The yielding capacity and quality parameters of 11 maize hybrids were studied in 2011 on calcareous chernozem soil in a 25-year long-term fertilization experiment in the control (without fertilization), in the base treatment of N 40 kg ha-1, P2O5 25 kg ha-1, K2O 30 kg ha-1 and in... five treatments which were the multiplied doses of the base treatment. The N fertilizer was applied in the autumn and in the spring, while P and K fertilizers were applied in the autumn.The sowing time was 17–18 April, the time of harvest was 8 October. The 30-year average of precipitation (April–Sept) was 345.1 mm, the amount of precipitation did not differ greatly from that, however, its distribution was very unfavourable.
It was found that the largest yield increment (as compared to the control) was in the treatment N 40 kg ha-1, P2O5 25 kg ha-1, K2O 30 kg ha-1 in the long-term experiment. The largest yields were obtained for the hybrids P9494, PR37N01 and PR35F38 (13.64–13.71 t ha-1). Due to the dry period at the end of the summer – beginning of autumn, the grain moisture content at harvest was favourably low, 12–18% depending on the treatment and the growing season.
The N fertilization significantly increased the protein content of the kernel, but the starch content of the kernel decreased (significantly in several cases) with increasing fertilizer doses and yields as compared with the control.
The highest protein content was measured in hybrids GK Boglár and Szegedi 386. The oil content was above 4% for GK Boglár, but the two hybrids were not among the best yielding hybrids in spite of their good inner content. The starch content was around 75 % without fertilization, it decreased with fertilization.
For the tested hybrids, the fertilizer dose N 120 kg ha-1, P2O5 75 kg ha-1, K2O 90 kg ha-1 can be recommended with respect to efficacy and environmental considerations.
In precision nutrient management the most important aspect is adaptation but we should consider the possibility of the long-term improvement of soil fertility within the less fertile landscape zones. This possibility can be evaluated principally by long-term field experiments, which are running on similar soil types. The results of these...field experiments can indicate that which soil fertility status should be attained. Some more important soil fertility data, (such as pH, P-, K- and soil organic matter (SOM) content) of a long-term field experiment with increasing farmyard manure(FYM) doses or equivalent NPK fertilizers, set up on an Eutric cambisol, are presented. The yieldincreasing capacity of FYM doses was only 82%, as compared to the equivalent amount of mineral NPK, but long-term FYM treatments resulted in 10% higher SOM content than that of equivalent NPK
fertilizer doses. The studies indicate that SOM content is a function of local climate and clay content of the soil, and neither long-term high FYM doses can increase SOM content steadily above a supposed steady-state value. However we have to make efforts to keep the optimum level. The lowest soil reactions developed both with the highest NPK doses and without any fertilization. AL-P2O5 content of soil was increased more by mineral fertilization than by FYM treatments, but in case of AL-K2O content there was no difference between the fertilization variants. However the highest doses of both fertilization variants increased soil nutrient content to an excessive degree. Wecould get very valuable data from the unfertilized control plots as well, where long-term yield data suppose 48 kg ha-1 year-1 air-borne N-input.
In our research we examined the effect of the hybrid, the nutrient supply, the number of plants and the abiotic factors (temperature, amount of precipitation) on the yield, crop quality and yield stability of maize. We devoted special attention to the natural nutrient utilization ability and fertilizer reaction of maize.
The experiment...took place in Hajdúszoboszló on chernozem soil, on a nearly 8 ha field. The size of one plot was 206 m2, this it was a halfindustrial experiment. We tested six hybrids with different genetic characteristics and growing seasons. I analysed the correlation between the nutrient supply and the yield of maize hybrids with control treatment (treatment without fertilization) and with N 80, P2O5 60, K2O 70 kg ha-1 and N 160, P2O5 120, K2O 140 kg ha-1 fertilizer treatments. Yield increasing effect of the fertilizer also depended on the number of plants per hectare at a great extent. The number of plants of the six tested hybrids was 60, 70, and 80 thousand plants/ha.
In Hajdúszoboszló, in 2015 the amount of rainfall from January to October was 340.3 mm, which was less than the average of 30 years by 105.5 mm. This year was not only draughty but it was also extremely hot, as the average temperature was higher by 1.7 °C than the average of 30 years. In the critical months of the growing season the distribution of precipitation was unfavourable for maize: in June the amount of rainfall was less by 31mm and in July by 42 mm than the average of many years.
Unfavourable effects of the weather of year 2015 were reflected also by our experimental data. The yield of hybrids without fertilization changed between 5.28–7.13 t ha-1 depending on the number of plants.
It can be associated also with the unfavourable crop year that the yield of the six tested hybrids is 6.33 t ha-1 in the average of the stand density of 60, 70 and 80 thousand plants per hectare without fertilization, while it is 7.14 t ha-1 with N80+PK fertilizer treatment. That increase in the yield is only 0.81 t ha-1, but it is significant. Due to the especially draughty weather the yield increasing effect of fertilizers was moderate. In the average of the hybrids and the number of plants, increasing the N80+PK treatment to N160+PK, the yield did not increase but decreased, which is explicable by the water scarcity in the period of flowering, fertilization and grain filling.
The agroecological optimum of fertilization was N 80, P2O5 60 and K2O 70 kg ha-1. Due to the intense water scarcity, increased fertilization caused decrease in the yield. As for the number of plants, 70 000 plants ha-1 proved to be the optimum, and the further increase of the number of plants caused decrease in the yield.
Agricultural management practices – directly or indirectly – influence soil properties.
Fertilization rates and crop rotation can strongly affect soil pH, soil nutrient supply and soil organic matter content due to the changes of microbial processes. The objective of this study was to compare the effects of different fertilization d...oses in monoculture and tri-culture of maize (monoculture: only maize grown since 1983, tri-culture: it is a three-year crop rotation system: pea – winter wheat – maize) on selected soil characteristics. The long-term fertilization experiments were set up in 1983 in Eastern Hungary. These experiments are situated west of Debrecen in Hajdúság loess region, on calcareous chernozem (according to WRB: Chernozems).
The test plant was maize (Zea mays L.). One-one pilot blocks were selected from monoculture and tri-culture of the long-term experiments. The observed soil samples were taken in the 30th year of the experiment, in 2013. The doses of NPK fertilizers increased parallel together, so the effects of N-, P- and K-fertilizers cannot be separated.
With the increasing fertilizer doses, the soil pH has decreased in both crop production systems and, in parallel, the hydrolytic acidity has significantly increased. A close negative correlation was proved between the pHH2O, pHKCl and hydrolytic acidity. An increased nutrient content in soil was recorded in every NPK treatment and the available phosphorus and nitrate content increased in higher proportion than that of potassium. Of the measured parameters of C-and N-cycles, fertilization has mostly had a positive effect on the microbial activity of soils. Besides the effects of fertilizer doses, correlation were looked for between soil microbiological properties. Evaluating the ratios among the measured parameters (organic carbon and microbial biomass carbon, OC/MBC ratio; carbon-dioxide and microbial biomass carbon; CO2/MBC proportion), the fertilization rate seems to be favoured by the increase of amounts of organic compounds
The objective of this study was to evaluate the impact of long term NPK fertilization (considering that S containing superphosphate was supplied for 26 years of experiment, but since 9 years S has not used any longer) on sulphur- and nitrogen content and N/S ratio of winter wheat. The second objective of this work was to determine the chang...es of the amount of the different nitrogen and sulphur fraction in chernozem soil in a long term fertilization experiment. The third aim of the work was to determine if a relationship could be established between the studied parameters. Based on our results, it can be stated that the sulphur containing superphosphate supplied in the period of 1984-2010 has no longer significant effect on total sulphur content of plant in 2018. The NPK fertilization treatments had positive effect on total nitrogen content of winter wheat. In general, increasing NPK doses resulted in significantly higher nitrogen. The effect of irrigation applied in previous years has no statistically significant effect on the sulphur and nitrogen content of wheat. The wheat grain produced in our experiment, especially in fertilized treatments showed S deficiency. Analysing the changes of CaCl2 soluble nitrate-N and total N of the soil, it can be stated that the effect of increasing fertilizer doses clearly appears in these parameters, because the treatment with increasing fertilizer doses resulted higher CaCl2 soluble N forms compared to the control treatment in soil. These values increased until flowering stage of wheat and after that a slightly decrease was observed as a result of higher N uptake of plant. In overall, it can be stated, that the effect of superphosphate on measured sulphur fraction is prevailed. With increasing fertilizer doses higher sulphate content was detected in soil, but the sulphate content measured in different soil extractant is not enough for the wheat in this experiment area. Studying the correlation between the measured parameters of plant and soil, it can be concluded, that the relationships between nitrogen in the plant and in the soil is stable, and did not change during the growing season. The correlation between plant S and soil S varied in the measured periods and the r value was low in most cases. At the stage of flowering the highest r value was found between KCl-SO4 and plant S. In the stage of ripening the strongest correlation was detected between KH2PO4-SO4 and grain S content.
In pot experiment the effect of different microbial inoculants and their combinations with NPK fertilizer and wheat straw on some soil properties (physical, chemical, and microbiological parameters) were studied. The experiment was set up in 2011 at the Institute of Agricultural Chemistry and Soil Science, in a three replications, in a random b...lock design. The studied soil type was calcareous chernozem soil from Debrecen (Látókép) with ryegrass (Lolium perenne, L.) test plant.
At the end of the experiment in our laboratory the nitrate-nitrogen content of soil, the AL-soluble phosphorus and potassium content of soil, the urease enzyme activity of soil, the total number of bacteria and the number of microscopical fungi were determined.
The results of the study were the following:
– The straw treatment and the straw + biofertilizer combinations influenced positively the nitrate content of soil.
– The NPK fertilization and the straw+bacterial fertilizer combinations had significant positive effect on the AL-soluble phosphorus content of the soil.
– The biofertilization and the straw+biofertilizer combinations stimulated the AL-soluble potassium content of soil occasionally.
– The total number of bacteria was influenced by the NPK fertilization, the bacterial fertilization and the straw+bacterial fertilizer combinations significantly.
– In case of the number of microscopic fungi caused in some cases significant changes the NPK+bacterial fertilizer and straw+bacterial fertilizer combinations.
– The soil urease enzyme activity was increased in all cases strongly especially by the straw+bacterial preparation combinations.
In pot experiment the effect of Amykor and Organic Green Gold bioproducts and their combinations with NPK fertilizer on some soil properties (chemical parameters) and on the biomass of testplant were studied. The experiment was set up in 2012 at the Institute of Agricultural Chemistry and Soil Science, in a three replications, in a random block... design. The studied soil typein the pot experiment was humus sandy soil from Debrecen-Pallag with onion (Allium cepa) test plant. At the end of the experiment (after 4 week) in our laboratory the samples of soil and plant were determined. The nitrate-nitrogen, AL-soluble phosphorus and potassium content of soil, the weight of green onion leaves, the wet weight of bulb and root of onion and biomass of onion. The results of the study were the following: – The treatments influenced positively the nitrate-nitrogen, the AL-soluble phosphorus and potassium content of soil. – The most effective treatments were the artificial fertilization (NO3-N) and the NPK+ simple dose of Amykor (AL-P2O5 and Al-K2O). – The NPK fertilization and the NPK+OGG (sprinkle in every 10 days) combinations had significant positive effect on the weight of green onion leaves. – The biofertilization and the straw+biofertilizer combinations stimulated the AL-soluble potassium content of soil occasionally. – The OGG treatment (sprinkle in every 10 days) had significant effective impact on the wet weight of bulb and root of onion. – The biomass of onion was increased by the artificial fertilization and OGG (sprinkle in every 10 days) treatment.
Sowing time, nutrient supply and plant number play crucial roles in the yield stability of maize. The productivity of various hybrids, each with its own genetic characteristics, was tested for three different sowing times and five different fertilizer doses. The highest yields were achieved at the third sowing time (17. V.), which is unusual, b...ecause the second half of the summer was rainy and was favourable for late sowing. The seed moisture content at harvest was higher than the optimal 14-15% at the third sowing time, the hybrids, which have intensive bleeding dynamics, couldn’t reach the lower seed moisture content at harvest of the early sowing. In that case we have to decision whether the plus yield of the third sowing time cover the drying costs.
Some hybrids produced the highest yields by N 120, P2O5 75, K2O 90 kg/ha active agent but the higher fertilizer doses depress the yield. The other part of the hybrids were able to produce high yield by bigger fertilizer doses. On the whole the agro-ecological optimum of the NPK fertilization was N 120-160, P 25-100, K 90-120 kg/ha active agent, but the N 80, P2O5 50, K2O 60 kg/ha fertilizer doses was the most effective.
The Limagrain maize hybrids in different maturity groups were examined at the Látókép Experimental Station of the Centre of Agricultural Sciences and Engineering, University of Debrecen on a calcareous chernozem soil with loam texture, between 2001 and 2007 in a multifactorial long-term field trial. Doses of fertilizers: 1 N:0.75 P2...b>O5:0.88 K2O fixed proportion of NPK doses. The basic dose of nitrogen is 30 kg ha-1. The application of fertilization was 1, 2, 3, 4, and 5 times more than the basic dose, beside of untreated control. The long-term field trial is performed in none irrigated and in irrigated version.
The goal of the study was to analyze the effect of precipitation (environment factor) in one hand, and to evaluate the effect of fertilization and irrigation (agrotechnical factors) on the yield of maize hybrids in different maturity groups in the other hand. At the same time I studied the effect of interaction of different factors on the yield of maize.
Analysis the yield of Limagrain hybrids revealed: the years considerably affected the level of the yield. In dry years the yield was 1.351 t ha-1 less, than in rainy years. As the effect of fertilization the yield increased, the statistically proved biggest increment was at level of 90 kg N ha-1. Evaluating the maturity groups, FAO 300 hybrids reached higher level of yield.
In non irrigated conditions in the average of the seven years 60 kg N ha-1 was sufficient to reach the maximum yield. The efficiency of fertilization on yield in irrigated version increased, 120 kg N ha-1 assured the reliable level of yield.
Without irrigation in comparison to the results of FAO 200 group, with the growth of FAO numbers the yield is increasing in all cases. The most significant increase was at FAO 300 (3.562 t ha-1). With irrigation the greatest difference in yield was in FAO 400 (+2.720 t ha-1) compared to FAO 200.
The experiment was carried out in Debrecen, at the Experimental Station of the University of Debrecen Centre of Agricultural Sciences, Department of Crop Production and Applied Ecology. We tested 10 various hybrids with their own genetic characteristics for five different fertilizer doses, in addition to the parcels without fertilization. The t...hree factors of production technology jointly determine the successfully of maize production, but in different measure. The yield and the stability of yield of maize can be increased with hybrid-specific technologies.
In 2004-2005 experiment years the favorable results reached were due to the rainy season. There were significant difference between the productivity of maize hybrids. The N 40, P2O5 25, K2O 30 kg/ha treatment caused the highest increase of yield (3-5 t/ha) compared to the control (parcels without fertilization). The reaction of hybrids to the further fertilizer doses was different. The agro-ecological optimum of NPK fertilization was N 120, P 75, K 90 kg of the most hybrids.
During the experiment, we tested the moisture loss of the five hybrids. The seed moisture content at harvest was higher than in previous years due to the rainy seasons. The seed moisture content of harvest of FAO 200-300 hybrids were about 20%. It changed between 21-24% in the case of hybrids with longer vegetation period (FAO 400), the seed moisture content of Mv Vilma (FAO 510) was 24.21-25.04% in the average of fertilizer treatments. There is an important difference between the moisture loss ability of hybrids which changed 0.2-0.6%/day. The moisture loss of hybrids changed depending on the fertilizer treatment; usually, it was more favorable in the optimal fertilizer dose (N120+PK).
In the case of tested hybrids, we measured the highest LAI and photosynthetic activity at the optimal treatment, N 120, P2O5 75, K2O 90 kg/ha in the respect of efficiency and environmental protection, and the yield was high also for this treatment. There are significant difference between the LAI, the photosynthetic activity and the yield of hybrids, and these values could change depending on the treatment of fertilization.
The effect of Zn fertilization on the yield and Zn, N, P, K, Mg and Mn content of ryegrass was studied in a greenhouse experiment for 8 chernozem soils with three replicates under uniform NPK supply and irrigation. The applied Zn rates were 0, 2.5 and 5 mg/kg Zn. Due to Zn doses the yield incrased significantly. Zn fertilization increased the p...lant Zn content and decreased the plant P and Mn content significantly. For N, K and Mg there was no significant effect.
...5); font-variant-ligatures: normal; font-variant-caps: normal; -webkit-text-stroke-width: 0px; text-decoration-style: initial; text-decoration-color: initial;">The paper presents research results obtained in stationary experiments, carried out at Agricultural Research and Development Station Oradea, regarding the influence of nitrogen, phosphorus and potassium fertilizers, on Cd, Pb, Cu, Zn and Ni concentration on wheat grains.
...5); font-variant-ligatures: normal; font-variant-caps: normal; -webkit-text-stroke-width: 0px; text-decoration-style: initial; text-decoration-color: initial;">In this study the effect of N, P and K nutrients on the Cu and Fe content of winter wheat (Triticum aestivum L.) grains was investigated in a long-term fertilization experiment set up in Nagyhörcsök. Samples were also harvested from four experimental stations of the Hungarian national long-term fertilization trials. These are the following: Bicsérd, Iregszemcse, Karcag, and Putnok. Plant samples were collected in 2005 which was very wet. Our results from Nagyhörcsök were compared with the Cu and Fe content of samples which were harvested from control plots of other experimental stations. The Cu and Fe content of grain samples were measured using inductively coupled plasma mass spectrometer (ICP-MS) followed by digestion with HNO3-H2O2 solution. All data were subjected to ANOVA, and when significant differences (P<0.05) were detected, Duncan’s test was performed to allow separation of means.
Several factors influence the quantity and stability of maize yield, the most important being the nutrient supply, the hybrid and precipitation. In 2004, during the maize growing season the precipitation was more than the 30 year’s average, with 68.3 mm, but the distribution was unfavorable. The experiment was carried out in Debrecen at the E...xperimental Station of the University of Debrecen Centre of Agricultural Sciences, Department of Crop Production and Applied Ecology. We tested 10 various hybrids with their own genetic characteristics for five different fertilizer doses, in addition to the parcels without fertilization.
The favorable results reached were due to the rainy season. The average yield varied between 7.78-9.67 tha-1. The DK 440, PR37M34, PR38A24, PR39D81 and PR36R10 of the hybrids reacted to higher fertilizer doses with significant growth yields, the yield (more than 11 tha-1) was the highest for N200, P125, K150 fertilizing. The other hybrids, DKC 5211, Mv Vilma and MV Maraton, gave similar results at the N120+PK fertilizer dose and the ensuing doses depressed the yield. Fertilization was more effective thanks to the precipitation. The fourth and fifth dose increased or decreased maize yield depending on the nutrient reaction of the hybrid. The agro-ecological optimum of NPK fertilization was N120, P75, K90 kgha-1.
During the experiment we tested the moisture loss of five hybrids. The rainy crop year’s effect on the seed moisture content at harvest was higher than in previous years. The seed moisture content hybrids at harvest which have shorter crop years (FAO 300) was 18-19%, and hybrids with longer vegetation periods had more than 20% seed moisture content. DK 440 hybrid had the intensive moisture loss of the five hybrids, at the start of the measurement, the seed moisture content was higher than 40%, and it decreased to 18.6% by harvesting.
For industrial (bioethanol) production of maize, a new production technology is needed. I tested and selected hybrids appropriate for this purpose and set up fertilization and plant density experiments. The experiment were set up on chernozem soil in 2008.
In bioethanol production, the selection of a high-yielding hybrid with high starch con
The aim of our two year study is to research the effect of nutrient supply on apple fruit quality, and to explore the relationships between selected fruit quality parameters.
Observations were made in Kálmánháza (in the eastern part of Hungary), on a commercial apple orchard. In this experiment, we studied the nutrient supply reaction of
The research results showed that N fertilization has a great effect on fruit quality. This is shown in the cases of increase of fruit size (fruit diameter, fruit height, fruit weight). The increase is proportional with the N doses, accordingly the highest positive difference was observed by using 100 kg/ha N doses. It is important to note that moderate N doses (75 kg/ha) plus P and K additions also had positive effects. There approached the values of 100 kg/ha N, and even exceeded its values in the cultivar Golden Reinders. The increased N doses enlarged the standard deviation, on the other hand, this parameter was low in the cases of balanced NPK fertilization. The nutrient supply increased the vegetative area (density of foliage) in addition to the generative parts, in particular only N fertilizer. However the denser foliage hindered the growth of fruit weight and colour-coverage, and also decreased the fruit quality and the flesh firmness of cultivars, which have a negative effect on storageability.
A linear correlation was demonstrated between the fruit weight and colour-coverage, or between fruit weight and flesh firmness. The character of their relationship was similar, but the direction differed: high fruit weight was with high colour-coverage, but with low flesh firmness.
The effect of wheat straw ash as a fertlizizer was studied in a pot experiment with an acidic sandy loam soil (pHKCl=4.9) with weak K and P supply. The test plant was ryegrass (Lolium perenne). The treatments were the following: 1. control untreated soil, 2. NPK fertilizer, 3. small dose of ash (1.4 g kg-1), 4 large dose o...f ash (2.8 g kg-1), 5. small dose ash completed with NP fertilizers. Soil parameters (pHH2O, pHKCl, ammoinum-lactate soluble P, K, 0.01 M CaCl2 soluble PO43--P, K, Mn, Cu, Zn ) and plant parameters (yield, P, K, Ca, Mg, Zn, Mn uptake) were investigated. Based on the analysis of the straw ash sample and the results of pot experiment it can be stated that the wheat straw ash is suitable for the fertilization of the studied soil. The small dose ash completed with NP resulted in the largest yield increment (43%). In order of the treatments the pHKCl changes to: 4.9, 4.8, 5.2, 5.8, 5.1. As the N : P2O5 : K2O ratio is 0 : 1: 3.5 in the wheat straw ash sample, to reach optimal yield ash should be completed with N and P.
...5); font-variant-ligatures: normal; font-variant-caps: normal; -webkit-text-stroke-width: 0px; text-decoration-style: initial; text-decoration-color: initial;">The yield and quality of wheat are mainly determined by the plant production system, thus we studied the effect of mineral fertilization.
The aim of this work was to evaluate the changes of different sulphur forms (soluble, adsorbed) in chernozem soil in a long-term field experiment supplied with increasing doses of NPK fertilizers for a long time. In addition, other objective of this study included the examination of the applicability of recommended extractants of the different...sulphate fraction in Hungarian soils. A long-term field experiment was established at the Research Station of Látókép of the University of Debrecen in 1984. In addition to control, two levels of NPK fertilizer doses have been used with irrigated and non-irrigated variants. Winter wheat and corn were cropped in a crop rotation on plots. Soil samples were collected in three different development stages of winter wheat, at the stage of stem elongation (April), flowering (May) and ripening (June of 2018) from the topsoil (0–20 cm) of experiment plots. Water-soluble inorganic sulphate was extracted with 0.01M CaCl2 solutions. The soluble plus adsorbed sulphate was extracted with 0.016M KH2PO4 solution. Sulphate was measured by turbidimetric method. 0.01M CaCl2-SO42— ranged between 0.293–1.896 mg kg-1 and the 0.016 M KH2PO4-SO42- varied between 5.087–10.261 mg kg-1. The values of KH2PO4 SO42- was higher than that of CaCl2-SO42-, because KH2PO4 extracted the adsorbed and soluble fractions of sulphate, while CaCl2 extracted the soluble sulphate fraction. The amount of absorbed sulphate was calculated by the differences of KH2PO4- SO4 and CaCl2-SO4. The KH2PO4 characterizes mainly the adsorbed sulphate fraction much more than the water-soluble fraction. KCl is the most widely used extractant for the determination of plant available sulphate content of soil in Hungary; therefore, KCl-SO42- fraction also was determined. The KCl-SO42- ranged between 0.328–2.152 mg kg-1. The CaCl2-SO42- and KCl-SO42- fractions were compared and based on Pearson's linear correlation, moderate correlation was established (r=0.511) between them. In all three extractant (0.01M CaCl2, 1M KCl, 0.016 M KH2PO4) higher sulphate fractions were measured in the fertilized plots where superphosphate had been supplied for ages until 2010. The arylsulphatase activity of soil also was determined and ranged between 9.284 and 26.860 µg p-nitrophenol g-1 h-1. The lowest value was observed in the treatment with highest NPK2 dose, both in irrigated and non-irrigated areas.
The yield safety of maize has not been satisfactory in Hungary for decades. Yield is influenced by the combination of several factors.
In recent years, the frequency of dry years increased and fertilization decreased. These factors call for a rational determination of the plant density.
I studied the relationship between plant density and
In 2003, the weather was dry. In the vegetation period, the amount of precipitation was 78.5 mm lower and the temperature was 0.97 °C higher than the average of 30 years, the number of hot days was 47-60 (days with a temperature higher than 30 °C). However, we obtained favourable results under experimental conditions in 2003 after wheat as a forecrop using the fertilizer Kemira Power.
The weather in 2004 was favourable. In the vegetation period, the amount of precipitation was 93.2 mm higher than the average of 30 years. Although, the distribution of the precipitation could have been more favourable. The yield of the hybrids ranged between 8.87-10.42 t/ha. Among the studied seven hybrids, the early hybrids gave the highest yield at the highest plant density of 90 thousand plants/ha (PR38Y09, PR38A67, PR37D25, PR37M34). However, FAO 400-500 hybrids gave favourable results also at the low plant density of 45 thousand plants/ha (8-9 t/ha). At this plant density, the aeration of the plant stock was better and the hybrids were prone to bringing several cobs. Yield stagnated with increasing plant density (60 thousand plants/ha), then at 75-90 thousand plants per ha, the yield started to increase again.
In 2004 the yield of hybrids was considerably higher than in the previous year. In contrast to yields of 8.87-10.42 t/ha in 2003, yields in 2004 were around 9-12 t/ha.
The yield of the hybrid XO 902 P is above 12 t/ha already at a plant density of 45 thousand plants/ha. It gives maximum yield at the plant density of 90 thousand plants/ha.
The hybrid PR38P92 showed a good response to changing plant density, but its yield was only 9 t/ha at the low plant density value.
In a favourable year, the yield of the hybrids PR38B85, PR37W05, PR37D25, PR37K85 at a plant density of 45 thousand plants/ha 11 t/ha, while at the higher plant density of 90 thousand plants/ha, it ranges around 13-15 t/ha.
Hybrids PR36K20, PR35Y54, PR34H31 have a good individual yield and they are prone to bringing several cobs in favourable years at a low plant density. Their maximum yield at the plant density of 90 thousand plants/ha is almost 16 t/ha.
In 2007, the weather was similar to that of the extremely dry year of 2003. The amount of precipitation in the vegetation period was 41.9 mm lower than the average of 30 years and its distribution was not favourable either.
In the optimum NPK fertilizer treatment at an optimum plant density, the yield of hybrids ranged between 9.32-10.73 t/ha. The highest yields of 10.22-10.73 t/ha were measured for hybrids PR38A79 (FAO 300) and PR35F73 at a relatively low plant density of 60 thousand plants/ha.
In the average of the hybrids, the optimum NPK dosage was N 131, P2O5 82, K2O 93 kg/ha active ingredient.
The effect of fertilization on the yield of maize was examined on chernoem soil with lime deposits at the experimental station at Látókép of the Center for Agricultural Sciences, University of Debrecen. The yields of maize were evaluated using quadratic regression function, in three years – between 2000 and 2002 – in non-irrigated and ir...rigated treatments. After calculating the regression equations, by derivation of the functions, we have determined the amount of fertilizers needed for maximum yield.
In the non-irrigated treatments, maximum yield and the active substance amount of fertilizer was as it follows: in 2000, yield of 9,133 t/ha with the application of 384 kg/ha mixed active substance, while in 2002 a yield of 6,289 t/ha with the application 236 kg/ha NPK active substance was achieved. In 2001, due to the favourable precipitation, a yield of 9,864 t/ha was achieved with the application of 245 kg/ha fertilizer. In the case of maximum yield, compared to the unfertilized control, the yield increase was 2,5-5 t/ha. The average increase for 1 kg of NPK fertilizer was 13-19 kg.
We also determined the necessary fertilizer dosage for maximum yield in irrigated treatments. In 2000, 10,003 t/ha with a dosage of 423 kg/ha, in 2001, 11,542 t/ha with a dosage of 277 kg/ha and in 2002, 8,596 t/ha of maximum yield could be achieved with a fertilizer treatment of 277 kg/ha in the examined three years. The yield increase, in irrigated treatments, varied between 3,9-5,9 t/ha so it was greater than in the case of non-irrigated experimetal plots. The yield increase for 1 kg fertilizer varied between 12-21 kg.
In this study the effect of N,P and K nutrients on the S and protein content of wheat grains was investigated in a long-term fertilization experiment set up in Nagyhörcsök. The calcareous chernozem soil having the following characteristics: pH (KCl): 7.3, CaCO3: 4.27%, humus: 3.45%, Al-soluble P2O5 and K2...O: 60–80 and 180–200, KCl- Mg: 150–180, KCl+EDTA-soluble Mn-, Cu- and Zn-content: 80–150, 2–3 and 1–2 mg kg-1. The experiment had a split-split-plot design with 40 treatments in 4 replications. Plant samples were collected from 2002 and 2004. 2002 was a drought year while 2004 was very wet.
The main conclusions are as follows:
– The sulphur and protein content were than the control higher in every NPK treatments.
– The sulphur and protein content of the wheat grains were higher in 2004 that had a lot of rain than in 2002 that had drouht.
The experiments were set on lime-coated chernozem soil in 2013 and in 2014, in our study four hybrids were included with different FAO number. We studied the effect of NPK fertilization and row spacing on the yield. The fertilizer doses were based on a 25-year longterm experiment. Compared to control, the N40 +PK treatment has also achieved a s...ignificant yield increase, although some hybrids responsed with yield loss to the increasing fertilizer doses; this effect was observed especially in 2014. The majority of hybrids reached higher yields in both years using the 50 cm row spacing. The water release of hybrids was measured weekly during the maturation, at the same time points. The rainy September slowed ripening and the water release of the hybrids in 2013, so the grain wet content at harvest showed higher values. The moisture contents were increased for some hybrids, in spite of the positive and favorable dynamic of water loss.
In 2015 eight, in 2016 ten hybrids with different genetic characteristics and growing seasons, with control (without fertilization), N80+PK and N160+PKtreatments, five plant densities (50–90 thousand) with 10 thousand plants difference between the different densities.