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Element Ammonium-nitrate Superphosphate Potassium-chloride
Ca 6,0 % 17,4 % 3470
Mg 23,8 570 302
Mn 0,299 152 19
Source: Győri (1998).
The winter wheat grain samples in our analysis are from three research sites: Karcag,
Nagyhörcsök and Iregszemcse. The soil type is meadow chernozem in Karcag and
calcareous chernozem at the other two research sites. Table 1 shows the characteristics
of the cultivated layer of the soil at the different research sites. The dates of control
plots are calculated from the averages of results of the 10 th , the 16 th and the 20 th years.
Table 1: Nutrient supply in different research sites
Parameters Karcag Nagyhörcsök Iregszemcse
Humus content (%) 2,7 (medium) 2,7 (good) 2,4 (medium)
AL-P2O5 (mg/kg) 34 (very weak) 81 (weak) 103 (medium)
AL-K2O (mg/kg) 270 (good) 147 (medium) 150 (medium)
pHKCl 4,7 7,2 7,4
KA 47 38 37
Source: Debreczeni and Debreczeniné (1994)
The analyses were carried out by the accredited laboratory of the Institute of Food
Science, Quality Assurance and Microbiology of the Faculty of Agriculture of the
Centre for Agricultural Sciences of the University of Debrecen. The mineral element
contents of the samples were determined with OPTIMA 3300 DV ICP-OES (Perkin-
Elmer Ltd. Wellesley, USA) using No. BCR CRM 189 certified reference material
(Kovács et al., 1996, 1998). The concentrations of calcium, magnesium and manganese
of wheat samples are shown in this article.
The data were evaluated by using one-way ANOVA, and there were carried out average
and standard deviation calculations run on SPSS 11.5 for Windows and Excel 6.0 for
Windows.
RESULTS
The effect of N fertilization on the mineral content of winter wheat samples
The applied N fertilization significantly increased the Ca content of wheat samples in
every studied crop year in Karcag (Figure 1). At the Iregszemcse research site, the
effect of N fertilization on the Ca content was proved by variance analysis only in some
cases, however, this time the 150 and 200 kg/ha N doses– similarly to the results in
Karcag– increased the Ca content in each case. In the Nagyhörcsök research site,
similarly to the effects in Karcag, the effect of the N fertilization was clear: the various
doses of N fertilizers had a positive effect on the Ca content of wheat samples.
According to Győri’s (1998) measurements the Ammonium-nitrate has 6% Ca as
additional element in the fertilizer. The amount of Ca was 0 kg/ha in the control
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