Composition and diversity of microbial endophytes in roots, stems, and leaves of Angelica sinensis in three main planting areas

Abstract

Angelica sinensis, a perennial medicinal herb, of which the dried roots are often used in traditional Chinese medicine to treat complex medical conditions. As medicinal plants and their endophytes are a symbiotic whole, a diverse range of endophytes play an important role in the growth and metabolism of the host medicinal plant. To explore the composition and diversity of endophytes in the tissues of A. sinensis growing in different geographical regions, the fungal and bacterial communities of the roots, stems and leaves of A. sinensis growing in three different production areas based on high throughput sequencing technology were characterized in this study. Results showed that in the Zhangxian area, the dominant endophytic fungal genera were Inocybe (74.00%), Septoria (73.27%) and Ceriporia (26.36%) and the dominant bacterial genera were Muribaculaceae (5.85%), taxa PB19 (6.38%) and Bacteroides (4.83%) in the tissues of A. sinensis. In the Minxian area, Inocybe (89.65%) and Alternaria (26.85%) were the prominent fungal genera and Muribaculaceae (8.23%) and taxa PB19 (5.58%) were the main bacterial genera. The predominant fungal genera in the Tanchang area were Thanatephorus (78.76%), Septoria (42.48%) and Inocybe (20.10%) and the predominant bacterial genera were taxa PB19 (6.18%), Muribaculaceae (5.43%) and Marivita (4.92%). Additionally, Inocybe was the most abundant fungal genus associated with the roots and stems of A. sinensis and Septoria was the most abundant fungal genus associated with the leaves of A. sinensis. Pseudomonas, Muribaculaceae, and taxa PB19 exhibited the highest abundance in the roots, stems and leaves of A. sinensis, respectively. The composition and abundance of endophytic microbial communities were tissue-, organ- and sampling area-dependent. Wilcoxon signed-rank test and Pearson correlation analysis of A. sinensis tissue samples revealed that different habitat and type of tissues and sampling areas influenced endophytic microbial community structures. Furthermore, principal co-ordinate analysis revealed that the endophytic bacterial compositions of the different tissue samples of A. sinensis from the three sampling areas were considerably different. By contrast, differences in fungal composition in the roots, stems and leaves of A. sinensis were only detected in the Tanchang area. The study contributes to understanding the community structure of endophytes associated with A. sinensis, and ascertaining the influence of geographic regions and ecological niches on the microbial communities, and also provides a theoretical basis for the rational development of the endophyte resources to improvement of the quality and enhancement of the comprehensive utilization value of A. sinensis.