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Correlation between cultivation methods and quality in some vegetable species
313-317Views:150Quality parameters of 5 table root varieties were tested on 3 sowing dates with different cultivation methods: open field on 15 April and 9 July 2010 and under plastic tents on 19 August. The highest red pigment content (betanin) was measured in the varieties Akela and Mona Lisa (~ 80 mg 100 g-1) of the second (July) crop. This crop is in general use in Hungary. In comparison, in the late sown varieties (August, under plastics) a further pigment increase (10–20 mg 100 g-1) was observed in the same varieties as related to the earlier sowing dates. Yellow pigments (vulgaxanthins) showed similar trends. Roots of the late sowing date (with harvest in December) contained the highest vulgaxanthin values (103.3–124.18 mg kg-1).
Varieties reacted differently to temperature changes during the production period and thus to sugar accumulation. In the second crop (July) higher water soluble solids content was measured on the average of varieties (10.12%) in comparison to the April sowing (7.76%). Beetroots of the spring sowing are recommended for fresh market while the second (July) crop with autumn harvest can satisfy industry requirements. Late sowing under unheated plastic tents supply us with fresh beetroot in late autumn and early winter and prolong the usability of plastic tents.
Six lettuce species/subspecies were tested in the open field and under plastic tents in 3 repetitions for nitrate nitrogen, vitamin-C, polyphenol (gallus acid equivalent – mg GAE 100 g-1) and mineral element (Ca, K, Mg, Na) contents. Our measurements showed lower nitrate nitrogen values under plastic than in the open field (89.10± 8.13 and 127.06±14.29 mg kg-1) on the average of genotypes. Lettuce grown in the field had higher vitamin-C content (1.4 mg%) which is nearly 50% more than in plants under plastic. The highest polyphenol content was found in samples from the field with a conspicuous value of 804.17±56.47 mg GAE 100 g-1 in Piros cikória. Samples grown under plastic were richer in mineral elements (Ca, K, Mg, Na) which can be explained by the higher nutrient content of the soil. In this environment superior Mg content was observed in Edivia (4616.33±
311.21 mg kg-1).Besides the well- known headed lettuce, Piros cikória (Red chicory),the red leaved Lollo Rossa and Tölgylevel (Oak leaf lettuce) should be
mentioned which well deserve further testing in order to supply us with nourishing, healthy food. -
Effects of fermented chicken manure products on the N mineralization rate of the soil using the incubation method
199-204Views:199In our study, the effect of fermented and specially added poultry manure products (superabsorbent polymer (SAP), bentonite and Aegis as a mycorrhizal inoculum) were investigated in a short soil incubation experiment – at 60% water capacity level - on sandy soil. Soil samples were collected from two layers of the incubation pots after the second and fourth week to check the status of the tested products and the processes in the soil. The pH and the electric conductivity (EC) of the samples were measured using an electrochemical method, while the ammonium and nitrate content of the samples was determined with a photometric method. Soil pH and EC values slightly were decreased during the experiment. Our results pointed out that the increasing dose of SAP caused lower soil pH. The nitrate content of the soil did not change significantly during the experiment. It was found that the increasing SAP content in the products, due to its cross-linked structural property, protected the nitrate ions from leaching. Our results suggest that applied SAP does not bind the nutrient ions so tightly in its structure that it competes with the plant for uptake.
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Folic acid content of beetroot leaf and root by different growing stages and genotypes
115-119Views:270An increasing interest has been observed of beetroot leaf as a salad component due to recent studies focusing on their nutritional value. The randomized field experiment was carried out on lowland chernozem soil with 6 varieties, 3 replications and 2 sowing dates. Sampling was performed on 23 of August 2018 at the stage of 30 and 50 days of vegetation, where leaf (30 and 50 days) and root (50 days) were collected. Total dry matter, folic acid and nitrate content were evaluated.
The results of this investigation show that higher total dry matter content was measured in the root (8.47–10.30%) compared to the leaf in both developmental stages (6.47–9.20%). Nevertheless, higher folic acid content was found in the young leaves of 30 and 50 days of development (58.77–113.86 µg 100g-1). Among the examined varieties, Bonel has presented great amount of folic acid not only in the leaves (99.35–113.61 µg 100g-1), but also in the root (89.99 µg 100g-1). Finally, lower nitrate content was found in Libero (316.16 mg kg-1) at 30 days and in Akela (340.41 mg kg-1) at 50 days of development. Thereby, fresh consumption of beetroot leaves are highly recommended.
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Effects of some herbicides on the microbiological characteristics of soil nitrogen cycle under maize plantation
93-100Views:89Nitrogen is a key element for the living organisms and influence not only for the quantity but for the quality of the yield, considerable. Availability of nitrogen from the soil is influenced by several microbiological processes of the Nitrogen-cycle. Among the intensive agricultural production the herbicide application cannot be omitted more information needs therefore about the inhibitor effect of herbicides on the different microorganisms.
An experiment was set up on calcareous chernozem soil under maize culture. Effect of four different herbicides (Acenit, Frontier, Merlin, and Wing) was investigated. The effect of herbicides was measured to four microbiological parameters of the Nitrogencycle (abundance of nitrifying bacteria, nitrate solubilisation, biomass nitrogen and urease enzyme activity). There were singledouble- and five times of recommended doses of herbicides applied for two onsecutive vegetation periods.
From the results of the different doses of herbicides, the following can be stated:
– The Acenit has a stimulating effect on nitrifying bacteria in general. The Frontier and Merlin also influenced the quantity of nitrifyers, however in certain cases decreased in another cases increased the number of bacteria.
– The double doses and five times doses of herbicides was found to be increasing the nitrate content of soil, -especially in 2006.
– The quantity of microbial biomass nitrogen increased in the 60% of treatments and decreased in the 40% of the treatments.
– Except of the result of Wing in 2006 and Merlin in 2005, the effect of simple dose herbicides was the smallest on the urease enzyme activity. According to the results the effect of Merlin was positive; the effect of Wing was negative on the soil enzyme’s activity.
Regarding the application of four different herbicides in three different doses on the microbiological parameters of soil (at two consecutive years-) in 39% of the treatments has resulted a significant inhibitory effect, 28% of the treatments, however have significant stimulating effect on the parameters measured. More than 50% of the inhibitory effect was measured in case of the Wing, at more than 50% of the Frontier the microbiological parameters have not changed. -
Effect of compost/water ratio on some main parameter of compost solutions
117-121Views:271Composting is an efficient technology for the utilisation of by-products and waste. It is also suitable for treating raw materials to convert fertilisers that are not recommended for application without pre-processing. Such is the case with poultry manure, which is very important to pre-treat due to its hazardous properties. An increasingly common form of compost is compost tea, which is made by soaking compost in water. In our experiment, we made compost tea from a composted and granulated poultry manure product. Three mixing ratios were used (1/5, 1/10, 1/10) and compost teas were set for three different extraction times (24–48–72 hours). After elimination of the experiment, the pH, EC, and nitrate and ammonium contents of the samples were measured. The aim of this study was to determine whether there is a difference between each mixing ratio and different extraction times. Based on our results, it can be said that the fluctuation of pH values during the experiment was low. Regardless of the mixing ratio and extraction time, the samples were in the slightly acidic range. The electrical conductivity, nitrate and ammonium content follow a similar trend, the values decrease significantly with the increase of the mixing ratio. Similar tendency was observed at the incubation time. The concentrations of both EC and nitrogen forms increase with increasing incubation time, in most cases significantly.
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Change of soil nitrogen content in a long term fertilization experiment
39-44Views:159The most important aim of sustainable agriculture is to ensure our natural resources – such as soils – protection, which includes fertility preservation and the use of appropriate methods of cultivation.
If we want to get accurate information about the occurred 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 and it is present in the soil mainly in organic form. In general only a low percentage of the total nitrogen content can be used directly by plants in the soil. The mineral nitrogen is incorporate by plants into our bodies. This inorganic nitrogen is produced by the transformation of organic contents through mineralization processes and it gets into the soil by fertilization. This is how nitrogen turnover occurs when mineral forms become organic and organic forms become mineral.
The objective of this publication was to introduce – through some element s of nitrogen turnover- how changing the properties of soil in a long term fertilization experiment.
We established that the fertilization is influenced the soil pH. With the increase of fertilization levels increased the acidity of the soil, maybe it is related with the number of nitrification bacteria. The fertilization and the rotation affected to the quantity of nitrate.
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Effects of spray carrier quality on biological activity of terbuthylazine + mesotrione herbicide combination
110-115Views:115Field experiments were conducted to study affects of pH and hardness of spray water on efficacy of a herbicide combination (terbuthylazine + mesotrione) influenced by several pH adjusters and adjuvants in Debrecen, Hungary in 2008, 2009 and 2010. Favourable or unfavourable effects of pH and hardness of spray water could be observed under field conditions. Evaluation of weed control efficacy is suitable for examination of affects of spray water pH and hardness on herbicides. The terbuthylazine and mesotrione herbicide combination is suitable to control monocotyledonous and dicotyledonous weed species, however, significant effects of hardness and pH of spray carrier was observed only in control of monocotyledonous weeds. Certain pH adjusters (e.g. ammonium nitrate) can lessen harmful affects of water hardness effectively. Significant loss of efficacy of sensitive herbicide was found in hard water (by about 50-60%), and surfactants was not able to eliminate that harmful affect. However, biological activity was the same as in soft water with ammonium nitrate which can overcome the antagonism of salts. That pH adjuster had a more significant affect on the efficacy of the herbicide than the surfactant had in that experiment.
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Changes of some soil chemical and microbiological characteristics in a long-term fertilization experiment in Hungary
253-265Views:330Agricultural 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 doses 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
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The effect of different herbicide on the number and activity of living microorganisms in soil
76-82Views:136Sustainable plant growth, considering the difficulties of weed elimination, cannot be effective without the application of herbicides. However, these chemicals have enormous ecological implications, including effects on the microbiological communities of soils. It is advisable to use herbicides that have minimal secondary effects on the environment and soil-living microorganisms. In contrast, herbicides with prolonged growth stimulating or inhibiting effects are not suitable, because both types have strong influences on the number and activity of bacteria, thus causing changes in the ecological equilibrium.
Preceding small plot experiments, laboratory tests were carried out to study the effect of herbicides used in maize cultures on the number of bacteria and growth of microscopic fungi.
Substances that were observed to have stronger influences were applied in small plot experiments set up in the experimental garden of the Department of Plant Protection of the University of Debrecen. We studied the effects of four herbicides (Acenit A88EC, Frontier 900 EC, Merlin SC and Wing EC) on the microbiological properties of the soil. These herbicides were used in different concentrations in maize culture, and we investigated the effects in different soil layers.
In the laboratory experiments, we determined the total number of bacteria and microscopic fungi and examined the growth of Aspergillus niger, Trichoderma sp. and Fusarium oxysporum on peptone-glucose agar containing herbicides.
During the small plot experiments, soil samples were collected 3 times a year from 2-20 cm depth. The total numbers of bacteria and microscopic fungi were determined by plate dilution method, while the method of most probable number (Pochon method) was used to determine the numbers of nitrifying bacteria and cellulose decomposing bacteria. To evaluate the microbiological activity of the soil samples we measured carbon-dioxide release (after 10 days incubation), nitrate production (after 14 days incubation) and the concentration of C and N in the biomass.
We can summarize our results as follows:
• In laboratory experiments, herbicides caused a decrease in the number of bacteria and inhibited the growth of microscopic fungi.
• Frontier 900 EC and Acenit A 880 EC had the strongest inhibiting effect on microorganisms.
• In small plot experiments, herbicide treatment decreased the total number of bacteria and microscopic fungi.
• Herbicides caused a significant increase in the number of nitrifying and cellulose decomposing bacteria.
• Different herbicides containing the same active compound had similar influences on soil microoorganisms.
• A significant increase was observed in the physiological processes of tolerant microorganisms surviving the effects of herbicides -
Effects of fermented and supplemented chicken manure on the nutrient management aspects of an apple orchard
117-123Views:145AIt is a huge challenge for farmers worldwide to successfully increase the organic matter content of their soils and improve their water balance at the same time. Therefore, the main aim of the study is to develop and test organic-based nutrient composite materials that can be successfully used by farmers to increase soil organic matter content, improve water management parameters and implement water-efficient technologies. The study was performed in the orchard of the Institute of Horticultural Science of the University of Debrecen in Hungary (Debrecen-Pallag). The experiment was set up in a ten-year-old apple (Malus domestica ‘Pinova’) orchard. In the trial, fermented poultry manure and superabsorbent polymers (SAP) were used at different doses to study their effects on soil properties and fruit quality. Applied composite materials increased the nitrate and organic nitrogen content of the soil. Treatments did not affect the sugar content of the fruits but significantly and positively affected the individual fruit weight and the titratable acidity of the fruits.
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The effect of different microbial preparations on some soil characteristics
83-86Views:113In 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 block 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. -
The role and impact of N-Lock (N-stabilizer) to the utilization of N in the main arable crops
51-55Views:236The nitrogen stabilizer called N-Lock can be used primarily with solid and liquid urea, UAN and other liquid nitrogen, slurry and manure. In corn it can be applied incorporated before sowing or with row-cultivator or applied with postemergent timing in tank-mix. In postemergent timing need precipitation for long effect. In oil seed rape and autumn cereals the N-Lock should be applied with liquid nitrogen in tank mix late winter or early spring (February-March). The dose rate is 2.5 l/ha. N-Lock increases the yield of maize, winter oil seed rape, winter wheat and winter barley 5-20 %. The yield increasing can be given the thousand grain weight. In case of high doses of nitrogen it can be observed higher yield. The quality parameter also improved, especially the oil content of winter oil seed rape and protein and gluten contents of winter wheat. The use of N-Lock increases the nitrogen retention of soil and reduces nitrate leaching towards the groundwater and the greenhouse effect gas emissions into the atmosphere. The degradation of the applied nitrogen is slowing down and the plant can uptake more nitrogen in long period. The effect of N-Lock the nitrogen is located in the upper soil layer of 0-30 cm and increasing the ammonium nitrogen form. The product can be mixed with herbicide products in main arable crops.
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Examination the effects of different herbicides on the soil microorganisms of a calcareous chernozem
121-126Views:91Pesticides play a key role in fighting weeds, pests and parasitic fungi. According to surveys, pests reduce the yield of agricultural crops by 35% worldwide. Pests, fungi and weeds account for 14%, 12% and 9% yield loss, respectively (Gáborjányi et al., 1995). Chemicals have contributed to increasing and maintaining the yields of crop production for decades. Today, agricultural production (in spite of many efforts) is unthinkable without the use of pesticides (herbicides, insecticides and fungicides). On the other hand, these chemicals contribute to the pollution of the atmosphere, surface and underground waters, and agricultural soils, especially if they are applied improperly.
The sustainable agricultural production pays attention to environment-friendly cultivation-technologies; but at the same time it makes an effort to produce good quality and economical products. The examination of the herbicides’ secondary effects, fits into this chain of idas namely, how the herbicides affect – stimulating or inhibiting – the soil microbiological processes, prevention of soil fertility.
In the course of the experimental work the effect of herbicides on soil biological properties were examined in different maize (Zea mays) cultures. We wanted wished to know that how the herbicides affect the quantity change of soil microorganisms, the life of different physiological groups of bacteria and the activity of microorganisms. A small pot experiment was set up in 2008 with the application of two herbicides - Acenit A 880 EC and Merlin 480 SC – in the breeding house of the Department. The moisture content and nutrient supply were at optimal level in the experiment.
On the basis of results the following can be stated:
1. It can be stated that the two herbicides and all their doses affected negatively the number of total soil bacteria, the
inhibiting effects were significant. The quantity of microscopical fungi increased by the effect of Merlin 480 SC and decreased in the treatments of Acenit A 880 EC.
2. The Acenit A 880 EC had stimulating effect on the nitrate mobilization. The CO2-production was stimulated by the basic doses of herbicides; the other treatments did not influence the CO2-production significantly.
3. The quantity of microbial biomass-carbon –except for only one treatment- decreased significantly by the effect of herbicides. Besides it, the quantity of microbial biomass-nitrogen increased significantly in the treatments of Acenit A 880 EC.
4. The biomass of test plant decreased in the treatments of herbicides, their quantities were smaller than in the control. In the pots treated by Merlin 480 SC, parallel with the increase of doses decreased the quantity of plant-biomass. -
Examination of the chlorophyll content of maize hybrids of different maturity groups at different N fertiliser doses
159-162Views:131Nitrogen fertilisation is a critical point of maize production. Five hybrids of different maturity dates were examined in a field experiment, three treatments (different application dates) and three basic fertiliser doses (0, 60, 120 kg ha-1 N) were used. At the 6-leaf-stage of maize, each fertilisation level of the 2nd and 3rd treatment was given 30 kg N ha-1 fertiliser active ingredient in addition to the basic fertiliser doses with the exception of the control plots and further 30 kg N ha-1 fertiliser was applied at the 12-leaf-stage. The final fertiliser doses were 0, 90 and 150 kg N ha-1 in the second treatment and 0, 120 and 180 kg N ha-1 in the 3rd treatment. The whole amount of the basic fertiliser (ammonium nitrate) was applied in the spring, one month before sowing.
The relative chlorophyll content of the maize leaves was measured, with a Minolta SPAD-502 measurement device. The measurements were carried out at the 6-leaf growth stage (V6) of maize on the youngest fully developed leaf of the 6th, 7th and 8th plants from the second row of each plot.
There were significant differences in the SPAD-readings measured at the V6 phenophase of maize between the hybrids (p<0.001) and the fertiliser treatments (p<0.05). The regression analysis did not show any correlation between the SPAD-values and fertilisation.
The highest significant SPAD-reading and yield were obtained by applying 120 kg ha-1 N. As a result of the regression analysis performed on yield, it can be concluded that the correlation between fertilisation and yield in the 1st and 2nd treatment was moderately close (r=0.439, r=0.480) and it was close in the 3rd treatment (r=0.513). The correlation between the SPAD-readings and yield was the closes in the 2nd treatment (r=0.639), while the SPAD-value had a 40.9% influence on yield (p<0.001).
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Studies of the effects of N fertilizers and Microbion UNC biofertilizer on microelement content of horseradish (Armoracia macrocarpa)
41-45Views:131A 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. -
Studies of the influences of different N fertilizers and Microbion UNC bacterial fertilizer on the nutrient content of soil
134-140Views:107A field experiment was conducted to examine the effects of different nitrogen fertilizers in combination with bacterial fertilizer on
nutrient uptake of horseradish and plant available nutrients of the soil. Three different N fertilizers, ammonium-nitrate, urea and calciumnitrate
(116 kg ha-1 N) in combination with Microbion UNC bacterial fertilizer (2 kg ha-1) were applied as treatments in a randomized
complete block design in three replications. In this paper we presented the results of soil measurements. The soil of the experimental area
was chernozem with medium sufficiency level of N and P and poor level of K.
Our main results:
The amount of 0.01M CaCl2 soluble inorganic nitrogen fractions, NO3
--N and NH4
+-N and also the quantity of soluble organic-N were
almost the same in the soil. N fertilizers significantly increased all the soluble N fractions. The amount of NO3
--N increased to the greatest
extent and the increase of organic N was the slightest. We measured the largest CaCl2 soluble NO3
- -N and total-N contents in the plots
treated with ammonium-nitrate, the largest NH4
+-N in the plots treated with calcium-nitrate and the largest organic-N fraction in plots
treated with urea.
Bacterial inoculation also increased both soluble inorganic nitrogen forms and also total-N content of soil compared to the control. In
the case of combined (artificial and bacterial fertilizer) treatments we measured lower NO3
--N, organic-N and total-N compared to the
values of plots having only nitrogen fertilizer treatments. On the contrary in the plots with combined treatments the CaCl2 soluble NH4
+-N
content of soil in more cases were higher than that of values with artificial fertilizer treatment.
As a function of calcium-nitrate application increased AL-P2O5 and AL-K2O values were measured compared to control. Microbion
UNC supplement of calcium nitrate yielded also increase in AL-P2O5 and AL-K2O values, till then supplement of ammonium-nitrate fertilizer
yielded a decrease in these values compared to the control.
All nitrogen fertilizers resulted in a significant decrease in AL-Mg content of soil compared to the control. Nevertheless bacterial
fertilizer increased AL-Mg values in any cases. -
Practical experiences of a designing and operating a pilot aquaponic system
27-32Views:335Aquaponics is the combination of fish farming (aquaculture) and the soilless cultivation of plants (hydroponics). The aquaponics system is an artificial, recirculating ecosystem, in which bacterial processes convert the waste materials in the water used for fish rearing into plant nutrients, and therefore with the generated heat it is suitable for culturing economically valuable plants, and thus it mitigates the nutrient laden and quantity of the intensive fish producing systems’ effluent water.
The primary goal of our 12 separate unit’s aquaponics system was to gain experience. We would like to find the right plant species, which are fit for that medium, and their crop can be sold. Besides the plants, our attention focused on the fish. Two fish species were included in the experiments, the common carp and barramundi. It was difficult to create them a perfect living space, besides a constantly changing conditions temperature. Apart the above mentioned we had a problem with the number of individuals per tank, the deformity of the fish body and the too high volume of pH (we registered continuous values above 8.4). We get by carps 4.7 grams of weight gain during 15 weeks, because of the bad conditions.
The main problems at the plants are caused by aphesis and protection against sunburn. Even so we have got the multiples of field yields for each plant species. At salad has grown twice of field yields, tomatoes one and half, kohlrabi than 3.5 times more. The causes of multiple yields are the continuous balanced water and the nutrient uptake of plants. Each plant species fit for cultivating in aquaponics and their crops are delicious, chemical -free, safe and marketable. The plants should be more concentrated. After the experiment, it has been determinated that the carp is suitable for aquaponics, but greater weight gain could be achieved with optimal selection of size of rearing units.
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Impact of ammonium nitrate and Microbion UNC bacterial fertilizer on dry matter accumulation of ryegrass (Lolium perenne L.)
35-39Views:101Pot experiment was performed to investigate the effects of increasing NH4NO3 doses with or without Microbion UNC bacterial fertilizer
application on dry matter production of ryegrass (Lolium perenne L.). Experiment was set up on calcareous chernozem soil of Debrecen-Látókép and on humus sandy soil of Őrbottyán. The bi-factorial trials were arranged in a randomized complete block design with four replications. Grass was cut three times. Dry matter production was determined and the sum of biomass of cuts was calculated as cumulated dry weights. Analysis of variance was carried out on the data in order to provide a statistical comparison between the treatment means. The least significant difference (LSD5%) test was used to detect differences between means. On the basis of our results it can be concluded, that the dry weights of ryegrass cultivated on chernozem soil were higher than on sandy soil. With increasing nitrogen supply the dry matter production of grass significantly increased in both types of soils. In case of sandy soil the increasing effect was more expressed, but dry weights of this soil never reached the appropriate values of chernozem soil. Application of Microbion UNC had positive effect on dry matter production of ryegrass grown on both two types of soils but the effect was more expressed on chernozem soil. Finally it can be concluded that the increasing effect of NH4NO3 on biomass weights was more expressed in both types of soils, the biofertilizer application also increased the dry weights of plant in a small degree. -
Measuring of nitrogen leaching using ceramic suction cups at different locations
10-17Views:89Ceramic suction cups were used for the measurement of N-concentration in soil solutions under different soil and climate conditions in both field experiments of Rostock University and Agricultural University of Debrecen (Hungary). Depending on the soil utilisation the change in the N concentration of the soil solution can be proved on both sites.
The experimental field of Rostock University can be characterised by its high groundwater table. The nitrogen concentration of soil solutions in the different soil layers were determined by the trend downward of water. In the dactylis (Dactilis glomerata) experiment, the quadruple treatments involved the following: with and without N-fertiliser, with and without harvesting, respectively. In the lower soil layers, the least rising N concentrations were established in case of the treatment without N-fertiliser combined with harvesting. The nitrogen leaching calculated from the infiltrated water quantity and the nitrate N concentration increased in the following order: without N-fertiliser, with harvesting < without N-fertiliser, without harvesting < with N-fertiliser, with harvesting << with N-fertiliser, without harvesting.
The field experiment site of Debrecen can be characterised by a low groundwater table. The effect of N-fertilisation on the nitrate-N concentration of soil solution in the soil layers can be stated unanimously. Permanent nitrate-N leaching cannot be established due to the water upward movement under semiarid climate conditions. Intermittently transfer of nitrate-N between the soil layers is probable in cases of remarkable precipitation.