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Mitigation of the effect of secondary salinization by micro soil conditioning
115-119Views:360This research has the general goal to meet the customization of agriculture in small scale farming. We are developing a technique using micro doses of soil conditioners and organic material applied in the root zone of vegetable crops. We expected to change the physical and chemical properties of the affected soil, which has been irrigated with salty water. Two different soil conditioners were tested. A lysimeter experiment including 8 simple drainage lysimeters was set up in the Research Institute of Karcag IAREF University of Debrecen in 2017. The main goal was to study the effect of different soil conditioners on the soil endangered by secondary salinization induced by irrigation with saline water. In order to compare the difference between the treatments, we collected soil samples, water samples, and determined the yields. Chili pepper (Capsicum annuum) was used as an indicator crop during one specific agricultural season. The technique called micro soil conditioning is rational because several reasons. The roles of the technique are various, for example it can serve as a source of carbon or a container for soil amendments and can minimize evaporation. We found this technique not to interfere with the chemical reaction or the interaction with the plants. However, the micro doses of soil amendments had the role to minimize the risk of soil degradation and do not significantly influence soil respiration. In addition, by improving soil properties, soil conditioning increases the leaching of the excess of salts from the root zone. In fact, this technique can decrease the cost of the inputs and improves the production of vegetables, and at the same time mitigates the effect of secondary salinization.
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Previous data on the relationship between the intensity of pruning and the degree of damage in integrated and organic applegrowing systems
47-52Views:225In Hungary, fruit growers are increasingly interested in environmentally friendly growing methods, such as organic and integrated systems. Vital is the establishment of a strengthened system of cultivar-pruning-plant protection in production technology. Consequently, our aim was to examine the susceptibility of apple cultivars to diseases and pests and the effect of pruning technique on diseases and pests in organic and integrated growing systems.
Two pathogens (Venturia inaequalis, Podosphaera leucotricha) and two pests (Leucoptera malifoliella, Pannonychus ulmi) were observed in organic and integrated systems under „strong” and „weak” pruning techniques. Our results on six cultivars showed that the pathogens and pests infested the trees more in the organic system, as compared to that of integrated production. The pruning technique affected mainly the susceptible
cultivars to diseases and pests. The „weak” pruning technique caused a higher level of diseases and pests infestations than the „strong” pruning technique, especially in the organic growing system. The likely reason is that the shoots grow fast and powerfully under “strong” pruning technique. This supports better preservation of the trees supported by susceptibility of plant tissues to diseases and pests. -
Defining agricultural cluster’s conceptual framework with Delphi technique
63-66Views:208The cluster concept is well defined in the literature, but its agricultural adaptation has not been detailed. A method is needed, which involves
experts into the study, who are able to confirm that the modell is correct and help to define the conceptual gaps. The Delphi technique is suitable
for the task. This is a well-structure, iterative future foresight technique, based on experts opinion about the research topic. The method leads to consensus by all means, but it also can have a negative outcome of the researcher's point of view, that's why we have to formulate scenarios.
The aim is not statistically significant result, but to build in new ideas into the modell with brainstorming. -
Examination of the decomposition of willow (Salix sp.), poplar (Populus sp.), reed (Phragmites australis) and mixed leaf litter with litterbag technique
111-115Views:273Leaf litter decomposition is one of the main ecological material cycle processes in waterfront areas. In this microcosm experiment, the rate of decomposition of the most frequently occurring dominant waterside plants were examined in the summer months of 2022 in a class “A” evaporation pan, using litterbag technique. The study provides information about the decomposition dynamics of willow (Salix sp.), poplar (Populus sp.), reed (Phragmites australis) and different leaf litter mixture combinations. Dry mass, exponential decay coefficient and the chemical parameters of the water (pH, conductivity, NH4+, PO43-, SO42-) were determined during the 84 days long experimental period. The weight loss curves showed negative exponential pattern in every case. On average, the different samples lost ~ 57% of their initial dry mass during the experimental period. The largest mass loss was measured in case of poplar (67.2%), while reed leaves had the smallest mass loss (47.25%). Based on the results, it cannot be proven, that mixed leaf litter accelerates the rate of decomposition.
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Routine microscopy examination of faecal samples as a tool for detection of common gastrointestinal parasites: a preliminary report from two Hungarian farms
63-66Views:307Gastrointestinal parasitism in ruminant animals is a cause of major economic loss incurred by the livestock industry. Regardless of the frequency of the adopted therapeutic and prophylactic deworming strategies, the parasitic burden in a farm should be assessed regularly. One of the most widely used techniques to do so is the microscopic faecal egg examination and faecal egg counting method. Despite the technique being almost a century old from its first adoption, the principle behind the newer techniques of faecal egg examination is the same. This technique is still being used in routine farm screening and monitoring gastrointestinal parasitic load and faecal egg count reduction testing to assess the anthelmintic efficacy of the drugs used. Thus, the tool remains a choice for preliminary screening for important parasites and the subsequent deworming strategy. Our study here was part of a larger survey on the treatment efficiency as well as a broad epidemiological study of the trichostrongyle parasites in Hungary. We present a preliminary report on the detection of common gastrointestinal parasites from two farms in Hungary, including a species-specific confirmatory microscopy for Haemonchus contortus eggs.
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The Possibilities of Futures and Option Hedge in Price Risk Management for GrainProduction
72-80Views:157The greataest risk tograin production is fluctuation in market prices, which is over 50% over the course of a year; and year by year, as well. There are real market circumstances in the grain market, instead of state guaranteed fix prices, which was the norm under the former political system.
According to the general opinion of producers, losses come from their defencelessness against buyers. The real situation is that price risk can be managed by suitable market strategy, and loss production can be avoided.
Hungary has a futures market (which is organized according to the CBOT system) in the grain sector, which is an unique institute in Europe. This organisation is suitable for hedge businesses and it has convenient technical and institutional background.
There are two possibilities to make hedge business. One of them is the short hedge with futures contract when the producer sells his product for long term if an acceptable profit is included in market price. In this case seller can protect himself against low market prices.
This technique can be considered as professional for price risk management, but possibly has financial cost because of the weak financial situation of Hungarian producers this solution seems expensive for them.
There is an other possibility in the Commodity Exchange for manage price risk, that is the option technique. This solution is suitable for insure prices as well, and has an other additional advantage, namely: there is no financial costs in this case. -
Opportunities of utilization of real-time ultrasound technique in beef cattle breeding
45-52Views:252The goal of the authors was to evaluate the repeatability and accuracy of real-time ultrasound technique under Hungarian conditions. Ribeye area was measured at first time on live animals, before the day of slaughtering with Falco 100 ultrasound equipment in Charolais fattening bulls. Ultrasound pictures were traced at two times by the same operator. After slaughtering, ribeye area (REA) was measured on the carcass by planimeter at the same anatomical point like ultrasound measurements. Statistical analysis was carried out to examine the relationship between carcass and ultrasound REA. After it, repeatabilty was established by comparing the ultrasound pictures twice.
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Novel Applications of Microwave Techniques in the Food and Environmental Industries
29-34Views:188During the microwave processing, despite the conventional heating, the material heats consistently inside. This property of microwave is utilized by drying and dehydration processes. The thermal sensitivity of raw materials of food industry requires development of gentle, fast and controllable technologies, which is realizable by means of combination of conventional and microwave techniques. The other important application area of the microwave technique is food industrial practice is enhancing the microbial safety of products, mainly by pasteurization processes. In recent time the strict environmental regulation necessitate developing more effective treatment of wastes, waste waters and sewage sludge. Because a part of these techniques are heat and power demanded, the microwave technique may be an alternative process in execution of sludge conditioning, drying or gasification and pyrolysis.
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Effect of sufficient and deficit irrigation with different salt inputs on the yield of cucumber
19-25Views:252Soil salinisation is considered one of the major environmental hazards threatening agricultural productivity and can be accentuated by climate change as well as the use of low-quality water in irrigation. This is the case in our study area which is affected by secondary salinisation due to the use of saline irrigation water for horticultural production. Deficit irrigation technique is implemented especially in arid and semiarid regions due to its potential to optimise water productivity while maintaining or increasing crop yield. The main objective of this study was to compare the effect of irrigation with sufficient (SD) and deficit (DD) doses. This research was carried out in Karcag in 2020. Cucumber was grown on a meadow chernozem soil and was irrigated with SD and DD of two irrigation water qualities. Soil moisture was monitored and crop yields were recorded. Despite the differences in quality and quantity of water, the application of less water by DD maintained the same yield as SD. We found a non-significant difference between the average soil moisture contents under the treatments (15.5 v/v% for SD and 13.5 v/v% for DD). Deficit irrigation can be an efficient technique due to its potential for improving water use efficiency, maintaining sufficient soil moisture content favourable for proper crop development and yield.
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Comparison of RAPD and AFLP Analysis in Some Maize (Zea mays L.) Lines and Hybrids
3-7Views:201The use of molecular markers to enhance plant breeding efforts is being widely studied. DNA-based fingerprinting technologies (RAPD and AFLP) have proven useful in genetic similarity studies. We estimated different maize (Zea mays L.) inbred lines and hybrids originated from mutant ones based on their genetic differences.
We carried out RAPD analysis with different primers and the 707 (CCCAACACCC) and 792 (CAACCCACAC) primers with 50% similarities provided quite good DNA fragments. By applying the DNA based-AFLP technique, we had very dense DNA fingerprinting. We differentiated 15-32 polymorphic bands, the highest number of bands were found in P-T/H-CA (32). AFLP seems to be the more efficient method of comparing genetic similarities/differences among different genotypes. -
Seed biology and possibility of improvement of seed germination capacity on Virginia mallow (Sida hermaphrodita L. Rusby)
71-76Views:238Sida hermephrodita or Virginia mallow is a perspective perennial herb in the Malvaceae family able to yield a biomass crop through the last two decades. Additionally, the plants have a lot of uses and benefits for instance it can use as a fodder crop, honey crop, ornamental plant in public gardens. It has favourable features like fast growing and resistance against the disease and climatic fluctuations, etc. Sida is in the beginning phase of domestication therefore it has a serious disadvantage: the low and slow germination as a big part of wild plants. Due to the expressly low germination percent the need of seed showing of driller is should tenfold, 200 thousand seeds/acre instead of 10–20 thousand what is not available and expensive Therefore practical purposes of our research of seed physiology was to increase the seed germination percent in a available, basically wild Sida population. In the first stage of our experiments we examined two factors relating to seed germination percent and seed germination power during our research: the influence of hot water treatment and the effect of exogenous or endogenous infection of seed. However, in our germination tests, utilizing scarified seeds with hot water (65 oC, 80 oC, 90 oC), from 29,3% to 46% germinated from those samples which were collected from the population of Sida hermaphrodita in Debrecen. The average germination for all season was 5–10% without treatment and rinsed using hot water up to almost 50%. When physically scarified used, the oldest seeds showed the best germination (46%) after the hot water operation in spite of the previous studies. We discovered that apparently there are close relationship between the seed fresh weight or water uptake capability and the percentage of infection. Following these recognition we modified our technique,in such a way that we fractionated the seeds based on their fresh weight/or relative density before we carried out the treatment. When we filtered the floating seeds on the surface of water, the hot water treatment was performed considerably better on the sunk seeds after separation. Therefore, by this special priming process we were able to reach 80% germination capacity of Virgina mallow seeds under laboratory conditions (26 oC without illumination).
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Horticulture applicability of 3D laser scanner
75-78Views:356As a result of the technological development, remote sensing instruments and methods have become widespread in all segments of life (from precision agriculture through architecture to medicine). Among the innovative development of remote sensing instruments the 3D laser scanner is overriding importance. The horticulture applicability of terrestrial laser scanning technique is innovation in the precision agriculture, because it could be determine the structure of trees and branches, the canopy extension, which can help to recognize some biophysical parameters. The examination was carried out with Leica ScanStation C10 terrestrial laser scanner in the Study and Regional Research Farm of the University of Debrecen near Pallag. In this article I present the measuring principle, the parameters and horticulture applicability of the terrestrial laser scanner.
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Application of laparoscopic artificial insemination in conventional Lacaune sheep farm using frozen-thawed semen
133-138Views:474The complex anatomical structure of the ewe reproductive tract accompanied with low quality of frozen ram semen for artificial insemination, resulted in a challenge with regard to using superior genotypes for reproductive ovine performance. Hence, improved genetics in ovine management has not been efficiently and widely used especially in undeveloped countries. Therefore, intrauterine semen deposition by laparoscopic insemination should be adopted in the current sheep production systems. Thus, this study aimed to assess the pregnancy rate and lambing rate of ewe inseminated by laparoscopic insemination techniques using frozen-thawed semen. The research used imported frozen semen from two rams of the Lacaune breed. Ewes were grouped according to age in years (1, 2 and 4). Before insemination, the semen was examined microscopically for its motility and viability and thereafter the laparoscopic artificial insemination technique was performed to 19 Lacaune breed ewes using frozen-thawed semen. The overall pregnancy and prolificacy rates were 31.57% and 42.10% respectively. Out of 2 ewes in the 1-year age group that were inseminated, only 1 ewe lambed representing 50%. However, from 16 ewes inseminated of four-year age group, 5 ewes lambed representing 31.25%. Significant difference based on age group was not evaluated due disproportionate of the data, (such that the data included 2 ewes in one-year-old age, 1 ewe in 2-year-old age and 16 ewes in 4-year-old age). Based on the ram semen, 33.33% and 30% of the inseminated ewes were pregnant from ram A and ram B semen respectively. However, in the case of prolificacy rate, 44.44% and 40 % of the ewes lambed from using semen of ram A and B, respectively. There was no significant difference (p>0.05) in pregnancy and prolificacy rates based on semen from the two rams. In conclusion, in this research study, ram semen had no significant effect on pregnancy and prolificacy rates using laparoscopic AI on Lacaune sheep. This could be due to the fact that the rams had very good quality semen. Evaluation of ram semen, accompanied with appropriate ewe selection based on age and rightful deposition of semen could lead to better and more consistent results. Overall this could contribute to the successful application of laparoscopic artificial insemination in Lacaune sheep production systems for enhanced productivity.
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New wonder of an old hormone: Hungarian sour cherry varieties as natural melatonin sources
65-72Views:342Agriculture has always been an important role in economy, food supplies, sustainability of society During our experimental work an effective extraction procedure has been developed for melatonin. Further chromatography was developed the quantitative and qualitative determination of melatonin. A compound that was equal to the standard was purified from the extract by preparative HPLC technique and the structure of the purified sample was confirmed by MALDI-TOF-MS and NMR analysis. Based on our measurements, harvested in the state of biological maturity Hungarian sour cherry cultivars contain high levels of melatonin.
Our results show that "VN4" variety has extremely high melatonin content, 9.893 ug g-1 and suggest that "VN4" which were selected from the "Bosnyák" varieties is melatonin accumulating. The average value of the melatonin content of Hungarian sour cherry cultivars is 2.319 ug g-1.
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Classification of a diffuse heavy metal polluted mining site using a spectral angle mapper
119-123Views:656Characterization of heavy metal polluted abandoned mining sites is complicated, as the spatial distribution of pollutants often changes dramatically.
In our study, a hyperspectral data analysis of the Gyöngyösoroszi abandoned Pb-Zn mine, located in northern Hungary, where Záray (1991) reported serious heavy metal contamination, was carried out using ENVI 4.3. In this area, galena (PbS), goethite (FeO(OH)), jarosite (KFe3(SO4)2(OH)6), sphalerite ((Zn, Fe)S) and pyrite (FeS2) were the predominant minerals in the alteration zones was chosen as the target mineral.
Spectral angle mapper (SAM) and BandMax classification techniques were applied to obtain rule mineral images. Each pixel in these rule images represents the similarity between the corresponding pixels in the hyperspectral image to a reference spectrum.
As a result of hyperspectral imagery the distribution of pyritic minerals (sphalerite, galena) in the area was defined. Both of the mineral formations occur, especially in mine tailings, the area of the ore preparatory, and the Szárazvölgyi flotation sludge reservoir. According to the results, jarosite and goethite have similar distributions to sphalerite and galena. The results showed that hyperspectral remote sensing is an effective tool for the
characterization of Pb, Zn and Fe containing minerals at the examined polluted sites and for modelling the distribution of heavy metals and minerals in extensive areas.
This classification method is a basis of further detailed investigations, based on field measurements, to map the heavy metal distribution of the studied area and to quantify the environmental risks caused by erosion, which include DEM (digital elevation model) and climatic and hydrological data sources. Furthermore, it can be used primarily to support the potentially applicable phytostabilization technique and to isolate hot spots where only ex-situ remediation techniques can be applied. -
Correlations Between the Crown Sizes, Pruning Times and Fruit Quality of Sour Cherry Cultivars
90-94Views:237To increase the intensiveness of sour cherry production, i.e. the use of smaller trees, it is necessary to adopt growth-moderating techniques rather than using dwarfing rootstocks. Apart from the traditional technique of using rootstocks that support stronger growth, new or rarely-used techniques and methods must be adopted. Pruning should be carried out in the summer rather than in the winter, the optimal period being 1-3 weeks after harvest.
A combination of the increase in favourable exposure-time and smaller crown sizes make higher tree densities (tree/ha) and better utilisation of the crown (specific cropload) possible.
The systematic use of summer pruning leads to better quality fruit. -
Fruit melanotic ringspot (FMRS) – a disease of resistant Capsicum genotypes infected with Tomato spotted wilt virus (TSWV) on the fruits
64-69Views:145Etiology of pepper fruit melanotic ringspot (FMRS) disease (Salamon, 2009) was studied on fruit samples collected in forced pepper populations. It was noticed that in spite of heavy thrips (Frankliniella occidentalis) infestations and of TSWV epidemy detected in the forcing houses, FMRS occurred only in plants having healthy foliage. Symptomatological surveys strongly suggested that FMRS appeared exclusively in specific pepper genotypes. The size of melanotic ringspots has been observed to grow at room temperature during postripening of diseased fruits. A mechanically transmitted plant virus was isolated from symptomatic parts of 9 white pepper fruits affected by FMRS. On test plants each of the virus isolates caused systemic symptoms characteristic to TSWV. Using cDNA/PCR technique and TSWV N-gene specific primers a ca. 300 bp long DNA fragment has been amplified from total nucleic acid extracted from symptomatic tissues but never from asymptomatic parts of the fruits showing FMRS. Plant progenies grown from seeds of FMRS diseased fruits segregated in respect of resistance and/or susceptibility to TSWV infection. TSWV was also detected in and isolated from three fruits showed non-melanotic yellow rings (one of them was infected with a tobamovirus, too). Seedlings derived from these fruits proved to be susceptible to TSWV. Based on the above results we could conclude that the FMRS disease developed on fruits of “cecei” type white peppers that carry a TSWV resistance gene, most likely the Tsw gene in heterozygous form. These fruits were infected with thrips transmitted TSWV and FRMS appeared as a hypersentive reaction (HR) manifested in fruits.
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Comparison of the technological background of aquaponic systems
47-52Views:606Aquaponics is the combined culture of fish and plants in recirculating aquaculture systems, an ecologically sustainable horticultural production technique with long traditions.
The objective of this study is to compare flood-and- drain, and the water crossflow system and examine the differences in the water quality, fish yield and plant growth parameters for Common carp (Cyprinus carpio) and basil (Ocimum basilicum). During the study, water quality parameters of two treatments were compared in temperatures, pH, EC and NO3¯N were significantly different (p <0.05). Leaf area of the basil plants grew to an average of 20.37 cm2 (± 9.02 cm2). The plants’ biomass production was significantly different (p< 0.05) in the two systems. The biomass production showed lower yield, 458.22 g (± 214.59 g) in the constant flow system that in the flood- and- drain system 692.9 g (± 175.82 g). Fish Growth parameters were better in constant flow system (FCR 5.48 g/g ± 0.19). However, the specific growth rate (SGR) demonstrated that fish grew faster in flood- and- drain system 1.38 %/day (± 0.29).
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Investigation of Salix alba and Populus tremula leaf litter decomposition in the area of Lake Balaton and Kis-Balaton Wetland
159-162Views:276Plant litter decomposition in inland waters contributes significantly to nutrient load, particularly in still waters, such as shallow lakes and wetlands. The decomposition rates of Salix alba and Populus tremula leaf litter was examined in Lake Balaton and Kis-Balaton Wetland, using litter bag technique. Leaf litter was incubated in small (ᴓ=3 mm) and large (ᴓ=900 μm) mesh size bags for the assessment of the relative contribution of macroinvertebrates to leaf litter decomposition. Dry mass, exponential decay coefficient and chemical parameters of water (pH, conductivity, NH4 +, NO3 -, SO4 2-, PO4 3-, Cl-) were determined. Leaf mass loss showed negative exponential pattern during the 168 days of the decomposition period. Leaf litter mass loss generally did not differ between the small and large mesh sizes, suggesting that macroinvertebrates generally have a negligible role in leaf decomposition in the winter period.
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Examination of repeatability of ultrasound scanning technique in young bulls
43-48Views:340The author’s goal with the methodology examination was to determine repeatability of taking and evaluating ultrasound images. In the trial an operator person took two images about the ribeye area and rump fat thickness (P8) of every young bull, which were measured by the same person in four repetitions. Also, we had altogether eight images about the same part of the body. Images were collected using Falco 100 (Pie Medical) real-time ultrasonic scanner equipped with an ASP 3,5 MHz, 18 cm linear array transducer.
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The potential use of Pediococcus spp. probiotic in aquaculture: A review
99-106Views:475Aquaculture production has significantly increased over the previous few decades. However, antibiotics have been implemented regularly and extensively to overcome outbreaks of pathogens in aquaculture to cover the human needs for animal protein, leading to the appearance of resistant strains that may cause serious damages in the environment and also human health. In the last few years, the implementation of probiotics as an alternative technique to antibiotics use in fish production has achieved promising results in aquaculture due to their beneficial impact on fish health and growth performance. Among different types of probiotics, the Pediococcus spp. bacteria stand out as a promising probiotic for their beneficial impact to aquaculture. Thus, the current study has been conducted to give an overview about the interactions between Pediococcus spp. and aquaculture. In addition, this review highlights the role of Pediococcus spp in promoting growth performance, improving feed conversion ratios and the intestinal architecture, enhancing the immune response and inhibiting fish pathogens, thereby preventing or at least reducing the use of antibiotics. Practical use of Pediococcus spp. probiotic in aquaculture as feed additives through selected case studies is also considered.
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Development of seed analyses by means of various matrix solutions and the MALDI-TOF MS technique
53-57Views:670The earth's population is growing steadily, currently accounting for about 7.3 billion people. Population growth causes food demand to rise, approximately 36 million people die each year due to starvation or related diseases. One solution to this problem is the continuous examination and development of the agricultural economy. In this study, matrix-assisted laser desorption/ionization time-of-flight mass spectrometer (MALDI -TOF MS) were used to analyse of sunflower, soybean and hemp. In order to analyse the protein of maize, this method has already been applied. However, for sunflower, soy and hemp, it is necessary to develop a sample preparation method. Choosing the optimal matrix solution for ionization the traget molecule is an essential part of developing the method. Our aim is to compare two different matrix solutions (α-HCCA, SA matrix), based on the properties (intensity, noise ratio, value of spectra) of the spectra.
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Studies on the Fusarium stalk rot infection of the maize genotypes using the Findex percentage and a computerised image analysis program
45-51Views:211In a continental climate, the pathogens causing the most serious problems are species belonging to the Fusarium genus. When the pathogen attacks the stalk, the plant dies earlier, reducing grain filling and resulting in small, light ears. In addition, the stalks break or lodge, resulting in further yield losses from ears that cannot be harvested. During the three years of the experiment, 14 inbred lines were examined. The genotypes were sown in a two-factor split-plot design with four replications, with the genotypes in the main plots and four treatments in the subplots: two Fusarium graminearum isolates (1. FG36, 2. FGH4), 3. sterile kernels, 4. untreated control. The results experiments showed significant differences between the genotypes for resistance to fusarium stalk rot. Among the inbred lines the best resistance to fusarium stalk rot was exhibited by P06 and P07, both of which were related to ISSS. The precision and sensitivity of disease evaluations carried out visually and using image analysis software were compared in the experiment, and with two exceptions the CV values were lower for the image analysis. As the CV for measurements can be considered as a relative error, it can be stated that image analysis is the more precise of the two methods, so this technique gives a more accurate picture of the extent of stalk rot. The extent of stalk rot developing in response to natural infection is extremely environment-dependent, so the use of artificial inoculation is recommended for selection trials.
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Comparative studies to model bioavailability of pesticides in distinctive soil types
17-23Views:157Bioavailability of pesticides is determined by two major factors: soil characteristics and pesticides’ chemical feature. These factors result in a definite adsorption capability whose extent varies on a large scale. By revealing interactions between pesticides and soils it is of high interest to model bioavailability of widely used pesticides, as it is a key element in terms of prospective toxicological aspects. Our work signifies steps forward improving pesticide soil mobility prediction models as we created model systems representing correctly natural relations. Comparison of different solvent extraction methods proved to be an efficient tool to gain information on the bioavailability of some widely used pesticides as well as to model actual environmental processes.
Comprehensive comparison has been made between different experimental methods by applying 5 extraction models showing diverse efficiency in extracting capability of pesticides. In some cases chloroform excelled in mobilizing pesticides from soil, however mostly application of humic acid solution as extraction model was found to be at least as efficient as methanol, chloroform or CaCl2-solution.
Four chemically much different pesticide (simazine, acetochlor, chlorpyrifos and diuron) were applied to two soil types (both sandy and brown forest). The extracted amounts were determined by GC/MS technique. Adsorption coefficients (Kd) were also calculated for the examined samples.
Obtained results for Kd indicated that chemical feature of pesticides seemed to be of utmost importance in terms of soil binding capability preceding the relevance of soil characteristics. Adsorption capability of chlorpyrifos proved to be the most pronounced preceding simazine and the least prone to bind to soil acetochlor and diuron -
Comparison of sample preparation methods for the identification of Staphylococcus Aureus by MALDI-FOF MS
9-14Views:468Coagulase-positive staphylococci include 3 species, Staphylococcus aureus, S. hyicus and S. intermedius. Of these three species, S. aureus is the most well-known human pathogen. S. aureus is part of the human and animal normal microbiota, however, it is capable of producing several staphylococcal enterotoxins (SEs) that cause intoxication symptoms of varying intensity in humans after consuming contaminated food. Selective media which are used for the determination of coagulase-positive staphylococci from foods are not able to identify isolates at a species. With the MALDI-TOF MS technique, we can identify S. aureus cheaper and faster than by using molecular methods. This paper describes the results of the study of the presence of coagulase-positive staphylococci and S. aureus in many food products, and the application of three sample preparation methods: direct sample preparation, formic acid suspension and ethanol extraction.