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Publisher Summary Chinese cabbage (Brassica pekinensis and B. chinensis, 2n = 20) is annually grown as a salad crop. It is indigenous to China and eastern Asia, where it has been in cultivation since the fifth century. Two more or less distinct species of Chinese cabbage are grown. One of these species is Pe-tsai—Brassica campestris subsp. pekinensis (B. pekinensis). This resembles Cos lettuce but produces a much larger head that is elongated and compact. The other species is Pak-choi—Brassica campestris subsp. chinensis (B. chinensis). This resembles Swiss chard in growth habit. The leaves are long, dark-green, and oblong or oval, and they do not form a solid head. It is also called Chinese mustard. This chapter provides an overview of cytology and genetics of Chinese cabbage. Chinese cabbage contains 2n = 20 chromosomes. Brassica pekinensis contains two nucleolus-organizing chromosomes per haploid set. The chapter describes the interspecific hybridization of Chinese cabbage. Population improvement is the main procedure in improving Chinese cabbage. This includes mainly recurrent selection, mass selection, and population breeding involving development of synthetics and composites. Chinese cabbage varieties have been classified into three groups by growing season in Louisiana: (1) spring varieties (January to April), (2) tropical varieties (April to July), and (3) autumn or main season variety (August to September). |
