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Sensitivity of methods for estimating reference evapotranspiration
Published September 18, 2014
51-56

...5); font-variant-ligatures: normal; font-variant-caps: normal; -webkit-text-stroke-width: 0px; text-decoration-style: initial; text-decoration-color: initial;">The knowledge of the evapotranspiration of natural ecosystems and plant populations is of fundamental importance in several branches of science, research topics and practical uses. Nevertheless, the harmonization of the large number of methods and the changing user needs often causes problems. Sensitivity analysis of 10 ET0 estimation models and model variants was performed. Magnitude of the obtained outputs and the changes triggered by each atmospheric parameter were evaluated. The objective of the analyses was to get to know the sensitivity of the different models and to select the most accurate and the most suitable ones for adaptation to local circumstances. Therefore, it becomes possible to achieve as high accuracy as possible in applications which need ET0 estimation.

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Preliminary studies on in vitro sensitivity of Venturia inaequalis populations to some fungicide active ingredients
Published December 16, 2012
165-168

Aim of this study was to investigate the sensitivity of conidia of Spilocaea pomi to main fungicide active ingredients (cyprodinil, pirimethanil, fluquinconazole, tebuconazole, difenoconazole, dodine és trifloxistrobin) at dosages of 0.5, 1 and 2 times incubated in vitro at 24 and 48 hours collected from three integrated apple orchards. Result...s showed that degree of conidial germinations at the fungicide treatnemts decreased in the order of dosages of untreated, 0.5, 1 and 2 times. Considerable conidial germination was observed at higher dosages of some fungicides (e.g. groups of strobilurines and EBI) which confirmed the possibilities of sensitivity reduction of Spilocaea pomi to some funigicides in the sampled Hungarian apple orchards.

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The role of the hybrid-specific technological recommendations of maize in precision crop production procedures
Published November 13, 2012
297-302

The necessity of application of hybrid specific crop production technology has been confirmed not only by trial results but also by the experiences gained from the agricultural practice. For this reason it is essential to test and collect data in field trials about the specific agronomic traits of the corn hybrids belonging to different maturit...y groups and genotypes. Corn hybrids are tested for their responses to sowing time, plant density and fertilizer supply; sensitivity to herbicides; and lately, the resistance to the damages caused by the larvae of corn root worm. Last but not least, mention should be made of the differences in the responses of the corn hybrids to the damages caused by drought stress. Based on the trial results, suggestions for the hybrid specific corn production are compiled and made public for the experts and farmers engaged in corn growing. Corn hybrids may deliver maximum yields on the impact of specific crop production technology only in case if it relies on carefully done general production technology including soil cultivation, seed bed preparation and weed control. Similarly, precision crop production technology may advance the yield increase in economic way if it is constantly drawing on the source of research results.

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Managing risk using real options in company’s valuation
Published April 8, 2014
125-132

The valuation of company is very important because provides information about the current value/situation of company, and through this, provide the opportunity of choosing the best company’s growth alternatives. The future strategic decisions are characterized by lack of knowledge, information, so all measures of company’s growth are closel...y linked with uncertainty and risk. The company’s valuation process is also related with uncertainty and risk. The risk may result both from the assessed assets and the technique used. In literature, we could find three approaches for risk management: capital budgeting based method, methods based on portfolio analysis and real options approach of risk management. Among them, the real options based methods is the most revolutionary approach for risk management. The advantages of the method, consists in the fact, that the process of establishing strategic decisions integrates the possibility of reversibility, delay and rejections, which isn’t it possible at two previous methods. The method also takes into account the total risk of company, so both the company-specific and systematic risk. In this study, I have used one of the best-known real option based method, the Black-Scholes model, for determining the option’s value. Determination of option value is based on the data of enterprise, which was tested Monte Carlo simulation. One of the basic assumptions of the Black-Scholes model is that the value of option is influenced by several factors. The sensitivity of option’s value could be carried out with so-called “Greeks”.. In the study the sensitivity analysis, was carried out with indicators Delta (Δ), Gamma (Γ) and Vega (ν). The real options based risk management determinations were performed in the R-statistics software system, and the used modules are 'fPortofio' and 'mc2d'. By using of real options method, I have calculated the average value of company capital equal with 38.79 million. By using simulation was carried out 1000 runs. The results of this show a relatively low standard deviation, small interquartile range and normal distribution. In the calculation of indicator Delta, could be concluded the value of company moves in 0.831 proportion to the price of options, the standard deviations of index is low, so the real option based method could be used with success in company’s value estimation. The Gamma index shows the enterprise value is sensitive just for large changes. The result of Vega reflects the value of option, so the company’s value volatility, which is small in this case, but this means a volatility of value. In summary, we can conclude that the call options pricing model, well suited for the determination of company’s value.

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Assessment of Environmental Susceptibility/Vulnerability of Soils
Published December 10, 2002
62-74

Soils represent a considerable part of the natural resources of Hungary. Consequently, rational land use and proper soil management – to guarantee normal soil functions – are important elements of sustainable (agricultural) development, having special importance both in the national economy and in environment protection.
The main soil fu...nctions in the biosphere are as follows: conditionally renewable natural resource; reactor, transformer and integrator of the combined influences of other natural resources (solar radiation, atmosphere, surface and subsurface waters, biological resources), place of „sphere-interactions”; medium for biomass production, primary food-source of the biosphere; storage of heat, water and plant nutrients; natural filter and detoxication system, which may prevent the deeper geological formations and the subsurface waters from various pollutants; high capacity buffer medium, which may prevent or moderate the unfavourable consequences of various environmental stresses; significant gene-reservoir, an important element of biodiversity.
Society utilizes these functions in different ways (rate, method, efficiency) throughout history, depending on the given natural conditions and socio-economic circumstances. In many cases the character of the particular functions was not properly taken into consideration during the utilization of soil resources, and the misguided management resulted in their over-exploitation, decreasing efficiency of one or more soil functions, and – over a certain limit – serious environmental deterioration.
Soil resources are threatened by the following environmental stresses:
– soil degradation processes;
– extreme moisture regime;
– nutrient stresses (deficiency or toxicity);
– environmental pollution.
Environmental stresses caused by natural factors or human activities represent an increasing ecological threat to the biosphere, as well as a socio-economic risk for sustainable development, including rational land use and soil management.
The stresses are caused by the integrated impacts of various soil properties, which are the results of soil processes (mass and energy regimes, abiotic and biotic transport and transformation and their interactions) under the combined influences of soil forming factors. Consequently, the control of soil processes is a great challenge and the main task of soil science and soil management in sustainable development.
The efficient control of these processes necessitates the following consecutive steps:
• registration of facts and consequences (information on land and soil characteristics, land use, cropping pattern, applied agrotechnics, yields, with their spatial and temporal variability);
• evaluation of potential reasons (definition and quantification of soil processes, analysis of influencing factors and their mechanisms);
• assessment of the theoretical, real, rational and economic possibilities for the control of soil processes (including their risk-assessment and impact analysis);
• elaboration of efficient technologies for the „best” control alternatives (best management practice).
Scientifically based planning and implementation of sustainable land use and rational soil management to ensure desirable soil functions, without any undesirable environmental side-effects, require adequate soil information. In the last years such data were organized into a computer-based GIS soil database in Hungary, giving opportunities for the quantification, analysis, modelling and forecasting of the studied environmental stresses and for the efficient and scientifically based prevention, elimination or reduction of environmental stresses and their unfavourable ecological and economical consequences.
Special attention was paid to the assessment of various soil degradation processes, as: (1) soil erosion by water or wind; (2) soil acidification; (3) salinization and/or alkalization; (4) physical degradation (structure destruction, compaction); (5) extreme moisture regime: drought sensitivity and waterlogging hazard; (6) biological degradation; (7) unfavourable changes in the plant nutrient regime; (8) decrease of natural buffering capacity, (9) soil (and water) pollution.
The actions against undesirable environmental stresses and their unfavourable consequences are important elements of sustainable, efficient, economically viable, socially acceptable and environmentally sound crop production and agricultural development. These are joint tasks of the state, decision makers on various levels, the land owners, the land users and – to a certain extent – of each member of the society.

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Sensitivity of maize to herbicides in experiments in Martonvásár in 2015
Published June 2, 2015
47-52

The phytotoxic effect of herbicides applied post-emergence was investigated in a herbicide sensitivity experiment set up on parental maize genotypes in Martonvásár. A total of 48 Martonvásár inbred lines and 12 single line crosses were included in small-plot experiments set up in two replications. Ten herbicides were applied at the normal a...uthorised rate and at twice this quantity. Compounds intended for pre-emergence application were applied when maize was in the 3–4-leaf stage and post-emergence herbicides in the 7–8-leaf stage of development. The extent of phytotoxicity was scored two weeks after treatment. Some of the herbicides tested are not authorised for use in seed production fields, but it is important to know how the parental genotypes respond to all types of herbicides. Phytotoxic symptoms of varying intensity were only observed on a third of the 60 parental genotypes examined; the majority of the lines exhibited no reaction to any of the herbicides. Averaged over the 60 genotypes the level of phytotoxic damage was less than 10% for the single dose. When the double dose was applied somewhat more severe damage was induced by products containing Mesotrione + Nicosulfuron or Foramsulfuron + Isoxadifen-ethyl, but this was still below 15%. The herbicide dose had a three times stronger influence on the intensity of the symptoms than the type of herbicide. With the exception of Topramezone, there was a significant difference between the effects of the normal and double doses. The greatest dose effect differences, in decreasing order, were observed for Mesotrione + Nicosulfuron, Foramsulfuron + Isoxadifen-ethyl. Nicosulfuron and Mesotrione + Terbutylazine. The Mesotrione + Terbutylazine active ingredient combination only caused mild (<10%) symptoms on a total of 11 genotypes, while the Mesotrione + Nicosulfuron combination induced more severe phytotoxic symptoms on 26 lines. When Nicosulfuron was applied alone it caused milder symptoms on fewer genotypes than in combination with Mesotrione. Among compounds of the sulphonyl-urea type, the least severe symptoms on the fewest genotypes were recorded in the case of Prosulfuron.

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Phytotoxicity levels in a wet year in an experiment on maize sensitivity to herbicides
Published November 2, 2014
92-96

The phytotoxic effects of herbicides applied pre-, early post- and post-emergence were studied in maize in a herbicide sensitivity experiment were set up in Martonvásár and Törökszentmiklós. The herbicides were applied in normal and in double doses to 37 Martonvásár inbred lines and to six parental single crosses. The small-plot experime...nts were set up in two replications. The wet weather that followed the pre- and early post-emergence treatments promoted the appearance of phytotoxic symptoms on maize. The degree of phytotoxicity was recorded on the 14th day after post-emergence treatment and on the 14th and 28th days after the pre- and early postemergence treatments. Herbicides applied pre-emergence only caused slight symptoms on maize. Although the double dose increased the damage, it was still not more than 5% on average. The symptoms caused by herbicides applied in the early post-emergence stage were more intensive than those detected in the pre-emergence treatments. However, the damage caused by the double dose of isoxaflutol + thiencarbazone-methyl and by the split treatment with nicosulfuron remained below 10%. The symptoms became somewhat more severe at the 2nd scoring date. Among the post-emergence treatments the maize genotypes had the least tolerance of the mesotrione + nicosulfuron combination of active ingredients, where the double quantities resulted in 13–14% damage in average.

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The Role and Significance of Soil Analyses in Plant Nutrition and Environmental Protection
Published March 4, 2006
3-8

Hungary has a rich history of soil analyses and soil mapping. Our main tasks today are the preservation of soil fertility as well as balancing the goals of production and environmental protection. The main requirement of agricultural production is to adapt to ecological and economic conditions.
In a series of consultative meetings in the pas...t seven years, representatives from Central and Eastern Europe have analyzed nutrient management practices in their respective countries. According to a joint memorandum agreed upon in 2000, in the countries awaiting accession, the quantity of nutrients used per hectare is considerably smaller than the Western-European usage targeted through special subsidies. The current low nutrient usage contradicts the principles of sustainability and that of the efficient use of resources, jeopardizing soil fertility.
In Hungary, the use of inorganic fertilizers underwent a dynamic development, which manifested itself in an almost tenfold usage growth between 1960 and 1985. This growth slowed down somewhat between 1985 and 1990 and then reduced dramatically after 1990, reaching record lows at the usage levels of the 60s. The nutrient supply has had a negative balance for the last 15 years.
The increasing and then decreasing usage trends can equally be detected in the domestic yield averages of wheat and corn as well as in the nutrient supply of soils. Yields were the largest when usage levels were the highest, and decreased thereafter. Draughts have also contributed to smaller yields. The dramatic decrease in the use of inorganic fertilizers when adequate organic fertilizers are lacking endangers our soils’ fertility.
About 50% of soils in Hungary are acidic. Acidity is mostly determined by soil formation, but especially on soils with a low buffering capacity, this acidity may intensify due to inorganic fertilizers. Sustainable agriculture requires the chemical improvement of acidic soils. According to their y1 values, the majority of our acidic soils need to be improved. This chemical soil remediation is required in 15% of the acidic soils, while it’s recommended for another 20% of these soils.
Results of the analyses conducted in the framework of the soil-monitoring system set up in Hungary in 1992 show that in 95% of the analyzed samples, the toxic element content is below the allowable limit. Cultivated areas are not contaminated; toxicity above the legal level was found only in specific high-risk sampling areas: in the vicinity of industry, due to local overload. The basic principle of sustainable agriculture is to preserve soil fertility without undue strain on the environment. The intensity of the production needs to be considered according to the conditions of the site; i.e.; nutrient management needs to be site-specific. It is recommended to differentiate three types of cultivated land in terms of environmental sensitivity: areas with favorable conditions, endangered areas, and protected areas, and then to adopt nutrient management practices accordingly. To meet all the above-mentioned goals is impossible without systematic soil analysis. Tests conducted by the national monitoring system cannot replace regular field measurements.

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Timing it right: The Measurement and Prediction of Flowering
Published September 5, 2002
17-22

Although the model described here was developed from research in controlled environments, there is now considerable evidence that in can be applied to a very wide range of natural environments in several species. Multi-locational trials augmented by successional sowing and, if considered necessary, supplementary illumination in the field to inc...rease daylength, can be used to estimate the values of the model coefficients: (1) to characterize germplasm collections and so predict flowering behaviour elsewhere; (2) for interpreting and understanding crop adaptation; and (3) for genetic analysis of photoperiod sensitivity. We do not yet know whether the model has any contribution to make to the understanding of the biochemical mechanisms of photoperiod and temperature responses, but at the very least, it should provide the basis for indicating the most appropriate environmental conditions, genotypes and physiological stage of the plants most suitable for such investigations.

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Element content analyses in the Institute for Food Sciences, Quality Assurance and Microbiology
Published November 13, 2012
203-207

The role of chemical elements to ensure and promote our health is undisputed. Some of them are essential for plants, animals and human, others can cause diseases. The major source of mineral constituents is food, drinking water has a minor contribution to it, so the knowledge of elemental intake through food is crucial and needs continuous moni...toring and by this way it promotes the food quality assurance and dietetics.
With the evolution of spectroscopic methods increasingly lower concentrations could be determined, so the elemental composition of a sample could be more precisely and fully described. Due to the results the gathered knowledge up to the present is supported and new observations can be done helping us to understand such complex systems as biological organisms are.
The quality of a food is determined by the full process of its production, consequently it starts with agricultural production so elemental-analysis usually cover the whole soil – plant – (animal) – food chain, by this way the „Fork-to-Farm” precept is true in elemental analysis field also.
The history of elemental analysis in the University of Debrecen, Centre for Agricultural and Applied Economic Sciences, Faculty of Agricultural and Food Sciences and Environmental Management, Institute of Food Processing, Quality Assurance and Microbiology goes back to 1980s when the so called Regional Measurement Central gave the background for research. The continuous deployment resulted in an obtain of an inductively coupled plasma atomic emission spectrometer (ICP-AES) in 1988, which extended the scope of examinations due to its excellent performance characteristics
compared to flame atom absorption (FAAS) and flame emission spectrometers (FES). The instrumental park retain up to date correlate to the developing analytical techniques due to acquiring a newer ICPAES in 1998 and an inductively coupled plasma mass spectrometer in 2004 – which sensitivity is three order of magnitude better compared to ICP-AES. The Institute supports the work with its own ICP-AES and ICP-MS since 2011. 

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The Examination of Some Determining Elements of Efficient Practical Sweet Corn Growing
Published November 2, 2009
81-85

We did the detailed agronomy examination and assessment of sweet corn cropping technology by analysing the data of TONAVAR Ltd. The Ltd. developed a special sowing construction which is based on band application of main sowing and double growing. In main sowing they use super sweet hybrids, and in double growing they use normal sweet varieties.... In double growing sugar peas and the sweet corn can be cultivated together successfully. In every two years appearing sugar peas has a good effect on the sweet corn growing in monoculture. At the same time
the long-term successfulness of this questionable onto the illnesses of the peas because of the considerable sensitivity.
According to our examinations in main sowing the optimal period is between May 1. and 30., and in double growing the optimal period of sowing is between June 1. and 20. The optimal plant density is different too for the two sowing time. For super sweet hybrids the optimal plant number is 60-63 thousand/ha and for the normal sweet that is 65 thousand/ha.
Our examinations show that soil pest (defence with soil sterilisation in sowing time), Diabrotica virgifera, Helivoverpa armigera, Ostrinia nubialis are the greatest danger for the sweet corn quantity and quality.
The use of herbicides is the most efficient in the postemergens in main sowing and preemergens in second crop.
Our examination shows that the efficient sweet corn growing cannot be imagined without irrigation. The most efficient irrigation is in main sowing in the critical fenophase of crop time. In double growing the initial irrigation, and the crop irrigation are the most efficient. Based on the production data verifiable that beside the application of the discribed growing technology in the 2005-2007 years the average yield was 20,9t/ha of main sowing, and 17,8t/ha of second crop on chernozem soil in the Hajdúság. 

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Testing of paraffin oil efficiency against grape powdery mildew in Eger wine region
Published February 18, 2016
73-80

The aim of the present study was to examine the efficiency of paraffin oil against powdery mildew in Eger wine region. The experiment has been carried out in 2013 and 2014 with Chardonnay and Kékfrankos grape varieties, which have different resistance against powdery mildew. The effectiveness of the oil was examined on leaves and clusters (fre...quency and intensity). This oil was effective against Erysiphe necator infection on field trials in Chile and Brazil. The spread of downy mildew (Plasmopara viticola) was also inhibited by this material in some experiments conducted in Spain and France.

The differences between oil treatments represented the sensitivity of the grape varieties in accordance with the applied dosages. The oil was effective against powdery mildew with different extent as a result of the so called ”vintage effect”. In 2013, the treatment of the highest dosage (D3) didn’t differed significantly in frequency and intensity of infection from the regular treatment (clusters of Kékfrankos, leaves of Chardonnay). In 2014, the oil was not so effective against powdery mildew compared to 2013. No remarkable differences were detected between the treatments due to the strong pressure of powdery mildew. Furthermore, no any effect of the lowest dosage (D1) was detected in the case of the sensitive clusters of Chardonnay and leaves of Kékfrankos in both experimental years.

In summary, the oil treatment has an effect against powdery mildew, however this efficiency largely depends on the vintage characteristics and the pressure of powdery mildew. Further investigations are neccessary, for example field trials with combinations of other sprays. The oil can be useable as fungicide with proper care in eco-friendly integrated and bio (ecological) viticulture.

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Investigation of the Resistance Against the Fusarium solani at Different Pea Varieties and Combinations of Breeding
Published May 11, 2003
157-160

The Fusarium species are soil and polyphage parasits, and the rate of damage, caused by them, highly depend on interactions between climatic and edaphic factors and also on sensitivity of cultivars. Even though about 70-80 percent of the widely grown green peas cultivars is resistant to Fusarium oxysporum f. sp. pisi 1. race, the rate of Fusari...um infections and severity of symptoms increased in the latest years. It is supposed that another Fusarium sp. the Fusarium solani has been spreading. The most exact way to study the cultivars in a provoking garden established in natural environment, where the pathogen is artificially enriched to a level, at which the cultivars can be distinguished according to their susceptibility. In the provoking garden the reaction against to Fusarium of our breeding lines and our registered cultivars and cultivars existed on the National List (including cultivars with well-known susceptibility as standards) are examined year by year. In our experiments we could found two green peas cultivars to be resistant to Fusarium solani (Early sweet (13,36%) and Lora (16,9%)) The breeding lines Margit and 8607/75-3-2 proved to be the most susceptible to Fusarium solani (94,4% and 73,1% infected plants, respectively).

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Determination of the validation parameters of inductively coupled plasma mass spectrometer (iCP-mS): response curve linearity in the case of arsenic and selenium
Published July 31, 2012
67-71

In the field of elemental analysis inductively coupled plasma mass spectrometers (ICP-MS) have the best sensitivity that means the lowest limit of detection, subsequently their applicability for the detection of essential and toxic elements in foods and foodstuffs is prominent. For the most elements could be measured the detection limit is betw...een μg kg-1 (ppb) and ng kg-1 (ppt) e.g. for arsenic and selenium.

Considering an analytical task (sample type, analytes and their concentration, pretreatment procedure etc.) the applicability of an analytical method is determined by its performance characteristics. The purpose of validation is to ensure that the method would be used fulfills the requirements of the given task. In this article we describes one of the performance characteristics, the linearity, and the whole validation procedure aims measurement of arsenic and selenium in foodstuffs by inductively coupled plasma mass spectrometer (Thermo XSeries I.); but because of the limited number of pages the results are demonstrated only for arsenic.

The linearity of calibration was evaluated in three concentration ranges (0.1–1 μg l-1; 1–10 μg l-1; 10–50 μg l-1), with nine line-fit possibilities (without weighting, weighting with absolute or relative deviation; with or without forcing the curve through blank or origin) and different methods (graphical examination, correlation coefficient, analysis of variance).

The best method to ensure the linearity of correspondence between signal and concentration was the ANOVA test. In view of calibrations it was found that the range of 10–50 μg l-1 could be regarded as linear with four line-fit possibilities, and was non-linear between 0.1–1 μg l-1 and 1–10 μg l-1.

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Research on the allelopathic effect among the species Tanacetum vulgare and some agricultural crops
Published November 10, 2010
105-109

The research presents the results of the allelophatic effect upon the germination and growth of plants, immediately after springing, viewed as the interaction between the species of Tanacetum vulgare sin Chrysanthemum vulgare and three other crops: wheat (Triticum aestivum L.), barley (Hordeum vulgare L.), rape (Brassica napus ssp. oleifera L.).... The experiments that were performed consisted in applying treatments with aqueous extracts obtained from the roots, leaves, stems and flowers harvested from T. vulgare plants upon the seeds of the three agricultural crops mentioned before. In all aqueous extracts, the results indicate the presence of some chemical compounds that have inhibiting allelophatic effect. The plants upon which tests were made showed great sensitivity, the results on their germination and growth being significantly negative and highly significantly negative.
The conclusions of this research sustain the idea of setting new research objectives in order to discover the chemical compounds from T. vulgare extracts that have such a stong effect and the possibilities they offer.

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Effect of cropping technologies on the yield of dry bean variety ’Diana’
Published February 18, 2016
37-41

An experiment on three dry bean varieties (Start, Hópehely, Diana), using different sowing-times, fertilizers and plant densities was performed on sandy soil in the University of Debrecen, Centre for Agricultural Sciences, Research Institute of Nyíregyháza in 2015. The aim of the experiment was to study which treatment gives the highest yiel...d, and whether the different treatments result in significant differences in the yields. In this paper the dry bean yield at ‘Diana’ variety is analyzed.

The treatments were done with three fertilizer doses and three plant densities at different sowing-times (April 24; May 8; May 18). As a result of the high temperature and the drought during the growth season, the yields we harvested were in low, which shows the ecological sensitivity of the plant we examined.

We concluded that the poorest yield was harvested at the third sowing-time. There was no significant difference in the yields at the first and second sowing- time. Examining all the three fertilizer treatments we applied at the experiment, we achieved the highest yields in the control plots. It might be due to the weak efficiency of nitrogen fertilizer under the extremely dry conditions. The highest yield was harvested at the control treatments during the second sowing-time. Regarding the effect of the plant densities, the highest crop yield was achieved at the treatment using 400 000 germs ha-1, followed by 300 000 germs ha-1 and 200 000 germs ha-1.

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The Effect of Zanthium Extracts on Germination in Relation to Interior and Exterior Factors
Published May 4, 2004
65-69

In Hungary, the cocklebur species significantly endanger row crops (i.e. corn, sunflower, sugar beet). Their fast spreading is caused by many reasons: long-lasting emergence, reduced sensitivity to many kinds of herbicides, vigorous competitional ability, allelopathy, fast initial growth and changes in climate. The means of allelopathy is used ...by many species of plants in the competition with one another, as well as by the cockleburs. But the efficiency of this is influenced by many factors. Species with allelopathical effect could show different behaviour under different conditions: they can produce compounds with retarding and stimulating effects in different quantities or compositions. The actual condition of the acceptor plant and the mediator agent (i.e. soil) influence the final effect.
In this experiment influence of phenology and rainfall was studied on allelopathy of cockleburs in May, July and September. A stronger inhibition was observed on growth of cress before rain in July than in May, but this retarding effect disappeared after rainfall. However, the samples collected in September have significant inhibitory effect after rain. Inhibition of sugarbeet’s germination was stronger in May than in July, and the difference increased after rain.

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The effect of water-stress on the mineral nutrition of fruit plantations
Published October 5, 2010
187-192

Besides agro-techniques the climatic conditions play an important role in agricultural production. Weather extremes are
significant hazards to many horticultural regions all over the word. It has a profound influence on the growth, development and yields of a
crop, incidence of pests and diseases, water needs and fertilizer requirements i...n terms of differences in nutrient mobilization due to water
stresses. Nowadays, the weather extremes cause 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 followed from climatic anomalies and response it. In this study
we focus on water supply problems (water-stress).
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.
· 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.
· The role of foliar spraying, mulching and fertigation/irrigation is increasing continuously.
· 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. Moreover, mulching is regarded as an excellent water saving
method.

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Sensitivity study on Virginia fanpetals (Sida hermaphrodita (L.) RUSBY) cv PETEMI to different herbicide agents
Published November 10, 2010
89-92

The cultivation of Virginia fanpetals (Sida hermaphrodita (L.) Rusby) is a relatively new phenomenon in Europe. On the basis of the biology of the plant and the practical work implemented, it has been stated that the traditional field practice does not provide the appropriate conditions of biomass production for energetic purpose. The developme...nt of the proper weed control is inevitable for the healthy stand, as in the early phenophases the plant is growing slowly and it is exposed to weeds. 
Our objective was to test some herbicide agents as no previous relevant data had been published.

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Establishing biotic stress tolerance of maize (Zea mays L.) by measuring hydroxamic acid contents
Published June 30, 2018
107-112

 

Cyclic 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, wher...e 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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Effect of M9, MM106 and Seedling Rootstocks on Sunburn-Sensitivity of 33 Apple Cultivars, and Sunburn Effects on Fruit Quality
Published December 6, 2005
236-247

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

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The role of non-optimum Fe-Zn ratio in the development of latent zinc shortage in cucumber (Cucumis sativus L.)
Published March 20, 2013
7-11

...5); font-variant-ligatures: normal; font-variant-caps: normal; -webkit-text-stroke-width: 0px; text-decoration-style: initial; text-decoration-color: initial;">The general micronutrient deficiency of the soils influences the quality of food production which causes human health problems in several countries as well. The non optimal Fe-Zn ratio can cause latent zinc deficiency – which the plants response in the function of their sensitivity –what has no visual symptoms or the plant shows deficiency symptoms in case of appropriate zinc supply. This phenomenon can cause significant decrease in the crop yield.

The aim of this study was to prove the role of non optimal Fe-Zn ratio in the evalution of latent zinc deficiency.

The non optimal Fe-Zn ratio caused decrease in the number of the leaves, the number and length of the internodes, the relative chlorophyll contents and in the dry matter production. According to the results the non optimal Fe-Zn ratio caused difficulties in the metabolism, which decreased the examined plant physiological parameters in the most cases. It can be concluded if there are higher iron contents in the tissues than zinc it can result latent zinc deficiency.

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The effect of irrigation on the yield and quality of maize (Zea mays L.) hybrids
Published May 20, 2020
143-147

In this study, the effect of water supply on the quality and productivity of different maize hybrids was observed.

Maize production is influenced by many agro-technical factors such as nutrient supply, plant density, environmental factors, water supply and temperature. Good soil quality and adequate technology significantly... reduce the unfavourable effect of crop year. The impact of fertilization, crop rotation, irrigation and plant density on maize yield was greatly affected by crop year and crop rotation. The main constituent (69–75% dry matter concentration) of maize seed is starch, however, its increase can be achieved only to a limited extent, as increasing the starch content will reduce other parameters, especially protein content. Significant nutrient content improvements can be achieved by appropriate hybrid-site connection and the use of adequate technology. Protein content reduction with optimal water supply can be positively influenced by the appropriate nutrient supply for the hybrid.

The experiments were carried out at the Látókép Experimental Site of Crop Production on calcareous chernozem soil. The weather of the examined year, which was partly favorable for maize and partly unfavourable in other respects, was also reflected in the development of maize and yields achieved.

In 2019, we were examining the hybrids of Kamaria (FAO 370), P 9903 (FAO 390), DKC 4351 (FAO 370) and KWS Kamparis (FAO 350–400). Due to the dry soil condition, sowing was delayed, however, the hybrids emerged ideally because rain arrived soon after sowing, which facilitated initial development. Young plants evolved rapidly and dynamically in the case of all hybrids. In terms of heat-demanding bread, the month of May was unfavourable to temperatures below the annual average, but the higher amount rainfall helped the development. However, due to the drier period in early July, 25–25 mm of irrigation water was applied to half of the experimental areas on July 1 and 15.

The aim of our research was to determine the best population density for hybrids under favourable soil conditions (calcareous chernozem soil). In both irrigated and dry conditions, a crop density of 75,000 crops were the most favourable for the Kamaria hybrid. The P9903 hybrid in the case of a crop density of 85 crops proved to be ideal and the DKC4351 had an optimal population density of 95,000.

However, it should be taken into consideration that, in the case of soils with poor water management, the drought sensitivity of the crop stand may increase at a population density of 95,000.

As a result of irrigation, yield increased and the difference between the examined plant numbers decreased. The yield growth was relatively moderate (341 kg ha-1 – 1053 kg ha-1), which makes the economicalness of irrigation doubtful in the given year.

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Studies on the Fusarium stalk rot infection of the maize genotypes using the Findex percentage and a computerised image analysis program
Published October 30, 2011
45-51

In a continental climate, the pathogens causing the most serious problems are species belonging to the Fusarium genus. When the pathogen attacks the stalk, the plant dies earlier, reducing grain filling and resulting in small, light ears. In addition, the stalks break or lodge, resulting in further yield losses from ears that cannot be harveste...d. During the three years of the experiment, 14 inbred lines were examined. The genotypes were sown in a two-factor split-plot design with four replications, with the genotypes in the main plots and four treatments in the subplots: two Fusarium graminearum isolates (1. FG36, 2. FGH4), 3. sterile kernels, 4. untreated control. The results experiments showed significant differences between the genotypes for resistance to fusarium stalk rot. Among the inbred lines the best resistance to fusarium stalk rot was exhibited by P06 and P07, both of which were related to ISSS. The precision and sensitivity of disease evaluations carried out visually and using image analysis software were compared in the experiment, and with two exceptions the CV values were lower for the image analysis. As the CV for measurements can be considered as a relative error, it can be stated that image analysis is the more precise of the two methods, so this technique gives a more accurate picture of the extent of stalk rot. The extent of stalk rot developing in response to natural infection is extremely environment-dependent, so the use of artificial inoculation is recommended for selection trials. 

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Allelopathic effects of water extracts of pieces of wooly cupgrass (Eriochloa villosa) on the seedlings of field crops
Published May 16, 2017
167-170

In Hungary, the woolly cupgrass (Eriochloa villosa [Thunb.] Kunth) endanger row crops (i.e. corn, sunflower). Its fast spreading based on some reason viz. long-lasting emergence, reduced sensitivity to many kinds of herbicides, vigorous competitional ability and fast initial growth. Allelopathy, ability of many plant species to produce one or m...ore biochemicals wgich is used tocompete with each others. In this experiment we examined, whether the woolly cupgrass possesses allelopathy, and if so, how influences on the development of cultured crops like maize, sunflower and lettuce.

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