Brassica juncea, alias: Brassica juncea, Brassica campestris, Brassica juncea; Brassica napus originated in China and is cultivated all over the country. It is also cultivated all over Asia. Rape is one of the main oil crops in China. It has wide adaptability, large reproductive coefficient, suitable for stubble arrangement under various farming systems, and has certain functions of activating and enriching soil nutrients, so many provinces and regions also cultivate and utilize it as a green manure crop. It is not one species, but contains several species of Brassicaceae. It is usually divided into three types: Chinese cabbage rape, mustard rape and cabbage rape. All three types of rape varieties can be cultivated as green manure. Commonly used as green manure, mainly several varieties of the first two categories. Mustard is one of two kinds of mustard, and the other is mustard.