The primary nutrients supplied by fertilisers
are nitrogen, phosphorus and potassium. Their concentration
in a fertiliser is expressed as percentage of N, P2O5
and K2O.
In the case of nitrogenous fertilisers, nitrogen may
be in the ammoniacal, nitrate (or a combination thereof)
or amide form. Ammoniacal form of nitrogen is contained
in fertilisers like ammonium Sulphate, ammonium chloride,
etc. Nitrate nitrogen is contained in fertilisers like
ammonium nitrate, calcium ammonium nitrate, etc. The
amide nitrogen is contained in urea.
Phosphate present in phosphatic fertilisers may be in
the water soluble form or citrate soluble form. That
portion of phosphate which is soluble in water is called
water soluble phosphate and that which is not soluble
in water but in 2 per cent neutral ammonium citrate
solution is called citrate soluble phosphate. The sum
of water soluble and citrate soluble values is termed
as available phosphates. The portion of phosphate which
is neither soluble in water nor in 2 per cent neutral
ammonium citrate solutions is termed insoluble. The
sum of the available phosphate and insoluble phosphate
is termed as total phosphate.
In Table 1.2 (a & b), nutrient contents of
fertilisers mostly used in India are given. The figures
are in percentage of nutrient in the various fertilisers
and correspond to those in the Fertiliser (Control)
Order.
(Per cent by wt. min.)
| |
Material |
Total
Nitrogen
(N)
|
Ammoniacal
nitrogen
(N)
|
Nitrogen Nitrate
(N)
|
Nitrogen
in form of urea
(amide) (N)
|
Neutral
ammonium
citrate
soluble
phosphate (P2O5) |
Water
soluble
phosphate
(P2O5)
|
Water
soluble
potash
(K2O)
|
| |
(1) |
(2) |
(3) |
(4) |
(5) |
(6) |
(7) |
(8) |
| I |
Nitrogenous fertilisers |
| 1. |
Ammonium
Sulphate
|
20.6 |
20.6 |
|
|
|
|
|
| 2. |
Ammonium
chloride
|
25.0 |
25.0 |
|
|
|
|
|
| 3. |
Calcium
Ammonium Nitrate
|
25.0 |
12.5 |
12.5(max) |
|
|
|
|
| 4. |
Calcium
Ammonium Nitrate
|
26.0 |
13.0 |
13.0(max) |
|
|
|
|
| 5. |
Calcium Nitrate |
15.5 |
1.1(max) |
14.4 |
|
|
|
|
| 6. |
Urea |
46.0 |
|
|
46.0 |
|
|
|
| II |
Phosphatic fertilisers |
| 7. |
SSP 14%
SSP 16%
|
|
|
|
|
|
14.0
16.0
|
|
| 8. |
Rock Phosphate (powder/granular) |
|
|
|
|
18.0 |
|
|
| III |
Potassic fertilisets |
| 9. |
Potassium chloride (powder/granular) |
|
|
|
|
|
|
60.0 |
| 10. |
Potassium Sulphate |
|
|
|
|
|
|
50.0 |
| 11. |
Potassium Magnesium Sulphate |
|
|
|
|
|
|
22.0 |
| 12. |
Potassium Schoenite |
|
|
|
|
|
|
23.0 |
| IV |
Complex fertilisers |
| 13. |
Ammonium Phosphate |
|
|
|
|
|
|
|
| |
11-52-0 |
11.0 |
11.0 |
|
|
52.0 |
44.2 |
|
| |
1846-0 |
18.0 |
15.5 |
|
2.5(max) |
46.0 |
41.0 |
|
| 14. |
Ammonium Phosphate Sulphate
|
|
|
|
|
|
|
|
| |
16-20-0 |
16.0 |
16.0 |
|
|
20.0 |
19.5 |
|
| |
20-20-0 |
20.0 |
18.0 |
|
2.0(max) |
20.0 |
17.0 |
|
| |
18-9-0 |
18.0 |
18.0 |
|
|
9.0 |
8.5 |
|
| 15. |
Ammonium Phosphate Sulphate Nitrate
20-20-0
|
20.0
|
17.0 |
3.0(max) |
|
20.0 |
17.0 |
|
| 16. |
Nitrophosphate
20-20-0
23-23-0
|
20.0
23.0
|
10.0
11.5
|
10.0(max)
11.5(max)
|
|
23.0
23.0
|
12.0
18.5
|
|
| 17. |
Ammonium Nitrate Phosphate
23-23-0
|
23.0 |
13.0 |
10.0(max) |
|
23.0 |
20.5 |
|
| 18. |
Urea Ammonium Phosphate
28-28-0
24-24-0
20-20-0
|
28.0
24.0
20.0
|
9.0
7.5
6.4
|
|
16.5(max)
|
28.0
24.0
20.0
|
25.2
20.4
17.0
|
|
| 19. |
Potassium Nitrate (cystalline/prilled)
(13-0-45)
|
13.0 |
|
13.0 |
|
|
|
45.0 |
| 20. |
Mono Potassium Phosphate
(0-52-34)
|
|
|
|
|
|
52.0 |
34.0 |
| 21. |
NPK fertilisers
15-15-15
10-26-26
12-32-16
22-22-11
14-35-14
17-17-17
14-28-14
19-19-19
17-17-17
20-10-10
|
15.0.
10.0
12.0
22.0
17.0
14.0
19.0
17.0
20.0
|
7.5
7.0
9.0
7.0
14.0
5.0
8.0
5.6
8.5
3.9
|
7.5
8.5
|
3.0(max)
3.0(max)
15.0(max)
12.0(max)
6.0(max)
13.4(max)
17.1(max)
|
15.0
26.0
32.0
22.0
35.0
17.0
28.0
19.0
17.0
10.0
|
4.0
22.1
27.2
18.7
29.0
14.5
23.8
16.2
13.6
8.5
|
15.0
26.0
16.0
11.0
14.0
17.0
14.0
19.0
17.0
10.0
|
(Per cent by wt. min.)
