Search
Search Results
-
Identification and specific variety of actinomyces of streptomycetes genus in some chernozems of Ukraine
67-74Views:135Is definite the quantitative and quality composition of chernozem usual and southern streptomycetes cenosis. It is rotined that humus horizons of chernozem usual more biogenic, than chernozem southern. Analysis of specific structure of streptomycetes association and calculation of some biodiversity indexes by Margalef, Berger-Parker and Serensen it was allowed to set the specific features of forming of these microorganisms cenosis in investigated soils.
-
Using crop analysis in the precision nutrient supply system of maize
183-186Views:210The effect of the N, P and K supplies of soil on the grain yield and N, P and K status of maize was studied in a long-term mineral fertilisation experiment between 2001 and 2008 and nutrient supply limit values were determined to plant analysis. Based on the interaction between the N concentrtion of maize leaves measured at the beginnig of tasseling and grain yield, the satisfactory limit value of N supply to reach 10–14 t ha-1 yield was between 2.0–4.0%. Leaf analysis at the beginning of tasselling indicated that better P and K supplies were associated with a higher P and K concentration in the maize leaves. Correlation analysis on the P concentration of the maize leaves and the grain yield showed that at a grain yield level of 10–14 t ha-1 a P concentration of 0.20–0.37% represented a satisfactory P supply level. The satisfactory K supply limit value to reach 10–14
t ha-1 grain yield was 1.5–2.6%. -
Phytopatological properties of symbiotic Rhizoctonia solani strains associated to orchids
65-71Views:296The mycobiota of the Orchidarium of ELTE Botanical Garden (Budapest) has been studied applying aerobiological methods and isolating of tissue samples taken from 92 individuals of sixty orchid species. Among isolated basidiomycetaceous fungi 13 strains of Rhizoctonia solani were surviving in axenic culture. These symbiotic R. solani strains proved to be pathogenic on 24 cultivated plant species at varying degree. The symptoms of disease caused by R. solani strains isolated from orchids did not differ from that caused by reference strains. Three groups of strains could be separated regardless of their source or aggressivity. The host plants clustered into two groups, and their taxonomic position had no role in this respect. In general, we can assume that orchid associated Rhizoctonia strains are potential plant pathogens, and removed or withdrawn orchid stools should be treated as hazardous waste.
-
Analysis of maize and sunflower plants treated by molybdenum in rhizobox experiment
11-14Views:548In this study, maize (Zea mays L. cv. Norma SC) and sunflower (Helianthus annuus L. cv Arena PR) seedlings treated by molybdenum (Mo) that were cultivated in special plant growth boxes, known as rhizoboxes. During our research we tried to examine whether increasing molybdenum (Mo) concentration effects on the dry mass and absorption of some elements (molybdenum, iron, sulphur) of shoots and roots of experimental plants.
In this experiment calcareous chernozem soil was used and Mo was supplemented into the soil as ammonium molybdate [(NH4)6Mo7O24.4H2O] in four different concentrations as follow: 0 (control), 30, 90 and 270 mg kg-1.
In this study we found that molybdenum in small amount (30 mg kg-1) affected positively on growth of maize and sunflower seedlings, however, further increase of Mo content reduced the dry weights of shoots and roots. In case of maize the highest Mo treatment (270 mg kg-1) and in case of sunflower 90 mg kg-1 treatment caused a significant reduction in plant growth.
In addition, we observed that molybdenum levels in seedling were significantly elevated with increasing the concentration of molybdenum treatment in comparison with control but the applied molybdenum treatments did not affect iron and sulphur concentration in all cases significantly.
-
The effects of drought stress on soybean (Glycine max (L.) Merr.) growth, physiology and quality – Review
19-24Views:430Abiotic stresses are one of the most limiting factors inhibit plant's growth, leading to a serious production loss. Drought stress is one of the most destructive abiotic stresses and is still increasing year after year resulting in serious yield losses in many regions of the world,
consequently, affecting world’s food security for the increasing world population. Soybean is an important grain legume. It is one of the five major crops in the world, an essential source of oil, protein, macronutrients and minerals, and it is known as the main source of plant oil and protein. Harvested area of soybean is increasing globally year after year. However, soybean is the highest drought stress sensitive crop, the water deficit influences the physiology, production and seed composition of this crop. We introduce a review for literatures concerning the changes of the above traits of soybean exposed to drought stress, with past explanations for these changes. -
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.
-
Comparison of the physiological responses of an oil-pumpkin cultivar and hybrid under different nitrogen supply conditions
65-69Views:492Cucurbita pepo var. styriaca is known as a medicinal crop among other cucurbits. The benefits of cucurbits fruits are very important in terms of human health, purification of blood, removal of constipation, digestion and supplying energy. The mutant styrian oil-pumpkin (Cucurbita pepo L. convar. Pepo var. styriaca Greb.) exposes a complete lack of lignification of the seed testa. For this reason, this kind of naked pumpkin seed is more consumable as snack than other seeds. The vegetative growth of plants is crucial for fruit production. Nitrogen is the most imperative element for the proper vegetative growth and development of plants which significantly increases and enhances yield and its quality by playing a vital role in the biochemical and physiological functions of plants.
Field studies were conducted to study the effect of nitrogen nutrition on certain physiological parameters and their differences between the styrian oil pumpkin hybrid and cultivar (Gleisdorfi Classic cultivar and GL Rustical hybrid). The small block experiment was carried out based on a factorial experiment with a completely randomised block design and four replications in the Research Institute of Nyíregyháza during the summer period of 2017 and 2018. Three different concentrations of nitrogen fertiliser was applied at sowing. Photosynthetic pigments (chlorophyll-a, -b and carotenoids) were analysed as one of the basic factor of efficient photosynthesis. The yields of two genotypes were also measured in all treatments as seed-weight. The contents of photosynthetic pigments were higher in the oil-pumpkin hybrid, mainly the carotenoids in 2018. The vegetation period of 2018 was drier than in 2017, the hybrid oil-pupmkin was more efficient in stress tolerance than the cultivar with higher carotenoids pool. The obtained yield was more pronounced in the oil-pumpkin hybrid than the cultivar in all examined years. The hybrid GL Rustical was more sensitive to nitrogen treatment than the cultivar Gleisdorfi Classic.
-
Evaluation of KCl-EDTA-, CaCl2- DTPA-, CaCl2-DTPA-TEA extractants for estimating available Cu in soils
5-9Views:379KCl-EDTA-, CaCl2-DTPA-, CaCl2-DTPA-TEA extraction
methods were compared to determine the plant available Cu
amounts in the soil samples. In the soil extracts, the amounts of
copper were measurable. In the buffered CaCl2-DTPA-TEA
extracts, data showed the lowest values.
On the applied soils, a correlation was observed between
plant removal and soil Cu using extractants mentioned above. The
closest correlation appeared in the case of sandy soils.
From the results of statistical analysis, it appears that soil
properties may play role in the efficiency of the extraction using
either CaCl2-DTPA or KCl-EDTA solutions.
To establish more reliable relations, further studies with
different types of soils are needed. -
Management of phytopathogens by application of green nanobiotechnology: Emerging trends and challenges
15-22Views:577Nanotechnology is highly interdisciplinary and important research area in modern science. The use of nanomaterials offer major advantages due to their unique size, shape and significantly improved physical, chemical, biological and antimicrobial properties. Physicochemical and antimicrobial properties of metal nanoparticles have received much attention of researchers. There are different methods i.e. chemical, physical and biological for synthesis of nanoparticles. Chemical and physical methods have some limitations, and therefore, biological methods are needed to develop environment-friendly synthesis of nanoparticles. Moreover, biological method for the production of nanoparticles is simpler than chemical method as biological agents secrete large amount of enzymes, which reduce metals and can be responsible for the synthesis and capping on nanoparticles.
Biological systems for nanoparticle synthesis include plants, fungi, bacteria, yeasts, and actinomycetes. Many plant species including Opuntia ficus-indica, Azardirachta indica, Lawsonia inermis, Triticum aestivum, Hydrilla verticillata, Citrus medica, Catharanthus roseus, Avena sativa, etc., bacteria, such as Bacillus subtilis, Sulfate-Reducing Bacteria, Pseudomonas stutzeri, Lactobacillus sp., Klebsiella aerogenes, Torulopsis sp., and fungi, like Fusarium spp. Aspergillus spp., Verticillium spp., Saccharomyces cerevisae MKY3, Phoma spp. etc. have been exploited for the synthesis of different nanoparticles. Among all biological systems, fungi have been found to be more efficient system for synthesis of metal nanoparticles as they are easy to grow, produce more biomass and secret many enzymes. We proposed the term myconanotechnology (myco = fungi, nanotechnology = the creation and exploitation of materials in the size range of 1–100 nm). Myconanotechnology is the interface between mycology and nanotechnology, and is an exciting new applied interdisciplinary science that may have considerable potential, partly due to the wide range and diversity of fungi.
Nanotechnology is the promising tool to improve agricultural productivity though delivery of genes and drug molecules to target sites at cellular levels, genetic improvement, and nano-array based gene-technologies for gene expressions in plants and also use of nanoparticles-based gene transfer for breeding of varieties resistant to different pathogens and pests. The nanoparticles like copper (Cu), silver (Ag), titanium (Ti) and chitosan have shown their potential as novel antimicrobials for the management of pathogenic microorganisms affecting agricultural crops. Different experiments confirmed that fungal hyphae and conidial germination of pathogenic fungi are significantly inhibited by copper nanoparticles. The nanotechnologies can be used for the disease detection and also for its management. The progress in development of nano-herbicides, nano-fungicides and nano-pesticides will open up new avenues in the field of management of plant pathogens. The use of different nanoparticles in agriculture will increase productivity of crop. It is the necessity of time to use nanotechnology in agriculture with extensive experimental trials. However, there are challenges particularly the toxicity, which is not a big issue as compared to fungicides and pesticides.
-
Susceptibility of stem infected sweet corn hybrids to common smut disease
55-57Views:911The common smut of maize (corn smut, Ustilago maydis /DC/ Corda) can cause large economic losses in susceptible sweet corn hybrids as well. The protection against this pathogen is fundamentally based on prevention. Many methods to control corn smut have been recommended or evaluated, including crop rotation, sanitation, seed treatments, modification of fertility, and biological control. In spite of these frequently mentioned control strategies, the host resistance seems to be the only effective method to manage common smut in those areas where Ustilago maydis is prevalent.
-
Fusarium culmorum isolated from rhizosphere of wooly cupgrass (Eriochloa villosa) in Debrecen (East Hungary)
93-96Views:292Wooly cupgrass (Eriochloa villosa) is an East-Asian originated weed species and it has been spreaded worldwide by now. The first occurrence of this species in Hungary was observed and published in 2008 nearby Gesztely village (Borsod-Abaúj-Zemplén county, North-East Hungary) than in the summer of 2011 a significant population was discovered next to Debrecen city (Hajdú-Bihar county, East Hungary).
In 2013 this weed was also reported from Szentborbás village, Somogy county (South-West Hungary). These observations of spreading and its biological features (production of stolons and large number of seeds, moreover herbicide tolerance) indicate that wooly cupgrass (E. villosa) has a great potential of invasiveness, so it may become a hazardous weed not only in Hungary but in all over the world.
The objective of this study was to identify the fungus which was isolated from wooly cupgrass (E. villosa) root residue samples which were collected after maize harvesting on arable land in late autumn, near Debrecen. The identification of the fungus based on morphological characters of colonies and the features of conidia developed on potato dextrose agar (PDA) plates. After the examination of axenic culture we revealed that the fungus from rhizosphere of wooly cupgrass was Fusarium culmorum. Pathogenicity and/or endophytic relationship between the fungus and wooly cupgrass is still uncertain so pathogenicity tests and reisolations from plants are in progress.
-
Potential use of bamboo in the phytoremediation in of heavy metals: A review
91-97Views:911There are many literature sources focusing on the phytoremediation of woody plants, but there are only few dealing with the phytoremediation of bamboo plants. Phytoremediation technology has the advantages of little disturbance to the environment and low remediation cost. Bamboo mainly exists in tropical and subtropical regions. As an energy plant, bamboo has a fast growth cycle, large biomass, simple cultivation, high economic efficiency, and convenient harvesting, which highlights the advantages of bamboo in phytoremediation. In addition, bamboo plants have good tolerance and uptake ability to heavy metals and have high application potential and development value in uptaking heavy metal contaminated soil. However, due to climate, temperature and other reasons, bamboo cannot be widely planted in most countries. Research status of remediation of heavy metal contaminated soil by bamboo plants is summarized. The feasibility of its application in heavy metal contaminated soil is discussed in this paper. Aiming at the shortcomings of existing research, bamboo plants have a prospect in the field of plant phytoremediation for the future.
-
Slight damage of the great green bush-cricket (Tettigonia viridissima) (Orthoptera: Tettigoniidae) in some Hungarian maize fields
65-70Views:440Characteristic cricket damage was observed in two maize fields in northern Hungary, at Máriabesnyő, a district of Gödöllő. The damage level of the two fields did not differ significantly and continual monitoring of field1 showed also a stable infestation level. T. viridissima nymphs and a female were found and observed as feeding on maize plants. The crickets must have disappeared after 18.07. because no more fresh damage was observed after this date. The chewing’s number about on one and two % of the examined plants amounted one and six a plant and their size was between one and eight cm2. This infestation was quite little and might have caused apparently no yield loss. Compared this damage of T. viridissima with former Hungarian experience, this was the usual negligible damage despite the explicit draught in July and August 2015. As regards the global warming, orthopteran damage may be more obvious in the future.
-
Investigation of harvest index influencing agrotechnical and botanical factors in hairy vetch (Vicia villosa Roth.)
123-128Views:493The biggest problem of Hungarian crop farming is mass production and the simple crop rotation based on cereals. There was a decrease in sowing area of protein crops which raises crucial issues in crop rotation and land use. Therefore, growing papilionaceous plants, which are now considered to be alternative plants, should be taken under close examination. Hairy vetch (Vicia villosa Roth.) belongs to the family of papilionaceous plants and it can be grown in light weak soils.
In Hungary, hairy vetch was used as green forage at first, but it later became a green manure plant. Nowadays, it is used as a cover crop and its sowing seed has a good export market. In low fertile soils it is able to produce a big amount of green yield (25–40 t ha-1) even in spring while its seed yield could be 0.4–0.5 t ha-1 at farm level. In addition to its morphological characteristics hairy vetch is grown mainly with a supporting plant, i.e. triticale in many cases.
Our purpose was to test the harvest index and its agrotechnical and botanical factors of hairy vetch in different cropping systems.
-
Impact possibility of hedgerows on plant protection and on the yield of winter wheat
95-101Views:299Agricultural hedgerows have various impacts on the surrounding cultivated area and on the landscape. They serve as a windbreak, help manage humidity and precipitation, and are also sources of plant species richness which can contribute to the animal biodiversity. One of their beneficial effects is the yield improvement of agricultural crops. Our investigation tries to prove this hypothesis in Hungarian circumstances in the case of several winter wheat fields near Debrecen. Regarding the results, it seems that the majority of data supports the relevant, mainly German and Austrian information, but in some cases, the correlation has not been significant.
-
The examination of the agronomy, the amount of yield, and the yield stability of winter wheat varieties
61-72Views:237Our research was carried out at University of Debrecen Centre for Agricultural Sciences Faculty of Agriculture Institution of Plant Sciences Látókép Research Institute through the breeding year of 2003/2004, 2004/2005 and 2005/2006 using cherrnozem soil. In our research we tested 14 chosen autumn wheat varieties during the three crop years.
The different varieties showed very dissimilar ability of resistance against diseases through the three crop years. We could observe both susceptible and resistant varieties. Susceptible varieties got diseases even in favourable crop years. The observed winter wheat varieties showed higher susceptibility against helminthosporium (21.8%) and leaf rost (16.4%). Among the 14 varieties we experienced the least susceptibility in the case of ‘Gaspard’ and ‘GK Kalász’. The research showed that the disease of fusarium undoubtedly depends on the features of the crop year.
In terms of stem solidity we experienced big differences. Among all the observed winter wheat varieties the mid-late ripening ‘Gaspard’ showed the best results in the average of the three years, only 5.3% was beaten down.
The three ripening group of the winter wheat showed the following average yield in the average of three years: 7065 kg/hectare (early ripening varieties), 7261 kg/hectare (late ripening varieties), 6793 kg/hectare (mid-late ripening varieties). Among all the observed varieties the early ripening ‘Flori 2’ produced the biggest yield (7692 kg/hectare).
During the three crop years we reached very different amounts of yield which means that weather conditions had a telling affect on yield. In 2004 we reached an excellent average yield in all the tree breeding groups because of the favourable weather conditions. In 2005 we had a moderate amount of yield because of the unfavourable weather conditions of winter. The year of 2006 showed the smallest amount of yield which is due to the fact that the plant grew less thick than usually.
There were significant differences among the observed varieties in the term of yield, which can be attributed to dissimilar biological basics.
One of he most important questions is the yield stability of the varieties. We had extremely different results at this field. Speaking in general terms we can state that both weather conditions and genetical abilities have a determining effect on yield. In the case of winter wheat varieties the rate of yield fluctuation was quite big, moving in the interval of 33.7-70.3%. Among all the observed varieties ‘Gaspard’ showed the best yield stability (33.3%). -
Describing Fusarium diseases on maize in 2013 using data from several production sites
60-64Views:472As in other parts of the world, the frequency of weather extremes has increased greatly in Hungary in recent years. This means that maize production is faced with greater risks from all aspects: nutrient replacement, irrigation, plant protection. This is especially true of fusarium diseases. In a continental climate, the pathogens causing the most serious problems are species belonging to the Fusarium genus. They infect the ears, which – besides reducing the yield – poses considerable risk to both human and animal health due to the mycotoxins produced by them. Depending on which Fusarium species are dominant at a given location, changes can be expected in the level of infection and in the quality deterioration caused by the mycotoxins they produce. Fusarium spp. not only damages the maize ears but when 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. The degree of infection is fundamentally determined by the resistance traits of the maize hybrids, but also a great role in that region Fusarium species composition as well.
-
Mass occurrence of a Phoma-like fungus on common ragweed (Ambrosia artemisiifolia) in Hajdúság region, East Hungary
55-60Views:427Common ragweed (Ambrosia artemisiifolia L.) is one of the most important, allergenic weed species in Hungary. A. artemisiifolia invades both a broad range of often disturbed areas (brownfields) and either undisturbed ones like waste lands, roadsides, riverbanks and railway tracks. In field crops it can cause considerable yield losses mainly in sunflower, maize, cereals and soybean. In Hungary many inhabitants suffer from allergy caused by Ambrosia pollen which results a serious human-health risk. The aim of the control is to prevent flowering and seed propagation of A. artemisiifolia. Until now the occurrence of numerous pathogenic fungi which attack common ragweed plants have been identified in Hungary, however there is not yet available biological weed control program because of shortage in acceptable effectiveness, and endangering cultural plant species. During our weed surveys in the region of Hajdúság (East-Hungary) we found numerous common ragweed plants showing heavy necrotic lesions on leaves and stems. The objective of this study was to identify the fungus which was isolated from diseased tissues of common ragweed (A. artemisiifolia). The identification of fungus based on morphological characters of colonies and features of conidia and chlamydospores developed on malt extract agar (MEA) plates. After examination of axenic cultures we revealed that the fungus isolated from the leaves ands stems of common ragweed was a Phoma-like species.
-
Agronomical and Economic Evaluation of Different Soil Cultivation Systems
255-258Views:185In the interest of profitable plant production and environmental protection we have to make an effort to protect and improve the productivity of our soils while moderating production limiting factors. Due to different soil cultivation methods, the quantity of yield and required expenses also differ.
We examined the production costs in four different production technology systems. Overall, it can be said that farming standards are good, since cost prices were low (2001: 14-15 HUF/kg, 2002: 15-21 HUF/kg, 2003: 39-49 HUF/kg) in the case of all main products per 1 kg. Cost prices were lowest in the case of direct sowing, probably due to low machinery costs.
All economic indicators have to be compared when choosing the most suitable production technology in a specific farming environment. -
Effect of two different cropyear and the agrotechnological factors on the agronomic characteristic of the winter weat in a lon-term experiment
143-149Views:375We studied the effects of crop rotation, fertilization and crop protection technologies on occurence of the major ear- and leaf-diseases (powdery mildew, helminthosporiosis, leaf rust, Fusarium wilt) and the degree of lodging in the winter wheat variety Mv Pálma in two very different years (2006/2007=dry; 2009/2010=rainy). The experiments were carried out at the Látókép Experimental Farm of the University of Debrecen CAAES in triculture (pea-wheat-maize) and biculture (wheat-maize) at five fertilization levels by applying three different crop protection technologies (extensive, average, intensive).
In the cropyear of 2006/2007, the disease severity of leaf diseases was higher than the average in both crop rotations in spite of the fact that the weather during the whole vegetation period was dry. Infection by powdery mildew, helminthosporiosis and leaf rust increased with increasing fertilization, the highest infection was measured at the highest fertilization level (N200+PK) in the extensive crop protection technology. According to the results, no infection of ears by Fusarium and no lodging occurred in either bi- or triculture due to the dry year. The extremely rainy weather in 2009/2010 was favourable not only for the vegetative development of the stand, but also increased the occurance of leaf-, stalk- and ear-diseases and a high degree of lodging was observed. The highest infection by powdery mildew was observed in the plots with the highest fertilizer dosage under an extensive crop protection technology. A much higher helminthosporiosis infection was measured than in the cropyear of 2006/2007. The wet weather and higher than average temperature promoted the occurence and spreading of leaf rust. Under an extensive crop protection technology, a leaf rust infection of 24% and 31% was detected after maize and pea as a forecrop, respectively, in the N200+PK treatment. As opposed to 2006/2007, the disease severity of Fusarium was 3–8% and 2–7% in the control after maize and pea as a forecrop, respectively. This value, similarly to that of other pathogens, increased with increasing fertilization levels. Due to the large vegetative mass, a significant lodging was observed in the wheat stands in both bi- and triculture (17–100%, 12–100%). -
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. -
Examination of different fungicides against Macrophomina phaseolina in laboratory conditions
65-69Views:383In Hungary, sunflower is the third most important arable crop, which has a lot of pathogenic fungi. One of these fungi is the Macrophomina phaseolina, which is a well-known fungus in all over the world, since this pathogen has more than 700 host plants. In Hungary, several host plants can be found as well. The M. phaseolina produces microsclerotia, which can survive in the soil and residues for almost 10 years. For now, there is no efficient treatment against this pathogen because of this fungus, since it is extremely resistant and cannot be destroyed easily. The only effective treatment against the fungus is genetic defence. In this study, three different fungicides were tested in vitro against the fungus. The Mirage (prochloraz) seemed to be the most effective fungicide as it completely arrested the hyphal growth. In contrast, the Amistar Xtra (azoxystrobin and ciprochonazol) has only a minor effect on the growth of M. phaseolina. Thirdly, the Retengo (pyrachlostrobin) arrested the hyhpal growth of the fungus with 71% at 100 ppm, in other words, the use of this fungicide seems promising.
-
Effect of Irrigation on Maize Yield (Zea mays L.)
30-35Views:934We have been continually examining the fertilizer and irrigation reaction of commonly cultivated maize hybrids for nearly twenty years at the Látókép experimental station of the Center for Agricultural Sciences, Debrecen University.
Upon evaluating the results, it can be established that year significantly influences the size of yield. Between the years of 1999 and 2002, in the average of applied fertilizers the difference is 3,4 t/ha, but even in irrigated treatments it reaches 3 t/ha. This is more than the effect of irrigation. Of the applied agrotechnical elements, the yield increasing effect of fertilization is the greatest and can even be greater than the effect of year. The yield increasing effect of fertilization can be reliably detected with small and medium doses, but at higher doses a plateau section is reached, where it is not worth applying more nutrients. Cultivation with irrigation can only be done with appropriate nutrient supply, due to the positive correlation of the two factors. The positive correlation also means that if the water supply of the plant declines, less fertilizer is needed for safe production. The two factors (irrigation and fertilization) have to be increased or decreased at the same time.
According to the experiment, in unirrigated treatments, 90 kg/ha nitrogen and the related phosphorus and potassium are enough, while in irrigated treatments this was 120 kg. -
Qualitative detection of genetically modified organisms in plant samples
309-313Views:623We analysed the GMO content of corn samples by polymerase chain reaction following the appropriate optimization of the reaction. The analysis included two main steps: extraction of DNA from the sample, and detection of the GMO content by polymerase chain reaction. The polymerase chain reaction is an in vitro method to multiply chromosomatic or cloned DNA (cDNA) sequences through the enzymatic pathway. The reaction is sensitive enough to produce DNA in sufficient amount for the analysis from a single DNA. We identified the PCR products by agarose gel electrophoresis. When optimizing the reaction, the MgCl2 concentration, reaction time and temperature have to be taken into consideration. The temperature of the anellation has to be increased until the highest specificity and yield is reached. If the temperature of the anellation is too high, the primer is linked to non-specific sites as well; in the gel visualization, more lines can be seen at one sample. If the temperature of the anellation is too high, the primer is insufficiently linked or is not linked at all (too few lines in the gel visualization). After optimization, the GMO content in the unknown sample can be determined along with the appropriate positive and negative controls.
-
Activity of some enzymes, participating in nitrogen compounds transformation in chernozem, polluted by fluorine compounds
99-104Views:227Contamination of chernozem by fluorine compounds variously affects those enzymes (urease, asparaginase, glutaminase, arginase, amidase), which takes part in the metabolism of nitrogen-bearing organic compounds. In broken soils the inhibited desaminisations is stronger, than enzymatic hydrolysis of asparagine and arginine. The features of seasonal dynamics of change activity of urease and correlation dependence of its activity from some physical and chemical soils properties are described. These tendencies well comport with the results of model experiments. At minimum HF influence there is inhibition of processes of monohydrocarboxylic acids desaminisation, hydrolytic breaking up of arginine and glutamine. By a side with this there is activating of urea and asparagine breaking up processes on the initial stages of toxicant influence. The study of kinetics of process of urea enzymatic hydrolysis in chernozem at the different level of HF influence showed changes of initial and maximal velocity of enzymatic reaction, and also Michaelis-Menten constant.