Almost every yield-loss complaint in Indian fields can be traced to one or more nutrient deficiencies. The plant cannot speak, but it shows clear symptoms on its leaves, stem, and fruits. Learning to read those symptoms and knowing the right fix is one of the most powerful skills a farmer can build.

Why Nutrient Deficiencies Happen

• Unbalanced fertilizer use (too much urea, too little PK and micronutrients).
• Continuous cropping without organic manure or rotation.
• Soil pH too low or too high.
• Waterlogging or drought stress.
• No soil testing — farmers apply blindly.

1. Nitrogen (N) Deficiency

Most common deficiency in Indian fields, even though urea is the most widely used fertilizer.

Symptoms

• Pale yellow colour starting from older lower leaves.
• Stunted growth and thin tillers.
• Reduced grain or fruit set.

Correction

• Apply urea or DAP based on soil test.
• Split nitrogen into 2 to 3 doses for cereals.
• Use neem-coated urea to reduce losses.
• Add organic manure for long-term improvement.

2. Phosphorus (P) Deficiency

Critical for root development, flowering, and early growth.

Symptoms

• Dark green or purplish colour on older leaves and stems.
• Slow growth and poor root development.
• Delayed flowering and maturity.

Correction

• Apply DAP or SSP at basal, before sowing — phosphorus moves slowly in soil.
• Use phosphate solubilizing bacteria (PSB) at 200 g per acre seed treatment.
• Correct soil pH if very acidic (apply lime) to release fixed phosphorus.

3. Potassium (K) Deficiency

Potassium controls water use, disease tolerance, fruit quality, and grain filling.

Symptoms

• Yellowing or scorched edges of older leaves.
• Weak stems prone to lodging.
• Poor fruit colour and small fruit size.
• Increased susceptibility to pests and diseases.

Correction

• Apply MOP or SOP based on soil test.
• Foliar spray 0:0:50 (SOP) at 5 g per litre at flowering and fruit development.
• Use 13:0:45 at grain filling stage in cereals.

4. Zinc (Zn) Deficiency

Widespread in 40 to 50 percent of Indian soils.

Symptoms

• Paddy: bronze-coloured patches (Khaira disease).
• Wheat and maize: white interveinal bands on young leaves.
• Citrus, pomegranate: small, narrow leaves, rosetting.
• Reduced tillering and stunted growth.

Correction

• Soil: Zinc sulphate 10 to 25 kg per acre once in 2 to 3 years.
• Foliar: 0.5 percent zinc sulphate spray with 0.25 percent lime.
• Seed treatment with zinc sulphate slurry at 3 to 4 g per kg.

5. Boron (B) Deficiency

Often called the 'flowering and fruit setting' nutrient.

Symptoms

• Flower drop and poor fruit setting.
• Hollow stem in cauliflower and brassicas.
• Cracked, deformed fruits in tomato, pomegranate, mango.
• Twisted, brittle young leaves.

Correction

• Soil: Borax 4 to 8 kg per acre in deficient soils.
• Foliar: 0.1 to 0.2 percent borax or Solubor at flowering and fruit set.
• Do not over-apply — boron has a narrow margin between deficiency and toxicity.

Quick Symptom-to-Cause Table

Symptom	Likely Deficiency
Old leaves uniformly pale yellow	Nitrogen
Purplish leaves and stems	Phosphorus
Brown scorched leaf edges	Potassium
White or bronze patches on young leaves	Zinc
Flower drop and cracked fruits	Boron

Best Practices for Long-Term Soil Health

• Get a soil test every 2 to 3 years.
• Use FYM, compost, vermicompost regularly.
• Follow crop rotation; include a legume every 2 to 3 years.
• Apply micronutrients along with NPK as per soil test.
• Avoid burning crop residue — it destroys organic carbon.

Conclusion

Recognising the top 5 nutrient deficiencies — nitrogen, phosphorus, potassium, zinc, and boron — helps every farmer protect yield and reduce wasted fertilizer. Confirm with a soil test, follow label dose, and consult your local KVK or agriculture officer for region-specific recommendations.