Abstract: Continuous cropping causes Angelica sinensis (DG) medicinal yield to reduce year by year. In order to study the effects of crop rotation patterns on soil factors and the medicinal yield of A. sinensis, data on relevant soil and yield factors were collected from residue sites where A. sinensis is grown in rotation with other medicinal crops such as Gentiana macrophylla (QJ-DG) and Notopterygium incisum (QH-DG), and compared with data from sites where A. sinensis is grown in continuous cropping systems (DG-DG, or control). The data were assessed by membership function and cluster analysis so to provide an objective basis for classifying the rotation pattern. It was found that the rotation patterns had significant effects on the soil properties and the medicinal yield of A. sinensis. The QJ-DG rotations effectively improved the soil properties, resulting in higher organic matter, but lower total K and P. Notably, increased soil organic matter in these systems was linked to improved soil water retention which in turn increased patent medicine plant rate by 94.10%, fresh individual root weight by 53.46% and total fresh medicinal yield by 125.56%, compared with DG-DG. However, in contrast, QH-DG rotations showed higher pH and lower total organic content, but higher organic content rich in P and K, and lower soil water retention appeared in the DG-DG control sites. Thus data from all sites were clustered into three categories ranked for medicinal productivity of A. sinensis as QJ-DG>DG-DG>QH-DG and comprehensive scored as QJ-DG (0.8132)>QH-DG (0.3315)>DG-DG (0.2051) in the cluster analysis. In summary, the crop rotation used has affected soil properties and growing A. sinensis in rotation with G. macrophylla improved the soil environment, resulting in the higher medicinal root yield.

Key words: Angelica sinensis, rotation pattern, soil property, medical yield