Abstract Detail

Systematics Section/ASPT

Yun, Seon A [1], Lee, Chunghee [2], Im, Hyoung-Tak [3], Kim, Seung-Chul [4].

Preliminary phylogenetic analysis of genus Saussurea (Asteraceae; Cardueae) in Korea inferred from nuclear ITS and chloroplast trnL-F sequence data.

The genus Saussurea (ca. 400 species) is one of the largest in the tribe Cardueae and is widely distributed throughout the Holarctic. The greatest number of species and morphological diversity in Saussurea are found in the Sino-Himalaya and Central Asia. Although tremendous morphological variation exists within the genus, Saussurea can be distinguished from other related genera by having linear style branches and dimorphic pappus bristles. It has been a difficult challenge to produce comprehensive infrageneric classification system of the genus due in part to its large size and wide distribution. Various infrageneric classifications have been proposed and, in the most recent monograph by Lipschits (1979), six subgenera were recognized; Jurinocera, Eriocoryne, Amphilaena, Theodorea, Frolovia, and Saussurea. Only a handful of molecular phylogenetic studies have been conducted to elucidate phylogenetic relationships within the genus. In the most recent floristic treatment of Korea, about 34 species have been recognized without infrageneric and sectional classification. In this study, we sampled 15 species of Saussurea in Korea including six endemic taxa and accessed their phylogenetic relationships. We sequenced both nrDNA ITS and chloroplast trnL-F noncoding regions and conducted a broad phylogenetic analysis (MP and ML) including representative lineages within the genus. In the case of cpDNA trnL-F phylogeny (83 taxa x 867 chars.), all but two subgenera (Jurinocera and Frolovia) are highly polyphyletic. At least six lineages of Saussurea in Korea can be recognized and each lineage shares its most recent common ancestor with members of subgenera Eriocoryne, Saussurea, and Theodorea. On the contrary, the ITS phylogeny (110 taxa x 660 chars.) suggested that S. maximowiczii shares its most recent common ancestor with the species in Central and East Asia, and is distantly related to the remaining species in Korea. Two species of subgenus Amphilaena from Central/East Asia is sister to the remaining monophyletic group in Korea. This may suggest that Saussurea species underwent rapid radiation after the common ancestor evolved in Korea. The incongruence between ITS and cpDNA phylogeny with regard to the species of Saussurea in Korea is striking and a lineage sorting of ancestral cpDNA polymorphism could cause this major incongruence. An alternative hybridization hypothesis and concerted evolution of ITS sequences will also be evaluated. The independent evolution of limestone endemic species in Korea is inferred based on ITS and cpDNA phylogeny.

1 - Sungkyunkwan University, Biological Sciences, 2066 Seobu-ro, Suwon, Gyeong-Gi, 440-746, Korea
2 - Korea National Arboretum, 415 Gwangneung Soomokwon-ro, Pocheon, Gyeong-Gi, 487-821, Korea
3 - Chonnam National University, Biology, Kawangju, 500-757, Korea
4 - Sungkyunkwan University, Biological Sciences, 2066 Seobu-ro, Suwon, Gyeonggi Do, N/A, 440-746, Korea

Keywords:
Saussurea
Cardueae
Asteraceae
Korea
Phylogenetic classification
nrDNA ITS
trnL-F intergenic spacer.

Presentation Type: Poster:Posters for Sections
Session: P
Location: Eyrie/Boise Centre
Date: Monday, July 28th, 2014
Time: 5:30 PM
Number: PSY042
Abstract ID:179
Candidate for Awards:None