Joint International Conference on Long-term Experiments ...

The amount of nitrogen uptake by the plants corresponds with the increasing nitrogen
supply. The amount of the nitrogen extracted from the soils was 97.2; 159.4 and
246.5 mg N per pot in the average of control treatments, at 40 mg kg -1 and at 80 mg kg -1
nitrogen doses, respectively (Table 5).
The amount of nitrogen extracted was dependent on the soil (P = 0,1 %). The
calcareous chernozem and the marshy meadow soil supplied the grass with
approximately the same amount of nitrogen, which can be explained by the fact that the
higher grass yield on the chernozem soil and the higher nitrogen content of plants on
marshy meadow soil offset each other. However, the ryegrass plants extracted only 110
mg nitrogen per pot from the brown forest soil.
Table 5: Nitrogen uptake of ryegrass (g pot -1 ) Sum of 1 st , 2 nd and 3 rd cuts
W.c. (%) Soil site N supply (mg kg -1 ) (A)
(C) (B) 0 40 80 Average
Pallag 61.6 113.3 206.2 127.0
50 Látókép 113.8 169.4 276.4 186.5
Dombos 112.8 189.7 248.9 183.8
Average 96.1 157.5 243.8 165.8
Pallag 60.0 95.7 125.0 93.6
75 Látókép 98.7 186.2 330.5 205.1
Dombos 136.4 202.2 292.1 210.2
Average 98.3 161.4 249.2 169.9
Pallag 60.8 104.5 165.6 110.3
Average Látókép 106.3 177.8 303.4 195.8
Dombos 124.6 196.0 270.5 197.0
Average 97.2 159.4 246.5 167.7
Table of variance
Factor FG MQ F SD 5%
A 2 134992.9 295.5 *** 12.40
B 2 59348.8 129.9 *** 12.40
A*B 4 4742.3 10.4 *** 21.48
C 1 265.3 0.6 10.13
A*C 2 14.1 0.0 17.54
B*C 2 6361.1 13.9 *** 17.54
A*B*C 4 3207.4 7.0 *** 30.38
Error 51 344.0
*** Significant at P=0.1 % level
In spite of the fact, that water dose had an effect both on yield quantity and the nitrogen
content of plants, the level of water supply did not influence the amount of nitrogen
uptake significantly. The reason for this was that while yield increased paralelly with
the water supply, the nitrogen content decreased. These two counter-effects balanced
each other in the nitrogen uptake of plants.
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