-year cycles, the number of seeds in fruits on the tree and on the ground increased with time. In the yield parameters (fruit number, fruit load, yield efficiency), the differences were greater among the yields of trees in the high- and off-year cycles for 'Summerred'. The fruit quality parameters were greatly influenced by the fruit load of the trees in the different alternation cycles. In general, it can be stated that fruit mass, diameter and height were lower on trees in the on-year. A similar trend could be observed in flesh firmness, cover colour and dry matter content, but the differences were smaller. 'Summerred' was more sensitive to the differences in fruit load.
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Evaluation of potential of fruit weight and fruit width and their interrelationships in the set of apricot genotypes
47-53.Views:98Within the period of 1994-1999, variability of fruit weight and width was evaluated in altogether 24 apricot genotypes. It is concluded that the genotype and climatic conditions of individual years are the factors causing variability in these two parameters of apricot fruits. Variability of fruit weight was significantly higher (approximately 3-times) than that of fruit width. When evaluated on the base of their width, 75.0% and 95.8% of apricots were classified into the groups of extra and first quality, respectively. As genotypes with the maximum fruit width (i. e. above 50 mm) the following cultivars were classified: 'Velkopavlovicka LE-6/2', 'NJA-1', 'M 45', 'M-25' and lednicka (M-90-A)'. The value of fruit width (in mm) corresponded with its weight (in g) only within the range of 40 — 45 mm. With the increasing and/or decreasing size of apricot fruit the changes in fruit weight were more pronounced than in those in fruit width. Within the set of genotypes under study, this relationship may be expressed by the equation y = 0.1234 — 7.6605 + 152.76; the corresponding values of correlation coefficient and coefficient of curve determination are r = 0.95-H- and R2 = 0.959.
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Measuring the vibration of a brush cutter in different operation modes
95-98.Views:168The vibration load of a hand-held machine depends on many factors not defined in the ISO 5349:2001 standard about the measurements and evaluation of human exposure to hand-transmitted vibration. In this study, the effect of different operation modes on the vibration emission of a brush cutter was investigated. The frequency weighted r.m.s. acceleration was measured at the front (left) and rear (right) handle in three orthogonal directions according to ISO 5349 (2001). Two set of measurements were performed with three subjects for
idling and cutting operations. In addition, the acceleration was measured with two holding positions, i.e. the cutting head is tilted by 45˚ to the left and tilted by 45˚ to the right. The standard vibration evaluation method, with the cutting head parallels to the ground, significantly under-estimated the vibration emission of the tilted tool to the left and right. The results suggest that the use of different holding positions would improve the reliability of the standard method of assessing the vibration of hand-held tools. -
Assessment of soil characteristics in orchard
11-14.Views:192The 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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The effect of nitrogen supply on specific yield and fruit quality of apple (Malus domestica Borkh.)
7-21.Views:169The aim of the present study was to determine the effect of nitrogen supply on yield and fruit quality of apple cultivars and to explore the relationships between canopy density and the different fruit quality parameters.
The experiments were carried out at Kálmánháza, in Eastern Hungary in a private orchard in 2003-2004. The response of four apple cultivars ('Elstar', 'Gala Prince', 'Granny Smith', 'Idared') to different nitrogen dosages was studied. The assessed and calculated indices were: yield, fruit diameter, fruit height, shape index, fruit mass, firmness, dry matter content and colouration. The results indicated that nitrogen fertilization has a significant effect on the yield and fruit quality of apple cultivars. The calculated specific yield values were reduced by the application of nitrogen via the increase in the volume of the canopy. An opposit trend was observed for fruit diameter, fruit height and fruit weight, which increased with increasing nitrogen supply. The reduced shape index caused flattening of fruits.
However, the improvement of fruit quality via increasing nitrogen dosage is only virtual, since these dosages increase the fruit size, but firmness, dry matter content and colouration are diminished, which decreases the value of the fruits on the market.
The authors also studied the relationships between canopy density responsible for assimilation and light supply of the fruits and the different fruit quality parameters. The closest linear inversely proportional relationship was found in the case of colouration. There was a negative linear relationship between canopy density and firmness or dry matter content. The relationship between canopy density and fruit mass could be described by a quadratic polinomial function.
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Experiments on the Resistance or Pepper Cultivars to Macrophomina phaseolina
74-75.Views:122The ashy stern blight of pepper (Capsicum annuum) is often caused by Macrophomina phaseolina. Serious wilt disease occurred between 1994 and 1996 of pepper plants in Hungary. In 1996-98 screening experiments were made on many pepper cultivars. Culture (Knopp) solution experiments, pot experiments, greenhouse and field trials were carried out. We determined the incidence of disease by visual examinations, testing on PDA culture, and light microscope. There were significant differences in susceptibility of cultivars and breeding materials.
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Summer pruning of sweet cherry trees and an inquiry of winter frost damages
41-44.Views:245One of the most demanded research projects is the intensification of fruit production. The use of dwarfing stocks is a moderate solution as their effect is scarcely satisfactory. Climatic conditions of Hungary are continental in Eastern Europe, where Atlantic and Mediterranean effects are interacting with the continentals in a kind of basin with characters of its own. Capricious meteorological episodes are often disturbing the security of development and fruiting of trees:
• winter frosts are damaging the cambium and fruiting structures of trees
• late spring frosts destroy cambium and flowers
• early autumn frosts hurt the leaves
• excessive precipitation impairs the growing fruits
• drought periods during the summer caused water stress disturbing water husbandry.Vigorous stocks still prevail in the practice, and they ought to withstand challenges of weather hazards. The strong vigour of plants delaysthe process of senescence and the tendency of getting bald, and regeneration of plants is a sign of vitality. In present research, the trees have been trained on vigorous Prunus mahaleb stocks. Summer pruning was one of the important tools of intensive growing techniques. They were compared with traditional techniques and with plastic foil protected trees observing the vegetative as well as generative growth of them.
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Irrigation of pear (A review)
65-73.Views:178The plantation of intensive growing orchards and steady increase in yield is essential to return the growing cost by sale. Seasonal crop fluctuation of pear is increased by the frequently occurrence of drought and climatic changes. This study reviews genetic and growing factors determined the alternancy of pear and present the new knowledge concerning on water saving irrigation techniques. Use of dwarfing rootstocks, root pruning, branches pruning and new water saving irrigation make the changes in vegetative and generative growth that successfully improve the alternancy of pear growing. According to publications BA 29 of clonal quince rootstocks exhibited the best protection mechanism against to drought. Regulated deficit irrigation (RDI) applied during rapid shoot growth and slowly fruit growth result a decrease in shoot growth and 60% of water saving in pear orchard while there was no influence on harvested yield. Partial rootzone drying (PRD) microjet irrigation applied in pear orchard result 23-52% of decrease in water use, however concerning explorations are contradictory. Further investigations need to improve the efficiency of new irrigation technology adapted pear varieties based on monitoring of soil water status and measurement of stem water potential as stress indicators of plants.
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Fungicide resistant Trichoderma strains causing compost infection in shiitake production
67-70.Views:118Trichoderma infection represents the major problem of shiitake production in the growing house of the Research Institute at Kecskemet. Heavy infections occur mainly on the compost before spawn run. All the isolated strain belongs to the species Trichoderma harzianurn, but morphology of the colony indicates that there are more strains liable for the infection. Source of infection remained unclear but the Trichoderma strains can be considered as weed moulds rather than true pathogens of shiitake. All the Trichoderma isolates showed unusual high degree of resistance to fungicides.