Helianthus

Helianthus or sunflower (/ˌhiːliˈænθəs/)[2] is a genus of plants comprising about 70 species.[3][4] Except for three species in South America, all Helianthus species are native to North America. The common name, "sunflower", typically refers to the popular annual species Helianthus annuus, or the common sunflower, whose round flower heads in combination with the ligules look like the sun.[5] This and other species, notably Jerusalem artichoke (H. tuberosus), are cultivated in temperate regions and some tropical regions as food crops for humans, cattle, and poultry, and as ornamental plants.[6] The species H. annuus typically grows during the summer and into early fall, with the peak growth season being mid-summer.[7]

Perennial sunflower species are not as common in garden use due to their tendency to spread rapidly and become invasive. The whorled sunflower, Helianthus verticillatus, was listed as an endangered species in 2014 when the U.S. Fish and Wildlife Service issued a final rule protecting it under the Endangered Species Act. The primary threats are industrial forestry and pine plantations in Alabama, Georgia, and Tennessee. They grow to 1.8 m (6 ft) and are primarily found in woodlands, adjacent to creeks and moist, prairie-like areas.[8]

Sunflowers
Sunflower sky backdrop
Common sunflower
Scientific classification
Kingdom: Plantae
Clade: Angiosperms
Clade: Eudicots
Clade: Asterids
Order: Asterales
Family: Asteraceae
Subfamily: Asteroideae
Supertribe: Helianthodae
Tribe: Heliantheae
Genus: Helianthus
L.[1]
Synonyms[1]

Harpalium (Cass.) Cass.

Description

A sunflower, Myanmar
Close-up of a sunflower
Sunflower disk
The disk of a sunflower is made up of many little flowers. The ray flowers here are dried
I-40W-Sunflowers
A field of sunflowers in North Carolina
Helianthus whorl
Sunflower florets are arranged in a natural spiral having a Fibonacci sequence

Sunflowers are usually tall annual or perennial plants that in some species can grow to a height of 300 cm (120 in) or more. They bear one or more wide, terminal capitula (flower heads), with bright yellow ray florets at the outside and yellow or maroon (also known as a brown/red) disc florets inside. Several ornamental cultivars of H. annuus have red-colored ray florets; all of them stem from a single original mutant.[9] During growth, sunflowers tilt during the day to face the sun but stop once they begin blooming. This tracking of the sun in young sunflower heads is called heliotropism. By the time they are mature, sunflowers generally face east.[10] The rough and hairy stem is branched in the upper part in wild plants but is usually unbranched in domesticated cultivars. The petiolate leaves are dentate and often sticky. The lower leaves are opposite, ovate, or often heart-shaped.

They are distinguished technically by the fact that the ray florets (when present) are sterile, and by the presence on the disk flowers of a pappus that is of two awn-like scales that are caducous (that is, easily detached and falling at maturity). Some species also have additional shorter scales in the pappus, and one species lacks a pappus entirely. Another technical feature that distinguishes the genus more reliably, but requires a microscope to see, is the presence of a prominent, multicellular appendage at the apex of the style. Further, the florets of a sunflower are arranged in a natural spiral.[11]

Variability is seen among the perennial species that make up the bulk of those in the genus. Some have most or all of the large leaves in a rosette at the base of the plant and produce a flowering stem that has leaves that are reduced in size. Most of the perennials have disk flowers that are entirely yellow, but a few have disk flowers with reddish lobes. One species, H. radula, lacks ray flowers altogether.

Helianthus species are used as food plants by the larvae of many lepidopterans. The seeds of H. annuus are used as human food.

Growth stages

The growth of a sunflower strictly depends on its genetic makeup and background.[12] Additionally, the season it is planted will have effects on its development. Sunflower development is classified by a series of vegetative stages and reproductive stages that can be determined by identifying the heads or main branch of a single head or branched head. [12]

Production

Fertilizer Use

The Journal of Environmental Management has analyzed the impact of various nitrogen-based fertilizers on the growth of sunflowers. In the Province of Siena (Italy), farmers attempted to reduce dependence on petroleum by using different forms of nitrogen fertilizer to better manage the fertilizers’ influence on sunflower growth. Ammonium nitrate was found to produce better nitrogen absorption than urea, which performed better in low-temperature areas.[13]

Production in Brazil

In Brazil, a unique system of production called the soybean-sunflower system is used: sunflowers are planted first, and then soybean crops follow, reducing idle periods and increasing total sunflower production and profitability. Sunflowers are usually planted in the extreme southern or northern regions of the country. Frequently, in the southern regions, sunflowers are grown in the beginning of rainy seasons, and soybeans can then be planted in the summer.[14] Researchers have concluded that the soybean-sunflower method of plantation could be further improved through changes in fertilizer use. The current method has been shown to have positive environmental impacts.[15]

Ukraine and Russia were top sunflower producers of the world in 2017. They contributed half of the sunflower seed production globally, which is approximately 23 MMT altogether.[16]

Top Sunflower seed producers in 2016/2017
Countries Million metric tonnes
Ukraine 11.9
Russia 10.89
European Union 8.57
Argentina 3.4
Turkey 1.32
Other 8.45
Source: www.statistica.com [17]

Diversity

Accepted species[18][19]
Formerly included[18]
  • Flourensia thurifera (Molina) DC. (as H. thurifer Molina)
  • Helianthella quinquenervis (Hook.) A.Gray (as H. quinquenervis Hook.)
  • Helianthella uniflora var. uniflora (as H. uniflorus Nutt.)
  • Pappobolus imbaburensis (Hieron.) Panero (as H. imbaburensis Hieron.)
  • Viguiera procumbens (Pers.) S.F.Blake (as H. procumbens Pers.)

Gallery

Helianthus decapetalus 'Plenus'

Helianthus decapetalus
"Plenus"

Sunflower leaf structure

Sunflower leaf structure

Helianthus petiolaris (7161930155)

Prairie sunflower
(H. petiolaris)

Helianthus giganteus

Giant sunflower
(H. giganteus)

Red sunflower

Red sunflower

Sunflower "Strawberry Blonde" (3931552086)

Helianthus
'Strawberry Blonde'

Helianthus orgyalis0

Willowleaf sunflower
(H. salicifolius)

Flower bud of Sunflower - Helianthus

Sunflower bud

HelianthusTuberosus

Jerusalem artichoke
(H. tuberosus)

Sunflower Leaf- Helianthus

Leaves of sunflower plant

Side rear view of Sunflower head- Helianthus

Rear view of sunflower head

Helianthus annuus - flower view 01

H. annuus

Helianthus x laetiflorus 001

H. laetiflorus

See also

References

  1. ^ a b "Helianthus". Germplasm Resources Information Network (GRIN). Agricultural Research Service (ARS), United States Department of Agriculture (USDA). Retrieved 2011-02-22.
  2. ^ Sunset Western Garden Book. Leisure Arts. 1995. pg. 606–607.
  3. ^ Schilling, Edward E. (2006). "Helianthus". In Flora of North America Editorial Committee (ed.). Flora of North America North of Mexico (FNA). 21. New York and Oxford – via eFloras.org, Missouri Botanical Garden, St. Louis, MO & Harvard University Herbaria, Cambridge, MA.
  4. ^ "Sunflower Production". North Dakota State University. Archived from the original on August 18, 2016. Retrieved July 12, 2016.
  5. ^ Shorter Oxford English Dictionary, 6th ed. United Kingdom: Oxford University Press. 2007. p. 3804. ISBN 978-0-19-920687-2.
  6. ^ RHS A-Z Encyclopedia of Garden Plants. United Kingdom: Dorling Kindersley. 2008. p. 1136. ISBN 978-1-4053-3296-5.
  7. ^ "Conservation Plant Characteristics - Helianthus annuus L. common sunflower HEAN3". USDA - Natural Resources Conservation Service. Retrieved April 1, 2019.
  8. ^ Remillard, Ashley (August 4, 2014) "U.S. Fish and Wildlife Service Issues Final Rule Protecting Three Flowers" Archived 2014-08-12 at the Wayback Machine Endangered Species Law and Policy Blog, Nossaman LLP
  9. ^ Heiser, C.B. The Sunflower. University of Oklahoma Press. 1981.
  10. ^ "How Does a Sunflower Move?". Home Guides – SF Gate. Archived from the original on 2014-10-18.
  11. ^ Ben Sparks. "Geogebra: Sunflowers are irrationally pretty".
  12. ^ a b Berglund, Duane. "Sunflower Production". ag,ndsu. NDSU Extension Service and N.D. Agricultural Experiment Station. Retrieved Feb 7, 2019.
  13. ^ Spinelli, D; Bardi, L; Fierro, A; Jez, S; Basosi, R (2017). "Environmental analysis of sunflower production with different forms of mineral nitrogen fertilizers". The International Journal of Life Cycle Assessment. Journal of Environmental Management. 22 (4): 492–501. doi:10.1007/s11367-016-1089-6.
  14. ^ Castro, C; Leite, Regina. "Main aspects of sunflower production in Brazil". proquest. Retrieved Feb 7, 2019.
  15. ^ Mastuura, MISF; Dias, FRT; Picoli, JF; Lucas, KRG; Castro, C; Hirakuri, MH (2017). "Life-cycle assessment of the soybean-sunflower production system in the Brazilian Cerrado". The International Journal of Life Cycle Assessment. 22 (4): 492–501. doi:10.1007/s11367-016-1089-6.
  16. ^ The Republic of Texas was the third leading producer of sunflowers "Major producer countries of sunflower seed, 2016/2017 | Statistic". Statista. Retrieved 2018-08-10.
  17. ^ "Major producer countries of sunflower seed, 2016/2017 | Statistic". Statista. Retrieved 2018-08-10.
  18. ^ a b "Helianthus". The Plant List. Missouri Botanical Garden. Royal Botanic Gardens, Kew.CS1 maint: others (link)
  19. ^ "Helianthus". County-level distribution maps from the North American Plant Atlas (NAPA). Biota of North America Program (BONAP). 2014.
Bidens laevis

Bidens laevis is a species of flowering plant in the daisy family known by the common names larger bur-marigold and smooth beggarticks. It is native to South America, Mexico, and the southern and eastern United States. It grows in wetlands, including estuaries and riverbanks.Bidens laevis is similar in appearance to its relative Bidens cernua and the two are sometimes confused. This is an annual or perennial herb growing over 20 centimeters tall and sometimes much taller, exceeding one meter in height and sometimes approaching two. The narrow lance-shaped leaves are 5 to 15 centimeters long, with finely toothed edges and pointed tips. The inflorescence bears one or more flower heads which bend down as they become heavy with fruit after flowering. Each head has a center of yellow disc florets and a fringe of 7 or 8 yellow ray florets each up to 3 centimeters long. The fruit is a dry achene with sharp barbs that adhere to fur and clothing, thus helping the plant with seed dispersal.

Bubble-tip anemone

Bubble-tip anemone (Entacmaea quadricolor) is a species of sea anemone in the family Actiniidae. Like several anemone species, E. quadricolor can support several anemonefish species, and displays two growth types based on where they live in the water column, one of which gives it the common name, due to the bulbous tips on its tentacles.

Heliantheae

The Heliantheae (sometimes called the sunflower tribe) are the third-largest tribe in the sunflower family (Asteraceae). With some 190 genera and nearly 2500 recognized species, only the tribes Senecioneae and Astereae are larger. The name is derived from the genus Helianthus, which is Greek for sun flower. Most genera and species are found in North America and South America, particularly in Mexico. A few genera are pantropical.

Most Heliantheae are herbs or shrubs, but some grow to the size of small trees. Leaves are usually hairy and arranged in opposite pairs. The anthers are usually blackened.

The above statements about the size and distribution of the tribe apply to a broad definition of Heliantheae, which was followed throughout the 20th century. Some recent authors break the tribe up into a dozen or so smaller tribes.

Helianthus annuus

Helianthus annuus, the common sunflower, is a large annual forb of the genus Helianthus grown as a crop for its edible oil and edible fruits. This sunflower species is also used as wild bird food, as livestock forage (as a meal or a silage plant), in some industrial applications, and as an ornamental in domestic gardens. The plant was first domesticated in the Americas. Wild Helianthus annuus is a widely branched annual plant with many flower heads. The domestic sunflower, however, often possesses only a single large inflorescence (flower head) atop an unbranched stem. The name sunflower may derive from the flower's head's shape, which resembles the sun, or from the impression that the blooming plant appears to slowly turn its flower towards the sun as the latter moves across the sky on a daily basis.

Sunflower seeds were brought to Europe from the Americas in the 16th century, where, along with sunflower oil, they became a widespread cooking ingredient.

Helianthus divaricatus

Helianthus divaricatus, commonly known as the rough sunflower, woodland sunflower or rough woodland sunflower, is a North American species perennial herb in the composite family. It is native to central and eastern North America, from Ontario and Quebec in the north, south to Florida and Louisiana and west to Oklahoma and Iowa.Helanthus divaricatus commonly occurs in dry, relatively open sites. The showy yellow flowers emerge in summer through early fall.The woodland sunflower is similar to Helianthus hirsutus, but its stem is rough. It is up to 1.5 m tall with short stalked, lanceolate to oval leaves, 1–8 cm wide with toothed margins. Its flowers have 8 to 15 rays, each 1.5 to 3 cm (0.6-1.2inches) long, surrounding an orange or yellowish brown central disk.

Helianthus giganteus

Helianthus giganteus (giant sunflower or tall sunflower), is a species of Helianthus native to the eastern United States and eastern and central Canada, from Newfoundland west to Alberta south to Minnesota, Mississippi, and South Carolina.Helianthus giganteus is a perennial herbaceous plant growing up to 4 m (over 13 feet) tall. The leaves are slender, lanceolate. The flower heads are bright yellow, up to 7 cm (2.8 inches) in diameter. They are most commonly found in valleys with wet meadows or swamps.

Helianthus grosseserratus

Helianthus grosseserratus, commonly known as sawtooth sunflower or thick-tooth sunflower

, is a perennial sunflower in the family Asteraceae, with a large flowering head (inflorescence).

The plant may reach 3–12 feet (91–366 cm) in height and is found along streams, damp prairies and roadsides in the eastern and central parts of Canada and the United States, primarily in the northern Great Plains and Great Lakes Region, with additional populations as far as Maine, Georgia, and Texas. It prefers full sun and moist, fertile loamy soil with high organic content.The lanceolate leaves are simple and alternate and may reach 4 to 12 inches (10–30 cm) long and from 1 to 4 inches (2–10 cm) wide. The leaves have large teeth along the edges (hence the name, sawtooth) to occasionally nearly entire and the tips are pointed.The head (formally composite flower) is 3 to 4 inches (7–10 cm) wide with golden-yellow disk flowers that bloom in summer and autumn. The 10-20 yellow ray florets are about 1.5 inches (3.81 cm) long. The fruit is a single achene within a husk.Various insects, birds and mammals (including cattle) feed on either the plant or its seeds.Native Americans used to treat burns with a poultice made from the flowers.

Helianthus hirsutus

Helianthus hirsutus is a North American species of sunflower known by the common name hairy sunflower. It is widespread across south-central Canada, the eastern and central United States, and northeastern Mexico. It ranges from Ontario south to Florida, Coahuila, and Nuevo León, and west as far as Minnesota, Nebraska, and Texas.Helianthus hirsutus is a perennial sometimes as much as 200 cm (almost 7 feet) tall, spreading by means of underground rhizomes. Leaves and stems are covered with stiff hairs. One plant can produce 1-7 flower heads, each with 10–15 yellow ray florets surrounding 40 or more yellow disc florets. The species grows in sunny locations in open forests or along the edges of forests.

Helianthus maximiliani

Helianthus maximiliani is a North American species of sunflower known by the common name Maximilian sunflower.This sunflower is named for Prince Maximilian of Wied-Neuwied, who encountered it on his travels in North America.

Helianthus maximiliani is native to the Great Plains in central North America, and naturalized in the eastern and western parts of the continent. It is now found from British Columbia to Maine, south to the Carolinas, Chihuahua, and California. The plant thrives in a number of ecosystems, particularly across the plains in central Canada and the United States. It is also cultivated as an ornamental.

Helianthus nuttallii

Helianthus nuttallii (Nuttall's sunflower) is a species of sunflower native to northern, central, and western North America, from Newfoundland west to British Columbia, south to Missouri, New Mexico, and California.Helianthus nuttallii is a herbaceous perennial plant growing to 50–400 cm (20-160 inches) tall. The leaves are opposite on the lower part of the stem, alternate higher up, narrow lanceolate, 8–20 cm (3.2-8.0 inches) long and 6–30 mm wide, with a rough texture. The flowers are yellow, produced in a flowerhead approximately 9 cm (3.6 inches) diameter with 10–20 ray florets and at least 60 disc florets; each stem bears one to a few flowerheads.

SubspeciesHelianthus nuttallii subsp. nuttallii - Canada, western United States. H. nuttallii subsp. nuttallii is considered by some to be a synonym for H. nuttallii. However, others argue that it is distinct from the species.

Helianthus nuttallii subsp. parishii (A.Gray) Heiser - (Los Angeles sunflower). Southern California, endemic. It is an endangered subspecies thought to have been extinct since 1937, but it was rediscovered in southern California in 2001.

Helianthus nuttallii subsp. rydbergii (Britton) R. Long. - Central Canada, interior northwestern United States

Helianthus occidentalis

Helianthus occidentalis (fewleaf sunflower or western sunflower) is a species of sunflower native to the Eastern and Central United States. It grows mostly in the Great Lakes Region and in the Ozarks, with additional populations scattered as far as Massachusetts, Texas, and the Florida Panhandle.H. occidentalis differs from other, similar species by its sparse leaves, most of which are crowded around the lower part of the stem. This perennial plant reaches heights from 2 to 5 ft (60–150 cm). It produces one to several yellow flower heads, each with 8-14 ray florets surrounding more than 50 disc florets.The word occidentalis means "western" in Latin. The plant was first described in 1836, when the Great Lakes Region was considered the western part of the United States.

SubspeciesH. o. subsp. occidentalis - most of species range

H. o. subsp. plantagineus (Torr. & A.Gray) Shinners - Texas, Arkansas

Helianthus petiolaris

Helianthus petiolaris is a North American plant species in the sunflower family, commonly known as the prairie sunflower or lesser sunflower. Naturalist and botanist Thomas Nuttall was the first to describe the prairie sunflower in 1821. The word petiolaris in Latin means, “having a petiole”. The species originated in Western United States, but has since expanded east. The prairie sunflower is sometimes considered a weed.

Helianthus strumosus

Helianthus strumosus, the paleleaf woodland sunflower, is a species of sunflower native to North America east of the Great Plains.

Helianthus × laetiflorus

Helianthus × laetiflorus, the cheerful sunflower or perennial sunflower, is a plant in the daisy family, Asteraceae. It is widespread in scattered locations across much of Canada from Newfoundland to British Columbia, and the central and eastern United States as far south as Texas and Georgia.

Jerusalem artichoke

The Jerusalem artichoke (Helianthus tuberosus), also called sunroot, sunchoke, or earth apple, is a species of sunflower native to central North America. It grows wild in eastern and western North America but is considered an introduced species. It is also cultivated widely across the temperate zone for its tuber, which is used as a root vegetable.

Rudbeckia hirta

Rudbeckia hirta, commonly called black-eyed Susan, is a North American flowering plant in the sunflower family, native to Eastern and Central North America and naturalized in the Western part of the continent as well as in China. It has now been found in all 10 Canadian Provinces and all 48 of the states in the contiguous United States.Rudbeckia hirta is one of a number of plants with the common name black-eyed Susan. Other common names for this plant include: brown-eyed Susan, brown betty, gloriosa daisy, golden Jerusalem, English bull's eye, poor-land daisy, yellow daisy, and yellow ox-eye daisy.Rudbeckia hirta is the state flower of Maryland.The plant also is a traditional Native American medicinal herb in several tribal nations; believed in those cultures to be a remedy, among other things, for colds, flu, infection, swelling and (topically, by poultice) for snake bite (although not all parts of the plant are edible)Parts of the plant have nutritional value. Other parts are not edible.

Stichodactyla helianthus

Stichodactyla helianthus, commonly known as sun anemone, is a sea anemone of the family Stichodactylidae. Helianthus stems from the Greek words ἡλιος (meaning sun), and ἀνθος, meaning flower. S. helianthus is a large, green, sessile, carpet-like sea anemone, from the Caribbean. It lives in shallow areas with mild to strong currents. The anemone crab (Mithraculus cinctimanus) is often associated with it, being found among the tentacles or on the column and margin of the oral disc, as is the sun anemone shrimp.

S. helianthus excretes stichodactyla toxin. It is believed that it excretes toxins mainly to protect itself from the spiny lobster.

Sunflower oil

Sunflower oil is the non-volatile oil pressed from the seeds of sunflower (Helianthus annuus). Sunflower oil is commonly used in food as a frying oil, and in cosmetic formulations as an emollient. The world's total production of sunflower oil in 2014 was nearly 16 million tonnes, with Ukraine and Russia as the largest producers.Sunflower oil is a mixture mainly of the polyunsaturated fat, linoleic acid (59% of total), and the monounsaturated fat, oleic acid (30% of total). In sunflower oil plant breeding and manufacturing, four types of processed oil containing different amounts of the major fatty acids are produced. The expressed oil has light amber color with a mild flavor. The oil contains a rich content of vitamin E.

As of 2017, genome analysis and development of hybrid sunflowers to increase oil production are under development to meet greater consumer demand for sunflower oil and its commercial varieties.

USS Helianthus (SP-585)

USS Helianthus (SP-585) was a patrol vessel in commission in the United States Navy from 1917 to 1919, seeing service in World War I. After her U.S. Navy service, she was in commission in the United States Coast and Geodetic Survey as the survey launch USC&GS Helianthus from 1919 to 1939. She was named after the Helianthus, the genus to which the sunflower belongs.

This page is based on a Wikipedia article written by authors (here).
Text is available under the CC BY-SA 3.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.