''Rapistrum'', the bastard cabbages, is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of the family

Brassicaceae Brassicaceae () or (the older but equally valid) Cruciferae () is a medium-sized and economically important Family (biology), family of flowering plants commonly known as the mustards, the crucifers, or the cabbage family. Most are herbaceous pla ...

with a distinctive cross like arrangement of its

petal Petals are modified leaves that form an inner whorl surrounding the reproductive parts of flowers. They are often brightly coloured or unusually shaped to attract pollinators. All of the petals of a flower are collectively known as the ''corol ...

s. It is also known as wild-turnip or turnipweed. Species of ''Rapistrum'' are

annual Annual may refer to: *Annual publication, periodical publications appearing regularly once per year **Yearbook **Literary annual *Annual plant *Annual report *Annual giving *Annual, Morocco, a settlement in northeastern Morocco *Annuals (band), a ...

perennials In horticulture, the term perennial ('' per-'' + '' -ennial'', "through the year") is used to differentiate a plant from shorter-lived annuals and biennials. It has thus been defined as a plant that lives more than 2 years. The term is also ...

(Lifespan from 1 to 2 or more years). The yellow petals are accompanied by

sepal A sepal () is a part of the flower of angiosperms (flowering plants). Usually green, sepals typically function as protection for the flower in bud, and often as support for the petals when in bloom., p. 106 Etymology The term ''sepalum'' ...

s that stand vertically at near right angles (erecto-patent).

Leaf shape The following terms are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (that is, the leaf blade or 'lamina' is undivided) or compound (that is, the leaf blade is divided into two or more leaflets ...

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").

Fruit

The genus ''Rapistrum'' has a characteristic

fruit In botany, a fruit is the seed-bearing structure in flowering plants (angiosperms) that is formed from the ovary after flowering. Fruits are the means by which angiosperms disseminate their seeds. Edible fruits in particular have long propaga ...

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

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 Style, or styles may refer to: Film and television * ''Style'' (2001 film), a Hindi film starring Sharman Joshi, Riya Sen, Sahil Khan and Shilpi Mudgal * ''Style'' (2002 film), a Tamil drama film * ''Style'' (2004 film), a Burmese film * '' ...

that stubbornly resists detachment, 'a persistent style'. When ripe the distal breaks away in an across-wise fashion, breaking transversely.

References

Bibliography

*. *. {{Taxonbar, from=Q162891 Brassicaceae Brassicaceae genera