Joint International Conference on Long-term Experiments ...

samples were measured by the ICP-AES technique after their microwave digestion
using concentrated HNO3+H2O2. The soil and plant analyses were done in the
laboratory of the Research Institute for Soil Science and Agricultural Chemistry
(RISSAC), Budapest, Hungary.
The soil characteristics: By soil test (end of March 2003) acid reaction (pH in 1nKCl =
4.98), low organic matter contents (1.86%) and moderate levels of mobile phosphorus
and potassium (5.20 mg P2O5 and 8.13 mg K2O 100 g of soil -1 according the ALmethod)
were found.
RESULTS AND DISCUSSION
In general, in spite of relative low status of plant available P were found by the
preliminary soil test, response of maize to ameliorative fertilization was low because
yield were increased up to 10% only (Table 1). We presume that Al-method is not
suitable solution for prediction of plant available P status in this soil. Ameliorative
fertilization resulted by significant influences on increased plant available phosphorus,
potassium and iron status only, while differences of the other tested elements was in
level of statistical error. Applied fertilization influenced on moderate increases of soil
reaction (pH value), while humus contents were similar for all fertilization treatments.
Also, values of plant available P and K which were determined by two extraction
methods are similar (Table 2).
Table 1. Realized plant density and grain yield of maize as affected by ameliorative
fertilization - the experiment Korenicani (Kovacevic et al., 2006)
a)
b)
c)
d)
Fertilization* Realized plant density (RPD in %TPD=theoretical plant
(17. 04. 2003.) density) and grain yield of maize**
kg ha -1 Maize hybrid OsSK 552 Hybrid OsSK 499
2003 2004 2005
RPD Yield RPD Yield RPD Yield
NPK CAN % t ha -1 % t ha -1 % t ha -1
0 974 87.3 12.38 73.7 10.12 98.9 11.78
1250 649 85.9 13.33 72.4 10.87 94.0 11.92
2500 325 89.4 13.52 70.1 11.17 94.6 11.88
3750 0 84.6 13.41 72.7 10.82 96.1 11.89
Mean 86.8 13.16 72.2 10.75 95.9 11.87
TPD (plants ha -1 ) 51948 54946 57243
LSD 5% 0.54 0.17 n.s.
* for 2004 and 2005 standard fertilization of the a-d treatments; **yield calculations on
14% moisture basis and TPD 90% (2003), 70% (2004) and 95% (2005), respectively.
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