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.
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 a long-term field experiment set up at the Látókép experimental station of the Center of Agricultural Sciences of Debrecen University, the data of the last five years (1995-1999) were analyzed to determine the crop production factors with the greatest influence on maize production and the relationship and interactions between irrigation a...nd fertilization.
In the extremely dry year of 1995, fertilization was found to cause substantial yield depression in the absence of irrigation. According to results of analysis of variance, fertilization significantly reduced the maize yield by 40-90% compared to control plots. Under irrigated conditions, there was a considerable increase in the maize yield, the yield surplus being 4.4-9.4 t ha-1, depending on the nutrient supply level.
During the period from 1996-1999, when rainfall conditions were favorable for maize, fertilization significantly increased the maize yield even without irrigation over the average of the four years. The yield surplus due to fertilization was 3.9-4.6 t ha-1, depending on the fertilization rates. The maximum yield surplus was obtained on plots fertilized with 120 N kg ha-1, while at the rate of 240 N kg ha-1 the maize yield did not differ significantly from this value. During the period examined, corn yield was significantly higher at all three nutrient supply levels as the result of irrigation than in the non-irrigated treatment. As in the case of non-irrigated conditions, the highest fertilizer dose did not result in a substantial yield increase. An analysis of the interaction between fertilization and irrigation indicated that the yield-increasing effect of fertilization was not significantly different under irrigated and non-irrigated conditions. The significant year x irrigation interaction was confirmed by the fact that the yield surplus (1.3-2.3 t ha-1) differed greatly from the irrigation effect recorded in 1995.
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.
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
Nowadays, due to the climate change, it is becoming increasingly important in the occasionally extreme years that the yield and the quality
parameters of a given winter wheat variety should not fluctuate at all or only slightly under similar agrotechnical conditions as a result of the year effect. In four years (2005–2008) we studied the c
In the control, it can be observed that the year had a significant effect on the wet gluten content, the protein content of the flour and gluten speading, therefore, a great fluctuation was detected in these qualities of the varieties in the four studied years. At the optimum fertilization levels (N120-150+PK), the varieties Sixtus, Saturus and Lupus showed a much lower fluctuation and more stable values were measured. The most stable variety in the control treatment was Mv Mazurka for all the three quality parameters, while at the optimum fertilization level (N120+PK), the most stable results were obtained for the variety Sixtus as an average of the four years.
When studying the results using Kang’s method for stability analysis, it can be stated that the most stable values of wet gluten content were obtained at the fertilization level of N120+PK under a variable year effect, the varieties gave also the best gluten content values at this level. The most stable protein content values of flour were obtained at the fertilization level of N60+PK. The results showed that the fluctuation of quality parameters as a result of the changing years differed between the different winter wheat varieties due to their differing genotypes, but this fluctuation could be reduced or minimized by a proper fertilization.
Effects of regular K fertilization and liming on the easily extractable K content of a Haplic phaeosem soil determined in 0.01 M CaCl2
and AL (traditional method in Hungary) were examined in the B1740 type of the National Uniformed Long-Term Fertilization Experiments
Close correlation (r=0.95) was found between the 0.01 M Ca
K fertilization increased the amount of 0.01 M CaCl2 and AL extractable K significantly. Liming had different effects on the amounts of
K extracted by these two methods. Liming increased the amount of AL-K and decreased the amount of CaCl2-K. CaCl2 extractable K was in
close correlation with the relative amount of exchangeable K content of the soil (K%) and the agronomic K balance. The results of regression
analysis confirmed that the CaCl2-K characterized K% and the AL-K related to the absolute amount of exchangeable K.
On the basis of the presented results it can be stated that the 0.01 M CaCl2 is able to detect not just the increase of easily extractable K
caused by fertilization and liming but the changing of the rate of the relative amount of exchangeable K.
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 experiments were carried out at the Látókép experimental station of the Centre for Agricultural Sciences of University of Debrecen on chernozem soil in a long term winter wheat experiment. As forecrop rotation, we set up two models: a biculture (wheat and corn) and a triculture (pea, wheat and corn). We applied three levels of nutrients...during the fertilization process (control, N50P35K40 and N150P105K120). The third variable studied was irrigation in case of which we tested non-irrigated variables (Ö1) and irrigation variables complemented up to the optimum (Ö3).
The effect of pre-crops, irrigation and nutrient-supply levels on some growth-parameters (LAI, LAD), weight of dry matter, just as SPADvalues and yield amounts of winter wheat has been investigated in this experiment. We tried to find out the extent of relationship between the different parameters, and we used the correlation analysis. The correlation analyses have confirmed that all of the investigated parameters had almost in all cases close positive correlation to the yield amount. These results have confirmed that the leaf area, the leaf duration, the SPADvalues, the fertilization and the forecrop have altogether resulted in the production of maximum grain yields.
The 30 years old long-term experiment of Látókép is continued in our experiments. The long-term fertilization experiment was set in 1983, and our sample was taken in spring 2014. The examinations of soil respiration processes and factors that influence soil respiration are required in optimal management. In our study, we interested to know h...ow the growing levels of fertilization influence the microbial processes under nonirrigated and irrigated conditions in maize mono, bi, and triculture. The experimental results and those statistics suggest that the bi and triculture influenced higher microbial activity which was reflected in number of fungus, soil respiration, and microbial biomass carbon (MBC).
In our researches, we examine the soil microbial parameters related to the carbon cycle. In this study, we compare the changes of microbial biomass carbon (MBC) and the soil CO2 production in soil samples which were taken in spring and autumn. The 30 years old long-term experiment of Debrecen-Látókép is continued in our experiment...s. The long-term fertilization experiment was set in 1983, and our sample was taken in spring 2014. The examinations of soil respiration processes and factors that influence soil respiration are required in optimal management. In our study, we interested to know how the growing levels of fertilization influence the soil respiration and microbial biomass carbon under non-irrigated and irrigated conditions in maize mono, bi, and triculture.
The experiments were conducted as part of the long-term trial adjusted, in triculture (pea-wheat-corn) and biculture (wheat-corn), at three nutrition levels, with the use of one crop protection technologie (conventional) at the Látókép Research Site of the Centre of Agricultural Scienses, University of Debrecen, on a chernozem soil. The whea...t variety used in the long-term trial was GK Csillag, which was sown at 5,8 million germs/ha.
The effect of pre-crops and nutrient-supply levels on some growth-parameters (LAI, HI, LAD), just as SPAD-values and yield amounts of winter wheat has been investigated in this experiment. We tried to find out the extent of relationship between the different parameters, so we determined the relationships between different nutrient-supply levels, yield amounts, LAI- SPAD- and LAD-values – measured in the crop-year of 2010–2011 in different crop rotation systems – by using correlation analysis. It has been stated both in case of bi- and tri-culture crop-rotation systems that different fertilizer dosages had significantly affected the leaf area index dynamics and its maximal value, and that increasing N+PK fertilization has
significantly increased the duration of leaves, as well. The highest SPAD-values were measured during the flowering and grain filling stages. However, we haven’t revealed significant differences between all fertilizer treatments. In case of the bi-culture crop-rotation system harvest index values showed an increasing tendency parallel to the increasing nutrient-supply levels, while in case of the tri-culture system this tendency was rather decreasing. However, these differences were
not significant. Parallel to the increasing fertilizer dosages yield results were increased in a significant extent. At the same nutrient supply-levels 2088–4615 kg ha-1 higher yields were measured in the tri-culture than in the bi-culture system. The correlation analyses have confirmed that all of the investigated parameters (yield amount, LAI, SPAD, LAD) had almost in all cases close positive correlation to the nutrient-supply level and the yield amount in both crop-rotation systems. These results have confirmed that the leaf area, the leaf duration, the SPAD-values and the fertilization have altogether resulted in the production of maximum grain yields.
We tested the fertilizer reaction of four different winter wheat varieties in three different crop years, on chernozem soil, in long-term experiment. We examined the optimum fertilizer requirements and the maximum yield of the varieties. According to our results there were significant differences among the years: the yield of the winter wheat v...arieties changed between 1.4–6.1 t ha-1 in 2013, 3.8–8.6 t ha-1 in 2014 and 3.2–8.6 t ha-1 in 2015. The yield increasing effect of fertilization was significantly different in the tested years. The optimum level of fertilization was determined by, besides the genetic differences among the varieties, the crop year and the extent of fertilization. In milder winter months, due to the higher average temperatures, yields of winter wheat increased compared to an average crop year.
In the crop season of 2010 (rainy year), we studied the effect of three agrotechnical factors (sowing time, fertilization, plant density) and four different genotypes on the agronomical characteristics of sweet corn on chernozem soil in the Hajdúság. The experiments were carried out at the Látókép Experimental Farm of the University of Deb...recen. In the experiment, two sowing dates (27 April, 26 May), six fertilization levels (control, N30+PK, N60+PK, N90+PK, N120+PK, N150+PK) and four genotypes (Jumbo, Enterprise, Prelude, Box-R) were used at two plant densities (45 thousand plants ha-1, 65 thousand plants ha-1). The amount of precipitation in the season of 2010 was 184 mm higher, while the average temperature was 0.8 oC higher in the studied months than the average of 30 years. Weather was more favourable for sweet maize at the first sowing date, if we consider the yields, however, if we evaluate the agronomical data and yield elements (number of cobs, cob length and diameter, the number of kernel rows, the number of kernels per row) it can be stated that the size of the fertile cobs was greater at the second sowing date due to the lower number of cobs. The largest number of fertile cobs was harvested in the case of the hybrid Enterprise (72367.9 ha-1) in the higher plant density treatment (65 thousand ha-1) at the fertilization level of N120+PK when the first sowing date was applied. The largest cobs were harvested from the hybrid Box-R (cob weight with husks: 516.7 g, number of kernels in one row: 45.7) at the lower plant density (45 thousand plants ha-1) in the second sowing date treatment. Cob diameter and the number of kernel rows were the highest for the hybrid Prelude.
...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.
The research topic has timeliness, since the rational utilization and protection of the soil, besides the conservation of its diverse functions is part of the sustainable development. Research of the long-term experiments is esentially important, because it can model the term effects in the same place, under the same conditions. If we want to g...et accurate informations about the occured changes, way and danger of changes, we should track the resupply and effect of the mineral nutrients and the removed quantity of nutrients with the harvest. Nitrogen is an essential element for living organisms, it is present in the soil mainly in organic form. In general only only a low percentage of the total nitrogent content can be used directly by plants in the soil. This inorganic nitrogen is produced by the transformation of organic contents through mineralization processes and it get into the soil by the fertilization. The plants incorporote the mineral nitrogen into our bodies. This is how nitrogen turnover is realized when mineral forms become organic and organic forms become mineral.
The purpose of our paper is to make a literature before our research.
Agriculture has traditionally an important role in Hungarian economy and rural development. About 75 % of Hungary’s total territory
is under agricultural land use. Because of ecological conditions and production traditions cereals (wheat, maize etc) have the greatest
importance in Hungarian crop production. In the 1980’s the country-a
crop production-model). In the 1990’s the yields of wheat dropped to 4,0 t ha-1 because of low input-using and wide application of the issues
of environmental protection and sustainability. Winter wheat production for quality has a decisive role in certain regions of Hungary
(eastern and middle-parts).
The quality of wheat is complex and different. Three major growing factor groups determine the quality of winter wheat: genotype,
agroecological conditions and agrotechnical factors. In wheat production for quality the selection of the variety is the most important
element. Our long-term experiments proved that the quality traits of a variety means the highest (maximum) limit of quality which could not
be exceeded in fact. During the vegetation period of wheat the different ecological and agrotechnical factors could help or on the contrary
could demage the quality parameters of wheat.
The agrotechnical factors determining the baking quality of wheat can be divided into two groups: the first group means the factors with
direct effects on quality (fertilization, irrigation, harvest); the second group contains the elements with indirect effects on quality (crop
rotation, tillage, planting, crop protection).
Appropriate fertilization could help to manifest the maximum of quality parameters of a wheat genotype and could reduce the qualityfluctuation
in unfavourable ecological and agrotechnical conditions.
We have analyzed the effect of grain maize and sunflower forecrop on three different winter wheat genotype (GK Csillag, Mv Csárdás, Mv Toldi) regarding to the spike number and yield in different fertilization levels in the 2012/2013 cropyear. According to our data after sunflower forecrop we reached higher spike number and yield, which were i...nfluenced by the differences of the varieties. We found significant differences between the varieties in the control treatment. According to our research, GK Csillag has reached the highest yield in the examined fertilization levels and forecrop models too.
The aim of this paper was to provide further information about the nitrogen mineralization processes of soil. A modified incubation technique was applied to establish the amount of easily soluble mineral and organic N forms during the incubation period. An acidic sandy soil was used for incubation, which was sampled from the „Westsik” long-...term field experiment. The incubation was carried out on fifteen selected soil samples which were received different treatments since the experiment was set up.
From the obtained results, the amount of potentially mineralizable N and the mineralization rate constant were determined. Results of chemical analysis and biological interpretation of results are discussed.
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.
Our research work was carried out in the Westsik crop rotation field experiment in 2018. The main research purpose was to analyse the effect of the different organic and chemical fertilizers on parameters of rye. Our results revealed some differences between the different fertilization methods. One spike weight, grain weight of one spike, r...ye plant height, rye plant weight per m2 and 1000 seed weight in crop rotations VII, XV and VIII were different from the data of all crop rotations. This finding can be explained by the fact that crop rotations VII and XV were non-fertilized, only 23.3 t ha-1 straw manure (VII) or green lupine manure was applied as a second crop (XV). In addition, crop rotation VIII consists of four parts where we apply chemical fertilization with green lupine manure as a main and second crop. There is a positive close correlation between rye plant height and other studied characters (rye plant weight per m2, spike length, weight of one spike, grain weight per spike, spike weight per m2, grain weight per m2 and 1000 seed weight).
The year 2013 was rather extreme breeding year because of the uneven distribution of precipitaion and the summer heat. The experiment was set on with eight different genetic characteristics maize hybrids in 2013. In our study were included different kind of breeding season hybrids. We studied the effect of NKP fertilization and row spacing on t...he yield. The fertilizer doses are based on 25-year long-term experiment. Compared to control, the N40+PK treatment has also achieved a significant yield increase, although some hybrid of increasing fertilizer doses yield response to loss. The majority of hybrids reached higher yields using the 50 cm row spacing. The water release of hybrids was measured between 21th August and 17th September weekly, at the same time points. The rainy September slowed ripening hybrids and water release, so the grain wet content at harvest showed higher values.
The 0.01 M CaCl2 universal extractant is known all over Europe since the 90’s. During my research, I exam the phosphorus content determined in 0.01 M CaCl2 of the samples originated from the B 17 National Uniformed Long Term Fertilisation Trials in the experimental site Karcag, in the 40th year of the experime...nt. Relationships between the CaCl2-P and the AL-P content of the soil, the average yields, and the phosphorus balance of the
2006/2007 year were studied. From the results of the study it was concluded as follows:
– Correlation was close (r=0.68-0.7) between the AL-P and CaCl2-P. This is in accordance with the results of previous experiments in Hungary and other countries.
– My studies confirmed that the calcium-chloride method indicates well the deficiency and the surplus of plant available phosphorus. In case of different degrees of negative balance, the amount of CaCl2 extractable phosphorus showed no changes, or decreased, and in case of positive balance it increased exponentially by the long-term effect of P rates.
– The 120 and 180 kg ha-1 rates resulted in significant increases in the amount of CaCl2-P according to the control and treatments that are not fertilized with phosphorus. The 60 kg ha-1 rate didn’t result any increase as it didn’t meet the phosphorus requirement of winter wheat, and presumably the P-balance was negative in the earlier years as well.
– It can be stated that the 0.01 M CaCl2 was able to assess the deficiency and the excess of phosphorus causing negative impacts on environment as well.
We have carried out our outdoor field experiments at the Látókép Experimental Farm of the CAS of the University of Debrecen in the cropyear of 2012/2013 on chernozem soil in a long-term experiment. We have studied the effects of two different preceding crops (sweet corn, sunflower) on the development of the SPAD values of wheat varieties of...different genotypes in the cases of control, N60+PK and N120+PK fertilizer treatments. According to our research results, we have concluded that the preceding crop, the fertilizer application and the variety selection influenced the SPAD values. According to our data, we have measured higher SPAD values after sweet corn preceding crop, the standard deviations were in a smaller range in the case of the studied varieties. After sunflower preceding crop, smaller averages were experienced with wider standard deviation range. In the case of favourable preceding crop, the differences between the varieties are more pronounced than in the case of unfavourable preceding crop. The maximal SPAD values were measured in milky ripening in the case of N120+PK fertilizer treatment.