Introduction
Mustard family
A cosmopolitan, mainly herbaceous family, recognised by cruciform flowers and the mustard taste of the leaves. Renowned for the numerous vegetables that belong to this family.
Distribution
Occurring worldwide, mostly in the northern hemisphere in countries surrounding the Mediterranean and in southwestern Asia, rarely found in the tropics. In southern Africa there is a concentration of species in the winter-rainfall area of the Western Cape.
Number of genera in the world
ca. 340
Number of species in the world
ca. 3 350
Number of genera in the Flora of southern Africa region
29
Number of species in the Flora of southern Africa region
174
Well-known southern African genera
Heliophila, Lepidium, *Raphanus
Growth forms
Annual or perennial herbs, shrublets or seldom small trees or climbers.
Habitats
Found in almost every kind of habitat from alpine areas to desert, forest and aquatic areas.
Flagship species
Heliophila juncea (=Brachycarpaea juncea< /EM>; wild stock; kraaibos [A]) is a willowy shrublet of up to 1 m high and is covered in white, mauve or purple flowers during spring and summer. Flowering is best after fire. The fruits are disc-shaped and woody when dry. This species is usually found in fynbos vegetation from the mountainous areas around Springbok in the north to the Eastern Cape.
Significance of the family
This family contains numerous and diverse crop plants, including food plants such as broccoli, cabbage and turnip; condiments and garnishes like mustard, cress and horseradish. Vegetables collected from the veld include Lepidium species and Sisymbrium capense. Certain Lepidium species are known to be used medicinally. Both edible and industrial oils are extracted from the seeds of some members of the family (*Brassica, *Raphanus, *Sinapsis). Some species are cultivated as garden ornamentals (*Alyssum, Heliophila, *Nasturtium).
Diagnostic characters
Leaves alternate , often in basal rosettes, without stipules and often with a mustard taste. Inflorescence usually a slender raceme without bracts or bracteoles. Flowers regular with 4 sepals and 4 free petals, arranged in the form of a cross (cruciform) . Stamens 6 , usually 4 long and 2 short. Ovary superior �. Fruit a dry, 2-chambered capsule (siliqua or silicula), usually opening by two valves from below .
Did you know?
Canola oil is produced in the Overberg region in the Western Cape. The oil is pressed from the tiny seeds of the canola plant (*Brassica napus).