Joint International Conference on Long-term Experiments ...

increment, than with higher calcium carbonate dosaging. It has to be noted also, that
lime also had a positive effect on yield and it was more significant (P = 0.1 %) than that
of nitrogen.
Table 4: Dry matter production of perennial ryegrass (g pot -1 )
Újfehértó shifting sand, 1st+2nd cuts
Factors
N=80
Unlimed Limed Average
Ni=0 4.73 5.18 4.95
Ni=50 3.38 4.90 4.14
Ni=100 1.65 4.90 3.28
Average
N=160
3.25 4.99 4.12
Ni=0 5.85 6.63 6.24
Ni=50 4.85 7.05 5.95
Ni=100 0.88 5.80 3.34
Average
N average
3.86 6.49 5.17
Ni=0 5.29 5.90 5.59
Ni=50 4.11 5.97 5.04
Ni=100 1.26 5.35 3.31
Average
Table of variance
3.55 5.74 4.65
Factor MQ DF F SD5%
N 13.335 1 11.77 ** 0.62
Ni 22.811 2 20.14 *** 0.76
N*Ni 3.226 2 2.85 + 1.08
CaCO3 57.422 1 50.67 *** 0.62
N*CaCO3 2.385 1 2.11 0.88
Ni*CaCO3 12.393 2 10.94 *** 1.08
N*Ni*CaCO3 0.491 2 0.43 1.53
*** Significant at P=0.1 % level
** Significant at P=1.0 % level
+ Significant at P=10 % level
The yield-increasing effect of nitrogen had a significant interaction with nickel dosaging
at P = 10 % level. In treatments without nickel, nitrogen had a yield-increasing effect
both in limed and unlimed treatments. In the case of nickel treatment however, the
yield-reducing and yield-increasing effect of nickel and nitrogen, respectively, were
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