1. Brassica rapa var.chinensis (Linnaeus) Kitamura is a cruciferous annual or biennial herb of Brassica, with a height of up to 70cm, no hair, thick roots, hard, inverted or wide inverted basal leaves, solid, dark green, shiny, and petiole with or without narrow edges; Racemes terminal, paniculate; The flower is light yellow, the pedicel is thin, equal to or shorter than the flower; Sepals oblong, white or yellow; Petals oblong, round and blunt at the top, veined, longhorn linear, with obvious midvein and reticulate lateral vein; The tip of the beak is thin, and the seeds are spherical, purple brown, with honeycombed lines.
 2. It blooms in April and bears fruit in May.
 3. It is native to Asia.
 4. It is cultivated in the north and south provinces of China, especially in the Yangtze River basin.
 5. Green vegetables are one of the most common vegetables in China.