Joint International Conference on Long-term Experiments ...

The much better performance of the mineral nutrient form can be the result of the better
utilization, especially that of N.
The higher TOC contents as a result of the FYM treatments suggest, that higher N
quantities were incorporated into the humic substances from the organic fertilizer,
which resulted in a lesser N supply and lower crop yields. The highest yields could be
achieved with the combined treatments with high NPK content
NO3-N (mg/kg)
0 20
0
30
60
90
120
150
180
210
240
270
300
Control
NO3-N (mg/kg)
1 FYM
NO3-N (mg/kg)
1 eqv FYM
NO3 – N mgkg -1
NO3-N (mg/kg)
2 FYM
NO3-N (mg/kg)
2 eqv FYM
NO3-N (mg/kg)
Figure 6 :Nitrate-N content of soil (0-300cm)mgkg -1
After harvest all the plots contained relatively high amounts of nitrate in the 0-300 cm
soil layer (Figure 6). Nitrate content of the non-treated plot was considerably high as
well. Despite the low yield response to FYM-treatments, less nitrate was found in the
soil, than with mineral fertilization. The lower nitrate reserves in the soil with FYM
treatments, in parallel with the lower crop yields, also confirms our suggestion that
higher N quantities were incorporated into the humic substances from the organic than
from the mineral fertilizers.
The amount of ammonium was higher, but it did not show any correlation with
fertilization.
73
3 FYM
NO3-N (mg/kg)
3 eqv FYM
NO3-N (mg/kg)
4 eqv FYM