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Parameter optimization of an inductively coupled plasma mass spectrometer for measuring arsenic and selenium
81-85Views:143In the last decades, an increased interest has evolved in arsenic and selenium. The aim is to understand the environmental, agricultural and biological roles of these elements. In the case of arsenic, the major reasons are the relatively high concentration of arsenic in marine biota (mg kg-1) and the arsenic contaminated drinking water bases of some Asian countries, as well as Hungary. The toxicity of higher level selenium content is also known; nevertheless, selenium is essential for several biological functions. Considering its essentialness, in our country, the insufficient selenium intake rate causes a lack of selenium. Measuring the concentrations of these elements provides crucial, but unsatisfactory information, as the speciation, i.e. the form of an element presented in a sample is also required.
In both cases, the most suitable method to determine concentration is inductively coupled plasma mass spectrometry (ICP-MS). Our objective was to optimize the variable parameters of the ICP-MS to attain the lowest (the best) detection limit. For this purpose, we investigated the effect of parameter change on net signal intensity and relative signal intensity. With the optimized parameter settings, the limits of detection for arsenic and selenium were determined, which are 0,032 ng dm-3 for arsenic, and 0,097 ng dm-3 for selenium. -
Evaluation of tree measurements after the reconstruction of tree-row system in five narrow streets of Debrecen
217-222Views:149Viable urban environment is largely dependent on the size, condition and distribution of urban green spaces within and around cities. Treerows in streets are one of the most essential elements of urban green spaces. The aim of this study was to evaluate tree taxa compositions and lifespan values of trees in tree-row system with special reference to five narrow streets (Garai, Jókai, Tanító, Csokonai and Zsák) of Debrecen. Tree numbers, tree taxa and the origin of tree taxa were determined in two years (2009 and 2017). As a next step, six selected taxa (Pyrus calleryana 'Chanticleer', Acer tataricum, Sorbus intermedia 'Browseri', Magnolia kobus, Acer platanoides 'Olmsted', and Crataegus x lavalleei 'Carrierei') were further estimated for the following lifespan parameters: i) trunk diameter (cm), ii) tree crown size (m), iii) trunk status (in 0–5 grades), iv) tree crown status (in 0–5 grades), v) estimated tree viability (in 0–5 grades), and vi) tree value in Ft. Our results showed that the numbers of tree taxa were 9 and 11 in 2009 and 2017 as well as an overall 279 and 282 trees were evaluated in 2009 and in 2017, respectively. More than 60% of the trees were native or similar to native taxa. The largest and the lowest trunk diameters were achieved for Pyrus calleryana 'Chanticleer' and for Acer tataricum, respectively. The largest and the lowest tree crown diameters were achieved for Acer platanoides ’Olmsted’ and for Magnolia kobus, respectively. The best and the worst trunk statuses by 2017 were achieved for Pyrus calleryana 'Chanticleer' and for Crataegus x lavalleei, respectively. The best and the worst tree crown statuses by 2017 were achieved for Pyrus calleryana 'Chanticleer' and for Acer tataricum, respectively. The best estimated tree viability status was achieved for Pyrus calleryana 'Chanticleer' and for Acer platanoides. Overall tree values were 2.73 times higher in 2017 compared to 2009. In conclusion, this study clearly demonstrated the importance of appropriate choice of tree taxa for an establishment of tree-row system in narrow street conditions.
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Fusarium culmorum isolated from rhizosphere of wooly cupgrass (Eriochloa villosa) in Debrecen (East Hungary)
93-96Views:146Wooly cupgrass (Eriochloa villosa) is an East-Asian originated weed species and it has been spreaded worldwide by now. The first occurrence of this species in Hungary was observed and published in 2008 nearby Gesztely village (Borsod-Abaúj-Zemplén county, North-East Hungary) than in the summer of 2011 a significant population was discovered next to Debrecen city (Hajdú-Bihar county, East Hungary).
In 2013 this weed was also reported from Szentborbás village, Somogy county (South-West Hungary). These observations of spreading and its biological features (production of stolons and large number of seeds, moreover herbicide tolerance) indicate that wooly cupgrass (E. villosa) has a great potential of invasiveness, so it may become a hazardous weed not only in Hungary but in all over the world.
The objective of this study was to identify the fungus which was isolated from wooly cupgrass (E. villosa) root residue samples which were collected after maize harvesting on arable land in late autumn, near Debrecen. The identification of the fungus based on morphological characters of colonies and the features of conidia developed on potato dextrose agar (PDA) plates. After the examination of axenic culture we revealed that the fungus from rhizosphere of wooly cupgrass was Fusarium culmorum. Pathogenicity and/or endophytic relationship between the fungus and wooly cupgrass is still uncertain so pathogenicity tests and reisolations from plants are in progress.
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Testing laboratory parameters of compost tea
31-36Views:385During the industrial production of broiler chicken, a large amount of manure is produced, of which easily contained nitrogen content (without pre-treatment) is released into the atmosphere as an air pollutant. In our experiments, we aimed to prepare compost tea, also known as water extract of compost, from pre-treated poultry manure in order to create a product can be utilized as liquid nutrient supply. The poultry manure source was the Baromfi-Coop Ltd. located in Nyírjákó, Hungary, where it was treated by composting. As a result of this pre-treatment of the poultry manure, its nutrient parameters improve and nitrogen is present in a form that is better utilized for plants. Furthermore, this product is suitable for further utilization and also can be the base material for a brand-new product. For this reason the effects of compost/water ratio, incubation time, low oxygen level, and extraction time on the parameters of the resulted product were studied in the frame of developing new soil-life enhancing microbial product, so-called compost tea.
Chemical parameters of the compost used as base material strongly determined the properties of the resulted compost tea, especially the ratio of the various nitrogen forms, their concentration and the salt content. It was found that adding water at a higher rate that means 1/40 and 1/50 mixing ratios results in more cost-effective production. In the experiment the compost tea were held under oxygen-poor conditions, therefore pH of the extractions decreased, which influenced the quality and quantity of their nutrient content.
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Studies of the influences of different N fertilizers and Microbion UNC bacterial fertilizer on the nutrient content of soil
134-140Views:59A field experiment was conducted to examine the effects of different nitrogen fertilizers in combination with bacterial fertilizer on
nutrient uptake of horseradish and plant available nutrients of the soil. Three different N fertilizers, ammonium-nitrate, urea and calciumnitrate
(116 kg ha-1 N) in combination with Microbion UNC bacterial fertilizer (2 kg ha-1) were applied as treatments in a randomized
complete block design in three replications. In this paper we presented the results of soil measurements. The soil of the experimental area
was chernozem with medium sufficiency level of N and P and poor level of K.
Our main results:
The amount of 0.01M CaCl2 soluble inorganic nitrogen fractions, NO3
--N and NH4
+-N and also the quantity of soluble organic-N were
almost the same in the soil. N fertilizers significantly increased all the soluble N fractions. The amount of NO3
--N increased to the greatest
extent and the increase of organic N was the slightest. We measured the largest CaCl2 soluble NO3
- -N and total-N contents in the plots
treated with ammonium-nitrate, the largest NH4
+-N in the plots treated with calcium-nitrate and the largest organic-N fraction in plots
treated with urea.
Bacterial inoculation also increased both soluble inorganic nitrogen forms and also total-N content of soil compared to the control. In
the case of combined (artificial and bacterial fertilizer) treatments we measured lower NO3
--N, organic-N and total-N compared to the
values of plots having only nitrogen fertilizer treatments. On the contrary in the plots with combined treatments the CaCl2 soluble NH4
+-N
content of soil in more cases were higher than that of values with artificial fertilizer treatment.
As a function of calcium-nitrate application increased AL-P2O5 and AL-K2O values were measured compared to control. Microbion
UNC supplement of calcium nitrate yielded also increase in AL-P2O5 and AL-K2O values, till then supplement of ammonium-nitrate fertilizer
yielded a decrease in these values compared to the control.
All nitrogen fertilizers resulted in a significant decrease in AL-Mg content of soil compared to the control. Nevertheless bacterial
fertilizer increased AL-Mg values in any cases. -
The Role of the Digital Terrain Models in the Assessment of Surplus Water Risk at the Szolnok-Túri Plain
47-51Views:96The environmental factors to which surplus water can be assigned (topography, soil, groundwater, vegetation etc.) can be subject to special analysis and the randomness of the occurrences can be limited. The results of these procedures are surplus water risk maps of the areas, which can be utilised in land use planning. The risk map of the research site was created with overlaying digital category maps of the determining factors (hydraulic conductivity, convexity, critical probability of ground water level and land use).
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Ragweed components in honey
65-68Views:155The aim of this research was to prove that the syrup containing ragweed used for feeding the bees was transferred to the honey. To reach this goal we developed a method to analyse the volatile components of the samples. We applied two sample preparation methods. The first one was SPME (Solid Phase Micro Extraction) preparation from the headspace of all of the samples. In the second case only the raw leaves of the ragweed were extracted with n-hexane and dichloromethane to complete the SPME results. The measurements were performed on GC-MS equipment. Chromatograms and data evolution showed that the components of the ragweed were also present in honey so they were transferred by bees.
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Preliminary estimation of the efficacy of Fusarium sporotrichioides Sherb. as biological control agent against common milkweed (Asclepias syriaca L.)
201-204Views:248A study of fungi responsible for severe leaf spots of common milkweed (Asclepias syriaca L.) in the Hajdúság region (East Hungary), Fusarium sporotrichioides and Alternaria alternata were isolated from infested leaf tissues. F. sporotrichioides was the most virulent fungus in pathogenicity tests conducted on healthy leaves of common milkweed plants. Inoculation of common milkweed (A. syriaca) in different growth stages with F. sporotrichioides yielded similar symptoms as the original ones. Spray mixtures containing 1.0×106 conidia/ml gave effective control when common milkweed plants were sprayed until runoff occurred. Laboratory (wet chamber) and field experiments showed that asexual spores of the fungal pathogen, F. sporotrichioides, exhibited bioherbicidal activity against common milkweed (A. syriaca).
More efficient control efficacy was observable on elder plants (at flowering stage) than younger ones. These results initiate that this fungus may be a biocontrol agent for controlling this invasive weed but should clarify its hosts because it could infect cultivated plants as well.
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Random regression models for genetic evaluation of performance of the Hungarian show-jumping horse population
87-91Views:125The aim of the study was to estimate genetic parameters for show-jumping competition performance using random regression model. Show-jumping competition results collected between 1996 and 2009 were analyzed. The database contained 272 951 starts of 8020 horses. Identity number and gender of the horse, rider, competition date, the level of the competition and placing were recorded in the database. Competition levels were categorized into five groups. Weighted – competition level used – square root transformed placing was used to measure performance of horses. The random regression model included fixed effects for gender, year and place of competition, and random effects for rider, animal and permanent environment.
Later performance of show-jumping horses measured with weighted square root ranks is less influenced by rider and permanent environmental effects than performance at the beginning of a horse’s sporting career. Heritability increased continuously from 6.3 years of age (2296 age in days), values were in the range of 0.07 and 0.37. Higher heritability was found in later ages. Weak genetic and phenotypic correlation was found between the early 4–5–6 years of age and older (7, 8, 8+) age classes. From 8.5 years of age (3132 days old) there were strong genetic and phenotypic correlations between neighboring age groups. For the same age classes moderate and strong genetic and phenotypic correlation was found. Genetic correlation between 13.5 years of age and older horses was very strong.
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Characterization of two rust fungi related to biological control concept in Hungary
195-199Views:274Weeds cause serious problems in agriculture on a global scale. These plants reduce yield and the quality of crops by competing for water, nutrients and sunlight. The improper or excessive usage of herbicides have led to development of resistance in some weed species while contaminating the environment; therefore, biological control has an increasing role as an alternative method for controlling special weed species.
The aim of this study is to make a brief review of biological control of weeds by pathogens and to characterize two rust fungi (Puccinia lagenophorae and Puccinia xanthii) which are broadly examined recently in a biological control concept and have been found on their hosts, such as common groundsel (Senecio vulgaris L.) and common cocklebur (Xanthium strumarium L.), two common and difficult to manage weeds both in horticultural and agricultural lands also in Hungary.
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Investigation of host-specificity of phytopathogenic fungi isolated from woody plants
155-160Views:138Host-specificity is an important characteristic of fungal pathogens. Changing climate could create more appropriate environmental conditions for phytopathogens, thus formerly host-specify fungi could be able to colonize new hosts. Noxious plant pathogen fungi, which can infect several plant species are well-known worldwide. These genera may expand their range of hosts because of the appearance in new geographic areas due to climate change. This new exposure can result in serious problems in agriculture because of the lack of immunity. The susceptibility of apple tree was studied through testing pathogenicity in vitro with species isolated from walnut twigs and nuts, and identified by ITS sequences. Three of four tested species, Botryosphaeria dothidea, Diaporthe eres and Diplodia seriata colonized and necrotized the infected apple branches, while Juglanconis juglandina was not able to infect the twigs. Members of Botryosphaeriaceae were the most virulent, causing the largest lesions in the fastest way. This experiment draws attention to the threat of new host-pathogen connections, which can arise because of the favourable weather conditions and can spread between neighbouring cultures.
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Review of the biology of plant psyllid (Cacopsylla pruni, Scopoli 1763), and its role in the spreading of European stone fruit yellows, ESFY-phytoplasma with Hungarian data
25-33Views:295The European stone fruit yellows (ESFY) phytoplasma disease caused by pathogen ’Ca. Phytoplasma prunorum’ induces serious damages in cherry, sour cherry, peach, and apricot orchards mostly in Europe. Its known vector is the plum psyllid (Cacopsylla pruni). Many articles report on the biology (morphology, taxonomy, life cycle etc.) and the method of transmission of the pathogen by the vector, and the possibilities of their control. This paper reviews our knowledge about the vector, and summarises the results of an inland research carried out in a northeastern Hungarian apricot orchards. Our goal was to show some important data for the farmers or anyone who is interested in this disease and its vector. And give some known method that we can protect our orchards against them to prevent the appearance of the disease. As the psyllid that became infected with the pathogen can hold its infectionous capacity during their lifetime, it is very important to have enough knowledge about their lifecycle, that we can determine the right time and method to control them. We also have to know how to identify them; therefore, this paper lists several important data which can be helpful. The most important keys of identification are their wing color, which dark borwn in the apex and brown is in the remaining part of the forewing. The length of the antennae is also an important factor, since other genuse’s species have longer antennae than twice the width of the head. C. pruni has as long antennae as twice the width of the head. They return to Prunus species in early spring and we have to protect our orhards in this period against them. We have to use preparations with a knock down effect on them to prevent the inoculation of the pathogen into the trees in our orchards.
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Evaluation of Hungarian show-jumping results using different measurement variables
81-85Views:145The aim of the study was to compare different fitted models for show-jumping results of sporthorses and to estimate heritability and repeatability value. Show-jumping competition results collected between 1996 and 2011 were analyzed. The database contained 358 342 starts of 10 199 horses. Identity number, name and gender of the horse, rider, competition year, the level and location of the competition and placing were recorded in the database. To measure performance of horses, placing, number of starters and competition level were used. Competitions were categorized into five groups based on their difficulty level. The used repeatability animal model included fixed effects for age, gender, competition place, year of competition (and competition level in case of non-weighted measurement variables), and random effects for rider, animal and permanent environment effect. Variance components were estimated with VCE-6 software package. The goodness-of-fit of the models was low and moderate. Heritability and repeatability values were low for each measurement variables. The best goodness-of-fit model the weighted square root of placing resulted the highest heritability and repeatability value h2=0.074 and R=0.296.
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Evaluation of Hungarian Sporthorse mare performance tests
83-87Views:76Results of the Hungarian Sporthorse mare performance tests were evaluated. Data from the period of 1993-2009 were used, covering
scores of 618 3-year-old and 310 4-year-old mares, 109 of them were tested at both ages. Seventeen traits were scored on the tests, which
covered ten conformational, three free jumping performance and four movement analyses traits, respectively. Breeding value estimation was
based on BLUP animal model. Test year, age and owner were included in the model as fixed effects. Variance components were estimated
with VCE-6 software package. Heritabilities ranged from 0.32 (frame) to 0.50 (saddle region) for conformation traits, from 0.39 (jumping
style) to 0.49 (jumping ability and jumping skill) for free jumping traits and from 0.20 (walk) to 0.48 (canter) for movement analysis traits.
Breeding value indexes were constructed for each trait group. Conformation index was computed based on the weighted scores of the
breeding values of conformational traits. The conformational score scales were used as weightings. Free jumping and movement indexes
contain the proper breeding values with equal weights. A total index was also constructed using conformation index, two times the free
jumping index and two times the movement index. Each breeding values and breeding value indexes were presented with the mean 100 and
standard deviation of 20 for the easier understanding. -
Distribution of the American grapevine leafhopper (Scaphoideus titanus ball 1932) in west Romania
127-130Views:155The vector of Grapevine Flavescens Dorée phytoplasma, the American grapevine leafhopper (Scaphoideus titanus) has been in Europe since 1924. In Romania, the first populations were detected in 2009 in the central, eastern and southern part of the country. Later, the leafhopper was found also in West Romania in 2014. In 2015 and 2017, altogether, 14 sampling sites were studied in two vine regions of this area. The Scaphoideus titanus could be detected in 10 of them with relatively small abundances. During the studies, the yellow sticky traps proved more effective methods than sweep netting. To prevent vineyards from disease, we should do everything against the vector from prevention to chemical protection.
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Nest-site preference of Hooded Crow (Corvus cornix L.) in Debrecen, Hungary
13-17Views:119In the past decade, the population of the Hooded Crow has shown significant growth in Debrecen, Hungary. The aim of this study was to become acquainted with the nest-site selection behavior of Hooded Crows in urban spaces. While our research revealed that the Hooded Crow is not particular when it comes to selecting among tree species for nesting, we did notice differences regarding nesting height. Hooded Crows living in the city build their nests higher up than those living outside Debrecen’s city limits. We also discovered a slight, insignificant difference between nesting heights and tree species, which is probably due to the different characteristics of the given tree species. As for nesting heights, we found that in typical urban habitats there were no relevant differences. However, when we compared these habitats in pairs, it came to light that nesting heights -when comparing solitary trees - wood segments and tree rows - wooded segments- did show significant differences, which can be explained by the various conditions provided by the habitats mentioned.
In summary, the following results emerged from our research:
1. The Hooded Crow prefers approximately the same nesting heights in all kinds of habitats, urban environment and tree species.
2. The nesting height does not significantly depend on the habitat itself or on the tree species. -
Establishing biotic stress tolerance of maize (Zea mays L.) by measuring hydroxamic acid contents
107-112Views:183Cyclic hydroxamic acids are the most considerable secondary metabolites in grasses and their main task is to protect these species from pathogens and pests. The cyclic hydroxamic acid content and common smut susceptibility were examined in our experiments. 27 maize hybrids were used for experimental plants in a climate room, where the plants were grown on a nutrient solution. An infiltration method was used for the inoculation of the plants. The total quantity of cyclic hydroxamic acids was determined and the ratio of infected plants and the ratio of inhibition was determined, too. Based on our results, on the basis of all hybrids’ data, the total hydroxamic acid content of the infected plants was higher than in the control. On the level of individual hybrids, only 9 of them had higher cyclic hydroxamic acid content in the case of infection. Increase in cyclic hydroxamic content induced by the fungus in this case is a tool for the fungus to suppress other pathogens and pests. Amongst the hybrids’ cyclic hydroxamic acid contents, significant differences were detected in the control and in the infected treatment, too. The so-called “sweetcorn” hybrids showed high level of cyclic hydroxamic acid content. According to the differences amongst hybrids, homogenous groups were created which groups differed in the case of control and infected treatment, because of the difference in increase of cyclic hydroxamic acid content. The examined hybrids showed different levels of infection and different rate of growth inhibition for the effect of inoculation. According to the infection caused damage hybrids were ranked. Infection caused notable damage for hybrids Prelude, Desszert 73, DKC5276 and DK440.
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Chromatometric comparison of Eurasian Collared Dove (Streptopelia decaocto) and Feral Pigeon (Columba livia domestica) feathers
19-22Views:176Chromatometric examination of the plumage of birds is a poorly researched topic. We have approached this issue in primarily aspect of differences in plumage of species. Moulted feathers sample collection method has been increasingly used. Reliable identification of feathers becomes an increasingly important issue, hence need for an exact measurement-based methodology. Eurasian Collared Dove (Streptopelia decaocto) and Feral Pigeon (Columba livia domestica) primary, secondary and tail feathers were studied. Chromatometric parameters of feathers were measured in CIELAB color system and then statistical analysis (Independent samples t-test, Descriptive Statistics, Discriminant Analysis) was performed to compare the two species. Instrumental measurements has been confirmed the high similarity between colors of the two species, however species specific differences were also found. Lightless (L*) value were significantly characteristic of particular species, while the red/green (a*) and yellow/blue (b*) value had lower Predictive Power. We identified feathers and the variables which useable to separate the two species and determined the associated Confidence Intervals of these values. Our results may draw attention to a new potential direction for exact identification of the moulted feathers during sample collection.
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The marigold (Calendula officinalis L.) drug essential oil agents change under different fertilization settings in small plot trial
57-60Views:158During our research we investigated the marigold's (Calendula officinalis L.) nutrient requirements with different fertilization setting in small-plot trial. We measured SPME (Solid phase microextraction) and GC-MS (gas chromatograph-mass spectrometer) we examined the effects of the different fertilization settings for the herb's main active ingredients of essential oil's percentage.
Based on the results, it was concluded, the essential oil agents' percentage breakdowns significantly depending on the cropping technologies. Besides that it is possible, based on Pearson's correlation test the marigold essential oil agents relationship can also be a major factor.
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The significance of local meteorological stations in research planning
87-91Views:186The goal of research planning is to optimize human and material resources while maximizing efficiency. If there are databases that can be used as a substitute for own data collection, effective research can be facilitated by reallocating resources. In the case of environmental studies, the knowledge of the climatic conditions of the study period is known to be a key factor in research planning process.
In the present study, the data of our meteorological station in our research area (known as “Szamárháti Tanya”, Kesznyéten, Hungary) was compared with the measurements of meteorological stations operated by the competent water authority. Stations were taken into the study within a 10 and 20 km radius over a period of 21 months, to determine which provided more relevant data from the area.
During the evaluation of results, the relationship between the local and regional weather stations were determined, and deductions were made from the obtained results to support the decision which of the targeted investigations could be of greater benefit.
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Measuring of nitrogen leaching using ceramic suction cups at different locations
10-17Views:71Ceramic suction cups were used for the measurement of N-concentration in soil solutions under different soil and climate conditions in both field experiments of Rostock University and Agricultural University of Debrecen (Hungary). Depending on the soil utilisation the change in the N concentration of the soil solution can be proved on both sites.
The experimental field of Rostock University can be characterised by its high groundwater table. The nitrogen concentration of soil solutions in the different soil layers were determined by the trend downward of water. In the dactylis (Dactilis glomerata) experiment, the quadruple treatments involved the following: with and without N-fertiliser, with and without harvesting, respectively. In the lower soil layers, the least rising N concentrations were established in case of the treatment without N-fertiliser combined with harvesting. The nitrogen leaching calculated from the infiltrated water quantity and the nitrate N concentration increased in the following order: without N-fertiliser, with harvesting < without N-fertiliser, without harvesting < with N-fertiliser, with harvesting << with N-fertiliser, without harvesting.
The field experiment site of Debrecen can be characterised by a low groundwater table. The effect of N-fertilisation on the nitrate-N concentration of soil solution in the soil layers can be stated unanimously. Permanent nitrate-N leaching cannot be established due to the water upward movement under semiarid climate conditions. Intermittently transfer of nitrate-N between the soil layers is probable in cases of remarkable precipitation. -
Some population genetics parameters of the present Hungarian Hucul Horse population
15-22Views:150We examined the Hungarian population of the Hucul horse breed, under genetic protection, based on population genetic indicators until the year 2014 included. The evaluation was performed using the Endog programme based on the following indicators: inbreeding coefficient, average relatedness, the maximum number of generations, the number of full generations traced and offspring number. Our findings were as follows: the average inbreeding coefficient of the total population was 5.99%, average relatedness was 11.82%, the maximum number of generations was, on the average, 16.04%, and the number of full generations traced with reference to the whole population was 4.15% on the average. 40% of the whole population (723 individuals) did not have any offspring; 42% (759 individuals) attained an offspring of 1 or 2, while 3.4% (88 individuals) had a surviving offspring of 3. The highest offspring number according to the national database (92) was attained by one stallion.
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Allelopathic effect of invasive plants (Eriochloa villosa, Asclepias syriaca, Fallopia x bohemica, Solidago gigantea) on seed germination
179-182Views:257The aim of this study was to determine the allelopathic potential of invasive species woolly cupgrass (Eriochloa villosa), common milkweed (Asclepias syriaca), bohemian knotweed (Fallopia x bohemica), and giant goldenrod (Solidago gigantea Ait.) on germination crop (Lepidium sativum L.). Experiments were conducted under laboratory conditions to determine effect of water extracts in petri dish bioassay. Water extracts from fresh biomass (leaves and stem) of invasive weeds in concentrations of 4 and 8 g/100 ml were investigated. All invasive plants showed allelopathic effect on germination. In giant goldenrod stem water extract experiment, allelopathic effect was less pronounced.
The cress germination was greatly suppressed with the woolly cupgrass, common milkweed and the giant goldenrod. The experiment showed that the seed germination depended on the concentrations and the plant material used (leaves and stem).
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Water managed properties of apple and pear trees based on lysimeters
129-132Views:135A significant proportion of the aboveground green and dry weight of the plant is constituted by foliage. The canopy is an important factor of plant growth. On the one hand, the canopy absorbs solar energy, which is necessary for photosynthesis; on the other hand, it accumulates the nutrients absorbed by the roots, and most of the water-loss occurs through the foliage. 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 the 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. From the examined trees were made a 3D depiction, which show the shape, branching and the location of trees.
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The Effect of Tillage Treatments on Soil Temperature at Planting and on Corn (Zea mays L.) Yield
40-44Views:92The effect of soil temperature was evaluated on the yield of the Occitan corn hybrid at a depth of 5 cm. We examined this effect on the time required from planting to emergence for three average durations: five, ten and fifteen days, all calculated from the day of planting. Winter plowing (27 cm), spring plowing (23 cm), disc-till (12 cm) treatments and 120 kg N per hectare fertilizer were applied. As a result of our analysis, we determined the post planting optimum soil temperatures for various time periods. The average soil temperature for a time period of 15 days post planting is the most usable for determining actual yields, followed by ten days, with five days proved to be the least usable (winter plow R2 = 0.86, spring plow R2 = 0.87, disc-till R2 = 0.64).