Functions and deficiency symptoms of nutrients

Macronutrients

1. Nitrogen (N)

• Functions:
  • Essential for the synthesis of amino acids, proteins, and chlorophyll.
  • Plays a key role in photosynthesis, respiration, and overall plant growth.
  • Vital for cell division, cell enlargement, and the formation of vegetative tissue (roots, stems, and leaves).

• Deficiency Symptoms:
  • Chlorosis (yellowing) of the older leaves (because nitrogen is mobile and moves to younger tissues).
  • Stunted growth and reduced overall plant size.
  • Reduced leaf size and poor root development.
  • Pale green or yellowish leaves with veins remaining green.

2. Phosphorus (P)

• Functions:
  • Integral part of ATP, DNA, and RNA; essential for energy transfer and storage.
  • Important for root development, flowering, and seed production.
  • Aids in the formation of phospholipids in cell membranes.
• Deficiency Symptoms:
  • Purpling of older leaves (due to the accumulation of anthocyanin pigments).
  • Stunted growth, especially in roots.
  • Poor flowering, fruiting, and seed formation.
  • Necrosis (death) at the tips of older leaves.

3. Potassium (K)

• Functions:
  • Regulates stomatal opening and closure, thus controlling water loss and gas exchange.
  • Enhances disease resistance and improves the plant’s drought tolerance.
  • Important for the activation of enzymes involved in photosynthesis and other metabolic processes.
• Deficiency Symptoms:
  • Chlorosis on the edges of older leaves, progressing to necrosis (drying or browning).
  • Weak stems that are prone to lodging (falling over).
  • Reduced root growth and poor fruit/seed formation.
  • Spots or streaks on older leaves, starting at the leaf tips.

4. Calcium (Ca)

• Functions:
  • Key structural component of cell walls and plasma membranes, providing stability.
  • Activates certain enzymes involved in various metabolic processes.
  • Regulates cell division and elongation, and facilitates nutrient uptake.
• Deficiency Symptoms:
  • Necrosis (death) of young leaves and shoot tips (due to poor cell wall development).
  • Reduced root elongation, causing poor growth in root systems.
  • Deformed leaves (e.g., curled, distorted).
  • Blossom-end rot in fruits like tomatoes and peppers.

5. Magnesium (Mg)

• Functions:
  • Central atom in the chlorophyll molecule, crucial for photosynthesis.
  • Activates enzymes involved in carbohydrate and protein synthesis.
  • Plays a role in ATP production and energy transfer.
• Deficiency Symptoms:
  • Interveinal chlorosis (yellowing between leaf veins) in older leaves.
  • Leaf curling and necrosis at the leaf tips.
  • Stunted growth and reduced plant vigor.

6. Sulfur (S)

• Functions:
  • Component of amino acids like methionine and cysteine, which are vital for protein synthesis.
  • Crucial for the production of vitamins (e.g., vitamin B1) and coenzymes.
  • Plays a role in photosynthesis, especially in the formation of chloroplasts.
• Deficiency Symptoms:
  • Yellowing of younger leaves (similar to nitrogen deficiency).
  • Stunted growth, with reduced root and leaf size.
  • Poor flowering and fruiting.
  • Pale green leaves, particularly the new leaves.

Micronutrients

7. Iron (Fe)

• Functions:
  • Vital for the synthesis of chlorophyll.
  • Plays a central role in electron transport during photosynthesis and respiration.
  • Involved in enzyme activation and nitrogen fixation in legumes.
• Deficiency Symptoms:
  • Interveinal chlorosis (yellowing between veins) of young leaves.
  • Stunted growth.
  • Iron deficiency is more likely in alkaline or high pH soils.

8. Manganese (Mn)

• Functions:
  • Involved in the photosynthesis process, particularly in the water-splitting reaction.
  • Activates enzymes involved in nitrogen metabolism, carbohydrate synthesis, and lipid formation.
  • Assists in the formation of chlorophyll and the reduction of nitrate to ammonia.
• Deficiency Symptoms:
  • Interveinal chlorosis in younger leaves, followed by necrosis.
  • Brown spots on leaves, especially on older leaves.
  • Poor growth and weak stems.

9. Zinc (Zn)

• Functions:
  • Key role in protein synthesis and enzyme function.
  • Involved in growth regulation and flowering.
  • Helps in the synthesis of auxins (growth hormones) which regulate plant growth.
• Deficiency Symptoms:
  • Reduced internode length, resulting in dwarfing.
  • Chlorosis of younger leaves.
  • Deformed leaves and leaf rolling.
  • Poor flowering and fruit development.

10. Copper (Cu)

• Functions:
  • Essential for the activation of enzymes involved in photosynthesis and respiration.
  • Involved in oxidation-reduction reactions in plants.
  • Plays a role in lignin synthesis for cell wall formation.
• Deficiency Symptoms:
  • Chlorosis in young leaves.
  • Stunted growth and poor root development.
  • Dieback of shoots and branches.
  • Wilted leaves and reduced flowering.

11. Boron (B)

• Functions:
  • Essential for the formation of cell walls, particularly in the middle lamella.
  • Involved in sugar transport and seed development.
  • Plays a role in pollination and fruit set.
• Deficiency Symptoms:
  • Death of growing points (apical meristems), resulting in growth abnormalities.
  • Stunted growth and poor root development.
  • Brittle leaves and deformed flowers.

12. Molybdenum (Mo)

• Functions:
  • Required for the activity of the enzyme nitrate reductase, involved in reducing nitrates to ammonium for protein synthesis.
  • Involved in nitrogen fixation in legumes.
• Deficiency Symptoms:
  • Chlorosis in older leaves, with necrotic spots.
  • Stunted growth, particularly in legumes.
  • Poor nitrogen assimilation leading to reduced crop yields.

13. Chlorine (Cl)

• Functions:
  • Involved in osmotic regulation and ionic balance in plant cells.
  • Plays a role in the photosynthesis process, specifically in the water-splitting reaction.
• Deficiency Symptoms:
  • Chlorosis (yellowing) of older leaves.
  • Wilting and reduced growth rate.
  • Spots on the leaves and leaf drop.