Also known as Tuqi, Eggplant, Bulbous Cabbage and Rugby, also known as kohlrabi in Guangdong, it is a biennial herb in Cruciferae. According to the color of bulb skin, it can be divided into green, green and white, and purple. According to the length of the growth period, it can be divided into three types: early maturity, middle maturity and late maturity. Early-maturing varieties have short plants and small leaves, and are harvested 50-60 days after planting. Representative varieties are Beijing Zaobai and Tianjin Xiaoyingzi. Mid-and late-maturing varieties have strong growth potential and large leaves, and it takes 80- 100 days from sowing to harvesting. Representative varieties are kohlrabi, Datong pine root, Yunnan constant wave blue and so on.