[Grey relational analysis on early bolting of Angelica and its main factors]

Selecting the principal environmental and cultivated factors from the main production areas of Angelica sinensis in Gansu, the problem of early bolting were analysed with grey system theory. After the quantitative analysis, the relational grade was: elevation > precipitaton > density of crop > organic fertilizer > phosphorus fertilizer > nitrogen fertilizer. The research would provide scientific basis for check on the rate of the early bolting of Angelica effectively as well as improve the product and benefits.