The rich assortment of maize cultivars available in Hungary as the result of genetic research can only be recommended to crop growers in the full knowledge of their responses to nutritional effects in the given agro-ecological region. The nutrient responses of eight different maize (Zea mays L.) hybrids differing in the duration of the vegetation period (FAO 200-430) were studied in field fertilisation trials conducted in four different agro-ecological regions of Hungary. Four treatments were applied: 1) minimum NPK dose, 2) NPK dose corresponding to the nutrient requirements of maize, 3) NPK dose exceeding the nutrient requirements of maize, 4) farmyard manure (FYM). The NPK contents of the grains were measured in addition to the grain yields. In most cases, a nutrient supply exceeding the demand of the maize plants did not result in significantly higher grain, nitrogen, phosphorus or potassium yields at any of the sites. Compared with the minimum mineral fertiliser dose, FYM did not result in higher grain, nitrogen, phosphorus or potassium yields; in fact, these parameters were significantly lower in some cases. Considerable site and cultivar differences could be detected in the experimental parameters. The nutrient responses discussed here could be of assistance in choosing the most productive hybrids and the optimum range of nutrient supply for the sites involved in the experiments.
The long-term effect of N and P fertilisation on the grain yield, yield components and quality parameters of winter wheat was studied for different sites in the National Long-term Fertilisation Trials in Hungary. This network of small-plot fertilisation experiments has been maintained since 1967 in nine different agro-ecological regions of the country. Increasing P and N doses had a considerable effect on the grain yield, yield components and quality parameters of winter wheat according to the results evaluated in the first 20-year average of the experiments. However, these effects differed depending on the agro-ecological conditions of the sites. Yield increases could be detected at lower fertiliser doses, and improvement in quality parameters at higher rates.
Authors:K. Debreczeni, K. Berecz, K. Fischl, and Z. Wittmann
large-pot model experiments were conducted with maize under greenhouse conditions with the aim of studying the effect of different N fertiliser forms, water supplies and crop residues on the nitrogenous gas production in the rooting zone. Nitrogen fertiliser was applied in the form of KNO3 or NH4Cl. The experiment was done at two soil moisture levels, with or without the incorporation of maize crop residues into the soil, and with or without test plants. Gas traps were placed in the pots at a soil depth of 20 cm. During the growing season, the trapped soil air was analysed for NOx, N2O and N2. Practically the same N amounts evolved in the soil air with both chemical forms of N fertiliser at both soil moisture levels. expressed as a percentage of fertiliser N, the total amount of gaseous N evolved averaged 12.8% and 12.9% in the planted, and 23.8% and 24.3% in the unplanted pots with KNO3 and NH4Cl fertiliser, respectively. Higher soil moisture and the incorporation of crop residues resulted in higher NOx-N and N2O-N ratios within the total gaseous N evolved in the rooting zone.
Authors:Erika Nótás, K. Debreczeni, K. Fischl, and et al.
The primary (1
year) and the after-effects (2
year) of N
Cl) on the soil-plant-atmosphere
system were studied in a three-year greenhouse pot experiment with and without
maize plants. The two- and three-year balances of the fertilizer N uptake and
gaseous N losses were also analyzed. The cumulative values of the gaseous
losses showed a similar trend in all years, significant differences were not
obtained. On the basis of the three-year balance, the gaseous loss in the
planted and unplanted pots was 18-22% and about 37-39%, respectively.
Consequently, there was a 50% decrease in denitrificated gaseous losses of fertilizer
N due to plant N uptake. The cumulative gaseous loss, calculated by the
difference method, was significantly higher in cases of KNO
than in NH
Cl treatments, as an assumed consequence of the intensive denitrification.
It was found that the gaseous loss was not influenced by soil moisture. In contrast to the gaseous losses, the values
of plant N uptake and soil mineral N content showed significant differences in
the years studied, as a result of the quick transformation of mineral N to
organic N, the non-complete homogenization of the total soil amount, the
seasonal climatic differences in the greenhouse during the years studied, and
consequently the different microbiological activity. The plant N uptake was
found to depend significantly on the fertilizer N form. Results obtained by the
difference method and the
N-tracer technique were very similar. In
the case of KNO
treatment and higher soil moisture (WHC = 80%)
plant N uptake was more intensive, ranging between 48-57% (calculated by the
difference method), and 35-51% (calculated by the
method) in the first year (1993). It can be concluded that 60-100% of the
fertilizer N was used from the soil by plant uptake and gaseous losses, which
depends mainly on the treatments and the soil moisture during the first year.
These values changed between 7-17% in the 1
year after-effect and
between 1-5% in the 2
Authors:Marianna Magyar, P. Csathó, K. Debreczeni, and et al.
Five soil P-test
methods were compared on the soils of the network of unified Hungarian P
fertilization long-term field trials. The
effect of P application on the soil P-test values was significant on the
different P levels and sites. The average effect of the sites varied between
O method) and 3.7- fold (AL-method). The amounts of
extracted P increased in the order of H
O-P < Olsen-P < Pi-P
< AERM-P < AL-P < Corrected AL-P. For studying the relationships
between the P values extracted by the different methods, acidic, calcareous and
all soils groups were taken into account as a basis. A good correlation was
found between the Pi- and AERM-methods in each soil group. Within the acidic
soil group, pH has a much less expressed effect on AL-P values, presumably this
was the reason why the strongest correlation in this soil group was found
between the AL- and the Corr. AL-P methods
The next step in our research will be to calibrate these soil-P tests
with plant P uptake and yield responses.