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Evaluation of the microbial soil quality indicators in agricultural soils from Crisurilor Plain
79-80Views:218The researches were carried out in 2010 and 2011 on the haplic luvisol cultivated in three variant such as: pasture, cropland, and orchards. Based on the total number of microorganisms monitored in the haplic luvisol (aerobic mesophilic heterotrophs, yeast and mould, Actinomycetes, nitrogen fixing bacteria and nitrifying bacteria) was calculated the bacterial indicators of soil quality (BISQ) and was appreciate the bacterial potential of the haplic luvisol. Seasonal analyses were carried out, and annual BISQs have been calculated too. The values of the bacterial indicators of the haplic luvisol in different cultivation conditions (pasture, cropland and orchards) indicate a high density of the bacterial groups in 2010 and 2011. In 2010 the values of the BISQs are included between 3.617 (minimum in autumn, in pasture) and 5.458 (maximum, in spring, in pasture). In 2011, the minimum value (3.622) was registered in pasture, in autumn, and the maximum value (4.851) in the haplic luvisol cultivated with maize, in spring. In 2010 and 2011, based on the bacterial indicators of the soil quality values, on the first position is the cropland (4.750, 4.721) followed by orchards (4.615, 3.985) and pasture (4.537, 3.758).
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Improved soil and tomato quality by some biofertilizer products
93-105Views:447The use of microbial inoculums is a part of sustainable agricultural practices. Among various bioeffectors, the phosphorus-mobilizing bacteria are frequently used.
The objective of this study is to investigate the effect of some industrial biofertilizer inoculums, of containing P-mobilizing bacteria on the quantity and some quality parameters of tomato fruits. Spore-forming industrial Bacillus amyloliquefaciens FZB42 (Rhizovital) as single inoculums and combinations with other Bacillus strains (Biorex) were applied on Solanum lycopersicon Mill. var. Mobil test plant. Soil microbial counts, phosphorus availability, yield and fruit quality, such as total soluble solids (TSS) content and sugars (glucose, fructose) were assessed. The results found that single industrial inoculums of FZB42 product had positive effect on P-availability and fruit quality in the pots. Fruit quality parameters, TSS content, soluble sugars were significantly improved (p<0.05). Such better fruit taste was correlated significantly by the most probable number (MPN) microbial counts. Use of such bioeffector products is supported by the positive interrelation among measured soil characteristics and inside healthy quality parameters of tomato fruits.
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The examination of poultry feather digestility for biogas production
113-118Views:325The aim of this research was the elaboration of the technological parameters of biological digestion and biogas production from poultry feather produced in large quantities by slaughterhouses. Feather protein was digested by Bacillus licheniformis, keratin desintegrator bacteria. Investigations focused on the optimalization of parameters influencing poultry feather biodegradation. The optimal range of pH, temperature, feather size and bacillus:feather ratio were determined in the experiments as well as the analysis of relationship between the examined parameters. In order to be able to track the dinamics of the biodegradation, we determined the extintion level of the liquid phase of the biodegraded material in the different experimental treatments. The results showed that the rate of hydrolisis was significantly higher in the treatments with bacteria than in the treatments without it. The most extensive digestion were observed in case of 1:3 feather:water ratio. The highest intensity of feather digestion were detected in the treatment with 1% microbe ratio.
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Microbiological quality of bulk tank raw milk from two dairy farms in Hajdú-Bihar County, Hungary
105-112Views:637Two 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.
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The effect of different microbial preparations on some soil characteristics
83-86Views:332In 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. -
Effect of plant extract against opportunist human pathogen soil bacteria
89-93Views:223Our experiments have repeatedly shown that the extract of ragweed (Ambrosia artemisiifolia) is an antifungal and antibacterial component.
In our paper we tested of the biological activity of the herbal substance against opportunistic human pathogenic bacteria strains (Staphylococcus
aureus 110003 and 25923; Staphylococcus saprophyticus 110008). Our laboratory tests show that the extract is bacteriostatic and in several cases bactericid. We can assume that from the the agricultural and public health aspects can be extremely dangerous weed, contains biologically active components and it may be suitable for the prepare of antibacterial agents. -
The dynamics of biodiversity structure of soil microorganisms under the impact of biopreparations during potato growing season
67-74Views:273The use of biological preparations such as Phytotsid and Planryz contributes the increase of the general number of soil bacteria population by 13.0–36.1% in the case of potato variety Scarbnytsya and by 4.5–24.6% for potato variety Oberig compared with control. It also increases the number of saprophyte microflora, which compete with plant pathogens, micromycetes, and causes 1.2–1.8 times reduction in the number of soil fungi – Fusarium and Alternaria. During the application of Rovral Akvaflo the Shannon ecological index of species biodiversity is lower than during the biopreparation use. The decrease of species biodiversity was observed as well as strengthening the dominance of some species (dark pigmentation in fungi).
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Evaluation some important microbiological parameters of the carbon cycle in chernozem soils profiles
33-39Views:410Some chemical and microbiological properties of the carbon cycle were investigated in three chernozem soil profiles. The soil profiles originated from a long term fertilization experiment (potato) of the University of Debrecen, Látókép, Kryvyi Rig Botanic Garden (grassland) and a large-scale farm (sunflower) of Ukraine. The results of the organic C-content, total number of bacteria, microscopical fungi, cellulose decomposing bacteria, CO2-production, microbial biomass carbon and saccharase and dehydrogenase activities were compared and evaluated with the help of correlation analyses. Close correlation was found between the organic carbon content and the number of microscopical fungi,, saccharase and dehydrogenase enzymes’ activities, as well as close correlation was found between the dehydrogenase activity and microbial biomass-C and saccharase activity.
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Environment-friendly nutrient supply in the area of NYÍRERDŐ Zrt
111-116Views:259The widespread realization of environmental friendly management is an important segment of seeking sustainable technological and
technical solutions. The methods ensuring sustainable development by exploiting natural facilities have great significance. Bacteria-based
biofertilizers and wood ash are good examples of them. Using bacteria-based biofertilizer means a kind of biofertilization that is using the
possibilities provided by the ecosystem. -
Examination the effects of different herbicides on the soil microorganisms of a calcareous chernozem
121-126Views:220Pesticides 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. -
Effects of combined nutrient supply treatments on some physiological parameters of autumn wheat
241-251Views:304The Fleischmann Rudolf Research Institute in Kompolt is not only famous for plant breeding but the institute also surveys the effects of different nutrient supply methods since 1918. In 2017, we joined this research supported by EFOP 3.6.1 project. Our aim was to investigate photochemical processes – which is one of the most determinant in case of yield – of crops by in vivo field measurements. We measured the chlorophyll content of leaves using Minolta SPAD 502. We used miniPAM fluorometer to determine actual photochemical efficiency and non-photochemical quenching of PSII during natural light conditions and also to evaluate the pigment (chlorophylls and carotenoids) and water content of leaves we applied field spectrophotometer (ASD FieldSpecPro 3). We utilized these methods by various treatments (1. treatment with soil bacteria + head and base fertilizer; 2. treated by only head fertilizer; 3. treated by only base-fertilizer) in field experiment of autumn wheat (4.1–2.43–1.19 ha) in June, 2017. The difference between treatments was clearly detectable. In the case of the first treatment, physiological processes were more intense and the ripening occurred earlier. The obtained yield was the highest in the case of the area treated by soil bacterial. Based on the results, the first treatment can be recommended in practice.
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The effect of washing for the shelf-life parameters of spinach (Spinacia oleracea L.)
131-135Views:543Spinach is a very popular green leafy vegetable because of its versatile usage and beneficial for the health. However, spinach may contain several pathogen bacteria: Escherichia coli, Klebsiella spp., Salmonella spp., Enterobacter spp., Citrobacter spp., Shigella spp. and Listeria monocytogenes, which can cause several serious health problems. This study investigates the effects of washing with citric acid for the shelf-life parameters of spinach in comparison to the effect of washing with water and control. Washing of spinach with 0.5% citric acid solution decreased the elasticity of the spinach leaves, as well as the chlorophyll content. On the other hand, the total plate count, as well as the yeast and mold count could be decreased with this treatment, but difference was not detectable at the forth storage day. The fecal indicator E. coli did not change, indicating washing was not effective in this case. Further optimisation of treatment and storage conditions may decrease microbial risk of fresh spinach consumption without decreasing its sensory quality.
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The effect of apoplastic pH on the nutrient uptake
65-71Views:216The pH of soil and rhizosphare –around the roots- determine the mobility and solubility of nutrients. The exudates organic acids of plant able to modify the pH, as well as the microorganisms also take part in mobilization of nutrients. The nutrient solve mostly in mildly acidic and neutral pH. The either assumption of utilization of nutrients is the uptake by roots and of course uptake to the cells to take part in metabolism. The pH of apoplast fluid determines the solubility and uptake of nutrients to the cells.
The aim of this study was to examine the effect of nutrient solution and apoplastic pH together with a bacteria based biofertiliser (Phylazonit MC®) on nutrient uptake and pH of apoplast fluid in case of nutrient solution grown plants in laboratory experiment. According to my results, the bicarbonate increased the pH of nutrient solution in due to influence the solubility and uptake of nutrients. The given bicarbonate to the nutrient solution and infiltrated into the apoplazma also modified the pH of the apoplast fluid of the test plants. The effect of bicarbonate and biofertilizer were different on the pH of the apoplast fluid and nutrient solution in nutrient solution experiment. -
Does the Hooded Crow (Corvus cornix) harbour vancomycin-resistant enterococci in Hungary?
5-8Views:433Vancomycin resistant enterococci (VRE) are high priority nosocomial bacteria with a potential for zoonotic transmission. Thus, its emergence outside health establishments is a major concern. In order to study the prevalence of VRE in wildlife, we collected 221 faecal samples from free-ranging Hooded Crow (Corvus cornix) from urban and rural habitats in Hungary, from March to August 2020. The screening for resistant enterococci was done using bile esculin azide (BEA) agar supplemented with Vancomycin, specific to the screening of VRE. None of the samples from either habitat types yielded VRE. It seems that Hooded Crows from Hungary do not necessarily constitute a reservoir of VREs at present. Nonetheless, a continuous surveillance of VRE in wildlife would be judicious.
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Production of novel fermented milks
303-305Views:287The objective of this research was to test the influence of various natural substances on acid production, growth, and viability of characteristic microorganisms in yogurt and probiotic fermented dairy foods. Oligofructose, inulin, honey, and the dried biomass of Spirulina (Arthrospira) platensis were found to stimulate the growth rate and acid production activity of the major thermophilic diary cultures tested and, in addition to this, the presence of the aforementioned substrates also improved the survival of starter bacteria in fermented milk products during storage. The reduced production time of cultured milks resulted in increased production efficiency. The stimulatory and/or protective effect of oligofructose,
inulin, honey, and Spirulina on Bifidobacterium spp. is probably the most important finding of this study because bifidobacteria do not grow well in milk and they have low survival rates in conventional fermented milks. Some of the bioactive substances tested were also capable of exerting an antifungal effect on spoilage yeasts and molds, and improving the nutritional and sensory properties of the final product, thus providing a new opportunity for manufacture of functional fermented dairy foods. -
Pre-treatment of wastes containing keratin in industrial conditions
59-64Views:552The 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. -
Utilization and examination of red, elemental selenium nano spheres, produced by fermentation technology, in animal tests
245-247Views:349In our experiments we tested the toxicity of Nano-Se and LactoMicroSel® compared with other organic and inorganic selenium forms, in case of a subakut animal test. We produced the Nano-Se and LactoMicroSel® by probiotic lactic acid bacteria in our laboratory. (Prokisch et al., 2010; Eszenyi et al., 2011). We mixed the inorganic selenium forms, selenite and selenate, the organic form, Sel-Plex® and our products, Nano-Se and LactoMicroSel® into the standard food of laboratory mice and we fed them for two consecutive weeks. After the extermination we observed mortality, the change of body mass,and measured the blood antioxidant capacity with FRAP method.
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The Effect of the Mineral Content of the Leg-Horn and the Age of Sheep on the Mechanical Parameters of the Horn
42-45Views:184Species and individual animals with hard leg-horn have higher resistance against foot diseases. The reason for this is the fact, that bacteria can penetrate the hard leg-horn with more difficulty than the soft leg-horn, and in this way it is also more difficult for them to cause an illness. From among the mechanical parameters of the leg-horn the P = 0.1% negative linear correlation between the hardness and the water contents of the horn is significant. There is a positive linear correlation between the shock resistance and the water contents of the leg-horn. In the case of air-dry horn (with less than 8% water contents) there is a positive linear correlation between the Ca- and Zn contents as well as the Ca:P ratio and the hardness of the horn. The results suggest that the wider the Ca:P ratio of the horn, the harder the horn is, while the water content is the same. The leg-horn of the Hungarian Merino ewes have larger Ca contents and wider Ca:P ratio than juvenile animals have. This is why the juvenile animals with a softer leg-horn can be more susceptive to foot diseases than the older animals.
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Effect of bacteria containing bio-fertilizer on Cd-tolerance of corn and sunflower seedlings in nutrient solution
15-21Views:205Bio-fertilizers promote the nutrition uptake, firstly enhance the baring and mobility of nutrients, on the other hand biofertilizers elevate nutrient uptake in direct way. Although there are a lot of questions about their application in polluted soils. The cadmium ion is easily collectable and also transportable inside plants. Thus the Cd can get into the food-chain causing public health problems. The cadmium treatment decreases the dry matter accumulation, and the intensity of photosynthesis at the experimental plants, while the treatments with bio-fertilizer increased these parameters. The cadmium accumulated in the roots, the transport to the shoots was low. We came to the conclusion, that –because of the different nutrient-uptake systemthe sunflower took up more cadmium. Using bacterium containing bio-fertilizer the toxic effect of cadmium was moderated. By our experimental results the use of Phylazonit is offered under contaminated conditions.
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Dietary fibre prevalence and its role in human nutrition
9-13Views:455The role of dietary fibre and its impact on health is increasing. It is worth noting that their beneficial effects on the body are becoming more widely known, but their consumption is still below the recommended daily intake from food. Dietary fibre, as a class of compounds, includes a mixture of plant carbohydrate polymers, both oligosaccharides and polysaccharides. Dietary fibre has been linked to a number of diseases, as its consumption can reduce the risk of cardiovascular disease and type 2 diabetes. They influence the composition of the bacteria present in the human gut. Consuming the right quantity and quality of dietary fibre can play a role in the prevention of certain types of cancer. Nowadays, it is common to produce various fibre-enriched foods, called functional foods, because of the beneficial effects they have previously had on the body. In the present work we want to give a general description of dietary fibre and its role in the body.
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Examination of feral pigeon populations at animal breeding farms
52-56Views:347In the course of our examination, we assessed biometric data that determine gender, we evaluated sexual activity, measured the nourishment and necropsies of two feral pigeon populations feeding and nesting at animal breeding farms. The changes in the body weight of the different genders were significant on both farms (p<0.05).
The body weight and the crop volume of the birds were not significantly different at the examined farms.
On both farms, the elemental food source of the birds was the fodder and corn kernels given to cattle, and was supplemented by that of the pigeons living at the Debrecen farm with food from surrounding farms and with other seeds (pea, millet, rye).
By the examination of the genitals, the birds collected from the Nyírbátor farm showed sexual activity from the beginning of spring, and in the summertime decreasing activity is characteristic, while the pigeons from the Debrecen farm are only active from the summer months. In the course of the examinations in the Veterinary Institute of Debrecen, the birds proved to be free of parasites and the results of the Newcastle disease analysis were negative as well. The bacteriologic analyses showed a different proportion of E.coli, Pasteurella multicoda, haemolysing Staphylococcus bacteria at the two cattle farms. During the examinations for the statement of Salmonellas, this causative agent was stated only in case of birds that spend nights and nested in the town, which allude to human origin. We demonstrated Eimeria oocysts during the parasitological examination of the fecal samples in 5 cases at the Debrecen, and in 1 case at the Nyírbátor farm. -
Change of soil nitrogen content in a long term fertilization experiment
39-44Views:381The 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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Pathogenic fungal pathogens and diseases: a mini review of effects on maize production
93-102Views:259Maize, the most important cereal globally in terms of nutrition and income, is highly susceptible to biotic stresses caused by various pathogens, including fungi, bacteria, viruses, nematodes, and parasitic plants. This review gives an account of the epidemiology, diversity, and effect of fungal diseases on maize, with a focus on common pathogens, namely Ustilago sp. and Fusarium sp. Additionally, the review explores the major contributors to the pathogen and disease development, namely: soil quality, temperature, and humidity. Clarity is made herein about the damages and effects on maize growth, including development, yield, and grain quality, with marked economic losses recorded annually. The increasing threat of climate change escalates the dangers, pointing out the urgency for sustainable control strategies of the diseases. Conventional methods of using chemicals have been rendered inadequate for maize fungal disease control, underscoring the need for applying biopesticides and natural products obtained from microorganisms as innovative, remediation strategies. Together with these innovations are biocontrol agents that provide better solutions for reducing the reliance on chemical formulations as well as strengthening a healthier agricultural environment. Finally, a comprehensive understanding of the interaction between maize pathogens and environmental determinants is vital for the development of more effective integrated pest management strategies to enhance maize productivity and subsequent food safety.
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Overview of the evolutionary history and the role in citric acid production of alternative oxidase
83-88Views:293All organisms are exposed to countless environmental effects, which influence in a disadvantageous way their life processes. They continuously adapt to the changing conditions and respond to the stress impacts by defence mechanisms. Through different signal transduction pathways they are able to increase or decrease the expression of their genes and consequently modify their metabolic processes. My interest focuses on alternative oxidase (AOX) enzyme whose expression is often increased under biotic and abiotic stress. The so far proven and putative functions of the AOX play a role in the ability of organisms to adapt to different conditions, such as heavy metals accumulation, pathogenic infection, oxidative stress and lack of oxygen or nutrients.
AOX is a member of the di-iron carboxylate protein family. Members of the di-iron carboxylate protein family are present in all kingdoms of life. They are considered to have ancient origin. It is believed that their sulfide-resistant and oxygen-reducing ability played a role in the survival of organisms during the transition between the anaerobic and the aerobic world. It is assumed that the AOX arose in eukaryotes through a primary endosymbiotic event, and this event made possible the development of mitochondria. Afterwords, vertical inheritance, and secondary and tertiary endosimbiotic events led to its spread among eukaryotes. It is assumed that bacteria obtained AOX by horizontal gene transfer from plants.
AOX-catalyzed alternative respiration plays an important role in the operation of energy-producing and biosynthesizing system of microorganisms. In these cases, the regeneration of reduced cofactors is an essential condition, and therefore may be rate-limiting for biotechnological processes, including the citric acid production.
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Different ideas on the pathogenesis and treatment of swine edema-disease
45-48Views:364Although literature data associate the reason of swine edema-disease with certain serotypes of Escherichia coli bacteria, the authors assume that the primary cause of edema is more different. Susceptible agents and factors, mostly of feed compound are involved. During the digestion of some feed-origin protein opiate-like metabolites, exorphins arise, simultaneously arrest the release of acetylcholine. Consequences of acetylcholine shortage are spasm of sphincters (mostly pylorus), intestine-dilatation, contraction of bladder-sphincter, and urine retention. The endorphins and exorphins intensify the insulin release from the pancreas, hypoglycemia evolves, which is associated with loss of balance. According to the authors in edema-disease piglet dies because of hypoglycemia.