Chrysanthemum
Chrysanthemum japonense
The chrysanthemums (Chrysanthemum ) are a genus of flowering plants from the sunflower family ( Asteraceae) with about 40, mainly distributed in East Asia species. They are among the most important ornamental plants.
Description
Chrysanthemums are perennial, usually herbaceous plants, but occasionally at the base woody dwarf shrubs. The leaves are alternate, weak to strong, pinnate, lobed or sometimes entire.
The three-row involucre is more or less saucer -shaped, the Involucralblätter imbricate superimposed are wide margins membranous or dark brown. The basket bottom is convex to slightly conical, chaff leaves are missing. The single row ray florets are female, fertile and have a white, pinkish or yellowish tongue. The hermaphroditic disc florets are yellow, the tube- to five-lobed corolla tube cone-shaped, glandular hairy and wingless. The tabs at the base of the anther missing, those are approximately triangular at the outer end. A pappus is lacking.
Dissemination
The genus is mainly distributed in East Asia (China, Korea, Japan ), but emits about Russia all the way to Eastern Europe (Chrysanthemum zawadskii ).
Systematics and botanical history
The genus name comes from the already used the Elder Pliny name chrisánthemo, χρυσάνθεμο, chrysanthemum = the gold flower, gold flower from: ancient Greek χρυσός Chrysos "Gold" and ancient Greek ἄνθος anthos " flower ", " flower "
At times, most of the genus was addressed as Dendranthema, only a decision of the ICBN preserved the name Chrysanthemum.
The genus is very close to some genera, especially the Ajania. Natural as artificial hybrids of species and genus borders on ( as with Ajania, Crossostephium chinense, Nipponanthemum nipponicum, Leucanthemella linearis, Tanacetum vulgare Tanacetum parthenium or ) presented the delimitation of the genus and its related genera repeatedly questioned. As early as 2004 it was proposed to unite the genus Chrysanthemum with the genera Ajania, Arctanthemum and Phaeostigma. Molecular genetic studies supported this ( with the exception of Phaeostigma ), recent investigations on the chrysanthemums form a clade together with the Ajania, Ophistopappus and Elachanthemum.
The genus is divided into two sections ( Sect. Chrysanthemum and Sect. Chlorochlamys ). The genus includes about 40 species, including:
- Florist's Chrysanthemum (Chrysanthemum morifolium × )
- Chrysanthemum argyrophyllum
- Chrysanthemum boreale
- Chrysanthemum chanetii
- Chrysanthemum coreanum
- Chrysanthemum dichrum
- Chrysanthemum foliaceum
- Chrysanthemum glabriusculum
- Chrysanthemum hypargyrum
- Chrysanthemum indicum
- Chrysanthemum japonense
- Chrysanthemum japonicum
- Chrysanthemum lavandulifolium
- Chrysanthemum maximowiczii
- Chrysanthemum mongolicum
- Chrysanthemum oreastrum
- Chrysanthemum naktongense
- Chrysanthemum nankingense
- Chrysanthemum ornatum
- Chrysanthemum potentilloides
- Chrysanthemum rhombifolium
- Chrysantemum sinense
- Chrysanthemum vestitum
- Chrysanthemum yezoense
- Chrysanthemum yoshinaganthum
- Chrysanthemum zawadskii
Use
Appreciated is especially the garden chrysanthemum, which is cultivated in China since 1600 years. Already in the eleventh century there were 36 varieties.
End of the 17th century Chrysanthemums were first introduced to Europe in 1862 sent Robert Fortune breeding plants from Japan to Europe, which became the basis of European breeding chrysanthemums. Today Chrysanthemums are globally widespread and popular ornamental plants, the garden chrysanthemum is even regarded as "one of the most important horticultural crops ". The number of varieties is now estimated at a few thousand pieces.
Some Tanacetum species such as the Dalmatian insect flower, which are used for the production of pyrethrum as an insecticide, were formerly assigned to the chrysanthemum.