D³ database

Diaspore Typology

Summary

 

DIASPORE TYPOLOGY is a categorical trait which describes the morphological structure that acts as the diaspore, i.e. the dispersal unit (e.g. a seed or a fruit). Generally, we only regard long-distance dispersal strategies.

 

Trait description

 

DIASPORE TYPOLOGY (column code: DIA_TYPE) is coded as one of the categories listed in Tab. 1.

 

Some species may produce more than one diaspore type. For instance, in Festuca ovina agg. the fruit of one flower (including the surrounding glumes) as well as all fruits of one spikelet (including the surrounding glumes) may act as diaspores. Such species are marked as 'heterodiaspore' (see Heterodiaspory), and additional diaspore types are characterized in the 'comment' field.

 

Furthermore, some species are not able to produce any diaspores (e.g. sterile hybrids) or reproduce by vegetative parts without long-distance dispersal potential (e.g. clonal growth by rhizomes). Generally, we disregard these organs because they do not influence long-distance dispersal and only list them if no other diaspore type is known (more details see No. 7 in Tab. 1). In contrast, vegetative parts which allow long-distance dispersal, like turions or bulbils that easily detach from the mother plant, are marked as 'specialized vegetative part' (more details see No. 6 in Tab. 1).

 

 

Tab. 1. Categorization of diaspore types

No.

Category

Description and examples

 

1

seed

('seed' in Morphology Code)

The seed acts as the diaspore.

The diaspore may also include additional structures (e.g. elaiosomes) but never comprises a complete fruit.

 

E.g. many Gymnospermes, Brassicaceae, Campanulaceae, Caryophyllaceae, Papaveraceae

Papaver rhoeas - The seed acts as the diaspore and is released from a capsule.

2

fruit segment

('segm' in Morphology Code)

Fruit segments act as the diaspores. Fruit segments develop from a fruit that splits into several parts during maturity (e.g. Acer) or from a fruit that is composed ab initio of several fruitlets (e.g. Ranunculus).

The diaspore may also include additional structures but never comprises a complete fruit. 

 

E.g. many Aceraceae, Apiaceae, Boraginaceae, Lamiaceae

Acer tataricum - During maturity the fruit is splitting into two fruit segments (diaspores) which are dispersed independently.

 


Ranunculus acris - The fruit consists of many not connate nutlets (diaspores) which are dispersed independently.

3

fruit

('fruit' in Morphology Code)

The fruit acts as the diaspore.

The diaspore may also include additional structures but NEVER comprises fruits from MORE THAN ONE flower.

 

E.g. many Asteraceae, Poaceae, Fragaria, Malus, Rubus

Taraxacum Sect. Ruderalia - The fruit (including the pappus) acts as the diaspore.

4

infructescence

('infr' in Morphology Code)

The infructescence or a part of the infructescence with fruits from MORE THAN ONE flower acts as the diaspore. Also included are compound fruits which are composed of tightly adnate fruits

E.g. Ananas comosa, Tilia, Morus

Tilia platyphyllos - The diaspore is built from a few fruits of an infructescence and its adnate bract.

5

whole plant

('plant' in Morphology Code)

More or less the whole plant, mostly the above-ground part including MORE THAN ONE infructescence, acts as the diaspore.

E.g. tumbleweeds like Salsola tragus

Salsola tragus - The aboveground part is drifted by the wind and acts as the diaspore. Picture taken by Edmond Meinfelder.

6

specialized vegetative part

('vege' in Morphology Code)

Specialized vegetative structures, e.g. bulbils, offshoots or turions, act as diaspores AND allow - in principle - long-distance dispersal as they detach easily from the mother plant.

This category is NOT applied to seeds that develop without sexual recombination (e.g. by apomixes) or clonal growth organs (e.g. rhizoms, stolons, bulbs) that do not allow long-distance dispersal.

E.g. Dentaria bulbifera, Poa bulbosa, Trapa natans

Poa bulbosa - The spikelets are transformed into vegetatively produced bulbils, which rapidly start their development (pseudovivipary).

7

no diaspore

('no' in Morphology Code)

Reserved for sterile hybrids or taxa with ONLY short-distance dispersal with vegetative parts (clonal growth, fragmentation of vegetative parts etc.).

E.g. Betula x aurata (sterile)

 

8

cone

('cone' in Morphology Code)

Reserved for gymnosperms if the whole cone functions as a diaspore.

 

E.g. Juniperus, Ephedra 

Juniperus communis - branch with several fleshy cones.

9

spore

('spore' in Morphology Code)

Reserved for non-spermatophytes, which are not included in D³ yet.

 

E.g. mosses and ferns

Dryopteris  sp. - spore (left) and leaves with sori, i.e. groups of sporangia with spores on their underneath.

10

other

('other' in Morphology Code)

Diaspore types that are not covered by one of the above mentioned categories.

Data sources

 

DIASPORE TYPOLOGY was categorized by visual inspection of diaspores and fruits or respective images in addition to an intensive literature and web research.

 

 

Selected literature

 

Bojňanský, V. & Fargašová, A. (2007): Atlas of seeds and fruits of Central and East-European flora. The Carpathian Mountains region. Springer, Dordrecht.

 

Brouwer, W. & Stählin, A. (1975): Handbuch der Samenkunde für Landwirtschaft, Gartenbau und Forstwirtschaft. DLG-Verlag, Frankfurt.

 

Cappers, R.T.J., Bekker, R.M. & Jans, J.E.A. (2006): Digital Seed Atlas of the Netherlands. Barkhuis. Eelde (NL).

 

Graf, J. et al. (1987): Tafelwerk zur Pflanzensystematik. Einführung in das natürliche System der Blütenpflanzen. Springer-Verlag.

 

Hegi, G. (1908ff): Illustrierte Flora von Mittel-Europa. Mit besonderer Berücksichtigung von Deutschland, Oesterreich und der Schweiz. Zahlreiche Bände in drei Auflagen. J. F. Lehmanns Verlag, 2. und 3. Auflage bei Paul Parey und Weissdorn-Verlag.


Hilger, H.H. & Hoppe, J.R. (1995): Die morphologische Vielfalt der generativen Diasporen – Präsentation eines Lehr- und Lernschemas. Feddes Repertorium 106, 503-513.

 

Müller-Schneider, P. (1977): Verbreitungsbiologie (Diasporologie) der Blütenpflanzen. Veröffentlichungen des Geobotanischen Institutes der ETH, Stiftung Rübel 61.

 

Müller-Schneider, P. (1986): Verbreitungsbiologie der Blütenpflanzen Graubündens. Veröffentlichungen des Geobotanischen Institutes der ETH, Stiftung Rübel, 85.

 

Otto, B. (2002): Merkmale von Samen, Früchten, generativen Germinulen und generativen Diasporen. In: Klotz, S., Kühn, I. & Durka, W. [Hrsg.] (2002): BIOLFLOR - Eine Datenbank zu biologisch-ökologischen Merkmalen der Gefäßpflanzen in Deutschland. Schriftenreihe für Vegetationskunde 38, Bonn: Bundesamt für Naturschutz, 177-196.

 

Poschlod, P., Tackenberg, O. & Bonn, S. (2005): Plant dispersal potential and its relation to species frequency and coexistence. In: Van der Maarel, E. (Editor). Vegetation Ecology, chapter 6. Wiley-Blackwell.