Table 3.
Phosphorus content (grams P per 100 g of fertilizer) of the fertilizers used in the soil–plant experiment
| Fertilizer | Total Pa | H2O-soluble Pb | CA-soluble Pc | NAC-soluble Pd |
|---|---|---|---|---|
| SB-70 | 1.7 | 0.5 | 0.9 | 0.4 |
| SB-350 | 4.4 | 0.3 | 0.4 | 0.4 |
| SB-500 | 7.4 | 0.1 | 3.5 | 1.3 |
| TSP | 22.3 | 18.0 | 19.6 | 20.5 |
| ARP | 14.0 | 0.3 | 1.7 | 0.4 |
a
Extracted with 6:1 nitric-hydrochloric acid mixture.
b
Soluble in H2O (1:200).
c
Soluble in 2% citric acid (1:100).
d
Soluble in neutral ammonium citrate.
ARP, Araxá rock phosphate; SB-70, SSF product dried at 70°C; SB-350, SSF product incinerated at 350°C; SB-500, SSF product incinerated at 500°C; TSP, triple superphosphate.