Sunflower (Helianthus annuus L.)

1. Origin and History

• Origin: North America (Mexico → Southern USA).
• Cultivated by Native Americans >2000 years ago.
• Introduced to Europe in 16th century (via Spanish explorers).
• Came to India during the 1960s; popularized during the Yellow Revolution.

2. General Information

• Belongs to family Asteraceae (Compositae).
• Known as “King of Oilseeds” due to high-quality edible oil.
• Oil content: 40–45% (rich in polyunsaturated fatty acids).
• Protein content: 18–20% in seed.
• Short duration crop (70–110 days) → fits into multiple cropping systems.
• Grown in both Kharif & Rabi seasons.

3. Area, Production & Distribution (India, 2023)

• Area: ~0.25 million ha.
• Production: ~0.2 million tonnes.
• States: Karnataka (largest) > Andhra Pradesh > Maharashtra > Tamil Nadu.
• India’s rank: Among top 10 producers globally, but production declining (competition from soybean & palm oil).

4. Climatic Requirements

• Temperature: Optimum 20–25°C (germination at 8–10°C).
• Rainfall: 500–700 mm (well-distributed).
• Photoperiod: Day-neutral (grows in both long & short days).
• Sensitive to: Frost & continuous cloudiness (reduces seed set).
• Unique feature: Heliotropism (sun tracking) in vegetative phase.

5. Soil

• Well-drained sandy loam to clay loam.
• Optimum pH: 6.5–8.0.
• Tolerant to light salinity but sensitive to waterlogging.

6. Varieties / Hybrids

• Public sector hybrids: BSH-1, APSH-11, CO-4.
• Private hybrids: KBSH-1, KBSH-44, PAC-36, MSFH-17.
• Duration: 80–110 days depending on variety.

7. Agronomy (Cultural Practices)

• Season: Kharif (June–July), Rabi (Oct–Nov), Summer (Jan–Feb in irrigated tracts).
• Seed rate: 8–10 kg/ha (hybrids).
• Spacing: 60 × 30 cm.
• Sowing depth: 3–5 cm.
• Fertilizer requirement:
  • N: 60–80 kg/ha
  • P₂O₅: 60 kg/ha
  • K₂O: 40 kg/ha
  • S: 20–30 kg/ha (improves oil quality).
• Biofertilizer: Azospirillum + PSB recommended.
• Irrigation: Critical stages →
  • Flower initiation (30 DAS)
  • Anthesis (45–55 DAS)
  • Seed filling (65–75 DAS).
  • Requires 4–6 irrigations in total (depending on season).

8. Weed Management

• Critical period: First 40 DAS.
• Hand weeding at 20 & 40 DAS.
• Herbicides:
  • Pendimethalin @ 1.0 kg a.i./ha (PE).
  • Imazethapyr @ 75 g a.i./ha (20 DAS, POE).

9. Pests & Diseases

• Insect pests:
  • Capitulum borer (Helicoverpa armigera).
  • Bihar hairy caterpillar.
  • Sunflower head beetle.
• Diseases:
  • Alternaria blight (Alternaria helianthi).
  • Rust.
  • Downy mildew.
  • Sclerotinia stem rot.
• Management:
  • Seed treatment with Carbendazim.
  • Resistant hybrids.
  • Need-based sprays (Mancozeb, Triazoles, Pyrethroids).

10. Quality Components

• Oil content: 40–45%.
• Fatty acids:
  • Linoleic acid: 48–74% (PUFA).
  • Oleic acid: 14–39%.
  • Palmitic + Stearic acids: ~10%.
• Protein: 18–20%.
• Special note: Oil is light-colored, bland taste, high stability → excellent edible oil.

11. Industrial & Food Uses

• Edible oil (refined, salad oil, cooking).
• Used in margarine, bakery, confectionery.
• Non-edible: Soaps, paints, biodiesel.
• Oilcake: Protein-rich livestock feed.
• Sunflower heads & stalks used as fodder and fuel.

12. Economics

• Moderate input crop.
• B:C ratio ~1.6–2.0 depending on season & irrigation.
• Profitable as intercrop with pigeonpea, maize, cotton.

13. Post-harvest Technology

• Harvest when back of head turns lemon-yellow & seeds are black with white stripes.
• Avoid over-ripening (shattering loss).
• Threshing: Beating or sunflower thresher.
• Dry seeds to 8–9% moisture for safe storage.

14. Important MCQ Facts (Quick Recap)

• Botanical name: Helianthus annuus L.
• Family: Asteraceae.
• Origin: North America (Mexico/USA).
• Oil content: 40–45%.
• Protein content: 18–20%.
• Seed rate: 8–10 kg/ha.
• Spacing: 60 × 30 cm.
• Critical irrigations: Flower initiation, anthesis, seed filling.
• Major pest: Capitulum borer (Helicoverpa armigera).
• Major disease: Alternaria blight.
• Special feature: Heliotropism.