Masoor Dal (Lentil) Disease Diagnostic, Spray & Crop Calculator

Masoor (Lentil) is one of the oldest protein-rich pulse crops cultivated in India. Because it is grown primarily under rainfed conditions during the Rabi season, proper disease diagnosis, seed inoculation, and balanced sulphur nutrition are essential to achieve target yields of 15–20 quintals per hectare.

Major Masoor Diseases and Their Management:

• 1. Fusarium Wilt (उकठा रोग – Fusarium oxysporum f. sp. lentis): The primary cause of plant death in lentil fields. Seedlings or flowering plants suddenly droop, turn dull yellowish-brown, and dry up in patches. Inside the root and stem xylem, dark brown vascular discoloration appears. Preventive seed treatment with Saaf (Carbendazim 12% + Mancozeb 63% WP) @ 2.5 g/kg or Trichoderma viride @ 10 g/kg is essential. For standing crops, drench affected spots with Saaf @ 2.5 g/L.
• 2. Lentil Rust / Gerua (गेरुआ / रतुआ – Uromyces viciae-fabae): Common in humid, cool, or overcast weather. Small brownish-orange pustules erupt on the underside of leaves and stems. Heavily infected leaves wither and fall off, leaving bare twigs. Spray Tilt (Propiconazole 25% EC) @ 1 ml/L (16 ml / 16L pump) or Mancozeb 75% WP @ 2.5 g/L at first symptom onset.
• 3. Pod Borer (फली छेदक – Helicoverpa armigera): Green to brownish caterpillars bore into tender pods, eating developing seeds and leaving empty shells. Spray Proclaim (Emamectin Benzoate 5% SG) @ 8 g per 16 L pump or Coragen @ 6 ml per pump at 50% flowering and pod formation.
• 4. Black Aphids (माहू / चेपा – Aphis craccivora): Dense colonies of small dark aphids suck sap from flowers and new pods, causing flower drop and sooty mould. Spray Rogor (Dimethoate 30% EC) @ 25–30 ml per pump in late afternoon.

The Scientific FIR Seed Treatment Method:

Always treat Masoor seed in strict order F → I → R (Fungicide → Insecticide → Rhizobium Biofertilizer):

1. Fungicide: Treat with Saaf (Carbendazim + Mancozeb) @ 2.5 g/kg seed to kill seed-borne fungal spores.
2. Insecticide (Optional): If termites or aphids are troublesome, treat with Imidacloprid 600 FS @ 2 ml/kg seed.
3. Rhizobium + PSB: Dissolve 50 g jaggery in 250 ml warm water; coat seed with Rhizobium leguminosarum (5 g/kg) and PSB culture (5 g/kg). Dry in shade for 1 hour before sowing. This increases nitrogen fixation nodules by 40%.

Total Spray Water (L) = Water per Acre (L/acre) × Field Area (acres)
Medicine per Tank = Concentration (ml or g / L) × Tank Size (L)
Total Product Required = Concentration (ml or g / L) × Total Spray Water (L)
Small-Seeded Desi Seed Rate = 13 kg/acre (32 kg/ha)
Bold-Seeded Seed Rate = 17 kg/acre (42 kg/ha)
Basal Fertilizer = 35 kg DAP + 13 kg MOP + 10 kg Bentonite Sulphur (90%) per acre

• Never apply heavy nitrogen: As a legume, Masoor fixes 35–40 kg N/ha from the air. Applying more than 20 kg/ha starter nitrogen causes excessive vegetative growth and suppresses nodule formation.
• Sulphur is non-negotiable: Pulses need sulphur to synthesize methionine and cysteine amino acids. Applying 10 kg/acre Bentonite Sulphur (90%) increases grain yield by 15–20% and prevents yellowing.
• Irrigation timing: Masoor needs only 1–2 light irrigations. Critical stages are 40–45 days after sowing (pre-flowering) and early pod formation. Never flood the field, as standing water triggers catastrophic root rot and wilt.
• Spray timing for honeybees: Lentil is a self-pollinating crop that benefits from bee activity. Always spray insecticides like Rogor or Proclaim after 4:00 PM when bees have returned to their hives.