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  • Phytopatological properties of symbiotic Rhizoctonia solani strains associated to orchids
    65-71
    Views:
    312

    The 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 In general, we can assume that orchid associated Rhizoctonia strains are potential plant pathogens, and removed or withdrawn orchid stools should be treated as hazardous waste.

  • Rheological evaluation of industrial tomato
    137-140
    Views:
    326

    Today, tomato has the second largest harvesting area globally, and the fourth largest in Hungary. The importance of industrial tomato is growing year by year, and one of the most important tasks is to satisfy the needs of the industry. To meet these needs, the producer has to find the proper genotype, which can achieve up to 100 t ha-1 crop yield. This quality has high importance to be researched.

    The experiment was carried out in the Botanical and Exhibition Garden of the University of Debrecen, with 3 examined genotypes. The planting date was 3 of May 2018. The harvesting was two-threaded. On 27 of July the physical parameters – fruit shape index (length/diameter), firmness (kg cm-2), water-soluble dry matter content (Brix%) and weight of the berries (g) – were evaluated. On 15 of August the rheological parameters were examined – the force needed to tear the skin – bioyield point (g) and flesh firmness (g).

    The fruit shape index was oval (between 1.19 and 1.24) for all the examined genotypes. The firmness was between 0.92 (UG1122713 F1) and 1.05(Prestomech F1) kg cm-2, which compliance the needs of the industry. The water-soluble dry matter content was suitable, with a value between 4.49 (Prestomech F1) and 4.65 (UG1122713 F1) Brix%. The weight of the berries was between 45.94 (UG989 F1) and 49.37 (Prestomech F1) g per piece.

    The bioyield point was between 76.00 (UG1122713 F1) and 85.16 (UG989 F1) g. The flesh firmness was between 33.68 (UG1122713 F1) and 42.81 (UG989 F1) g.

    Finally, we can conclude based on the obtained data that the UG989 F1 hybrid was the most proper for the applied cultivation conditions. This genotype can be recommended for the farmers even in extreme weather conditions.

  • Evaluation some important microbiological parameters of the carbon cycle in chernozem soils profiles
    33-39
    Views:
    440

    Some chemical and microbiological properties of the carbon cycle were investigated in three chernozem soil profiles. The soil profiles originated from a long term fertilization experiment (potato) of the University of Debrecen, Látókép, Kryvyi Rig Botanic Garden (grassland) and a large-scale farm (sunflower) of Ukraine. The results of the organic C-content, total number of bacteria, microscopical fungi, cellulose decomposing bacteria, CO2-production, microbial biomass carbon and saccharase and dehydrogenase activities were compared and evaluated with the help of correlation analyses. Close correlation was found between the organic carbon content and the number of microscopical fungi,, saccharase and dehydrogenase enzymes’ activities, as well as close correlation was found between the dehydrogenase activity and microbial biomass-C and saccharase activity.

  • The effect of different herbicide on the number and activity of living microorganisms in soil
    76-82
    Views:
    272

    Sustainable plant growth, considering the difficulties of weed elimination, cannot be effective without the application of herbicides. However, these chemicals have enormous ecological implications, including effects on the microbiological communities of soils. It is advisable to use herbicides that have minimal secondary effects on the environment and soil-living microorganisms. In contrast, herbicides with prolonged growth stimulating or inhibiting effects are not suitable, because both types have strong influences on the number and activity of bacteria, thus causing changes in the ecological equilibrium.
    Preceding small plot experiments, laboratory tests were carried out to study the effect of herbicides used in maize cultures on the number of bacteria and growth of microscopic fungi.
    Substances that were observed to have stronger influences were applied in small plot experiments set up in the experimental garden of the Department of Plant Protection of the University of Debrecen. We studied the effects of four herbicides (Acenit A88EC, Frontier 900 EC, Merlin SC and Wing EC) on the microbiological properties of the soil. These herbicides were used in different concentrations in maize culture, and we investigated the effects in different soil layers.
    In the laboratory experiments, we determined the total number of bacteria and microscopic fungi and examined the growth of Aspergillus niger, Trichoderma sp. and Fusarium oxysporum on peptone-glucose agar containing herbicides.
    During the small plot experiments, soil samples were collected 3 times a year from 2-20 cm depth. The total numbers of bacteria and microscopic fungi were determined by plate dilution method, while the method of most probable number (Pochon method) was used to determine the numbers of nitrifying bacteria and cellulose decomposing bacteria. To evaluate the microbiological activity of the soil samples we measured carbon-dioxide release (after 10 days incubation), nitrate production (after 14 days incubation) and the concentration of C and N in the biomass.
    We can summarize our results as follows:
    • In laboratory experiments, herbicides caused a decrease in the number of bacteria and inhibited the growth of microscopic fungi.
    • Frontier 900 EC and Acenit A 880 EC had the strongest inhibiting effect on microorganisms.
    • In small plot experiments, herbicide treatment decreased the total number of bacteria and microscopic fungi.
    • Herbicides caused a significant increase in the number of nitrifying and cellulose decomposing bacteria.
    • Different herbicides containing the same active compound had similar influences on soil microoorganisms.
    • A significant increase was observed in the physiological processes of tolerant microorganisms surviving the effects of herbicides

  • The significance of biological bases in maize production
    61-65
    Views:
    321

    The comparative trial has been set up in the Demonstration Garden of the Institute of Crop Sciences of the University of Debrecen, Centre for Agricultural and Applied Economic Studies, Faculty of Agricultural and Food Sciences and Environmental Management in 2012, with 24 hybrids with different genetic characteristics and growing periods. The soil of the trial is lime-coated chernozem, with a humus layer of 50–70 cm.

    The weather of the trial year was quite droughty; the monthly average temperature was 3–4 oC higher than the average of 30 years. High temperature, together with lack of precipitation occurred during the most sensitive phenophases of maize (flowering; fecundation, grain saturation).

    The following characteristics have been observed: starting vigour, date of male and female flowering, plant and cob height, dry-down dynamics during maturation and the change of yield composing elements has also been quantified. The yield was recalculated to 14% moisture content grain yield after harvesting.

    The beginning of the growing period was advantageous, therefore the analysed hybrids could grow a high (above 300 cm) and strong stem. The yield of the hybrids changed between 10.33 and 11.87 t ha-1, but as a result of the unfavourable climatic extremes, their genetic yield potential prevailed only at a rate of 30–40%. However, moisture content by the time of harvesting was good despite its early date (12th September); it remained under below 14% in most cases. Dry-down was measured on a weekly basis between 14th August and 5th September.

    The analysis of the qualitative parameters of the maize hybrids (protein %, oil % and starch %) resulted in significant differences. The most significant difference has been observed in the case of protein content (LSD5%=2.01). Oil content was the most advantageous in the case of hybrids belonging to the mid-late growing group (FAO 400). The X9N655 and 36V74 hybrids had the highest oil content (around 4%), while hybrids P9915 and 37F73 had significantly lower oil content. Starch content was above 70% in the case of every hybrid.

    Hybrid selection is highly important in terms of yield and yield security of maize, as well as the application of modern biological fundamentals and hybrid specific technology for the improvement of the level of cultivation technology.

  • Correlation between sowing time of maize hybrids, yield and seed moisture content at harvest on chernozem soil
    32-41
    Views:
    377

    In this paper, we analysed the results of maize sowing time experiments conducted by the Department of Crop Sciences and Applied Ecology of the University of Debrecen Agricultural Sciences Centre, during the period from 1997-1999. We made the experiments at the experimental garden of DE ATC, on a chernozem soil with lime deposits.
    In 1997, we examined five hybrids, in 1998 six hybrids, and in 1999 three hybrids, with three sowing times. Sowing times were early (10. Apr. and 08. Apr.), optimal (25. Apr. and 28. Apr.) and late (15. May and 17. May). 
    We examined the following standards: yield, seed moisture content at harvest, thousand kernel mass, duration of flowering, emergence time and profitability.
    In 1977, the emergence times, in order of sowing, were: 24, 12 and 9 days. Yields of the sowing times were the following, in mean, for the five hybrids: in the early sowing time (10. Apr.) 11,81 t/ha, in the optimal sowing time (25. Apr.) 11,67 t/ha, and in the late sowing time (15. May) 12,9 t/ha. The seed moisture content of the five hybrids at harvest was 8% less in early sowing time, than in the late sowing time. The thousand kernel mass was the biggest in late sowing time, but we could not prove any significant connection attributable to the effect of sowing time. We examined
    profitability, too. Of the five hybrids, four attained the greatest profit with the early sowing time in 1997.
    In 1998, the emergence times, in the order of sowing, were: 21, 10 and 11 days. Yields of the sowing times were the following, in mean, for the six hybrids: 08. Apr. 10,34 t/ha, 25. Apr. 11,02 t/ha, 15. May 11,52 t/ha. There were no significant differences between yields in 1998. The seed moisture content of the six hybrids at harvest was 7% less for the early sowing time, than for the late sowing time. In 1998, the profits were greatest for the
    early and traditional sowing times.
    In 1999, the numbers of days from sowing to emergence were 18, 9 and 9 days, in the order of sowing times. Yields of the sowing times were the following, in mean, for the three hybrids: 13,25  t/ha, 12,51 t/ha and 12,34 t/ha, in the order of sowing times. The seed moisture content of maizes at harvest was 6% less with an early sowing time in the mean of all hybrids. In 1999, hybrid maizes gave big profits with early sowing times.
    Summing up the results of the three years, we can conclude that we get a significant yield increase and reduced seed moisture content at harvest if we apply the early sowing time, which can considerably increase the efficiency of maize cultivation. 

  • Application of mycorrhizae and rhizobacteria inoculations in the cultivation of processing tomato under water shortage
    111-118
    Views:
    453

    The effect of mycorrhizal fungi and plant growth promoting rhizobacteria on some physiological properties, yield and soluble solid content (Brix) of ‘Uno Rosso’ F1 processing tomato was studied under water scarcity. Inoculation was performed with mycorrhizal fungi (M) and rhizobacteria preparation (PH) at sowing (M1, PH1) and sowing + planting (M2, PH2). The treated and untreated plants were grown with regular irrigation (RI = ET100%), with deficit irrigation (DI = ET50%) and without irrigation (I0). In drought, the canopy temperature of plants inoculated with arbuscular mycorrhizal fungi (M1, M2) decreased significantly, however, the decrease was small in those treated with the bacterium (PH1, PH2), while the SPAD value of the leaves of plants treated only with Phylazonit increased significantly. On two occasions, inoculations (M2, PH2) significantly increased the total yield and marketable yield, however, under water deficiency, a higher rate of green yield was detected than untreated plants. In dry year using deficit irrigation, the one-time inoculation (M1, PH1) provided a more favorable Brix value, while the double treatments reduced the Brix. In moderate water scarcity, the use of mycorrhizal inoculation (M2) is preferable, while under weak water stress, the use of rhizobacteria inoculation (PH2) is more favorable.

  • Effect of season and sowing time on the moisture loss dynamics and yield of maize
    255-265
    Views:
    471

    The effect of sowing date on maize development and yield was studied in field experiments. The experiment was set up at the experimental garden of the University of Debrecen Centre of Agricultural Sciences Faculty of Agriculture, Department of Plant Sciences in 2005 and 2006 on calcareous chernozem soil. Six hybrids with different genetic characteristics and vegetation period were tested (Sze 269, DK 440, PR37D25, NK Cisko, Mv Maraton, PR34B97) at three different sowing dates.
    2005 was a very wet year. The amount of precipitation in the vegetation period was about 150 mm higher than the average of 30 years. No significant differences were observed in temperature. However, the number of sunny hours was much lower during the summer than as usual. This had an influence on yields.
    In 2006, there was no risk of inland water in spite of the large amount of precipitation at the beginning of the year. The amount of water available for plants was satisfactory during the season due to the favorable amount of precipitation. Therefore, plants suffered less from the heat in July. However, hail on 22 July caused significant damage. The number of sunny hours in the summer was high enough. The warm, dry autumn helped the water release of plants.
    In 2005, the results of the third sowing date could not be evaluated due to the large number of missing plants. The yield of hybrids ranged between 12-14 t/ha for the first sowing date. For the second sowing date, yields ranged between wider boundaries. The hybrid PR37D25 has a very high yield in the case of the second sowing date, and its seed moisture content was favorably low. The yield of hybrid PR34B97 was the lowest at the later sowing date, the prime reason of this was damage caused by Diabrotica virgifera. The seed moisture content at harvest varied between 16-24% for the first sowing date. In the case of the second sowing date, higher values were measured. Hybrids Sze 269 and NK Cisko had favorable water release characteristics. The maximum value of leaf area index was the best in the case of the first sowing date (5-5.5 m2/m2).
    In 2006, yields for the first sowing date ranged between 8-10 t/ha. At the second sowing date, more favorable results were obtained. The reason for this is probably that hail caused a higher damage in hybrids with the early sowing date. Plant stock with later sowing date could recover more successfully. Hybrid PR37D25 had very high yields for the second and third sowing dates. The high-yielding hybrid PR34B97 also had high yield, but this was accompanied by higher seed moisture content. Due to the warm, sunny autumn weather, the hybrids had good water-release dynamics and were harvested with a lower seed moisture content than in the previous year. For the first sowing date, the seed moisture content was around 13-14% except for hybrid PR34B97. For the second and third sowing dates, higher values were observed. Leaf area index was significantly reduced in August for all three hybrids due to the hail in July. For the first two sowing dates, the leaves of hybrid Sze 269 were the first to dry similarly to the previous year.
    Year had a strong effect on the results in both years.

  • Setting up the operation of a Science Centre using process management tools
    47-55
    Views:
    222

    Nowadays, Science Centres, which have a very long tradition in Europe, are continuously spreading in Hungary. These institutions primarily aim at raising public awareness of science in young people via informal learning (hands-on, minds-on etc.) methods. Based on this phenomenon, the construction of Scientific Adventure Park has been started in the Debrecen Botanical Garden. In addition, the Municipality of Debrecen established a new organization who will be responsible the reaching the defined goals and sustainability of Debrecen Science Centre according to the Application Form. Therefore, it will be designed a new institution with characteristics of Science Centre and provide innovative and complex services in the segments of culture and education. In this paper, I'm searching for answers to the question if based on this process-oriented method and  management approach; it is possible to design operation system capable of achieving the strategic goals mentioned above.