Species Origin and Economic Importance of Brassica

Abstract

The genus Brassica is one of 51 genera in the tribe Brassiceae belonging to the crucifer family, and is the economically most important genus within this tribe, containing 37 different species (Gomez-Campo 1980). Many crop species are included in the Brassica genus, which provide edible roots, leaves, stems, buds, flowers and seed. Next in agronomic importance are the genera Raphanus, cultivated for its edible roots and Sinapis as a source of condiments. There are many wild relatives that have potential as sources for oil, condiments and other products. Wild relatives could serve as sources for cytoplasmic male sterility (androsterility) for the development of hybrid seed production systems in Brassica crop plants and provide nuclear genes for resistance to different diseases and pests. Certain visible characters are informative in the Brassiceae. Mucilage is a very common phenomenon in seed of plants of the tribe Brassiceae, and is therefore of taxonomic value. For instance, seeds of the 9 chromosome species of the genus Sinapis such as S. arvensis contain no mucilage, while the 12 chromosome species such as S. alba contain mucilage. Some species of Sinapis and Crambe have hairy cotyledons, which is an exception. Drought-adapted genera such as Moricandia tend to be glabrous, but they are more sensitive to aphids than hairy species. There is a wide variation in flower shape and colour from yellow to white to violet (Moricandia), and the colour of mature seeds varies from yellow to black.