Sunflower

Area & Production Scenario

• Sunflower is grown in more than 70 countries worldwide.
• Major producers: Russia, Ukraine, Argentina, EU countries, India.
• In India, productivity is lower due to cultivation under rainfed conditions.
• Karnataka is the leading sunflower producing state.

Taxonomy

• Kingdom → Plantae
• Order → Asterales
• Family → Asteraceae
• Genus → Helianthus
• Species → annuus

Growth Stages of Sunflower

• Germination (4–7 days)
• Seedling stage (10–15 DAS)
• Vegetative growth (20–40 DAS)
• Bud initiation (45–55 DAS)
• Flowering (60–70 DAS)
• Seed filling (70–90 DAS)
• Physiological maturity (90–110 DAS)
• Duration varies with variety and season.

Phenology & Flowering Biology

• Sunflower exhibits protandry (anthers mature before stigma).
• Disc florets open in rings from outer to inner.
• Each head flowers for 5–10 days.
• Bee activity improves seed setting.

Role of Pollinators

• Honeybees increase seed set by 20–30%.
• Important pollinators: Apis mellifera, Apis cerana
• Recommended to place bee colonies near field.

Root System Characteristics

• Roots can penetrate up to 2–3 meters depth.
• Efficient in extracting nutrients from deeper layers.
• Helps in drought tolerance.

Nutrient Uptake Pattern

Sunflower removes high amounts of nutrients:

• Nitrogen → Promotes vegetative growth
• Phosphorus → Root development and flowering
• Potassium → Seed filling and oil content
• Sulphur → Improves oil quality
• Boron → Essential for seed set
• Boron deficiency causes empty seeds.

• Micronutrient Management: Boron application @1–2 kg/ha improves seed filling. Zinc improves growth in deficient soils.
• Water Requirement: Total water requirement → 500–600 mm. Water stress during flowering reduces yield drastically. Excess moisture leads to root rot.
• Canopy Development: Large leaf area index helps efficient photosynthesis. Early canopy closure suppresses weeds.
• Oil Quality Parameters: Rich in linoleic acid (PUFA). Low cholesterol oil. High oxidative stability.
• Hybrid Seed Production: Sunflower hybrids developed using cytoplasmic male sterility (CMS). Three line system: A line (male sterile), B line (maintainer), R line (restorer). Important concept for breeding exams.
• Harvest Index: Approximately 35–40%
• Residual Effect: Improves soil structure, Good preceding crop for cereals
• Post Harvest Handling: Dry seeds to 9% moisture, Store in cool dry conditions, Prevent rancidity
• Cropping System Suitability: Ideal catch crop due to short duration. Suitable for intercropping with legumes
• Stress Tolerance: Moderate drought tolerance, Sensitive to waterlogging, Tolerates mild salinity
• Seed Quality Parameters: Test weight → 40–60 g, Germination standard → >70%

Advanced Exam Facts

• Sunflower shows protandry
• CMS used in hybrid production
• Boron essential for seed set
• Head is composite inflorescence
• Achene is a cypsela type fruit
• High nutrient exhausting crop

Conceptual Insights

• Yield mainly depends on number of filled seeds per head.
• Oil accumulation occurs during seed filling stage.
• Pollination efficiency directly affects productivity.

Most Repeated Exam Points

• Fruit → Achene
• Inflorescence → Capitulum
• First hybrid → KBSH-1
• Origin → North America
• Pollination → Insect pollinated
• C3 plant
• Botanical name → Helianthus annuus
• Family → Asteraceae (Compositae)
• Origin → North America
• Chromosome number → 2n = 34
• Crop type → Oilseed crop
• Pollination → Cross pollinated (entomophilous)
• Major pollinators → Honeybees
• Photosynthetic pathway → C3 plant
• Photoperiod → Photo-insensitive
• Inflorescence → Capitulum (head)
• Fruit type → Achene (cypsela)
• Ray florets → Sterile
• Disc florets → Fertile
• Oil content → 38–48%
• Oil quality → Rich in linoleic acid
• Crop duration → 90–110 days
• Root system → Deep tap root
• Drought tolerance → Moderate
• Sensitive to → Waterlogging
• Ideal temperature → 20–25°C
• Seed rate → 5–8 kg/ha
• Spacing → 60 × 30 cm
• Critical stages → Bud initiation, flowering, seed filling
• First sunflower hybrid in India → KBSH-1
• Hybrid seed production uses → CMS system
• Harvest index → 35–40%
• Major pest → Head borer
• Major disease → Alternaria blight
• Major sunflower producing state → Karnataka
• Best soil → Well-drained loam
• Oilcake protein → 25–30%
• Head size determines → Yield potential
• Protandry present in → Sunflower flowers
• Total water requirement → 500–600 mm
• Sunflower is called → Golden crop

Safflower (Carthamus tinctorius)

Introduction: Safflower is a rabi oilseed crop grown mainly in dryland areas. It is one of the oldest cultivated oilseed crops and is valued for its high-quality edible oil and drought tolerance.

Importance

• Seeds contain 28–35% oil rich in linoleic acid (heart-healthy).
• Oil used for edible purposes, paints, varnishes, and cosmetics.
• Petals used as natural dye and medicinal purposes.
• Oilcake used as cattle feed.
• Suitable crop for rainfed and residual moisture conditions.
• Deep roots improve soil structure.

Botanical & General Facts

• Botanical name → Carthamus tinctorius
• Family → Asteraceae (Compositae)
• Origin → Middle East / Ethiopia region
• Chromosome number → 2n = 24
• Crop type → Oilseed
• Pollination → Mostly self pollinated

Morphology

• Root: Deep tap root system (up to 2 m depth)
• Stem: Erect, branched
• Leaves: Spiny or non-spiny types
• Flower: Orange, yellow or red
• Inflorescence: Capitulum
• Fruit: Achene

Climate Requirement

Highly drought tolerant crop.

Soil Requirement: Best soil → Deep black soils and well-drained loams. pH → 6.0–8.5. Tolerates saline and alkaline soils better than other oilseeds

Season: Mainly grown in rabi season (Oct–Nov sowing).

Varieties: A-1, Bhima, NARI-6, JSF-1, PBNS-12

Agronomic Practices

• Seed rate: 10–15 kg/ha
• Spacing: 45 × 20 cm
• Depth: 5–6 cm

Nutrient Management: Nitrogen → 40–60 kg/ha, Phosphorus → 20–40 kg/ha. Excess nitrogen causes lodging.

Weed Management: Critical period → 20–40 DAS. Control:: One hand weeding at 25 DAS

Harvesting: Harvest when leaves dry and heads turn brown. Delay causes seed shattering.

Yield: Average yield → 8–12 q/ha. Oil content → 28–35%

High Yield Exam Facts

• Fruit type → Achene
• Inflorescence → Capitulum
• Oil content → ~30%
• Deep rooted crop
• Drought tolerant oilseed
• Rabi season crop
• Family → Asteraceae
• Botanical name → Carthamus tinctorius
• Family → Asteraceae (Compositae)
• Origin → Middle East / Ethiopia region
• Chromosome number → 2n = 24
• Crop type → Oilseed crop
• Season → Rabi
• Pollination → Mostly self-pollinated
• Inflorescence → Capitulum
• Fruit type → Achene
• Oil content → 28–35%
• Oil quality → Rich in linoleic acid
• Root system → Deep tap root (up to 2 m)
• Drought tolerance → Very high
• Sensitive to → Waterlogging
• Climate → Cool season crop
• Ideal temperature → 20–30°C
• Rainfall requirement → 300–600 mm
• Best soil → Deep black soils
• pH tolerance → 6.0–8.5
• Seed rate → 10–15 kg/ha
• Spacing → 45 × 20 cm
• Critical stages → Flowering and seed filling
• Crop duration → 120–140 days
• Major pest → Aphids
• Major disease → Alternaria leaf spot
• Spiny leaves reduce → Grazing damage
• Petals used as → Natural dye
• Oilcake used as → Cattle feed
• Major cropping system → Sorghum–Safflower
• Highly suited for → Residual moisture conditions
• Harvest when → Heads turn brown
• Yield → 8–12 q/ha
• Also called → Kusum