A pictorial description of functions and deficiency symptoms of Nitrogen, Phosphorus, and Potassium in plants.

1. Soil Fertility
Management
Mr. Aditya Kumar Verma

2. Topics for Discussion!
• Functions and Deficiency Symptoms of:
• Nitrogen
• Phosphorus
• Potassium

3. Crop Doctor!!

4. Nitrogen
(NO3
−
, NH4
+
)
• Functions of Nitrogen in Plants:
• Essential constituent of chlorophyll.
• Essential component of amino acids, proteins,
nucleic acids, porphyrins, enzymes,
hormones, etc.
• Improves the quality of leafy vegetables and
fodders.
• Imparts vigorous vegetative growth and dark
green colour to plants.
Concentration in
Mature Leaf Tissue:
1% - 5%

5. Nitrogen
(NO3
−
, NH4
+
)
Deficiency:
Older Leaves
• Yellowing of older leaves due to inhibition of
chloroplasts and chlorophyll synthesis.
• Dwarf or stunted growth.
• Reduction in flowering and crop yields.
• Lower protein content.
Deficiency Symptoms
• Succulence of the plants increases.
• Taller plants with weak stem and heavy top
leading to lodging.
• More susceptible to insect, pest and disease.
Excessive Supply

6. Nitrogen

7. Nitrogen
(NO3
−
, NH4
+
)
Deficiency:
Older Leaves

8. Nitrogen
(NO3
−
, NH4
+
)
Deficiency:
Older Leaves

9. Phosphorus
(H2PO4
−
, HPO4
2−
)
Functions of Phosphorus in Plants:
• Involved in energy storage and transfer.
• “Energy currency” of the plants (ADP and ATP).
• Important constituent of majority of enzymes.
• Involved in cell division.
• Important for root development and
stimulates root growth.
Concentration in
Mature Leaf Tissue:
0.1% - 0.4%

10. Phosphorus
(H2PO4
−
, HPO4
2−
)
Deficiency:
Older Leaves
• Stunted and slow growth of plants.
• Thin stem and darker green foliage.
• Purple coloration of foliage due to
anthocyanin pigment.
• Delay in flowering and ripening of fruits.
Deficiency Symptoms

11. Phosphorus

12. Phosphorus
(H2PO4
−
, HPO4
2−
)
Deficiency:
Older Leaves

13. Phosphorus
(H2PO4
−
, HPO4
2−
)
Deficiency:
Older Leaves

14. Potassium
(K+)
Functions of Potassium in Plants:
• Regulates the opening and closing of stomata.
• Activates more than 60 different enzymes.
• Impart drought/heat/frost resistance to plants
as it regulates transpiration and water
conditions in the plant cell.
• Impart pest and disease resistance to plants.
• Produces strong stiff straw in cereals and
thereby reduces lodging.
• Enhances crop quality, improves shelf-life of
fruits and vegetables.
Concentration in
Mature Leaf Tissue:
1% - 5%

15. Potassium
(K+)
Deficiency:
Older Leaves
• Tips and edges of older leaves turn to
yellow (chlorosis) and later die (necrosis).
• Susceptibility to lodging.
• Susceptibility to pests and diseases.
• Poor shelf-life of fruits and vegetables.
• Slow and stunted growth of plants.
Deficiency Symptoms

16. Potassium

17. Potassium
(K+)
Deficiency:
Older Leaves

18. Potassium
(K+)
Deficiency:
Older Leaves

19. Deficiency of
NPK