Rapistrum

Life-forms

Classification System: APG IV

Superregnum: Eukaryota
Cladus: Orthokaryota
Cladus: Neokaryota
Cladus: Photokaryota
Cladus: Diaphoretickes
Cladus: CAM
Regnum*: Archaeplastida
Regnum: Plantae
Regnum*: Viridiplantae
Cladus: Streptophyta
Cladus: Phragmoplastophyta
Cladus: Embryophyta
Cladus: Polysporangiophyta
Divisio*: Tracheophyta
Cladus: Eutracheophyta
Cladus: Euphyllophytina
Cladus: Megaphylla
Cladus: Radiatopses
Cladus: Lignophyta
Cladus: Metalignophyta
Diviso*: Spermatophyta
Classis*: Angiospermae
Cladus: Mesangiospermae
Cladus: Eudicota
Cladus: Core eudicots
Cladus: Rosids
Cladus: Eurosids II
Ordo: Brassicales

Familia: Brassicaceae
Subfamilia: Brassicoideae
Tribus: Brassiceae
Genus: Rapistrum
Species: R. perenne – R. rugosum
Name

Rapistrum Crantz, 1769

Type species: Rapistrum hispanicum (L.) Crantz

Synonyms

Schrankia Medik.
Stylocarpum Noulet

References

Crantz, H.J.N.v. 1769. Classis Cruciformium Emendata 105–107.

Links

Koch, M.A. et al. 2019. Rapistrum in BrassiBase Tools and biological resources to study characters and traits in the Brassicaceae. Published online. Accessed: 2019 May 25.
International Plant Names Index. 2019. Rapistrum. Published online. Accessed: May 25 2019. Reference page.
The Plant List 2013. Rapistrum in The Plant List Version 1.1. Published online. Accessed: 2019 May 25.
Tropicos.org 2019. Rapistrum. Missouri Botanical Garden. Published online. Accessed: 25 May 2019.

Vernacular names
suomi: Saksanretikat

Rapistrum, the bastard cabbages,[1][better source needed] is a genus of the family Brassicaceae with a distinctive cross like arrangement of its petals. It is also known[2] as wild-turnip or turnipweed. Species of Rapistrum are annual to perennials (Lifespan from 1 to 2 or more years). The yellow petals are accompanied by sepals that stand vertically at near right angles (erecto-patent). Leaf shape and arrangement varies from rough toothed (dentate) to a configuration of opposingly lobed pairs along the plant stalk, pinnately lobed.
Etymology

The word "Rapistrum" is formed from the Latin rapa ("turnip") and -astrum, ("incomplete resemblance").[3]
Fruit

The genus Rapistrum has a characteristic fruit comprising two segments, one distal and one proximal:

The distal (upper division) is the part of the fruit farthest away from the point of attachment. The distal is endowed with a ribbed spheroid base (globose) that tapers to form a narrowed projection. It holds a single seed.

The proximal (lower division) is the part of the fruit nearest to the point of attachment. Possesses a more uniform narrower shape compared to the distal above, giving the fruit a waist. It holds a maximum of three seeds, more commonly none or one.

The fruit varies between species in the genus. The distal of R. rugosum is strongly ribbed and narrows to form a beak whereas R. perenne is comparatively less wrinkled and ends with a style that stubbornly resists detachment, 'a persistent style'.

When ripe the distal breaks away in an across-wise fashion, breaking transversely.
References

NRCS. "Rapistrum". PLANTS Database. United States Department of Agriculture (USDA). Retrieved 18 October 2015.
"Rapistrum". Flora North America. Retrieved 2024-09-12.

Warwick, Suzanne I. "Rapistrum". Flora North America.

Bibliography

Stace, C. (1999), Field flora of the British Isles, Cambridge: Cambridge University Press, ISBN 0-521-65315-0.
Streeter, D. (1983), The wild flowers of the British Isles, London: Midsummer Books Ltd., ISBN 1-900732-03-3.