Search

Published After
Published Before

Search Results

  • Growth and clorophyll content dynamics of winter wheat (Triticum aestivum L.) in different cropyear
    101-105
    Views:
    107

    The experiments were carried out at the Látókép experimental station of the University of Debrecen on chernozem soil in a long term winter wheat experiment in the season of 2011 and 2012 in triculture (pea-wheat-maize) and biculture (wheat-maize) at three fertilisation levels (control, N50+P35K40, N150+P105K120). Two different cropyears were compared (2011 and 2012).

    The research focused on the effects of forecrop and fertilisation on the Leaf Area Index, SPAD values and the amount of yield in two different cropyears. We wanted to find out how the examined parameters were affected by the cropyear and what the relationship was between these two parameters and the changes of the amount of yield.

    Examining the effects of growing doses of fertilizers applied, results showed that yields increased significantly in both rotations until the N150+PK level in 2011 and 2012. By comparing the two years, results show that in 2011 there was a greater difference in yields between the rotations (7742 kg ha-1 at N150+PK in the biculture and 9830 kg ha-1 at N150+PK in the triculture). Though wheat yields following peas were greater in 2012, results equalized later on at N150+PK levels (8109–8203 kg ha-1).

    Due to the favorable agrotechnical factors, the leaf and the effects of the treatments grown to a great extent in 2011, while in 2012 the differences between treatments were moderate. Until the N150+PK level, nitrogen fertilisation had a notable effect on the maximum amount of SPAD values (59.1 in the case of the biculture and 54.0 in the triculture). The highest SPAD values were measured at the end of May (during the time of flowering and grain filling) in the biculture. In the triculture, showed high SPAD values from the beginning. The same tendency could be observed in the 2012 cropyear, although increasing doses of fertilizers resulted in higher SPAD values until N150+PK level only from the second measurement. Maximum SPAD values were reached at the end of May in both crop rotation system

  • Effect of agrotechnical factors on the activity of urease enzyme in a long term fertlization experiment
    43-48
    Views:
    126

    The soil is a natural resource, the fertility preservation is an important part of the sustainable development. We have to monitor the transformation dinamics of the organic nitrogen-containing substances, to get accurate information about the changes of the nitrogen cycle in the soil.

    Physical and chemical properties of the soil and the microorganism effect on the organic matter in the soil – in addition to the composition of organic matter. Wide variety of extracellular enzymes are present in this decomposition. These enzymes help in the transformation of the macromolecules to transforming low molecular weight compounds so they will be available during the assimilation.

    The urease enzyme, catalyzes the hydrolysis of urea to CO2 and NH3. The urease is widely spread in the nature, it is present in the microorganisms, plants and animals.

    We found that the soil moisture content, the rotation and the fertilization affect to the amount of urease in spring. Furthermore, we get significant difference between the irrigated and non irrigated samples in the second period of the year. Based on our results we can state that the activity of urease was higher in spring 2014.

    The objective of our study was to present how the different agronomic factors affect on the activity of urease in a long term fertilizationexperiment.

  • The irrigation influence under the soil, microclimate and plants in maize from Crişurilor Plain
    180-186
    Views:
    71

    The paper is based on the researches carried out in the long term trial placed on the preluvosoil from Oradea in 1976, for establishing
    the soil water balance. In the irrigated variant the soil moisture was determined 10 to 10 days for maintaining the soil water reserve on
    irrigation depth (0 – 50 cm for wheat and bean, 0 – 75cm for maize, sunflower, soybean, sugarbeet, potato and alfalfa 1st year and 0 – 100
    cm for alfalfa 2nd year) between easily available water content and field capacity. Thus, an average irrigation rate of 2560 m³/ha was used
    in the 9 experimental crops. The average of the annual rainfall for the 1976 – 2008 period was of 625.0 mm. The technologies used were
    correlated with the needes of the crops, such as melioration crop rotation, chemical fertilizers in accordance with the chemical export on the
    yield, manure (40 t/ha) was used in potato and sugarbeet. After 33 years of the irrigation use the soil structure degree (38.62%) did not
    decrease when compared to the unirrigated maize – wheat crop rotation (37.01%). Bulk density, total porosity, penetration resistance and
    hydraulic conductivity have worse values than the ones in the unirrigated variant. The humus content is very close to the humus content
    determined in 1976, the phosphorus and the potassium content increased very much in comparison with the initial content (117 ppm vs 22.0
    ppm); (180.0 ppm vs 102 ppm). The use of the adequate fertilization system and of the irrigation water with a good qaulity did not determine
    a decrease of the pH value of the soil. The irrigation determined the improve of the microclimate conditions, the increase of the plant water
    consumption, yield gains very significant statistically and higher protein content of the maize grains.

  • Correlations of the growth indexes and yield of winter wheat in a long-term experiment
    139-144
    Views:
    135

    The experiments were carried out at the Látókép experimental station of the Centre for Agricultural Sciences of University of Debrecen on chernozem soil in a long term winter wheat experiment. As forecrop rotation, we set up two models: a biculture (wheat and corn) and a triculture (pea, wheat and corn). We applied three levels of nutrients during the fertilization process (control, N50P35K40 and N150P105K120). The third variable studied was irrigation in case of which we tested non-irrigated variables (Ö1) and irrigation variables complemented up to the optimum (Ö3).

    The effect of pre-crops, irrigation and nutrient-supply levels on some growth-parameters (LAI, LAD), weight of dry matter, just as SPADvalues and yield amounts of winter wheat has been investigated in this experiment. We tried to find out the extent of relationship between the different parameters, and we used the correlation analysis. The correlation analyses have confirmed that all of the investigated parameters had almost in all cases close positive correlation to the yield amount. These results have confirmed that the leaf area, the leaf duration, the SPADvalues, the fertilization and the forecrop have altogether resulted in the production of maximum grain yields.