sunflower🌻

• Common sunflower


  Species of large annual forb of the daisy family Asteraceae
• Helianthus annuus


  • Harvested for its edible oily seeds which are used in the production of cooking oil
  • Variety of purposes e.g. food for livestock, bird food, and planted in domestic gardens for aesthetics
  • Known for its multiple flower heads, whereas the domestic sunflower often possesses a single large flower head atop an unbranched stem
• The plant was first domesticated in the Americas
• Sunflower seeds were brought to Europe from the Americas in the 16th century, where, along with sunflower oil, they became a widespread cooking ingredient
• As of 2020, Russia and Ukraine together produce over half of worldwide seed production
• Heliotropism


  Immature flower buds exhibit this behaviour, where the flower heads track the Sun across the sky<|>Mature flowering heads point in a fixed (and typically easterly) direction throughout the day
• The uniform alignment of sunflower heads in a field might give some people the false impression that the flowers are tracking the Sun
• Floret arrangement


  Generally, each floret is oriented toward the next by approximately the golden angle, 137.5°, producing a pattern of interconnecting spirals, where the number of left spirals and the number of right spirals are successive Fibonacci numbers
• The pattern produces the most efficient packing of seeds mathematically possible within the flower head
• Genome


  The sunflower genome is diploid with a base chromosome number of 17 and an estimated genome size of 2,871–3,189 million base pairs
• Some sources claim its true size is around 3.5 billion base pairs (slightly larger than the human genome)
• Sunflowers grow best in fertile, moist, well-drained soil with heavy mulch
• Outside of cultivation, the common sunflower is found on moist clay based soils in areas with climates similar to Texas
• The precise native range is difficult to determine, but it is native to parts of the Western United States and Mexico
• Sunflowers can now be found in almost every part of the world that is not tropical, desert, or tundra
• The common sunflower is native to the Western United States and Canada, though it can now be found in almost every part of the world that is not tropical, desert, or tundra
• One of the major threats that sunflowers face today is Fusarium, a filamentous fungus that is found largely in soil and plants, which has caused up to 80% damage to sunflower crops
• Downy mildew is another disease to which sunflowers are susceptible, particularly due to their shallow planting
• Another major threat to sunflower crops is broomrape, a parasite that attacks the root of the sunflower and can cause up to 100% damage
• Commercial planting of sunflowers

  Seeds are planted 45 cm (1 1/2 ft) apart and 2.5 cm (1 in) deep
• Sunflowers were first domesticated in Mexico


  2600 BCE
• Earliest known examples of fully domesticated sunflowers found in Tennessee

  2300 BCE
• The sunflower is currently the most economically important of the four plants known to have been domesticated in eastern North America
• Research indicates there was a single domestication event of sunflowers in central North America, and they may have gone through significant bottlenecks dating back to ~5,000 years ago
• First crop breeds of sunflowers were brought from America to Europe by explorers


  16th century
• Domestic sunflower seeds have been found in Mexico

  2100 BCE
• Native American people grew sunflowers as a crop from Mexico to Southern Canada
• The Russian Empire reintroduced sunflower oilseed cultivation to North America in the mid-20th century, starting North America's commercial era of sunflower production and breeding
• Sunflower oil became very popular in Russia, particularly with members of the Russian Orthodox Church, during the 18th century due to fasting traditions
• In the early 19th century, sunflower oil was first commercialized in the village of Alexeyevka in Voronezh Governorate by the merchant Daniil Bokaryov
• In 2020, world production of sunflower seeds was 50 million tonnes, led by Russia and Ukraine with 53% combined
• Ammonium nitrate was found to produce better nitrogen absorption in sunflowers than urea, which performed better in low-temperature areas
• Sunflower cultivation typically uses crop rotation, often with cereals, soybean, or rapeseed, to reduce idle periods and increase total sunflower production and profitability
• Hybrid sunflowers


  Produced by cross-breeding different types and species, generally have higher fitness and desired properties like pathogen resistance
• Hybrid Helianthus annuus dwarf2

  Does not contain the hormone gibberellin and does not display heliotropic behavior
• Hybrid male sterile and male fertile sunflowers have a low crossover of honeybee visitation, likely due to sensory cues like pollen odor, seed head diameter, and height
• Cultivars of sunflowers

  • American Giant
  • Arnika
  • Autumn Beauty
  • Aztec Sun
  • Black Oil
  • Chianti Hybrid
  • Claret
  • Dwarf Sunspot
  • Evening Sun
  • Florenza
  • Giant Primrose
  • Gullick's Variety
  • Incredible
  • Indian Blanket Hybrid
  • Irish Eyes
  • Italian White
  • Kong Hybrid
  • Large Grey Stripe
  • Lemon Queen
  • Loddon Gold
  • Miss Mellish
  • Monarch
  • Mongolian Giant
  • Moon-Walker
  • Munchkin
  • Orange Sun
  • Pastiche
  • Peach Passion
  • Peredovik
  • Prado Red
  • Red Sun
  • Ring of Fire
  • Rostov
  • Russian Giant
  • Skyscraper
  • Solar Eclipse
  • Soraya
  • Strawberry Blonde
  • Sunny Hybrid
  • Sunsation Yellow
  • Sunshine
  • Taiyo
  • Tarahumara
  • Teddy Bear
  • Thousand Suns
  • Titan
  • Valentine
  • Velvet Queen
  • Yellow Disk
  • Prado Red
  • Mammoth Russian
  • Teddy Bear
• Uses of sunflowers


  • Snack food (raw or roasted)
  • Sunflower butter
  • Bird food
  • Cooking and salads
  • Bread, medical ointments, dyes and body paints (for Native Americans)
  • Sunflower oil for cooking, as a carrier oil, to produce margarine and biodiesel
  • Livestock feed (from seed cake and hulls)
  • Ornamental plants
  • Latex production and hypoallergenic rubber experiments
  • Allelopathic properties
  • Hair dressing
  • Snakebite treatment (for Zuni people)
  • Weed (for commercial farmers of other crops)
• Sunflowers can be used in phytoremediation to extract pollutants like lead and heavy metals from soil, and in rhizofiltration to neutralize radionuclides from ponds after nuclear disasters
• Sunflowers are depicted in art, such as by Anthony van Dyck and Vincent van Gogh, and have symbolic meaning in Iroquois mythology