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  • Influencing the growth kinetics of yeast strains with vitamin supplementation
    113-115
    Views:
    293

    The aim of the current experiment was to optimize the creation process of single cell protein on plant-based substrate solution with the intention to improve end-product turn out by means of adding vitamin solution. Based on the results of the fermentation processes of yeast strains, it was concluded that the vitamin-supplementation produced its greatest effect on the dry matter production, primarily on the K. marxianus DSM 4908 strain, while it was less beneficent when it comes to the figures of wet cell mass. In addition, it can be assumed that vitamin supplementation increased the maximum specific rate of growth (μmax) and decreased the generation time (tg) significantly. In the case of the K. marxianus yeast strain on corn steep liquor treated with vitamin-supplementation, the highest (μmax) and the lowest (tg) data were observed [(0.226 h-1) and (4.4 h), respectively]. Based on the results it was found that K. marxianus DSM 4908 is expedient to be applied on corn steep liquor medium in order to determine its suitability to produce additive for feeding.

  • Economics of site specific crop density in precision sunflower (Helianthus annuus L.) production
    91-96
    Views:
    455

    In this research, the crop density of sunflower was examined, which, thanks to the tools available for precision crop production and knowledge of the market environment of sunflower production, best fits the heterogeneous areas of the given production zones and meets the economic requirements. These components together directly influence the effectiveness of sunflower production. In the year of 2021 and 2022, we carried out a site-specific crop density sunflower experiment in two fields with the same soil type, by sowing significantly different amounts of seeds within the given zones. We have established that the sunflower, although a plant with excellent adaptability, reacts sensitively to the place of production and the effect of the year, in zones with heterogeneous productivity, and shows a reaction to sowing with a variable number of seeds per zone, even when examined based on economic aspects.

  • Effects of Site on Winter Wheat Quality 2002/2003
    100-107
    Views:
    438

    The demand of modern societies for high food quality is evident. Thus, it is important for agriculture to produce row materials that are valuable for nutrition and have favourable characteristics for food processing. For this we need a knowledge about the factors which determine the quality of products. One of the main features of plant production is the “immobility”. This way the characteristics of the field influence the quality of the product, like example winter wheat, which is the main cereal in Hungary and Europe.
    The Concordia Co. has charged the Central Laboratory of Debrecen University, Agricultural Centre with laboratory testing of the 2002/2003 winter wheat crop. The samples consist of thirteen winter wheat varieties from six different sites under the same cultivating conditions. Therefore, the important wheat quality factors were analysed solely against site conditions with the use of Győri’s “Z” index, which contains these parameters.
    Soils were tested first. In this experiment excepting the negligible differences between the sites, there were no linear relations found between quality factors, productivity and soil features. The case is the same with the relation between precipitation, temperature and quality parameters. However, it must be noted that additional soil analyses are required to interpret the extreme results obtained from Karcag.
    The calculated Győri’s Z-index shows relative stability concerning certain varieties, although considerable deviation can be found in varieties related to the sites. According to these results, it can bestated that winter wheat quality was not linearly influenced by soil and weather in the 2002/2003 vegetation period. As the same cultivation technology was used in the experiment, the index was determined by genetic features. It must be noted that these findings are relevant only to this experiment.

  • Effects of cultivation methods on some soil biological parameters of a meadow chernozem soil (Vertisols)
    61-66
    Views:
    172

    The effect of extended drought conditions on soil, the unfavourable cultivation technologies and the application of chemicals have been enhancing the processes of physical and biological soil degradation, so the fertility of soil is gradually declining. 
    The effects of two cultivation methods – traditional ploughing (TP) and conservation tillage (CT) – on the biological activity of a meadow
    chernozem soil were examined in a long term experiment. Different parameters of the biological activity of soil were determined. These are
    the numbers of total bacteria, microscopic fungi, aerobic cellulose decomposing bacteria, as well as the activities of some important soil
    enzymes and CO2 production.
    Conservation tillage seemed to be a more favourable cultivation method for the majority of microorganisms, the activities of urease and
    dehydrogenase enzymes and CO2 production, compared to the traditional ploughing system. These parameters increased significantly,
    especially in the upper layer of conservation tillage plots. Concerning the plant cultures, the majority of microbiological parameters were
    higher in the soil of vetch (Vicia sativa L.) depending on the cultivation methods, so involving the pulses to the crop-rotation seems to be
    very important in this soil type.
    According to the ninth year’s results, the importance of conservation tillage as a means of protecting the soil biological activity in meadow
    chernozem (Vertisols) can be established; it was proven by microbiological investigations.

  • Study on distribution and relative abundance of click beetle pests (Elateridae: Agriotes sp.) in Hungarian maize fields
    107-113
    Views:
    301

    Click beetle pests (Elateridae: Agriotes sp.) of 24 sites in different regions of Hungary were studied in 2011. A. brevis, A. sputator, A.
    obscurus, A. lineatus, A. rufipalpis and A. ustulatus were sampled by pheromone traps in maize fields. During the study 65895 beetles were
    caught. A. ustulatus and A. sputator were the most abundant species. Beyond that 23 additional species were trapped so the total number of sampled species was 29. The distribution of the six studied species was uneven. In east Hungary A. ustulatus were the most abundant, while
    in the Transdanubia A. sputator was dominant in the most studied sites. A. obscurus occurred mostly in Transdanubia (western Hungary), and it occurred only in one site of eastern Hungary. 
    The abundance of one or simultaneously two species reached the threshold of significant damage in 14 sites. Additionally there were three sites where the total abundance of the two most dominant species reached the threshold. There were only six sites where we should not expect significant damage. In this reason we have to monitor the populations of these pests and if it is necessary we have to take actions against them.

  • The role of leaf area and photosynthesis in optimising the sowing date of maize
    5-10
    Views:
    423

     

    Our sowing date experiment took place in the Demonstration Garden of Institution of Plant Sciences, Agricultural Center of University of Debrecen, in 2012–2014. The thesis contains data of test year 2014. Our purpose, besides several other examinations, was to observe how sowing date influences leaf area index and activity of photosynthesis of maize hybrids, and how those factors affect fruiting. In the experiment we monitored the change of the leaf area index and the photosynthesis of hybrids with four different growing seasons.

    Based on the results, it can be concluded that most of the examined hybrids reached their smallest leaf area with the third sowing date and with the highest yield results. Hybrid Da Sonka had the largest leaf area (4.10 m2 m-2), and hybrid DKC 4590 produced the highest yield (13.16 t ha-1)

    with the third sowing date.

    During testing the photosynthetic capacity, the extremely high performance of the youngest plants with the third sowing date is outstanding, which can be explained by the different ripening periods. Examination of the correlation between the photosynthetic capacity and the yield, by linear regression analysis, also proves that photosynthesis has a determinative role in fruiting.

    The results obtained confirm that not only the environmental and agricultural factors in the growing season have effect on the yield, but also other factors like the leaf area index and the photosynthesis are determinative parameters, and all those factors together, modifying effects of each other, develop average yields.

  • Changes of some soil chemical and microbiological characteristics in a long-term fertilization experiment in Hungary
    253-265
    Views:
    652

    Agricultural management practices – directly or indirectly – influence soil properties.

    Fertilization rates and crop rotation can strongly affect soil pH, soil nutrient supply and soil organic matter content due to the changes of microbial processes. The objective of this study was to compare the effects of different fertilization doses in monoculture and tri-culture of maize (monoculture: only maize grown since 1983, tri-culture: it is a three-year crop rotation system: pea – winter wheat – maize) on selected soil characteristics. The long-term fertilization experiments were set up in 1983 in Eastern Hungary. These experiments are situated west of Debrecen in Hajdúság loess region, on calcareous chernozem (according to WRB: Chernozems).

    The test plant was maize (Zea mays L.). One-one pilot blocks were selected from monoculture and tri-culture of the long-term experiments. The observed soil samples were taken in the 30th year of the experiment, in 2013. The doses of NPK fertilizers increased parallel together, so the effects of N-, P- and K-fertilizers cannot be separated.

    With the increasing fertilizer doses, the soil pH has decreased in both crop production systems and, in parallel, the hydrolytic acidity has significantly increased. A close negative correlation was proved between the pHH2O, pHKCl and hydrolytic acidity. An increased nutrient content in soil was recorded in every NPK treatment and the available phosphorus and nitrate content increased in higher proportion than that of potassium. Of the measured parameters of C-and N-cycles, fertilization has mostly had a positive effect on the microbial activity of soils. Besides the effects of fertilizer doses, correlation were looked for between soil microbiological properties. Evaluating the ratios among the measured parameters (organic carbon and microbial biomass carbon, OC/MBC ratio; carbon-dioxide and microbial biomass carbon; CO2/MBC proportion), the fertilization rate seems to be favoured by the increase of amounts of organic compounds

  • Agronomical and Economic Evaluation of Different Soil Cultivation Systems
    255-258
    Views:
    185

    In 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
    143-149
    Views:
    375

    We 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
    83-86
    Views:
    332

    In 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.

  • Mass occurrence of a Phoma-like fungus on common ragweed (Ambrosia artemisiifolia) in Hajdúság region, East Hungary
    55-60
    Views:
    427

    Common 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.

  • Examination of different fungicides against Macrophomina phaseolina in laboratory conditions
    65-69
    Views:
    383

    In 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.)
    30-35
    Views:
    934

    We 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
    309-313
    Views:
    623

    We 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
    99-104
    Views:
    227

    Contamination 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. 

  • Comparative examination of the tillage systems of maize on meadow chernozem soil
    21-24
    Views:
    439

    Maize production plays a major role in the agriculture of Hungary. Maize yields were very variable in Hungary in the last few decades. Unpredictable purchase prices, periodical overproduction, the increasing occurrence of weather extremities, the uncertain profit producing ability, the soil degradation processes (physical, chemical and biological degradation) and the high expenses are risk factors for producers. Due soil tillage, there is an opportunity to reduce these risks. Based on the experimental database of the Institute of Land Utilisation, Regional Development and Technology of the University of Debrecen, Centre for Agricultural and the KITE Plc., various cultivation systems were examined with maize (Zea mays L.) as indicator plant in Jász-Nagykun-Szolnok country in 2012 and 2013. The sample area can be found in the outskirts of Kenderes on a meadow chernozem soil. On the examined plot, strip-tillage, subsoiling and moldboard ploughing were performed, each on 4.5 ha, respectively.

    In general, our findings show, that strip-tillage and subsoiling can be alternative tillage systems beside moldboard ploughing on meadow chernozem soils in Hungary.

  • Let's talk about 'One fungus One name'. Changes in the fungal taxonomy
    11-14
    Views:
    459

    Mycologists have recorded a few hundred thousand Latin names for fungi and these are thought to refer to 70 000 or so separate species. The use of molecular techniques in fungal taxonomy and systematics in the last 25 years has provided massive amounts of information to clarify phylogenetic relationships, encouraged grant support, and complicated the jobs of classically-trained mycologists. Taxonomists have a reputation for being traditionalists, but the community has recently embraced the modernization of the nomenclatural rules by discarding the requirement for Latin descriptions, endorsing electronic publication, and ending the dual system of nomenclature, viz. teleomorph and anamorph names, which used parallel for the sexual and asexual phases of pleomorphic species. A group of taxonomists accepted ’The Amsterdam Declaration on Fungal Nomenclature’ and its basic principle the ’One fungus – one name’ has been incorporated in the Code of Nomenclature (’Melbourne Code’) in 2011. The next, and more difficult step will be to develop community standards for sequence-based classification. As the’One fungus – One name’ theory is a brand-new issue for the Hungarian plant doctors and practical specialists, it seems reasonable to review this to promote conversations between generations in Hungarian language.

  • Examination of nutrient reaction of winter wheat after sunflower forecrop
    9-13
    Views:
    275

    We tested the fertilizer reaction of four different winter wheat varieties in three different crop years, on chernozem soil, in long-term experiment. We examined the optimum fertilizer requirements and the maximum yield of the varieties. According to our results there were significant differences among the years: the yield of the winter wheat varieties changed between 1.4–6.1 t ha-1 in 2013, 3.8–8.6 t ha-1 in 2014 and 3.2–8.6 t ha-1 in 2015. The yield increasing effect of fertilization was significantly different in the tested years. The optimum level of fertilization was determined by, besides the genetic differences among the varieties, the crop year and the extent of fertilization. In milder winter months, due to the higher average temperatures, yields of winter wheat increased compared to an average crop year.