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  • The impact of climatic factors on the relative chlorophyll content and yield of a maize hybrid in a long-term experiment
    71-77
    Views:
    211

    The impact of the climatic factors of crop year on the relative chlorophyll content of maize was examined for three years. The examinations were carried out on the Látókép Experiment Site of the University of Debrecen on calcareous chernozem soil in a small-plot, non-irrigated long-term field experiment with strip plot design. In addition to a non-fertilised (control) treatment, nitrogen (N) fertiliser doses were applied as base and top dressing. The 60 and 120 kg N ha-1 base dressing doses were followed by two top dressing doses at the V6 and V12 phenophases.

    Averaged over the different fertiliser treatments, SPAD readings increased in all three years as the growing season progressed. The highes SPAD value increase was observed in the average crop year (2017) at the V12 phenophase (11.8), which further increased at the R1 phenophas, by 3,7. No significant Spad value difference was observed between the average (2017) and the dry year (2018) at the V6 growth phase. However, in the wet crop year (2016), the V690 treatment provided the statistically highest relative chlorophyll content (46.8). At the V12 phenophase, the base dressing dose of 120 kg N ha-1+30 kg N ha-1 (V6150) showed to be successful in two years (2016 and 2018), while in 2017, the base dressing dose of A60 was successful. The impact of crop year on relative chlorophyll content can be clearly shown at the R1 growth stage. In all three years, the significantly highest relative chlorophyll content could be achieved at different nutrient levels: A60 in 2016, V6150 in 2017 and V690.

    In a wet year (2016), higher yield could be achieved as a result of the 60 kg N ha-1 base dressing and 30 kg N ha-1 at the V6 growth stage (V690) as top dressing in comparison with 2017 and 2018, when higher fertiliser dose (120 kg N ha-1 base dressing and 30 kg N ha-1top dressing at the V6 growth stage) was needed to achieve a significant yield surplus.

    Altogether, averaged over the different treatments, the highest yield (12.48 t ha-1) was observed in the wet year, when the relative chlorophyll content was also the highest (50.6).

  • Yield and sward composition responses of a native grassland to compost application
    35-38
    Views:
    182

    A major part of the animal products are based on the grasslands, due to the fact that the grassland ecosystems can be found all over the globe. In places where economical and successful crop production cannot be realized, the grassland based animal husbandry can be an efficient way of food production. In addition these ecosystems have an important role in carbon sequestration, and with their rich flora – and the fauna connected to it – in conservation of biodiversity. The protection of nature, and the sustainable agriculture is getting more and more attention in the European Union, but looking at the consumers’ needs, the production of healthy food cannot be neglected either. Because of these facts, the effects of two specific composts - which are officially authorized in organic farming, in Agri-environment Schemes and Natura 2000 programs – on grass yields and sward compositions were investigated in a field trial. The investigation took place in Hungary, on a natural grassland based on solonetz soil. The first type of compost was a natural one (N) without any additional material and the other one was enriched in phosphorus (E). Both was produced by the research institute, made of sheep manure. Three rates of compost (10 t ha-1, 20 t ha-1,30 t ha-1) were tested on 3 m×10 m experimental plots. Every treatments had four replications and both type of compost had four-four control plots too, this way 32 experimental plots were included in the investigations. The yield of the pasture was harvested two-times (in May and in September) and before cutting the plots measurements on botanical compositions were made. Samples for laboratory analysis were also taken. Dry matter yield and crude protein content was measured in laboratory and with the received data the yield per unit area was calculated. Based on the research results we can say that the application of compost in any dose inflicts higher dry material and crude protein yield. The changes were partly due to some positive changes in sward composition, because of the better nutrient conditions. The research results indicate, that use of organic compost can be an efficient way to increase grass yields in a sustainable way.

  • Mitigation of environment impact of mycotoxins produced by Fusarium species
    159-164
    Views:
    166

    The Fusarium fungi hazards the grain quality of cereals, therefore significantly affects their utilization as animal feed or consumable product. The Fusarium can decrease the quality of wheat in different ways: decreases the germination capability, causes visible discoloration, mould may appear, reduces the dry material and nutrient content of the grain, causes mycotoxin infection – as a result given by its by-product. Micotoxins produced by Fusarium genus, as the trichotecenes (T-2, HT-2, deoxynivalenol, nivalenol, diacetoxyscirpenol, Fusarenone-X) and the zearalenone (F-2) are the most common in Hungary. Occurrence of fumonisins first discovered in 1988 are must be identified carefully. About 20–30% of the overall worldwide production of cereals is infected with Fusarium and its toxins, which situation is similar in Hungary. This infection causes serious yield-losses in cereal production. In the case of cereal products, which non-utilizable as forage seems, an optimal solution is utilizing as biogas raw material, but it is also important to examine the effect of the infected cereal on the anaerobe digestion process.

  • The effect of compost application on physical properties of sandy soil
    67-70
    Views:
    165

    The sewage sludge compost is suitable to improve the colloid-poor sandy soils, which are common characteristics of poor water- and nutrientholding capacity. The general characteristics of sandy soils are the light mechanical composition, the low content of humus and mineral colloids, large pore size and a bad aggregate stability. They have a poor nutrient supply capacity, due to its high porosity the organic matter is degraded very quickly to mineral colloids (Stefanovits et al., 1999).

    By the compost application the soil is enriched mineral and organic colloids, thereby improving the soil structure. The effect of addition of compost to soil the water- and nutrient-holding capacity and porosity could be increased and the bulk density could be decreased (Martens and Frankenberger, 1992).

    The aim of our experiment is to carry out physical measurements to determine the effects of compost treatment. In this study the results of the first year are presented.

  • Nutritional disorders of arable crop growth in eastern Croatia
    273-290
    Views:
    140

    Nutritional imbalances accompanied with growth retardation of crops at early growth stage were found since the last 40 years on certain arable lands in eastern Croatia. In this regard, phosphorus (P) deficiencies in maize and wheat were found mainly on acid soils of the western part of the region, potassium (K) deficiencies in maize, soybean on the hydromorphic neutral to alkaline calcaric drained gleysols of Sava valley lowland, while zinc (Zn) deficiencies were observed mainly in seed-maize and soybean on neutral calcaric eutric cambisols of the eastern part of the region. Cold and moist spring is factor promoting P deficiency symptoms. As oasis of normal crops existed on same arable land, comparison of plant and soil composition was possible from typical sites. P nutrition disorders were in connection with the lower P and the higher aluminum (Al) and iron (Fe) concentrations in the top of plants and the lower soil pH values. K-deficiency as result of strong K fixation and imbalances with high levels of magnesium (Mg) were the main responsible factors of low maize and soybean yields on some drained gleysols. Chlorosis incidences typical for Zn deficiency in maize and soybean were in close connection with the higher soil pH, the lower quantities of mobile Zn, here and there the higher mobile P in soil, the lower concentrations of Zn and the higher levels of Al and Fe in plants. Overcoming the above mentioned disorders and normalization of yields were achieved using ameliorative fertilization either by K or P fertilizers and in case of Zn by foliar spraying of crops with 0.75% ZnSO4 solution. Also, alleviations are possible by selection of more tolerant genotypes of field crops to specific types of nutritional disorders. From this aspect, some practical solutions were recommended for maize with reference to K nutritional problems.

  • The Effects of Corn Cobs in Feed
    51-54
    Views:
    105

    This study is part of a larger research work that aims to establish the usefulness of corn cobs, a low cost dietary resource, in the growth of ruminants. Corn cobs are found in large amounts in our country (8.2 mil. tons/year). Increasing the quantity of corn cobs to 50% of the diet in lambs resulted in a decrease by 14.57% in the concentrate intake that is needed to obtain one-kg weight increase. In addition, the diet costs were reduced by 16.33% (Mierliţă, 1999). Increasing the quantity of corn cobs to 20-50% of the diet also resulted in multiplication of bacteria from genus Ruminococcus, that are known to represent about 70-80% of the bacteria population in the rumen. In addition, an increased multiplication rate of large protozoas (i.e. Epidinium, Isotrichia, Diplodinium etc) was observed. This explains the high conversion rate of piruvic acid, a carbohydrate fermentation product, into acetic acid, whereas conversion of piruvic acid into propionic acid decreases. In addition, feed intake and the quantity of digested and absorbed fibers increased by 8.46% and 35.09%, respectively. Thus, a reduction in dietary concentrates needed as nutrient supplies was achieved.

  • Relationships between nutrientsupply, genotype and some physiological properties of winter wheat
    141-145
    Views:
    146

    The chlorophyll content (SPAD), leaf area index (LAI) and leaf area duration (LAD) of three winter wheat varieties have been investigated on a chernozem soil. Three winter wheat varieties (GK Öthalom, Pannonikus and Genius) in three different nutrient-supply levels have been involved in our experiment in the crop-year of 2010/2011. The investigated physiological properties have been set against to the yield results. Upon the results of this comparison it has been stated that there is a close relationship between the investigated physiological properties and yield averages. The SPAD-values showed a growing tendency parallel to the growth of the nutrient-supply levels. The varieties have the highest SPAD-values at the nutri ent-level of N120+PK. Compared to the yield averages we have stated that varieties that have higher SPAD-values have realized higher yields as well. Higher nutrient dosages have increased in the leaf area. In case of all the three varieties the highest LAI-values were measured at the flowering stage (23. 05.) in the treatment whit N120+PK. Varieties with higher leaf area have produced higher yields as well. Parallel to the increasing nutrient-supply levels the value of leaf area duration increased as well. We measured the highest LAD-values in the treatment of N120+PK nutrient-level. By the LAD-values it can be stated that more durable and larger leaf area has been produced in the flowering and ripening phenophases, due to the higher nutrient-dosages. Analysing the relationships between the results it can be stated that there is a strong positive relationship between fertilizer treatments and SPAD-, LAI- and LAD-values. The genotype showed a strong positive correlation to SPAD-values. Yield averages showed strong positive correlation to SPAD-, LAI- and LAD-values as well.

  • Effect of arsenic treatments on physiological parameters of sunflower and maize plants
    81-84
    Views:
    174

    The environment is contaminated with heavy metals and other toxic compounds. One of the most important toxic element is the arsenic (As).

    The objective of our study was to investigate the effect of As on fresh and dry weight of sunflower and maize in the early growth phases.

    Seedlings were grown in climate room on nutrient solution which were treated with 3, 10 and 30 mg kg-1 arsenic. The plants were treated separately with As(III) and As(V). After 14 day, changes in fresh and dry weight of maize shoots and roots were recorded. In the case of sunflower these parameters were measured after 21 day.

    The applied As(III) and As(V) decreased the fresh and dry mass of the shoots and roots of seedlings, especially at concentration 30 mg kg-1. We can draw the conclusion that the treatments of the maize and sunflower roots with arsenic had negative effects on the biomass accumulation. We found that the sunflower plants are more sensitive to arsenic toxicity than maize plants, and all data demonstrate that the As(III) is more toxic to these plants than the As(V).

  • Effect of different N doses on maize yield and quality
    97-101
    Views:
    164

     The effect of N doses on the yield and nutritional values of the Sushi (FAO 340) maize hybrid were analysed in three years (2018, 2019, and 2020). The analyses were performed at the Látókép Experimental Station of the University of Debrecen on calcareous chernozem soil, in a striped, small-plot, non-irrigated long-term field experiment. In the experiment, in addition to the non-fertilized treatment (A0), the N-fertilizer doses were applied as basic fertilizer and top dressing. The 60 and 120 kg N ha-1 dose (A60, A120) applied as spring basic fertilizer were followed by two phases of top-dressing in V6 (V690, V6120) and V12 (V12150, V12180) phenophases; the amounts were +30 and +30 kg N ha-1.

    Maize yields were affected to varying degrees by crop year. The highest yields in 2018 and 2020 were recorded in the same V6150 treatment, while in 2019 the highest yield was obtained in the A120 treatment.

    Increasing the N doses resulted in an increase in the protein content of the maize kernel. Depending on the fertilizer treatments and the crop year effect, the protein content of maize kernels varied between 6.2–10.2 g x 100 g-1. In all three years, the protein content was the lowest in the control treatment (A0) and the highest in the V6150 treatment.

    The starch content ranged from 70.7 to 77.9 g x 100 g-1 in the average of the three years. In 2020, it was significantly higher in all nutrient treatments than in the other examined two years. The highest starch content - except for 2020 (A120, 77.9 g x 100 g-1) - was recorded in the A0 treatment (74.2, 72.3 g x 100 g-1).

    The oil content of maize kernels varied between the values of 3.8 and 5.2 g x 100 g-1 in the average of three years. In terms of oil content, the results for 2018 and 2019 can be considered the same, while in 2020 it was significantly lower. Fertilizer treatments did not significantly affect the oil content of maize in any of the years.

    The fertilizer dose applied in the V12 phenological phase was not effective in terms of yield and nutritional content (protein, starch and oil content).

  • Studies of the effects of N fertilizers and Microbion UNC biofertilizer on microelement content of horseradish (Armoracia macrocarpa)
    41-45
    Views:
    117

    A field experiment on calcareous chernozem soil was performed to study the effects of different N and bacterial fertilizers on the nutrient content of horseradish (Armoracia macrocarpa). In the experiment the trials were arranged in a randomized block design with three replications, applying three levels of NH4NO3 and different N fertilizers, namely ammonium-nitrate, urea and calcium-nitrate, with or without application of Microbion UNC biofertilizer.
    In the present paper the changes and distribution of manganese, zinc and copper contents of the horseradish plant are summarized by the
    effect of different treatments.
    The Mn content of leaves were higher in all cases than those of roots, but Zn mainly accumulated in the roots. The distribution of copper within the horseradish plant was more equalized than that of Zn and Mn. Different N fertilizers and increasing doses of ammonium-nitrate had effects mainly on the microelement contents of leaves. The highest Mn contents of plant were measured in treatments of Ca(NO3)2 and Ca(NO3)2+Microbion. The lowest ammonium nitrate dose (N1) decreased the Mn content of leaves compared to control, but further doses
    (N2, N3) did not alter these values any longer. Microbion UNC biofertilizer did not have any effect on the Mn content of roots, but we measured higher Mn in leaves in some combined treatments. Ca(NO3)2 increased the zinc content in leaves and roots in a noticable manner. With the increasing of NH4NO3 doses, the Zn content of leaves and roots augmented significantly. Neither N fertilizers (or the increasing doses of NH4NO3) nor the biofertilizer application influenced the Cu content of horseradish plant. 
    N fertilizers had higher effects on the microelement content of horseradish, the biofertilizer’s effect was smaller and was not the same in every treatment.

  • The effect of lead and copper heavy metal salts on soil microorganisms under laboratory circumstances
    55-59
    Views:
    151

    he population dynamics of calcareous chernozem soils polluted with different concentrations of lead and copper heavy metal saline solutions was examined.

    The experiment was carried out in the soil biological laboratory of the Institute of Agricultiral Chemistry and Soil Science at DE AGTC MÉK in 2012. For the determination of the concentration of the undiluted stock solutions we multiplied the smallest toxic concentration values of the MSZ 08-1721/1-86 Hungarian standard by forty. The intermediary concentrations of the treatments were produced with adequate dilution of the stock solutions until a dilution level equal to the values of the standard. The statistical evaluation of the data was performed with ANOVA (Analysis of Variance) including the determination of the standard deviation and significant difference. Investigating the effects of the different treatments on the soil microbes we established that both heavy metal saline solutions had a negative effect on the population dynamics of bacteria and microscopic fungi living in the soils. The negative effect of copper – as a potential toxic micro nutrient – turned out to be less strong than the negative effect of the toxic lead. According to our results the correction of the treatment levels is recommended in order to further tolerance examinations and the determination of the tolerance levels.

  • Using research findings in precision maize production
    227-231
    Views:
    215

    The effect of crop production factors on maize yield are examined on chernozem soil in a more than 30 year old long-term experiment on the Látókép Experiment Site of the Centre for Agricultural and Applied Economic Sciences of the University of Debrecen. The aim of research is to evaluate the effect of fertilisation, cultivation, plant number, genorype and irrigation. The analysis of the data in the database of the examined period makes it possible to evaluate the effect of maize yield, as well as that of the crop production factors and the crop year, while the correlations and interactions between these factors were also examined. During the examination of the cultivation treatments, it was concluded that the highest yield was obtained as a result of autumn ploughing, but its effect largely differs in the irrigated and the nonirrigated treatments. Based on our examinations, strip cultivation should be applied periodically (e.g. strip – strip – ploughing – loosening) in areas with favourable soil conditions free from compacted layers. 
    In years with smaller, average precipitation supply or when the precipitation was higher than average, higher plant numbers were more favourable. Under drier conditions, but especially in several consecutively dry years, a lower plant number can be recommended which is not higher than 60 thousand per hectare. In the case of favourable water supply, 70-80 thousand plants per hectare can be  used. The yield increasing effect of fertilisation was significant in the case of both non-irrigated and irrigated conditions, but it was much more moderate in the non-irrigated treatment. The extent of weed coverage was significantly affected by the previous crop. In the case of a favourable previous crop (wheat), the weed coverage was significantly lower than after an unfavourable previous crop (maize). In the case of the same previous crop (maize), the extent of weed coverage was mostly determined by the crop year and the extent of precipitation supply. Irrigation is not enough in itself, because if it was not accompanied by intensive nutrient management, yields started to decline.
    The results of researhc, development and innovation contributed to the technological method which makes it possible to apply locally adjusted sowing seed, fertiliser and pesticide in a differentiated way, as well as to change the method of operations within the given plot.

  • Comparative study of special honey products and herbhoneys
    117-120
    Views:
    356
    Honey has a positive effect on human body due to its high content of biologically active substances (e.g. monosaccharides, vitamins, enzymes, amino acids, polyphenolic compounds). The properties of honey depend on its botanical origin due to the bioactive plant components, mainly secondary metabolites that are included in honey made by bees from nectar. Herbally infused honeys are delicious products that combine the therapeutic action of herbs and honey. Additionally, herbs can provide nutrient fortified syrup for honey bees and protect them against diseases and other ecological threats.
    The aim of this study was to define the physicochemical properties of multifloral honey, herb enriched natural honey and herbhoney samples. We measured the moisture content, pH value, electrical conductivity and proline content. Although great diversity was observed in the basic properties of the examined products. In our study, we found that the electrical conductivity shows the significant differ between the groups. All the samples, including the herbhoneys passes the quality standards of honeys.
  • Correlation analysis of relative chlorophyll content and yield of maize hybrids of different genotypes
    211-214
    Views:
    128

    In 2021, correlation between relative chlorophyll content and yield in three maize hybrids of different genotypes was examined. The data were collected at the Látókép Experimental Station of the University of Debrecen located on the Hajdúság loess ridge in Hungary. The soil of the small plot field strip plot trial, which was set up in 2011, was calcareous chernozem. Apart from the control treatment (without fertilisation), N fertiliser is applied in the form of base and top dressing. The base fertiliser containing 60 and 120 kg ha-1 N of nutrient applied in spring was followed by top dressing containing +30–30 kg ha-1 N in V6 and V12 phenophases. SPAD values measured at different phenological stages of the growing season increased by an average of about 28% up to 10 leaf stage for all three hybrids. In the pre-silking period (Vn), the relative chlorophyll content decreased by 8% on average. After an average increase of 14% in the tasselling and silking period, SPAD decreased by an average of about 29% at full maturity (R6).

    For the different fertiliser treatments, higher N doses resulted in higher yields. In the basal fertiliser treatment, the A 60 N dose resulted in an average 34% increase in yield, and the A 120 N dose resulted in an average 94% increase in yield compared to the control. The 60 kg ha-1 N basal fertiliser (A60) increased in the V6 phenophase with an additional 30 kg ha-1 N resulted in an average yield increase of 26%. When 120 kg ha-1 N of basal fertiliser (A120) was increased by an additional 30 kg ha-1 N in the V6 phenophase, only the Merida hybrid showed a significant yield increase (7%). No further yield increase was observed when V690 and V6150 treatments were increased by an additional 30 kg ha-1 N in the V12 phenophase. The yield of the Armagnac hybrid decreased by almost 20%, the yield of Fornad by 3% and the yield of Merida by 1%.

  • Az NPK-trágyázás hatása a kukorica tápelemfelvételének dinamikájára, öntözött és nem öntözött viszonyok között
    23-27
    Views:
    168

    The effect of NPK-fertilization on the dynamics of nutrient uptake of maize (Zea mays L., cv. Clarica) was examined on chernozem soil under irrigated and non-irrigated conditions in a field experiment.
    The following results were made:
    • the element concentrations in the plant decreased over time,
    • there is no difference between the dynamics of nutrients on irrigated and non-irrigated sites because rainfall was satisfactory for plants in vegetation period,
    • the N doses not only significantly increase the nitrogen content in maize, but also have a noticable effect on Ca and Mg concentrations,
    • because of the acidifying effect of N-fertilizers, increasing the amount of N-fertilizer increased the Mn, Zn, Cu content of the plants,
    • the P doses have a significant effect on the maize P and N content and the Zn concentration of the plant via P-Zn antagonism in the soil,
    • as the high K doses treatments alter the ion ratios in the soil, the Ca, Mg content of the plant decreased.

  • Examination of the possible role of biofertilizers and wood ash in the nutrient supply of plants
    87-95
    Views:
    82

    Some physiological effects of bacteria containing fertilizer and some wood ash were examined in the experiments. The minimization of the use of chemicals in agriculture has been an ongoing challenge. One option lies in the intenzification of soil life. The release of organic matters by the roots and bacteria play a significant role in the uptake of minerals. The main problem to usilize wood ash in agriculture is its heavy metal contents. The solubility of heavy metals is very low, therefore there is no risk to use the wood ash in the agriculture and in the horticulture according to our experiments. The wood ash and biofertilizer contains several micronutrients in an optimum composition for forestry and agricultural plants.

  • Nutrition reaction of different varieties of winter wheat (Triticum aestivum L.) bred in Karcag
    63-67
    Views:
    146

    In our study the nutrition reaction of four varieties of winter wheat (KG Bendegúz, KG Kunhalom, KG Kunkapitány, KG Széphalom) has been investigated. In the experiment the effect of twenty different nutrition doses on the yield and thousand kernel weight of the wheat varieties has been studied. Significant difference could be figured out among the yield and thousand kernel weight of the wheat varieties, so the choice of the proper variety determines the quantity of yield. KG Kunkapitány had the highest yield, while KG Széphalom had the highest thousand kernel weight in the experiments.

    Investigating the effect of the nutrients on the yield the conclusion was that all nitrogen doses had significant yield increasing effect compared to the untreated plots, but among the 40, 80 and 120 kg ha-1 doses there was no statistical difference. In the case of phosphorus the 40 kg ha-1 dose showed statistically verifiable increase of the yield, while potassium doses have no influence on the yields. The thousand kernel weights reached the maximum values where the highest nutrient doses were applied.

  • N-Phenyl-Phthalamic Acid and Fertilization Effects on Flowering, Fruit Set and Fruit Quality of Apple (Malus domestica Borkh.)
    24-28
    Views:
    121

    On seven apple cultivars (Gala Must, Gloster, Granny Smith, Idared, Jonagold, Jonathan Csány 1, Mutsu), the authors studied the influence of N-phenyl-phthalamic (PPA) acid and fertilization on flowering, fruit set and fruit quality in the years 2003-2004. The research results showed that PPA application extended the flowering time of the most cultivars. Fruit set of apple cultivars increased in many cases when regulator was applied. The additional nutrient supply could increase the fruit set too. The increase of fruit set increased the number of fruit per tree. Quality parameters determined by fertilization and fruit number per tree. For example, when N-phenyl-phthalamic acid was applied without fertilization the fruit number per tree increased considerably however, it caused a considerable frittering away. The reason for this is that fruit set was high and fruit received not enough nutrition for growing up. The skin colour of fruits was decreased in several cases by the treatments. In one respect the enlarged fruit number was shaded the others and the fertilization increased the vegetative shading leaf area.

  • Grassland association stock of plants the examination of the regeneration of a construction
    185-191
    Views:
    35

    Due to the drastic change in using the nature like grassland association (one-sided overgrazing – one mowing per a year), by the third year of the experiment in every area, where overgrazing stopped, independently on second sowing and nutrient resupply, Borhidi degradation degree decreased. In the areas where overgrazing with large animal density (sheep) continued, degradation degree was 3.4–5.0 by the third year of the experiment, and Hordeum murinum, which causes animal healthy problems, appeared massively.

  • Evaluation of long term experiments from a new aspect
    55-60
    Views:
    118

    During our work, we developed a new, simple method to show the effects of fertilization on yield, which can both be applied over the long term as well as in series of independent experiments.
    During the testing of this method, at the experimental farm of the Debrecen University Center for Agricultural Sciences at Látókép on a chernozem soil with lime deposits, we examined the fertilizer reaction of maize hybrids between 1989 and 1994. The treatments were: winter tillage, plant density of 70-80 thousand, unfertilized, N 120, N 240 kg/ha fertilized treatments, long term experiments using Dekalb 524 and Volga SC hybrids in long term experiments.
    Four parameters are shown in the model. In the examined period TRmax represents the greatest yield in the fertilized treatments, NT the yield in unfertilized treatment, k the „efficiency of fertilizer” to NT and b the depression-coefficient, where the expected value is zero. The expected grain yield of the fertilized treatments (Y), in the function of the unfertilized grain yield (x) is the following:

    The parameters were determined using the Monte Carlo method, in the optimizing process the sum of deviation square was minimized. The correct conformation of the functions was determined by the greatness of the R-value and the standard error. We found that during six years of testing, the tendency of fertilization efficiency was similar in the case of both hybrids. There was an unfavorable weather interval and, in these years, the yields were low, fertilization did not have an effect and moreover, in extremely bad conditions resulted in an obvious yield decrease. With the  improvement of conditions, which in the case of our country means an increase in precipitation, the efficiency of fertilization increases and reaches its peak at 13-14 t/ha. At this point, the yield increasing effect of fertilization is 4-4,5 t/ha. If the yield of the unfertilized treatments increases from 8-9 t/ha, then the efficiency of the applied fertilizer decreases.
    Most likely, the k and b parameters depend on the soil of the experimental location (nutrient and water management) and on the amount of  pplied fertilizer and the characteristics of the  hybrid. With the increase of fertilizer dosage the k-parameter also increases. The greater value though does not obviously mean a more favorable situation. It is true that in medium and good years this means great fertilizer efficiency, but in low or extreme precipitation conditions it also means greater risk. With the increase of the k-parameter, the yield deviation also increases which, from a cultivation point of view, is quite unfavorable. If the value of the b-parameter is other than, zero then the effect is clearly unfavorable, because with the increase of this value, the yield decrease is also greater. The fertilizer reaction of the two examined hybrids can be well characterized by these two hybrids.
    Examining the six years, our created model estimated the effect of fertilization on the yield accurately and with a high degree of safety. Both in highly unfavorable and extremely good years, it gave an exact estimate. In our opinion, it can be used well to evaluate the effects of fertilization on yield in the future.

  • Compost application in integrated and organic fruit cultivation
    135-139
    Views:
    118

    Nowadays the success vegetable and fruit production are unimaginable without regular nutrient management. One of the ways to supply the required nutrients in an environmentally friendly way is the application of composts, which is less widespread so far. Compost doses were applied in biological and integrated apple orchards in cooperation with the Institute of Horticultural Science in the years 2010 and 2011. Different changes were resulted by the compost treatments in the examined parameters in case of both apple varieties (Golden Delicious and Pinova). There is no clear effect of compost on the changes of ash-, total acids, Vitamin C and the sugar content until now, because the improvement of the nutritional indicators takes more time. However significant differences were observed after one year between the apple varieties. Higher ash-, total acids and sugar content were measured in case of the apple variety Pinova, while the measurements showed higher Vitamin C content in case of the variety Golden Delicious.

  • The effect of supplemental pig milk replacer on carbohydrate metabolism – a review
    67-71
    Views:
    216

    The aim of this review is to examine the effect of milk supplementation on pigs’ carbohydrate metabolism. These parameters regulate the growth of piglets, the nutrient intake and the period of pre-weaning. Due to the increased litter size, the sow milk yield reaches an individual maximum. The individual maximum has not increased proportionally with the number of piglets born alive. The use of liquid milk supplementation may give the opportunity to keep these large litters. The examined hormones are insulin, insulin-like growth factor, growth hormone, growth hormone releasing hormone, ghrelin and leptin. This review seeks to find these hormones’ interactions.