Stamp (botany)

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Sketch of a pistil with pollen (p) on the stigmas (n) and pollen tubes (ps) with stylus (g) and (fs) stem-like base of the ovary Multiple pen stamps by Linum
Sketch of a pistil with pollen (p) on the stigmas (n) and pollen tubes (ps) with stylus (g) and (fs) stem-like base of the ovary
Multiple pen stamps by Linum

As a stamp or pestle is referred to in the Botany a unit of a gynoecium which both single, free, as well as together to form a coenokarpen an ovary fused carpels the flowering of some Bedecktsamer includes.

However, some authors only refer to fused or coenocarpic carpels as pistils. The name was given because of the similarity with the pestle as a tool with which grated material is crushed in a thick-walled mortar .

The punch is divided into a lower fertile portion of the most bulging ovary (ovary) with the ovules , and often a sterile section often narrow and long with the pen , which at its upper end scars carries. As with the tulip , these can also sit directly on the ovary without the stylus. The scars pick up pollen grains during pollination , the stylus guides the germinating pollen tubes to the ovary. This is where the ovules are fertilized .

In the case of a coenocarpic ovary, one pistil can also have several styluses and scars. A stylus can now have several stylus branches each with a scar (synstylovarious) or free styluses each with a scar (synovarious). If several, individual and apocarpic pistils are present and the scars and partly also the stylus are fused, a gynostegium is created (the entire structure is also referred to as a stamp). It is also possible that the adjacent carpels are only partially, just overgrown with free styles (hemi-apocarpous, semicarpous) or are connected by the flower base (pseudo-coenocarp).

A stamp can also be stalked with a stamp foot or podogynium, gynopodium, z. B. as with the Hunds-Rose . Here a narrowed basal part of the ovary forms a smaller stalk or podium. Other stem-like extensions such as the gynophore and androgynophore are to be distinguished . a., which are formed from the flower axis , or the carpophor , the fruit holder . If the foot or the handle is disc-shaped, this is called a gyno base (stamp pad, floor), this can correspond to a nectar-exuding disc .

There can rarely be two or more pistils of different flowers wholly or partially fused to form a syngynium (pseudo-monomeric) → see also ovary . A stamp can also be sterile and is then referred to as a “pistillode”, it is then often stunted.

See also


Web links

Commons : Stamp  - collection of images, videos and audio files

Individual evidence

  1. ^ Murray W. Nabors : Botany. Pearson, 2007, ISBN 978-3-8273-7231-4 , p. 6.
  2. G. Singh: Plant Systematics. Science Publishers, 2004, ISBN 1-57808-342-7 , p. 79.
  3. Emmanuel Le Maout , Joseph Decaisne : A General System of Botany Descriptive and Analytical. Longmans, Green, 1876, p. 70.
  4. ^ Gottlieb Wilhelm Bischoff : Textbook of Botany. Swiss Beard, 1839, p. 92.