Plant Diversity ›› 2022, Vol. 44 ›› Issue (06): 519-529.DOI: 10.1016/j.pld.2022.06.002

• Research paper •     Next Articles

Plastome characteristics and species identification of Chinese medicinal wintergreens (Gaultheria, Ericaceae)

Yan-Ling Xua, Hao-Hua Shena, Xin-Yu Dub, Lu Lua   

  1. a. School of Pharmaceutical Sciences and Yunnan Key Laboratory of Pharmacology for Natural Products, Kunming Medical University, Kunming, Yunnan, China;
    b. Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan, China
  • Received:2022-04-12 Revised:2022-06-01 Online:2022-11-25 Published:2022-12-13
  • Contact: Xin-Yu Du,;Lu Lu,
  • Supported by:
    This research was co-supported by the National Natural Science Foundation of China (31960080, 41671052 and 42175139), the Reserve Talents of Young and Middle-aged Academic and Technical Leaders in Yunnan province (202005AC160020), and the Program Innovative Research Team in Science and Technology in Yunnan Province (202005AE160004).

Abstract: Wintergreen oil is a folk medicine widely used in foods, pesticides, cosmetics and drugs. In China, nine out of 47 species within Gaultheria (Ericaceae) are traditionally used as Chinese medicinal wintergreens; however, phylogenetic approaches currently used to discriminating these species remain unsatisfactory. In this study, we sequenced and characterized plastomes from nine Chinese wintergreen species and identified candidate DNA barcoding regions for Gaultheria. Each Gaultheria plastome contained 110 unique genes (76 protein-coding, 30 tRNA, and four rRNA genes). Duplication of trnfM, rps14, and rpl23 genes were detected, while all plastomes lacked ycf1 and ycf2 genes. Gaultheria plastomes shared substantially contracted SSC regions that contained only the ndhF gene. Moreover, plastomes of Gaultheria leucocarpa var. yunnanensis contained an inversion in the LSC region and an IR expansion to cover the ndhF gene. Multiple rearrangement events apparently occurred between the Gaultheria plastomes and those from several previously reported families in Ericales. Our phylogenetic reconstruction using 42 plastomes revealed well-supported relationships within all nine Gaultheria species. Additionally, seven mutational hotspot regions were identified as potential DNA barcodes for Chinese medicinal wintergreens. Our study is the first to generate complete plastomes and describe the structural variations of the complicated genus Gaultheria. In addition, our findings provide important resources for identification of Chinese medicinal wintergreens.

Key words: DNA barcodes, Gene duplication, Plastome, Repeat sequences, Structural variation