Diaspore
Diaspore or Propagule is the collective botanical term for all units that promote dissemination, such as seeds , partial fruits , fruits , infructescence , spores , brood buds (bulbils) or other vegetative brood bodies that are used for the spread of plants or fungi .
The term “seeds” used in common parlance is botanical, for morphological reasons it is not always applicable. The actual seed of the umbelliferae, for example, remains enclosed by the pericarp until germination; the connection between the seed and pericarp is so tight that the seed cannot be freed from it without injury. Diaspores can also include other plant parts, for example in the case of the linden tree , where the cover leaf has grown together with the stalk of the fruit cluster and serves as a wing for the wind to spread .
We differentiate between vegetative and generative diaspores. Vegetative diaspores, e.g. B. cuttings or bulbs, tubers or rhizomes, are produced in an asexual way, so do not differ genetically from the mother plant. Generative diaspores are seeds, spores and fruits, infructescence.
The totality of all germinable plant dispersal units (diaspores) present at a location is referred to as the diaspore bank.
Distinction
- Telechore ; increased effect of the spread
- Antitelechor, topochor ; inhibiting effect of spread
- Atelechor; no effect to increase the spread
- Barospermia; the spread of the seeds is limited by the weight of the diaspores.
- Opening only when wet; Hygrochasia
- Opening only when it is dry; Xerochasia
- secrete mucus; myxochor
- are winged; pterophore
- with hooks and spikes; acanthopor
- spherical, light; sphaeromorph , cyclochor
- with hair umbrella ( pappus , awn ); pogonophore
- with hygroscopic appendix; trypanophore , loconophore
- with elaiosome ; elaiosomophore
- aerated; saccophore
- fleshy; sarcophor
According to the mode of expansion:
In matrispermia there are expanded structures of the diaspores to the mother plant.
- Matrichorie; the structure of the mother plant facilitates long-distance spreading
- Matristasy; the structure of the mother plant hinders long-distance spread
In synaptospermia , several diaspores are grouped together.
- Eusynaptospermia ; two or more subunits that are later isolated
- Pseudosynaptospermia ; Subunits already isolated during expansion
It can be further divided into:
- Synaptochory; Diaspores with structures for long-distance spreading
- Synaptostasis; Diaspores without structures for long-distance spread
In heterodiasporia , one species produces several types of diaspore ( heteromorphism ). One can further subdivide into:
- Heterocarpy (disparity); the occurrence of differently shaped fruits
- Heteroarthrocarpy , heteromericarpy ; the formation of different partial fruits
- Heterospermia ; the formation of differently shaped seeds on a plant
- Amphibasic carpie ; Flowers and differently shaped fruits on the same individual near the ground
-
Amphicarpy (double fruitiness ); differently shaped fruits on the same individual due to fruits that are formed or ripen at the same time in the air (aerocarp) and in the ground (geocarp)
- Amphigeocarpy ; Flowers above and below ground, as well as differently shaped fruits on the same individual due to fruits that are formed or ripen at the same time in the air and in the ground.
- Flowers on top of deer or near the ground, as well as differently shaped fruits on the same individual due to fruits that are formed or ripen at the same time in the air and in the ground.
Tachysporia is the name for the rapid release and bradychory , bradysporia (phytophoria) for the slow, delayed release of diaspores. There are two types of bradysporia, first of all winter men (hiemophores) and summer men (estatiophores). Macrobiocarpy is also possible , in which the fruits remain on the mother plant for an unlimited number of years, even after the seeds enclosed in them have reached full maturity.
There is also seminal retention (serotinia); the seeds are only released after exposure to certain conditions. The following conditions can be considered:
- Death of the mother plant or branch (necriscenie, death can be caused by fire)
- Wetting (hygriscenia) (hygrochasy)
- Solar heating (Soliscenie)
- Desiccant atmospheric conditions (xeriscenie) (xerochasy)
- Fire (heat, essentially: pyriscenia) (pyrophytes)
- Fire followed by wetting (pyrohydriscenie)
literature
- Ursula Hoffmann, Michael Schwerdtfeger: And the golden tree of life - pleasure trips and educational trips in the realm of plants . Ulrich Burgdorf Verlag, Göttingen 1998, ISBN 3-89762-000-6 .
- Angelika Lüttig, Juliane Kasten: Rosehip & Co. - Flowers, fruits and spread of European plants . Fauna Verlag, Nottuln 2003, ISBN 3-935980-90-6 .
- Wolfgang Frey , Rainer Lösch : Geobotany. 3rd edition, Springer 2010, 2014, ISBN 978-3-662-45280-6 , pp. 328-352.
- B. Schmid, J. Stöcklin: Population biology of plants. Springer, 1991, ISBN 978-3-0348-5638-6 , p. 42 ff.
- Ahmad Hegazy, Jonathan Lovett-Doust: Plant Ecology in the Middle East. Oxford University Press, 2016, ISBN 978-0-19-107874-3 .
Individual evidence
- ↑ Theodor CH Cole: Dictionary of Biology. 4th edition, Springer, 2015, ISBN 978-3-642-55327-1 , p. 22.
- ↑ Marie Lhotská: contribution to the Termiologie Diasporologie. In: Folia Geobotanica et Phytotaxonomica. Volume 10, Issue 1, 1975, pp. 105-108, doi : 10.1007 / BF02855106 .
- ↑ a b Carol C. Baskin, Jerry M. Baskin: Seeds. Second Edition, Academic Press, 2014, ISBN 978-0-12-416677-6 , pp. 192, 341.
- ↑ K. van Rheede van Oudtshoorn, Margaretha W. van Rooyen: Dispersal Biology of Desert Plants. Springer, 1999, ISBN 3-540-64886-0 , p. 143.
- ↑ Wolfgang Frey, Rainer Lösch: Geobotany. 3rd edition, Springer, 2010, 2014, ISBN 978-3-662-45280-6 , p. 351.