Comparision of growth of mature all-female and mixed-sex Common carp (Cyprinus carpio L.) stocks in RAS

The common carp (Cyprinus carpio L.) is the most important fish species in Hungary, it is more than 70% of the total Hungarian fish production. The common carp production is important not only just in Hungary but in Middle-East Europe, as well as Southeast Asia. Majority of the production comes from fishpond culture. If the production sector wants to meet the increasing customer demands, there is need to intensify research on the intensive fish production opportunities for example all-female common carp technologies. The all-female technology is one of a genom-manipulation technology. Its production showed better growth rate than mixed-sex population in pond culture. Our experiment combined the recirculation aquaculture system (RAS) and the all-female common carp stocks intensification technologies. The reason for the experiment, is that there are no result about the growth of all-female common carp growth in RAS.

The experiment used the „Tatai grey scale type” common carp stocks. We propagated two all-female stocks (T2 and T3) and a control group (TK). Due to technological characteristics of RAS, the water quality parameters were the same for all treatments and corresponded to the technological tolerance of common carp.

The experimental period was from July 10, 2019 – November 20, 2019. Result of growth performance showed that the growth of mixed-sex stock was significantly higher than all-female stocks; (Control=3692.0±590.5g, T2=3438.8±415.4g, T3=3294.1±659.1g). Feed conversation ratio (Control=1.3±0.1 T2=1.5±0.2 T3=1.6±0.5) and SGR% (Control=0.8±0.0 T2=0.7±0.1 T3=0.7±0.1) were similar.

By the results it can be said the all-female common carp technology has neither advantages nor disadvantages compared to the mixed-sex stock. The all-female technology can be beneficial if the consumers need female common carps. It is worth continuing the experiment and examine how the stocks will perform above 3kg body weight.

Ecological Conditions of Agricultural Land Use in Transcarpathia

The unbalanced anthropogenic effects for several decades resulted in significant technogen damages in the ecosystem of Ukraine. Excessive land development, including the use of slopes, effected the disintegration of the natural balance of lands – arable-lands, meadows, forests, and watershed areas – producing quite a negative effect on the landscape’s nature itself. It has to be stressed that according to other indexes, too, agricultural lands show a tendentious deterioration.
Erosion, caused by water and wind, is one of the most influential factors in the degradation of agricultural soils and in the reduction of the productiveness of benefital lands. Nowadays the degree erosion became significant and it directly endangers the existence of the soil which is a principal chain-link of the agricultural cultivation as well as an irreplaceable element of the biosphere.
The social and political changes in Ukraine’s life demand fundamental modernization in the land utilization both in ecological and in economical aspects. However, these aims can be realized only if, during the developments, we base on the up-to-date results of agronomics, and we do further research in the relations of agricultural land use and environmental protection. According to the latest theories, rational and environmental-safe agricultural production relates to the optimum correlation of the natural- and agricultural- ecosystems as well as to the reconstruction of agricultural areas built on the basis of environmental protection.

Effect of the crop-year on plant protection feature of sunflower

Our study focused on plant density reactions of sunflower hybrids on chernozem soil in years with different levels of available water (2011 and 2012). We studied factors (i.e.infections, yield) that are most affected by the amount of precipitation.

However the amount of precipitation varied in 2011 (average amount of precipitation) and 2012 (drought), Sclerotinia and Diaporthe infections were significant in both years. Diaporthe was stronger in 2011 while in 2012 Sclerotinia infections were greater than average. Higher plant density provided for a favorable microclimate for pathogens meaning that increased stock density enabled enhanced infections. Maximum levels of infections in both the cases of Diaporthe and Sclerotinia were measured at a plant density level of 65 000 plants ha-1.

2012 yields (control: between 2 289 and 3 261 kg ha-1, two-time treated: between 2 699 and 3 659 kg ha-1) were significantly lower compared to the results of 2011 (control: between 2 825 and 3 672 kg ha-1, two-time treated: between 3 059 and 4 059 kg ha-1). Fungicide treatments led to an increased yield in both years: 9.5% in 2011 and a notable, 15.1% growth in 2012. We applied regression analysis to calculate optimum plant density for the examined years and treatments. Based on the calculations we found that in the cases of both treatments optimum plant density was 53 000 plants ha-1, while in 2012 the optimum was higher due to lower level of infections: 56 000 plants ha-1 in the control stock and 64 000 plants ha-1 in the stock treated twice.

The Effect of Forecrop and Plant Protection on the Pathology Parameters and Yields of Winter Wheat

We carried out our experiment in the cropyears of 2000/2001, 2001/2002 and 2002/2003, on calcareous chernozem soil, at the experimental site of the Debrecen University Farm and Regional Research Institute, at Látókép. We examined the disease resistance and the yield quantity of Mv Magvas variety by adopting different forecrops and plant protection technologies, at 30+30 N level and at normal cereal row spacing. We applied two forecrops (wheat and pea) and two plant protection technologies (extensive and intensive). We measured the rate of infection by population survey in the first ten days of June.
In the course of our examinations, we found, that the rate of powdery mildew infection was higher in the thicker population sown after pea forecrop in all three years, as powdery mildew is not a typical cereal disease.
The infection rate of leaf mildew and DTR (Dreschlera tritici-repentis) was higher after wheat forecrop in all examined years, because these are typical wheat diseases and infection centres in the soil promote the spreading of these diseases. However, it was possible to parry the adverse effect of forecrops by intensive plant protection.
Due to the chernozem soil, wich has good water management features, and due to the good preparation of the seedbed, the effect of forecrops on yield quantity did not appear in the examined years. The quantity of the yield was only slightly larger after pea forecrop in the cropyears of 2000/2001 and 2002/2003 than after wheat. Nonetheless, the data of technical literatures state that the yield quantity can be larger, even by 15-20%, after pea forecrop.
In the course of intensive plant protection technology, we applied systemic pesticides, while in the course of environmentally sound technology, we used contact pesticides of sulphur content. In those populations that were treated with environmentally sound plant protection technology, infection rate was higher in all three years.
Yield quantities were somewhat lower in the course of applying extensive, environmentally sound technology, because diseases appeared in these populations to the higher degree. Powdery mildew does not, but leaf mildew and Dreschlera tritici-repentis have a significant yield decreasing effect. With appropriate, well-selected fungicides, we were able to keep every leaf diseases well in hand, and the rate of infection was almost independent of the influence of the breeding year.

Pre-treatment of wastes containing keratin in industrial conditions

The aim of the research was a development of a featherdegradation technology in industrial circumstances. During the experiments we determined the parameters of the critical environmental and technological limitation factors. Because of the high keratin-content the degradation (and composting) of the feather is difficult. With the developed technology huge mass of feather can be used fast and easily in biogas production and in the adjustment of the optimal element ratio of biomass. The industrial experiments were implemented in a 6m3 heatable double-walled
tank with stirring-shovels and aeration-system. The degradation process was followed with extinction measurements.
According to the experiments that were done the best results were given at the case which was heat-treated at 70°C, was injected with 1% bacteria concentration, and where 1:3 feather:water ratio was set if we consider the effectiveness of degradation and the hydraulical retention time.

The significance of local meteorological stations in research planning

The goal of research planning is to optimize human and material resources while maximizing efficiency. If there are databases that can be used as a substitute for own data collection, effective research can be facilitated by reallocating resources. In the case of environmental studies, the knowledge of the climatic conditions of the study period is known to be a key factor in research planning process.

 In the present study, the data of our meteorological station in our research area (known as “Szamárháti Tanya”, Kesznyéten, Hungary) was compared with the measurements of meteorological stations operated by the competent water authority. Stations were taken into the study within a 10 and 20 km radius over a period of 21 months, to determine which provided more relevant data from the area.

During the evaluation of results, the relationship between the local and regional weather stations were determined, and deductions were made from the obtained results to support the decision which of the targeted investigations could be of greater benefit. 

New Possibilities of Brown Bullhead (Ictalurus nebulosus) Farming

The brown bullhead (Ictalurus nebulosus) has been settled in Europe at the end of Century XIX from North America. In Hungary it has been brought in 1902. The naturalization of this species was successful because the brown bullhead found adequate conditions for its life and reproduction in Hungary. But it was unsuccessful because lost its excellent growth.
In inland water habitats-and that’s why also fishponds-extraordinarily multiplied, but because of its slight growth this species is undesirable for the native farmers. The brown bullhead is concurrent for domestic fish species, on the other hand its weight not more than 150-200 g. Occasionally it was exterminated, but multiplied again and again.
In 1999 we placed out black bullhead offspring in a pool of a new intensive fish farm, in order to breed at least 300-350 g weight for the customers. The accidental trial was surprisingly successful. Consequently, the black bullhead prefers the artificial food, and produces excellent growth parameters and specific feed-live weight conversation ratio.
On the 20th of September 1999 there was placed 23 300 pieces of brown bullhead offspring, with 28 g average weight and 625 kg gross weight. When we sold them on the 22nd of February 2000, the gross weight was 3387 and the live weight gain was 2735 kg. The gross weight of the feed was 3041,8 kg, and the feed-live weight conversation ratio was 1,11 kg/kg.
Because of this successful trial the managers of the farm wanted to start systematic experiments to work out the details of the intensive farming of brown bullhead. We undertook to help to find the right place of the species in the Hungarian fish processing because of the increasing native and foreign demand.

Rural Entertainment in the Püspökladány sub-region

The Püspökladány statistical sub-region is geographically located in Hajdú-Bihar county’s south-west corner, in the area called Nagy-Sárrét. The tourism of the sub-region has been highly determined by the proximity of Hortobágy National Park and the presence of thermal water, one of the most important resources of the region. As Hajdú-Bihar county – especially Debrecen, Hajdúszoboszló and Hortobágy – possesses these attractive factors as well, in the Püspökladány sub-region rural tourism could be an important means of catching the interests of – mostly Hungarian – tourists.
In the course of this research, my objectives were to introduce the rural hosts of the sub-region, the main features and problems of rural hospitality as an enterprise and the characteristics and activities of rural tourist – from the view of the hosts.
I chose questionnaires as the method of the investigation, and evaluated them with the help of SPSS and Microsoft Excel software. During the evaluation, I calculated distribution, arithmetic mean, deviation and carried out significance-analysis.
The investigations confirmed my presumption, i.e. rural tourism has not gained ground yet in the Püspökladány sub-region. This statement is proved by the fact that I completed only 8 questionnaires in a sub-region with 13 settlements, where rural host activity concentrates on 3 settlements. The results of the questionnaire-evaluation prove the aforesaid.

Comparative study of a winter wheat variety and hybrid sown after different pre-crops on chernozem soil

Wheat production is a determining branch within Hungarian crop production (produced on nearly one million hectares). Weather anomalies caused by climatic change confirmed the importance of the biological background (variety, hybrid) in wheat production. The adapting ability and reaction of different wheat genotypes towards nutrient supply were studied in a long-term field experiment on chernozem soil type in the case of different pre-crops (sunflower and maize). According to the experimental results of the vegetation of 2017/2018, the yield of the variety Ingenio sown after the sunflower as previous crop ranged between 4168 and 8734 kg ha-1, while in the case of maize as previous crop, this value ranged between 2084 and 7782kg ha-1, depending on the applied nutrient supply level. The studied genotypes produced rather significant yield surplus as a response to the application of mineral fertilization (4.6–5.1 t ha-1 after sunflower and 5.7–6.3 t ha-1 after maize). Optimal mineral fertilizer dosage was determined by both the genotype and the pre-crop. N-optimum values of wheat genotypes was determined using regression analysis. In the case of the variety Ingenio sown after sunflower, the optimum range was N144-150+PK, while after maize, it was
N123-150+PK, respectively. For the hybrid Hyland, these optimum ranges were N114-120+PK, just as N150-153+PK, resp. The application of optimal mineral fertilizer dosages improved water utilization of the studied wheat genotypes to a significant extent. WUE values of the control, unfertilized treatments ranged between 4.1–8.3 kg mm-1, while in optimal fertilizer treatment, it ranged between 15.5 and 17.4 kg mm-1.

The change of the inner content parameters of table beet (Beta vulgaris L. ssp. esculenta Gurke var. rubra L.) as a result of storage

The stored vegetables play a key role in the vegetable consumption. After harvesting, the storage conditions greatly affect nutritional parameters of the crop. The red beet is a root vegetable, which is manufactured mainly fresh in our county, therefore we do not have enough information about the storage. In our experiment, 5 varieties (Rubin, Akela, Larka, Libero, Mona Lisa) were examined in prismatic structure (0–5 °C and 95–97% RH) through 5 mounths.

Our measurements proved that under the appropriate storage conditions water loss was also occurs, which increased the dry matter content (average of 0.5 g 100 g-1). The bioactive compounds, like pigments (betanine and vulgaxanthin) and the quantity of flavonoids, were significantly increased during the experiment.

The results showed that the nutritional parameters of the 5 types was positive during the prismatic structure. However, this storage method negatively affected the bioactive compounds of the Akela genotype. Further studies are recommended for proper storage parameter adjustment, which is justified by the need of the different varieties. The optimal conditions enable us to preserve and to increase the best nutritional index.

The Presentation of Debrecen University’s Solar Energy Power Plant

Energy plays an important role in everyday life and in the economy. The use of fossil energy sources greatly damages the environment. Besides this, the quantity of these energy sources is limited. Therefore, it is important to increase the share of renewable energy sources (solar, wind, water, biomass) in energy generation. Huge amounts of energy (1150-1300 kWh/m2) arrive at the earth from the sun, which utilized in passive and active ways. One of the active applications is photovoltaic current production, in the course of which electricity is produced directly with PV-Panels. This can be fed into the grid.

The action of bed-slope the fish community’s composition of the watercorses on the Zagyva-Tarna watersystem

Between 2003 and 2005 faunistic survey was completed in the sections of the low- and highland watercourses of the water-regime of the Zagyva and Tarna rivers. On the basis of bed-slope, dominance and frequency of the fish species the following sections can be divided in the examined streams:
1./ Upper-chub-zone: the bed-slope is above 15 m/km. The typical species of this zone – the frequency of these is more then 50%, the dominance is more than 5% – is the Barbatula barbatula, but in the case of bigger streams Leuciscus cephalus is also characteristic.
2./ Middle-chub-zone: the bed-slope is between 5-15 m/km. The typical fishspecies–besides the Barbatula barbatula and Leuciscus cephalus – is the Gobio gobio.
3./ Down-chub-zone: in the case of larger watercourses (Zagyva and Tarna rivers) the bed-slope is 1,2-5 m/km, at smaller streamlets it is 1,7-5m/km. The typical fishspecies–besides the 3 above mentioned species–are the Cobitis elongatoides, the Alburnus alburnus and in the watersystem of Tarna the Alburnoides bipunctatus.
4./ Top-perch-zone: the bed-slope is 0,3-1,2 m/km, or at smaller streamlets it is 0,3-1,7 m/km. The typical fishspecies–besidestheCobitis elongatoides, the Alburnus alburnus and the Alburnoides bipunctatus - are the Rutilus rutilus, the Gobio albipinnatus ant the Rhodeus sericeus.

The effect of different fat content fish feed on the production parameters and meat quality of the hybrid striped bass

The interspecific ’hybrid striped bass’ is the result of cross breeding. Their offspring have got good chances of growth and tolerate extreme water temperatures and the content of dissolute oxygen more than their parents. Furthermore, they are more resistant to diseases. Therefore, the hybrid is perfectly suitable for intensive fishery production.

Our experiment lasted for seven weeks. We analysed the indices of growth and production of the hybrid as the consequence of nurturing them with two feeds of high nutritive value during this period. We examined the content of fat and of fatty acids in the flesh of these fish. There were no considerable differences in terms of weight gain, feed conversion ratio and uneven growth between the two groups, while survival was less likely among the the fish which had consumed more fat. We demonstrated, examining the flesh of the individuals which had consumed feed containing lower fat content, that it was fattier and contained more dry matter than those that had been fed of higher fat content. Besides, the content of omega-3 and omega-6 fatty acids was higher in the fish that had consumed less lipids.

Amelioration and arable land-use possibilities of Solonetz soils in the Trans-Tisza region of Hungary

Salt affected soils cover about 1 million hectares in Hungary. This paper is based on the research results obtained at the Karcag-puszta long-term experimental site, where, depending on the catena, crusty (A horizon=0–7 cm), medium (A hor.=8– 20 cm) and deep (A hor.>20 cm) subtypes of the Meadow Solonetz soil could be found. The chemical reclamation was made specifically for the given site. Lime was applied on the soils with neutral or slightly acidic top layer, while on the soils with alkaline top layer, gypsum was applied. As regards internal drainage, a tube system with an average depth of 1 m and 5, 10 and 15 m drain spacing was constructed. Decreasing salt and sodium content could be measured both in drained and non-drained soils. The advantage of drainage was that the leachingout extended to the whole layer above the drain pipes, while without drainage, the Na ions exchanged from the upper layers still accumulated at a depth of 60– 100 cm. In the first two decades, the groundwater level was deeper and leaching was the dominant process. Since 2004, due to the frequently high groundwater level, the leaching and deepening of the fertile top layer has been slower.

Changes in the Quality Parameters of Wheat Samples of 16% Moisture Content during Storage

We have carried out storage experiments with wheat varieties Magvas, Fatima, Mv Emma and Mv Pálma from the 2001 growth year. During the first half of the experiments quality parameters, such as changes in moisture, protein and gluten contents as well as pharinograph readings, falling numbers and sedimentation indices were analysed and tested at an average initial moisture content of 13%.
The findings in the changes in the quality parameters of different wheat varieties with 13% moisture content as a function of storage time duration were published in an earlier paper of mine (12/04/2002).
This paper wishes to give an account of the second part of the storage test when the moisture contents of the different varieties were raised to 16% and the changes in the quality parameters were monitored for seven weeks. The findings show that contrary to what had been experienced in the first half of the trial, there were no changes in the protein contents, pharinograph readings, water uptake or Zeleny counts and falling numbers showed decreases with each of the varieties tested.

Comparative analysis of soil analysing datas on different sempling-plots

Hibrid maize is cultivated on larger plots, therefore the sown areas of hibrid maize are heterogeneous from a pedology aspect. Heterogenity causes problems during tasseling, chemical plant protection and harvest. The heterogenity of sown areas can be compensated by fertilization which is based on soil analysis. We carried out research into change of the soil on four soil types from 1987 to 2005.
There were no significant changes in pH, hydroiodic acidity, CaCO3-content, humus-content on meadow chernozem soil. We detected equalization of salin content in the examined soil layers. There were no significant changes in the measured values on chernozem meadow soil and solonetz meadow soil in 2005. We discoverd equalization of saline content on chernozem meadow soil, but the changes were not as obvious as the changes on meadow chernozem soil. We found salinization in the 30-60 cm soil layer on type meadow soil that may be due to water movement.

Microbiological preparations affecting the soil nutrient availability and growth of ryegrass in a pot experiment

The effects of different bacterial fertilizers and their combinations with NPK fertilizer and wheat straw were investigated on some soil properties (chemical parameters) and on the biomass production of testplant. The applied quantities of the bacterial fertilizers were the double of the recommended dose. The experiment was set up in 2013 at the Institute of Agricultural Chemistry and Soil Science, in a three replications, in a random block design. Calcareous chernozem soil; originating from Debrecen (Látókép) was used with ryegrass (Lolium perenne L.) test plant. At the end of the experiment (after 8 week) the samples of soil and plants were determined for nitrate-nitrogen, ALsoluble phosphorus and potassium content of soil, the weight of green biomass of ryegrass per pot, the dry matter and moisture content of ryegrass. Straw treatment resulted better water and available nutrient content of soil in general. Inoculation however was not improving the biomass production over the fertilizer treatment. Interrelation with the recommended dose could be further studied.

Microbiological quality of bulk tank raw milk from two dairy farms in Hajdú-Bihar County, Hungary

Two main channels have been identified to be responsible for microbiological contamination of raw milk and milk products. Firstly, contamination has occurred due to udder infection from the cow or the blood which harbours most bacteria that come in contact with the raw milk. Secondly, via external factors (may include faeces, skin, contaminated water, environment etc.) which are associated with the operation of milking. There is direct contact with the milk and/or surfaces before, during or after the milking, posing public health risk and economic decline. The aim of this study was to examine the bacteriological quality of bulk tank raw milk samples collected from two different size dairy farms (Farm 1 and Farm 2) of different housing forms (cubicle loose and deep litter) in Hajdú-Bihar County, Hungary in July, 2017. Three samples were taken from each farm, and the total plate count, coliform count, Escherichia coli count, Staphylococcus aureus count, and yeast and mould count were determined in them.

The results clearly showed low level of all measured bacteria group load in Farm 1 samples in comparison to Farm 2 with the exception of coagulase-negative Staphylococcus (CNS) which represented high level in general, indicating significant difference (P<0.05). The mean value of total plate count in Farm 2 samples was higher (1.0 × 105 CFU/mL) than Farm 1 samples (2.8 × 104 CFU/mL). There was a significant difference (P<0.05) in mean count of coliforms in raw milk samples between Farm 1 and Farm 2. Similarly, results of E. coli were significantly different (P<0.05) with mean count of 1.44 × 102 CFU/mL and 2.02 × 103 CFU/mL for Farm 1 and Farm 2 respectively.

Results of Staphylococcus aureus also showed significant difference (P<0.05) with mean count of 9.7 × 101 CFU/mL for Farm 1 and 6.28 × 102 CFU/mL for Farm 2. The mean of mould count recorded was 1.07 × 102 CFU/mL and 4.93 × 102 CFU/mL for Farm 1 and Farm 2 respectively. The recorded mean of yeast count was 1.68 × 103 CFU/mL and 3.41 × 103 CFU/mL for Farm 1 and Farm 2 respectively; however, both farms showed no significant difference (P>0.05) in terms of mean of mould and yeast count. Although Farm 2 produced six times lower milk quantity than Farm 1, the measured microbial parameters were high. Both farms’ microbiological numbers were higher above the permitted limit values as stated by Regulation (EC) No 853/2004, Hungarian Ministry of Health (MoH) 4/1998 (XI. 11.).

This could be an indication of non-conformance to effective GMP, ineffective pre–milking disinfection or udder preparation, poor handling and storage practice, time and temperature abuse and inadequate Food Safety Management System Implementation. Therefore, our recommendation is as follows; establish control measures for pre- and postharvest activities involved in the milking process which would be an effective approach to reduce contamination of the raw milk by pathogenic microorganisms from these farms, strict sanitation regime and hygiene protocol be employed and applied to cows, all equipment, contact surfaces and minimize handling of the milk prior, during and after milking. This will also serve as scientific information to the producers for continual improvement in their operations.

The effect of water supply and crop year on the yield potential of sweet maize (Zea mays L. convar. saccharata Koern.) hybrids with different genotypes

The successfulness of crop production is significantly affected by not only the the average yields that provide cost effectiveness, but also the success of striving for yield safety, therefore, varieties and hybrids tolerant to environmental stress factors are worth being included into the sowing structure. Our aim was to further the decision making of producers in prepaering the right sowing structure by the evaluation of sweet maize hybrids’ tolerance to excess rainfall.
We performed our examinations in an extremely wet year (2010) on chernozem soil on three sweet maize hybrids (GSS 8529, GSS 1477, Overland) in 12 replications. Comparing the yields of 2010 with those that can be expected under optimal rainfall conditions, we showed that the examined hybrids react to the amount of rainfall higher than their needs with yield depression. The excess rainfall tolerance of the examined hybrids is different in the case of each hybrid.

Environmental Consequences of Efficient Use of Nitrogen Fertilizers

Nitrogen fertilizer represents major economic burden. For this reason, although the efficiency of nitrogen utilization varies highly, its actual use generally remains at low levels; these averaging between 25 and 50%. We set up an experiment at the Oradea Research Station, using 15N labeled fertilizers, in order to investigate the possibility of increasing N fertilizer efficiency in winter wheat under irrigation conditions.
Fertilizers labeled with 15N allows us to individually determine its effect on yield formation, as well as the use efficiency of N from fertilizer following application rate and time. The amount of N derived from fertilizer as determined in straw and grain yield is high. When the labeled fertilizer is applied at tillering time, the values of this indicator rise when higher N levels we applied.
In separate experiments, we investigated a series of aspects connected to chemical fertilizer regarding the determination of the type of fertilizer, optimum time and rates of application; all these as a function of the special pedoclimatic conditions.
The results obtained in the field show that the effectiveness of N utilization in wheat is most variable and generally low, often ranging between 25 and 33%, owing to N loss within the system through leaching and NH3 volatilization.
A readily achievable increase in efficiency of 5 percentage points would result in considerable savings, and can be brought about by reducing nitrogen losses. The added benefits to the environment in terms of reduced ground/water contamination and lowered nitrous oxide (N20) emissions would also be substantial.
The figures for N fertilizer use efficiency (% N range from 35.5 to 72.6, the highest value being recorded with an N application of 120 kg/ha at tillering, when the previous crop was sunflower).

Allelopathic Effect of Italian Cocklebur on Sugar Beet

Cockleburs are noxious weeds in Hungary, where they are widespread in row crops, especially in maize, sunflower and sugarbeet. A low density population of these weeds may be harmful because of their large competitive ability, fast growth in early phenological stages, allelopathy, and persistant sprouting.
Allelopathy of Xanthium italicum Mor. was examined during the growing season in 2004. Root and shoot samples were collected at 4 or 5 leaves stage (in the end of May and in the beginning of June) and before flowering (in the beginning of July) before and after rain. Extracts were made in tap water. The test plant was Beta vulgaris L.; its germination, root and shoot growth were evaluated at the 6th and 10th days after treatment.
Most of extracts inhibited the germination of sugar beet. In these experiments the phenological stage of the donor plant determined slightly the effectiveness of the extracts on sugar beet. Generally, significant differences existed between treatments only in cases of concentrated extracts.
Rainfall can modify the inhibitory effect of extracts (especially shoot extracts). Shoot extracts of young plants inhibited stronger germination and growth after rain than before rain. Density of cockleburs influenced the effect of extracts, as well. Generally, differences between the efficacy of extracts was larger after rain.
The results supported the hypothesis that the phenological stage and some environmental factors can modify allelopathy of cockleburs.

Product orientated sewage sludge composting technologies in the practice of AKSD Ltd.

In recent years the regulations of the EU unambiguously determine that the biodegradable wastes should be used for biogas production or composting. The direct use of sewage sludge in agriculture is limited by its hazardous microelement content, but it can be used effectively in composting. The limitation parameters can be extinguished with correct compost-mixture and technology variants. The exact determination of the technologies and mixtures result a stable, constant quality product. The compost, as a classified product, is friable structured. The end-product is a
homogeneous mould with good water capacity, does not contain any weed seeds and pathogenic organisms. The compost does not have a acidify effect on the soil. It is an effective fertilizer thanks to its macro and microelement content.

The effect of the preparation method on the physical and chemical characteristics of propolis tinctures

The effect of the preparation method was examined with regards to the physical and chemical characteristics of the propolis tincture, namely the extraction time and the ethanol content of the extraction solvent to the dry matter, polyphenol, flavonoid, phosphorus, calcium and copper concentration, respectively. The dry matter, the polyphenol and the flavonoid content were the lowest in the water extract of the propolis; however, significant increase was noticed depending on the extraction time. Significantly higher concentrations were found in 50 V/V% tinctures. The highest dry matter and flavonoid contents were analysed in 100 V/V% tinctures, whereas highest polyphenol content was found in 80 V/V% tinctures. However, the differences were not significant in several cases between latter tinctures. Moreover, the increase was not determined in some cases depending on the extraction time. Phosphorus and calcium concentrations were decreased depending on the increasing ethanol content, whereas copper concentration was increased up to 80 V/V%. Higher increase was found in the case of 0 and 50 V/V% extracts than in 80 and 100 V/V% tinctures. Moreover, in latter cases, no significant differences were found on several occasions, depending on the extraction time. There was no connection between the flavonoids and the calcium as well as the phosphorus content, whereas flavonoids may be made complex with copper. However, the amount of the possible complex was negligible.

Effects of fermented chicken manure products on the N mineralization rate of the soil using the incubation method

In 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.

The Effect of Sunburn on Fruit Quality of cv. Idared Apple

The aim of this study is to investigate the effect of sunburn injury on fruit quality parameters (colour-coverage, depth of affected tissue, fruit flesh firmness, soluble solids content) of apple.
The symptoms of sunburn injury appeared in concentric ring shape, differed from each other and surface colour-coverage. This can be due to the ratio of the injury. The authors observed the following colours on the fruit surface (from the epicentre of the blotch on the transversal diameter of the fruit) dark brown (strongly affected), light brown (moderately affected), pale red transition (poorly affected), red surface colour-coverage (not affected).
Sunburn of apple fruits is a surface injury caused by solar radiation, heat and low air relative humidity that in the initial phase results in a light corky layer, golden or bronze discolouration, and injuries to the epidermal tissue, in the surface exposed to radiation. Thus it detracts from its appearance, but in most cases, it would not cause serious damage to the epidermal tissue. The depth of affected tissue is not considerable, its values are between 1.5-2.0 mm generally. It is commonly known that the tissue structure of apple fruit is not homogeneous. Accordingly, the degree of injury shows some differences under the different parts of the fruit surface.
On the basis of flesh firmness research, the authors established that the measure of flesh firmness of the affected part of apple fruit increases with the effect of sunburn. The consequence of this is the suffered plant cells will die, the water content of this tissue decreases and the fruit gets harder. This water-loss caused the increase of soluble solids content.

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