ABSTRACT
The genus Brassica in the family Brassicaceae includes about 40 species, some of which are commercially important as oil seeds, leaf and stem vegetables, condiments, forage, and fodder and green manure. Brassica is a temperate genus with origins probably in the Mediterranean and Near East and in China and India. The vernalization and photoperiodic requirements of Brassica are important in matching a cv with its climate in order to optimize yield. The bisexual flowers are typical of the Brassicaceae, with 4 sepals and 4 clawed petals spread in the form of a cross, an outer whorl of 2 short stamens and an inner whorl of 4 long stamens, a superior ovary with 2 carpels and 2 stigmas on a short style. A period of exposure to low temperature may be essential for flowering in some varieties of Brassica. Devernalization also occurs when a few days at low temperature are alternated with high temperatures.
