Sunflower (Helianthus annus)
Chromosome number: 17
- Sunflower is an oil seed crop.
- Sunflower oil that is derived from its seed is a major source of vegetable oil in the world.
- Sunflower crop is also used as an ornamental crop in many countries.
- Sunflower is a short duration crop.
- Commercial production of sunflower began in 1972.
- Sunflower crop is a great source to be used as a silage crop that can be fed to animals.
- Sunflower crop oil has many health benefits as it
- Sunflower oil contains linoleic fatty acids, vitamin E, magnesium, etc.
- Sunflower is a photo insensitive crop.
- Sunflower crop does not primarily require any specific season to grow, it can be grown in any season. It is also a short duration crop.
Area and Distribution
- Area under cultivation – 26 million hectares.
- European Union, Russia, Ukraine, Argentina, United States, China, India and Turkey are the major producers of sunflower in the world .
- Russia is the largest producer of Sunflower.
- Ukraine stands at the second position in sunflower production.
- Sunflower crop is cultivated commercially in many states of India like
Karnataka, Andhra Pradesh, Maharashtra and Tamil Nadu
- It can be grown on a variety of soils ranging from sandy loam to heavy clay soils.
- Sunflower crop cannot withstand even short period of waterlogging.
- Sunflower crop requires well prepared seedbed for optimum seed germination, stand establishment and growth.
- In the case of light soils, two ploughing followed by harrowing and planking is optimum.
- Medium and heavy soils are prepared by harrowing twice or thrice when the soil moisture is optimum for tillage operations.
- Sunflower can thrive in slightly acidic to somewhat alkaline soil.
- Soil pH should be 6.0 to 7.5.
Climate and Temperature
- Sunflower crop requires cool climate during germination.
- However sunflower crop grows well in warm weather.
- Its seed can germinate at 40 degree C but optimum temperature for seed germination ranges from 8 to 10 degree C.
- Ideal temperature for fruit set is 21 to 24 degree C.
- More number of seeds are obtained at temperature ranging from 24 to 26 degree C during daytime and 18 to 20 degree C during night.
- Sunflower crops prefers bright sunlight there it should not be grown in shady areas.
- Optimum rainfall requirement is 500 to 750 mm for better seed yield.
- Although sunflower crop could be grown throughout the year.
- For normal varieties
- For Hybrid
Method of seeding
- Seed should be soaked in water for 14 hours followed by shade drying for quick and better germination.
- Seed could be treated with Thiram or Captan 2-3 g/Kg, it gives protection from seed borne diseases.
- Line sowing using seed drill is considered as the best method of sowing.
- Hand dibbling in plough furrows is also common.
- Optimum seeding depth is 5 cm.
- Optimum Row to row spacing ranges from 45-100 cm. with plant population density of 60,000 to 2,50,000 plants/ha.
- However spacing varies in hybrid as it requires wider row spacing of 60 cm.
- Application of FYM( Farm Yard Manure) @10 t/ha is considered good.
- Fifty per cent of the recommended nitrogen and entire dose of phosphorus and potassium should be applied at sowing.
- In the case of rainfed sunflower crop, top dress the remaining nitrogen around 30 DAS depending on rainfall.
- In the case of irrigated sunflower crop, 25 per cent of the remaining nitrogen should be applied in two equal parts 30 DAS (button stage) and 55 DAS (flowering stage).
- Apply NPK fertilizers as per soil test recommendations. if recommendation is not available follow the following NPK/ha doze recommendation:
Season Blanket recommendation of Nutrients (kg/ha) N P2O5 K2O Hybrids Irrigated 60 90 60 Rainfed 40 50 40 Varieties Irrigated 60 30 30 Rainfed 40 50 40
- Depending on soil, weather conditions and other factors water requirement varies as given in the following data:
- Sunflower crop is affected by both heavy and light irrigation.
- Irrigate immediately after sowing
- During growth days, irrigate at an interval of 7 to 8 days in case of light soil.
- In heavy soils water should be applied at an interval of 15 to 20 days
- Pre sowing,
- 20 DAS,
- During early bud development,
- During flowering it requires 2 irrigations,
- Seed development – 2 irrigations.
- Major weeds found in sunflower crops are:
- Cyperus rotundus
- Corchorus olitorius
- Celocia argentina
- Amaranthus viridis
- Chloris barbata
- Remove the weeds with the help of hoe or do hand weeding on 15th or 30th DAS.
- Apply Fluchloralin @2 L/ha before sowing. Also apply this as pre emergence spray at 5th day after sowing followed by irrigation.
- Depending on season sunflower crop is ready to be harvested in :
- 90 days in Kharif, 105 – 130 days in Rabi and 100 – 110 days in spring season.
- Harvesting should be done when back of the head turns from green to lemon yellow color and the bottom leaves starts drying.
- Mechanical thresher is used to separate seeds from flower.
- Avoid harvesting during rainy or cloudy weather condition.
- Yield varies between crop grown during the rain-fed and irrigated conditions.
- In the rainfed condition, crop grain yield is 300 to 500 Kg per hectare.
- In irrigated condition crop grain yield is 800 to 1200 Kg per hectare.