Joint International Conference on Long-term Experiments ...

treatments and it was 12 kg/ha in the case of 200 kg/ha applied N-fertilizer. Take this
fact into account is important to evaluate accurately the results.
Ca conent (mg/kg)
800
700
600
500
400
300
200
100
0
2001 2004 2005 2001 2004 2005 2001 2004 2005
Karcag Iregszemcse Nagyhörcsök
Control 200 kg/ha
Figure 1: Ca content of winter wheat samples as an effect of N fertilization
The effect of N fertilization on the Mg content was inconsistent in all the three research
sites, depending on the crop year; it both decreased and increased the Mg concentration.
For example in 2002, applying 200 kg/ha N in Nagyhörcsök after winter wheat forecrop
significantly increased while in 2005 after corn forecrop decreased the Mg content of
the wheat grain samples.
In Karcag in 2001, after corn forecrop it significantly decreased while in 2005 after
winter wheat forecrop increased the Mg content of wheat grain samples. In the
Iregszemcse research site we found the opposite effect: N fertilization after corn
forecrop increased, while after winter wheat decreased the Ca content of wheat. In the
Nagyhörcsök research site in 2001 and 2002, the application of 200 kg/ha N doses
significantly increased the Mn content of winter wheat grain samples, while significant
effect was not fund in 2003-2005.
The effect of phosphorus fertilization on the mineral content of winter wheat
samples
The effect of phosphorus fertilization on the Mg and Mn content of winter wheat grain
samples were not significant either at 120 kg/ha dose, or in dry or humid crop years in
Karcag. The effect of phosphorus on the Ca content was statistically proved in one case:
in 2003, after corn forecrop the application of 120 kg/ha P2O5 active substance
decreased the Ca content of the wheat grain samples from 602,3±23,5 mg/kg to
544,0±24,0 mg/kg compared to the control plots. As regards samples from Iregszemcse
and Nagyhörcsök, the effect of phosphorus was significant in one crop year,
respectively. Applying 100 kg/ha P2O5 fertilizer significantly increased the Ca content
of wheat grain samples after winter wheat forecrop in Iregszemcse in 2002, and after
corn forecrop in Nagyhörcsökön in 2001.
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