An unexpected genetic diversity pattern and a complex demographic history of a rare medicinal herb, Chinese asparagus (Asparagus cochinchinensis) in Korea

Authors: LEE, SOO-RANG - Hallym University; PARK, HAN-SOL - National Institute Of Research And Development For Food Bioresources; KIM, BO-YUN - Hallym University; LEE, JUNG HOON - Hallym University; Gaskin, John; KIM, YOUNG-DONG - Hallym University

Submitted to: Nature Scientific Reports
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/5/2019
Publication Date: 7/5/2019
Citation: Lee, S., Park, H., Kim, B., Lee, J., Gaskin, J.F., Kim, Y. 2019. An unexpected genetic diversity pattern and a complex demographic history of a rare medicinal herb, Chinese asparagus (Asparagus cochinchinensis) in Korea. Nature Scientific Reports. 9:9757.

Interpretive Summary: Asparagus cochinchinensis, a medicinally important perennial herb, is in decline due to overharvesting in Korea. Eight A. cochinchinensis populations in Korea and three neighboring countries (China, Japan and Taiwan) were genetically examined and suggest that there are two evolutionary lineages that split about 30,000 years ago. The two lineages were independently introduced to Korea within ~150 years and then hybridized. The estimated time of introduction and evolutionary history inferred are supported by historical records and the present day distribution pattern. Our results provide critical information for cultivation and conservation practices. The two lineages found in our study might have different habitat preferences and growth conditions, thus they should be considered not only in conservation and management studies but also in agricultural use.

Technical Abstract: Range-wide population studies for wide spread species are often associated with a complex diversity pattern resulting from genetically divergent evolutionary significant units (ESUs) or cryptic species. A compound evolutionary history might result in a divergence pattern that can be inferred through molecular analyses. Asparagus cochinchinensis, a medicinally important perennial herb, is in decline due to overharvesting in Korea. Eight A. cochinchinensis populations in Korea and three neighboring countries (China, Japan and Taiwan) were examined using 9 microsatellite loci to characterize population structure. Clustering analyses and approximate Bayesian Computation (ABC) suggested that there are two ESUs that split about 30,000 BP. The two ESUs were independently introduced to Korean within ~150 years and admixed in secondary contact zones. The estimated time of introduction? and evolutionary history inferred are supported by historical records and the present day distribution pattern. Our results provide critical information for cultivation and conservation practices. The two ESUs found in our study might have different habitat preferences and growth conditions, thus the two genetically divergent groups should be considered not only in conservation and management studies but also in agricultural use.