Edited by Ho Dinh Hai Long An - Vietnam Updated: 14/08/2015
1- Introduction to the Family Cannaceae
1.1- Overview Cannaceae, the canna family of the ginger order (Zingiberales), a single genus with about 19 species, distributed from southeastern North America through South America. The familyCannaceaeis in the major groupAngiosperms(Flowering plants). These tropical herbs possess rhizomes (underground stems) with erect stems growing to 3 m (10 feet) high. The tall or dwarf foliage displays spirally arranged leaves that may be green or bronze. The flowers are asymmetrical, with one half-functional stamen and a labellum, a petal-like structure rolled outward. The two to three “petals” are actually sterile stamens (staminodes); there are also three regular petals. Sometimes spotted variations of the scarlet, red-orange, or yellow flowers occur. The genus Canna is widely grown for ornamental use. One species, C. edulis,from Peru has edible, starchy rhizomes.
2.1- Description Cannaceae is one of the plants with a long history of human cultivation. Records that go back to 2500 B.C in Peru show that the people then were using the rhizomes of Canna indica(Gade, D.W. 1966).Cannawas also described in the writings of many botanists that came before of Linnaeus. It was in the list of many gardens under different names. Cannaceae is one of the easy to recognise and distinctive families due to the clear characters it has. They are perennial plants with rhizomes. + Plant Plant is Herb and Perennial; without conspicuous aggregations of leaves; 0.5-5 m high; rhizomatous, helophytic, or mesophytic. Young stems cylindrical (terete). Secretory cavities present; with mucilage. Secondary thickening absent. The axial xylem without vessels. Plants with silica bodies (these internal, in association with the vascular bundles). Root xylem with vessels and without vessels (mainly simple). + Leaves Leaves are arranged spirally with a sheathing base and no ligule. Leaves medium-sized to large; alternate; spiral; flat, or rolled; more or less petiolate; sheathing. Leaf sheaths with free margins. Leaves simple; epulvinate. Lamina entire; linear, or lanceolate, or oblanceolate; pinnately veined (with parallel-convergent laterals); without cross-venules; attenuate at the base. Lamina margins entire; flat. Vernation convolute. + Flowers The inflorescence is terminal. Flowers are big and showy with range of colours red, pink, yellow or orange. The flower has 3 sepals and is variously interpreted as having staminodes functioning as petals or petals and staminodes, one is smaller than the other two. The ovary is inferior with 3 carpels. + Fruits The fruit is hard and has a warty surface divided to 3 parts. Fruitnon-fleshy; dehiscent; a capsule (usually warty). Capsules opening by collapse of the pericarp. + Seeds The seeds are black and hard. Seeds thinly endospermic (the endosperm consisting of a thin, starchy layer).