Brassicaceae

Plant Sex: Flowers bisexual.

Flowers: Actinomorphic, 4-merous. Alternate family name Cruciferae derives from "cross" with reference to the 4 petals. Stamens 4 long and 2 short = TETRADYNAMOUS. Gynoecium, hypogynous, bicarpellate, syncarpous.

Inflorescence: Racemes, sometimes solitary on a scape.

Fruits: SILIQUES - more than 3X long as broad; SILICLES - less than 3X long as broad. False septum called a REPLUM. Taxonomically important character deals with whether the fruit is flattened parallel or at right angles to replum. This applies to both siliques and silicles.

Habit: Annual, biennial, perennial herbs with mustard oils.

Leaves: Alternate, simple, or often pinnately compound or lobed (pinnatifid).

Examples:

Food Plants
Brassica

B. oleracea - broccoli, cabbage (edible), cabbage (ornamental), cauliflower, brussel sprouts, kale, etc.
B. napus. Field of mustard in Belgium. Other mustard species: B. juncea, B. alba, B. nigra.
B. rapa. Field of mustard. Flower. Flower L.S.

Raphanus

R. sativus (radish). Cultivated for their edible taproots. Flowers.

Wildflowers
Dentaria

D. laciniata (toothwort). Habit of one of our common spring wildflowers. Flowers. Flower L.S.

Cardamine

C. hirsuta (spring cress). The silique explosively dehisces the seeds upon the slightest touch!

Ornamentals
Hesperis

H. matronalis (dame's rocket). Plant in the field. Inflorescence. Flower L.S. Fruit developmental series.

Iberis

Iberis sp. (candy tuft). Habit of cultivated plant in flower. Note the flowers are bilaterally symmetrical.

Lunaria

L. annua (money plant). Lunaria is cultivated because the dry replum from its silicle resembles a coin (hence the common name).

Weeds
Capsella

C. bursa-pastoris (shepherd's purse). Habit. Inflorescence.

Alliaria

A. petiolata (garlic mustard). A population along SIUC campus lake. Closer view of the plant.

Model Organisms
Arabidopsis

A. thaliana (mouse-ear cress). The most important model angiosperm for genetics and development.

Thlaspi

T. arvense. Plant with flowers and fruits. Another important plant for studying heavy metal accumulation and tolerance (see Ebbs website).

SIUC / College of Science / Elements of Plant Systematics
URL: http://www.plantbiology.siu.edu/PLB304/Lecture19Fagal/Brassicaceae.html
Last updated: 01-Apr-09 / dln