fertilizers

1. Fertilizer – Definition-
Components and its
classification

2. Soil fertility and soil productivity
“Soil fertility is the ability of the soil to
supply essential plant nutrients during growth
period of the plants, without toxic
concentration of any nutrients”.
“the capacity of the soil to supply nutrient in
available form to crop”.

3. Soil fertility and soil productivity
“Soil productivity is the ability of the soil to
produce a particular crop or sequence of crops
under specified management system”
All productive soils are fertile but all fertile
soils need not be productive”

4. Fertilizer
• Fertilizer is any material of natural or synthetic
origin added to the soil to supply one or more
plant nutrients
• Usually fertilizers are inorganic in nature and
most of them are products of different
industries. (exceptions are urea and CaCN2 –
organic fertilizers)

5. Classification of Fertilizers
Fertilizers
Straight
Complex
Mixed

6. Classification of Fertilizers
Straight
fertilizers
• Supply only
one primary
plant nutrient
(N, P & K)
• Urea-N
• SSP
• MOP
Complex
fertilizers
• Contains two
or three
primary plant
nutrients
• Diammonium
phosphate (N,P)
• Mono
ammonium
phosphate
• Ammonium
phosphate
sulphate
Mixed
fertilizers
• Physical
mixtures of
straight
fertilizers
• They contain
two or three
primary plant
nutrients.
• 19:19:19 of
NPK

7. Fertilizer
Complete fertilizer
• Which contains all three major nutrients
(N, P & K)
Incomplete fertilizer
• Which lacks any one of the three major nutrients
Acid ,Base and Neutral fertilizers
Fertilizer Grade
• Refer to minimum guarantee of the available plant
nutrients expressed as a percentage by weight in a
fertilizer in terms of total N, P2O5 ,K2O (Complex /
Mixed) 12:32:16 grade of NPK complex fertilizer

8. Classificationn of Fertilizers

9. Nitrogen fertilizer

10. Fertilizer

11. Phosphatic fertilizers
• Phosphorus present in the phosphatic fertilizer
is usually expressed as phosphorus pentoxide
(P2O5)
• Phosphorus moves very slowly from the point
of placement
Water soluble
Mono-
calcium
phosphate
Citric acid
soluble
Di-calcium
phosphate
Citric acid (or)
water insoluble
Tri-calcium
phosphate

12. Classification of phosphatic fertilizers
Water
soluble
SingleSuper
Phosphate-16-18%-
Ca(H2PO4)2.H2O
Doublesuper
phosphate-32%
2Ca(H2PO4)2.H2O
T
ripleSuper
Phosphate-46-
48%
3Ca(H2PO4)2.H2O
Citricacid
soluble
Dicalcium
phosphate-
40% CaHPO4
Basicslag- 13-18%
(CaO)3P2O5SiO2
Citric
acid
insoluble
Rock
phosphate-
20-40%
Bonemeal-
20-25%
*Rhenania phosphate- 26-28%

13. Potassic fertilizers
S.No Name of fertilizers Composition K2O%
1 Fertilizers containing K in the
chloride form Eg. Muriate of
potash
KCl 60
2 Fertilizers containing K in non
chloride
form
Eg. Potassium
sulphate/Sulphate
of potash
K2SO4 48-52
3 Potassium magnesium sulphate K2SO4, 2MgSO4 22
4 Potassium schoenite K2SO4,
2MgSO4.6H2O
22-24