ONION NUTRITION

Phosphorus Deficiency in Onion

Identify Phosphorus (P) deficiency symptoms, understand causes and apply the correct treatment for Onion grown in Nashik, Pune, Solapur (Maharashtra), Rajasthan.

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🔍 Symptoms

Dark green or purple-red discolouration of older leaves (anthocyanin accumulation). Stunted root development. Delayed maturity, reduced tillering. Purple stems and leaf undersides in maize and tomato.

🧩 Cause

Cold soils reduce P uptake. Very acidic soils fix P as aluminium/iron phosphates. Alkaline soils fix as calcium phosphates. Compacted soils restrict root growth.

🌿 Crop Info

Region: Nashik, Pune, Solapur (Maharashtra), Rajasthan
Soil: Loamy, pH 6–7.5
Season: Kharif + Rabi

Correction Methods for Onion

ProductMethodRateBest For
DAP 18:46:00Soil20–25 kg/acre basalAll crops — sowing time
MAP 12:61:00 (WSF)Drip2–3 kg/acreDrip crops at transplanting + flowering
MKP 00:52:34 (WSF)Drip2 kg/acre at floweringFruit crops — zero N at flowering
SSP (Single Super Phosphate)Soil50 kg/acreBasal, also supplies sulphur

Step-by-Step Treatment Plan

  1. Confirm deficiency — Take leaf and soil samples. Send to lab or use visual diagnosis. Soil pH test critical (check at root zone depth).
  2. Immediate foliar correction — Apply DAP 18:46:00 at 20–25 kg/acre basal as emergency foliar spray. Spray in morning or evening. Repeat after 7–10 days.
  3. Drip/soil correction — Apply via drip fertigation or soil for lasting correction. Single foliar application is temporary fix only.
  4. Soil amendment — If soil pH is the cause: apply gypsum to reduce pH in alkaline soils, or lime if acidic. Target pH 6.5–7.5.
  5. Prevent recurrence — Include micronutrient schedule in regular fertigation program. Soil test every season.

Get Products for Onion

Buy DAP 18:46:00 Buy MAP 12:61:00 (WSF) Buy MKP 00:52:34 (WSF) Buy SSP (Single Super Phosphate) 🌿 Fertilizer for Onion 📈 Calculate Exact Dose

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