The geographical distribution of soil elements determines the boundaries of the Daodi-zone of medicinal plant (Ligusticum chuanxiong Hort.)

Abstract. Understanding the boundary of plants' best production zone is of great significance to the rational introduction cultivation. We set up 9 sample points in the center-zone and 28 sample points extending eastward along the longitude. Then, we were collecting the bulk soil of L.chuanxiong, testing soil properties and elements. Later, a multi-point cultivation test was carried out on L.chuanxiong, the content of elements in the plant measured by ICP-MS, and HPLC detected the active ingredients. Based on hierarchical clustering and PCA analysis, the study zone's soil element was divided into three groups. In the L.chuanxiong cultivation experiments, we found Ligustilide in rhizomes was positively related to Se and Sr and negatively related to Mn and the chemical elements. This study successfully verified that the medicinal plant's Daodi-zone has a natural boundary, and L.chuanxiong's Daodi-zone may be from east of Dujiangyan to the west edge of Longquan, rich in Na, Mg, K and Low Mn is the soil characteristics of the area. Moreover, we put forward a method to identify L.chuanxiong's Daodi-zone based on characteristic soil elements, which can also provide a practical basis for dividing other economic plants' growth environment.