Actinidiaceae

Kiwi Blossom ( Actinidia deliciosa)

The rays stylus plants ( Actinidiaceae ) are a family of plants within the order of heather -like ( Ericales ). The best-known type is the Kiwi ( Actinidia deliciosa). They have a mainly tropical distribution, particularly from Southeast Asia down to the Malay Archipelago, but not in Africa.

  • 5.1 Notes and references

Description

Vegetative characteristics

There are woody plants: trees, shrubs or lianas. They are mostly deciduous and the above-ground parts of plants are often pubescent with simple or branched trichomes. All organs often have idioblasts with raphides, Clematoclethra with crystal sand.

The change-constant and spirally arranged leaves are divided into petiole and leaf blade. The petiole can be very short to long. The simple leaf blades are pinnately and have a smooth, usually a serrated or toothed margin. The stomata have no side cells ( Ranunculaceae type) anomocytisch. Stipules usually absent or very small.

Generative features

The flowers are individually rare, but usually zymösen in pendant, or aged men frets then inflorescences together; sometimes the " old wood ". There are mostly small bracts present.

The hermaphrodite or functionally unisexual flowers are radial symmetry, usually fünfzählig double perianth ( perianth ). If the flowers are unisexual may be getrenntgeschlechtig the species monoecious ( monoecious ) or dioecious ( dioecious ). The two to eight, usually five sepals are free, usually in the bud dachziegelig ( imbricat ) and are in a quincunx ( schraubig with a divergence of 2/ 5); they usually remain even with the fruit ripening obtained ( persistent). The three to nine, usually five petals are free or united at the base, in the bud dachziegelig ( imbricat ). They are longer than the calyx. In the bud they are imbricat. Centrifugal (10 to) formed 20 to 240 fertile stamens. The stamens can be grown freely or with the petals. The anther consists of two counters. The two-celled pollen grains have three apertures and are colporat. Three to five or many carpels are fused to a three-to upper permanent ( syncarp ), multi-chambered ovary. The surface of the ovary is hairy or smooth. In each ovary chamber are in central angle constant placentation ten to many anatrope, unitegmische, tenuinucellate ovules. Usually there is a stylus that are free or can be grown ( at Clematoclethra the pen are completely into a single fused ) receive and sometimes in the fruit ripening remain (hence the name rays pen, Actinidia from the Greek word aktis for rays) per carpel.

There are usually formed fleshy berries, sometimes more or less loculicidale, leathery capsule fruits. The relatively small seeds usually have large, straight or curved embryo and much, mostly oily, endosperm.

The basic chromosome numbers be x = 12, 13, 14; Clematoclethra with x = 12 and x = Saurauia is 13 Frequently Actinidia in a chromosome number of n = 29, which has presumably developed from tetraploid ancestor with x = 14.

Ingredients

In the family Actinidiaceae iridoids occur and widespread flavonols such as myricetin, quercetin or kaempferol. Procyanidin and prodelphinidin point to the existence of condensed tannins. Actinidin, a papain - like proteinase from the Kiwi makes contact dermatitis possible. From Actinidia polygama a terpenoid Pseudoalkaloid was isolated, which was also called actinidin. The mucus of Actinidia species contains acidic polysaccharides. Calcium oxalate crystals accumulate in raphides.

Use

Some species and their varieties, the fruit is eaten. From the few species varieties are used as ornamental plants.

Dissemination

The types of Actinidiaceae are widespread in tropical Asia and America, some even in temperate East Asia and northern Australia.

System

The Actinidiaceae family was erected in 1925 by Ernest Friedrich Gilg & Erich Werdermann in The natural plant families, Second Edition, 21, p 36. Type genus Actinidia Lindl is .. A synonym for Actinidiaceae Gilg & Werderm. is Saurauiaceae Griseb ..

The Actinidiaceae family contains only three genera comprising over 350 species:

  • Saurauia Willd. With about 300 species.
  • Rays stylus ( Actinidia Lindl. ): With about 55 to 60 species.
  • Clematoclethra ( Franch. ) Maxim. With the only kind: Clematoclethra scandens ( Franch. ) Maxim.

Swell

  • The Actinidiaceae family in APWebsite. (Section Description and systematics)
  • The Actinidiaceae family at DELTA by L. Watson & MJ Dallwitz. (Section Description and ingredients )
  • Jianqiang Li, Li Xinwei & D. Doel Soejarto: Actinidiaceae in the Flora of China, Volume 12, 2007, p 334: Online. (Section Description and systematics)
  • S. Dressler, C. Bayer: Actinidiaceae. In: K. Kubitzki (ed.): The Families and Genera of Vascular Plants. Volume 6, Springer Verlag, Cologne, 2004, pp. 14-19. ISBN 3-540-06512-1
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