Oenothera

Common Evening Primrose (Oenothera biennis ), illustration

The evening primrose (Oenothera ) are a genus of the Onagraceae family ( Onagraceae ). It contains about 120 to 200 species. Originally Evening primrose species were widespread in North America. In the 17th century they were introduced as ornamental plants into Europe. They are feral and neophytes as a permanent part of the Central European flora.

• 5.1 Notes and references

Dissemination

They are originally from the temperate regions of North, Central and South America. The center of diversity is the south-western North America. Many species have become naturalized in many other countries.

Description

Vegetative characteristics

Evening primrose species are one-, two-year and perennial herbaceous plants. Some species form rhizomes as outlasting. Some species form taproots. The simple leaves are in a basal rosette or distributed, alternate and spirally on the stem. The leaf margin is smooth to lobed. Stipules absent.

Generative features

The flowers are individually together in the leaf axils or in differently constructed inflorescences. The hermaphrodite, radial symmetry flowers are cruciform with a double perianth. The four green to yellowish sepals often have a red or purple-colored drawing and have grown Roehrig. The four free petals are white, yellow or pink to purple. There are two circles, each with four stamens present. The four carpels are fused to an under standing, vierfächerigen ovary, which contains many ovules. The scar is vierlappig.

There are pedunculated or sessile capsule formed fruit with many seeds.

Chromosome numbers of 2n = 14, 28, 42, 56 have been found.

Ecology

Most species are pollinated by nocturnal insects and therefore only smell at night. The nectar in the flower tubes under constant is only available to langrüsselige insects. Especially often found on the flowers representative of a moth ( butterfly ). How can the flowers such as the Hummingbird Hawk and the Middle Hawk-moth watch them as they stand in front of the flowers in Schwirrflug. A Schwärmerart even carries the name evening primrose enthusiasts because of their preference for the nectar of this plant genus.

The individual flowers are very short-lived. They open only at dusk and are mostly faded until noon the next day again. The exact date on which the flower is open, depending on the position of the sun, of the daily temperature and the humidity.

The opening of the flowers is often done within a few minutes in one fluid motion. The rapidity with which the flowering is done is to observe with any other occurring in Central Europe plant.

A blooming flowers is usually still odorless. Only after its fully open their fragrance is intensely sweet, so that it is sometimes perceived by people as intrusive and almost fetid.

The evening primrose produce hundreds of seeds. The seed compartments open as soon as the plant has died. Even the vibrations by light winds are sufficient to disperse the seeds.

The two-year evening primrose species bloom in the second year. In the first year a flat lying on the floor sheet plate forms. In the second year the plant develops up and developed the flower stems that can reach up to 2 meters Height.

Evening primrose are very diverse and often dominant in developed ruderal companies that are on dry and sunny ( warm ) locations. Since these biennial plants are displaced after a few years of perennials without further disturbance of the soil, the deposits are often sporadic.

System

The genus name Oenothera was first published in 1753 by Carl Linnaeus in Species Plantarum, 1, p 346. Synonyms for Oenothera L. are: Anogra Spach, Baumannia Spach, Blennoderma Spach, Calylophis Spach orth var, Calylophus Spach, Galpinsia Britton, Gaura L., Gaurella Small, Gauridium Spach, Gauropsis C.Presl, Gauropsis ( Torr. & Frem. ) Cockerell, Hartmannia Spach, Kneiffia Spach, Lavauxia Spach, Megapterium Spach, Meriolix Raf. ex Endl. , Onagra Mill, Onosuris Raf., Onosurus G.Don orth var, Pachylophus Spach, Peniophyllum Pennell, Raimannia Rose, Salpingia ( Torr. & A. Gray ) Raim. , Schizocarya Spach, Stenosiphon Spach, Usoricum Lunell, Xylopleurum Spach; some of them now have the rank of sections or subsections. Type species is Oenothera biennis L..

As a special note, created by cross-breeding in Central Europe spontaneously or in cultural hybrids that do not exist in the original home of the evening primrose. The newly formed hybrids behave like independent populations and are therefore regarded as species.

The genus Oenothera belongs to the tribe Onagreae in the subfamily Onagroideae in the family Onagraceae. The genus Oenothera is divided into 18 sections.:

• Section Anogra
• Section Calylophus: Under section Calylophus
• Under section Salpingia

• Under section Campogaura
• Under section Gaura
• Under section Gauridium
• Under section Schizocarya
• Under section Stenosiphon
• Under section Stipogaura
• Under section Xenogaura
• Under section Xerogaura

• Under section Australis
• Under section Lavauxia

• Under section Candela
• Under section Emersonia
• Under section Munzia (Series: Allochroa, Clelandia, Renneria )
• Under section Nutantigemma
• Subsection Oenothera
• Under section Raimannia

Among the 120 to 200 evening primrose species include:

• Oenothera acaulis Cav, home. Chile
• Oenothera affinis Cambess.
• Oenothera ammophila Focke
• Shalebarren Evening Primrose (Oenothera argillicola Mackenzie )
• Oenothera atrovirens Shull & Bartlett
• Naturalized in North America Europe, Middle East and New Zealand: Common Evening Primrose (Oenothera biennis L.), home
• Oenothera chicagoensis Renner ex RECleland & Blakeslee
• Oenothera clelandii W. Dietr., P.H. Raven, W. L. Wagner
• Oenothera coronifera Renner
• Oenothera drummondii Hooker, Origin: Texas, Mexico
• Oenothera fruticosa L., Origin: North America
• Rotkelchige night candle or Red Striped Evening primrose ( Oenothera glazioviana Micheli, Syn: Oenothera erythrosepala Borbás, Oenothera lamarckiana Ser. ), Home unknown, naturalized in Europe and North America
• Large-flowered Evening Primrose (Oenothera grandiflora L' Hér. )
• Oenothera grandis ( Britton ) Smyth
• Oenothera heterophylla Spach
• Oenothera issleri Renner
• Cut- evening primrose ( Oenothera laciniata Hill, Syn: Oenothera sinuata L.)
• Oenothera linifolia Nutt.
• Oenothera longiflora L.
• Missouri evening primrose ( Oenothera macrocarpa Nutt. ), Origin: USA
• Oenothera nutans G. F. Atk. & Bartlett
• Oakes ' Evening primrose ( Oenothera oakesiana ( A. Gray ) JWRobbins ex S.Watson & Coulter), Origin: North America, naturalized in Germany
• Naturalized in Europe, North America: Small-flowered Evening Primrose (Oenothera parviflora L.), home
• Oenothera perennis L., Origin: Canada and USA
• Oenothera renneri H.Scholz
• Oenothera rhombipetala Nutt. ex Torr. & A. Gray
• Oenothera rosea L' Hér. naturalized Texas and South America, Southern Europe: ex Aiton, home
• Oenothera rubricaulis adhesives.
• Oenothera rubricuspis Renner
• Oenothera silesiaca Renner
• Oenothera speciosa Nutt, home. U.S. and Mexico
• Oenothera stricta Ledebour ex Link, Origin: California, naturalized in Europe
• Oenothera strigosa ( Rydb. ) Mack. & Bush ( Syn: .. . Baurii Boedijn Oe, Oe depressa Greene, Oe hungarica Borbás )
• Oenothera stucchii Soldano
• Fragrant Evening Primrose (Oenothera suaveolens Pers. )
• Oenothera syrticola Bartlett, Origin: USA
• Oenothera tetraptera Cavanilles, Origin: Mexico
• Oenothera triloba Nutt, home. North America
• . Oenothera villosa Thunb, Origin: North America, naturalized in Germany
• Deceptive night candle or Deceptive evening primrose ( Oenothera fallax × O.Renner = Oe. Biennis × Oe. Glazioviana )
• Oehlkers ' evening primrose ( Oenothera × oehlkersii Kappus ex Rostanski = Oe. Biennis × Oe. Glazioviana )

Swell

• Jiarui Chen, Peter C. Hoch, Warren L. Wagner: Oenothera. In: Wu Zheng -yi, Peter H. Raven, Deyuan Hong (eds.): Flora of China. Volume 13: Clusiaceae through Araliaceae, Science Press / Missouri Botanical Garden Press, Beijing / St. Louis 2007, ISBN 978-1-930723-59-7, pp. 423, online. (Section Description and systematics)
• Peter C. Hoch, Peter H. Raven: Oenothera. In: Peter C. Hoch (ed.): Flora of Pakistan 139: Onagraceae. Islamabad 1981 online. ( Description section )
• Walter Erhardt et al: The big walleye. Encyclopedia of plant names. Volume 2 Eugen Ulmer Verlag, Stuttgart, 2008. ISBN 978-3-8001-5406-7