Search

Search Results

• Impact of fertilization on production capacity and reaction to fertilization in maize hybrids

  42-46

  Péter Jakab

  Views:

  67

  New varieties and fertilization have significantly increased yields of maize in recent decades. It has to be taken into account however that the interactions and the balanced combination of cropping factors (ecological, biological and agrotechnical) are the main factors which determine yields. Weather conditions were rather unfavourable during the last decade. Extreme weather conditions occurred due to global warming; 6 of 10 years were plagued by drought. Consequently yields increased from 10-20% to 30-50%. In view of varieties the situation is advantageous, maybe the supply of hybrids is too high, nevertheless those hybrids need to be selected which are particularly well adjusted to the ecological conditions. Many technologies can be applied which vary according to intensity, but the balanced combination of cropping factors should be secured on the basis of the hybrid’s intensity. Among agrotechnical factors the compensation of nutrients and technological conditions were inadequate. These days farmers only use nitrogenous fertilizers consequently they significantly decrease the easily available P and K content of the soil which in long term leads to the deterioration of the soil’s productivity. The technological background is therefore important, because sufficient yields can only be expected if agrotechnical operations are carried out in the right time and quality. 

• The effect of different herbicide on the number and activity of living microorganisms in soil

  76-82

  Zsolt Sándor

  Views:

  119

  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

• Effects of some herbicides on the microbiological characteristics of soil nitrogen cycle under maize plantation

  93-100

  Zsolt Sándor

  Magdolna Tállai

  Views:

  71

  Nitrogen is a key element for the living organisms and influence not only for the quantity but for the quality of the yield, considerable. Availability of nitrogen from the soil is influenced by several microbiological processes of the Nitrogen-cycle. Among the intensive agricultural production the herbicide application cannot be omitted more information needs therefore about the inhibitor effect of herbicides on the different microorganisms.
  An experiment was set up on calcareous chernozem soil under maize culture. Effect of four different herbicides (Acenit, Frontier, Merlin, and Wing) was investigated. The effect of herbicides was measured to four microbiological parameters of the Nitrogencycle (abundance of nitrifying bacteria, nitrate solubilisation, biomass nitrogen and urease enzyme activity). There were singledouble-  and five times of recommended doses of herbicides applied for two onsecutive vegetation periods.
  From the results of the different doses of herbicides, the following can be stated:
  – The Acenit has a stimulating effect on nitrifying bacteria in general. The Frontier and Merlin also influenced the quantity of nitrifyers, however in certain cases decreased in another cases increased the number of bacteria.
  – The double doses and five times doses of herbicides was found to be increasing the nitrate content of soil, -especially in 2006.
  – The quantity of microbial biomass nitrogen increased in the 60% of treatments and decreased in the 40% of the treatments.
  – Except of the result of Wing in 2006 and Merlin in 2005, the effect of simple dose herbicides was the smallest on the urease enzyme activity. According to the results the effect of Merlin was positive; the effect of Wing was negative on the soil enzyme’s activity.
  Regarding the application of four different herbicides in three  different doses on the microbiological parameters of soil (at two consecutive years-) in 39% of the treatments has resulted a significant inhibitory effect, 28% of the treatments, however have significant stimulating effect on the parameters measured. More than 50% of the inhibitory effect was measured in case of the Wing, at more than 50% of the Frontier the microbiological parameters have not changed.

• Comparative analysis of certain soil microbiological characteristics of the carbon cycle

  137-141

  Bence Mátyás

  Judit Horváth

  János Kátai

  Views:

  128

  In our researches, we examine the soil microbial parameters related to the carbon cycle. In this study, we compare the changes of microbial biomass carbon (MBC) and the soil CO₂ production in soil samples which were taken in spring and autumn. The 30 years old long-term experiment of Debrecen-Látókép is continued in our experiments. The long-term fertilization experiment was set in 1983, and our sample was taken in spring 2014. The examinations of soil respiration processes and factors that influence soil respiration are required in optimal management. In our study, we interested to know how the growing levels of fertilization influence the soil respiration and microbial biomass carbon under non-irrigated and irrigated conditions in maize mono, bi, and triculture.

• Agronomical and economic evaluation of various cultivation systems on meadow soil

  103-106

  Sándor Ferencsik

  Views:

  102

  The requirements and objectives of cultivation are in constant change. There are different cultivation aims if the objective is soil protection, the prevention of its moisture content or on areas with different precipitation supply or production site endowments. Based on the experimental database of the Institute for Land Utilisation, Regional Development and Technology of the University of Debrecen, Centre for Agricultural and Applied Economic Sciences and the KITE Plc., the various cultivation systems in Hajdú-Bihar country were examined with maize as indicator plant. The sample area can be found in the outskirts of Biharnagybajom on meadow soil. On the examined plot, spring strip basic cultivation, loosening and autumn ploughing were applied on 15-15-15 ha, respectively. At the time of taking undisturbed soil samples, soil conductivity measurements were also performed with a Penetronik penetrometer. Undisturbed soil samples were taken from each treatment before sowing (on 5th April 2012). The yield obtained in the strip cultivation treatment increased that of the ploughing and the loosening technology. The economic indexes are the most favourable in the strip cultivation.