Joint International Conference on Long-term Experiments ...

RESULTS AND DISCUSSIONS
The dry matter production of the perennial ryegrass reduced with time (main average:
1 st cut: 4.02; 2 nd cut 2.04; 3 rd cut: 1.78 g per pot). The reasons for the reduction of dry
matter production are the nutrient-deficiency originating from low soil mass and the
ageing of grasses. The nutrient supply of soils heavily influenced the dry matter
production of plants at all cuts. In the average of treatments, the calcareous chernozem
soil was the most productive (significant at P = 0.1 % level), while the productivity of
the brown forest and the marshy meadow soil was similar (Table 3).
The dry matter production increase due to the nitrogen treatment varied for the different
soils. This is supported by the fact, that the interaction of factors A*B (N dose*soil
type) is highly significant (mostly P = 0,1 %). The application of 80 mg kg -1 nitrogen
doubled the yield on the brown forest and the calcareous chernozem soil, while on the
marshy meadow soil with high organic matter content the increase was also significant,
but smaller (30 %).
Table 3: Dry matter production 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 4.38 7.43 10.53 7.44
50 Látókép 6.92 8.75 11.57 9.08
Dombos 5.10 6.60 7.27 6.32
Average 5.47 7.59 9.79 7.62
Pallag 4.40 5.80 6.73 5.64
75 Látókép 7.33 10.82 14.43 10.86
Dombos 6.48 7.70 8.85 7.68
Average 6.07 8.11 10.00 8.06
Pallag 4.39 6.61 8.63 6.54
Average Látókép 7.13 9.79 13.00 9.97
Dombos 5.79 7.15 8.06 7.00
Average 5.77 7.85 9.90 7.84
Table of variance
Factor FG MQ F SD 5%
A 2 102.30 117.6 *** 0.54
B 2 83.18 95.6 *** 0.54
A*B 4 6.68 7.7 *** 0.94
C 1 3.51 4.0 * 0.44
A*C 2 0.26 0.3 0.77
B*C 2 22.88 26.3 *** 0.77
A*B*C 4 5.18 6.0 *** 1.33
Error 51 0.87
*** Significant at P=0.1 % level
* Significant at P=5.0 % level
The higher level of water supply increased the perennial ryegrass dry matter production
at every cut. The significance of the B*C (soil*water capacity) interaction (P=0,1 %)
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