Abstract Detail

Hybrids and Hybridization

Gil, Hee-Young [1], Pimenova, Elena [2], Maki, Masayuki [3], Taran, Aleksandr [4], Kim, Seung-Chul [1].

Hybridization and anagenesis on Ulleung Island: case studies of violet and figwort.

Ulleung Island, an oceanic volcanic island in Korea, is home for ca. 500 native species of vascular plants with about 8% (40 species) endemism. The Ulleung Island has been recognized as an excellent model system to study the pattern and process of early stages of flowering plant evolutions on oceanic island. The predominant mode of speciation on Ulleung Island is considered anagenetic speciation (88%), while the important role of reticulate evolution (e.g., Aster chusanensis) is poorly documented. In this presentation, we introduce and discuss two different cases of generating biodiversity on island, hybridization and anagenetic speciation, on Ulleung Island. One example of hybridization includes Viola woosanensis (Violaceae), which is purportedly hybrid origin between V. ulleungdoensis and V. chaerophylloides. We determined that V. woosanensis is of hybrid origin with maternal parent of V. ulleungdoensis and paternal parent of V. chaerophylloides. We found perfect additive polymorphisms in ITS sequences, suggesting that V. woosanensis is early generation of hybrid species. Multiple and unidirectional hybrid origin of V. woosanensis is suggested and asymmetry of reproductive isolation between two parental species requires further study. The evolutionary fate of this hybrid is yet to be determined. Another case is Scrophularia takesimensis, critically endangered endemic species in Ulleung Island. We conducted molecular phylogenetic analyses to determine the origin of S. takesimensis with thorough sampling from eastern Asia. Previously sequenced representative species of Scrophularia were combined with our data set and analyzed. The global scale ITS phylogeny suggested that three eastern Asia species are monophyletic, but surprisingly, S. takesimensis was more closely related to the clade containing eastern North American/Caribbean species rather than to either S. alata or S. grayanoides. The global scale cpDNA phylogeny demonstrated that the eastern North America/Caribbean clade is sister to the clade containing three eastern Asian species. In addition, the monophyletic S. takesimensis is deeply embedded within paraphyletic S. alata, sharing its most recent common ancestor with populations from Japan (2n=94). Geographically structured two divergent cp haplotype groups within S. takesimensis may suggest at least two independent introductions from different source areas. The phylogenetic incongruence between nuclear and chloroplast genomes, polyploidization and aneuploidization of S. takesimensis (2n=80) and closely related species, and unusual intercontinental disjunct distribution require further detailed independent nuclear genealogical, cytological, and biogeographic analyses.

1 - Sungkyunkwan University, Biological Sciences, Seobu-ro 2066, Jangan-gu, Suwon, KOREA
2 - Botanical Garden-Institute FEB RAS, Vladivostok, Russia
3 - Tohoku University, Division of Ecology and Evolutionary Biology, Graduate School of Life Sciences, Sendai, Japan
4 - Sakhalin Branch of Botanical Garden-Institute FEB RAS, Yuzhno-Sakhalinsk, Russia

Keywords:
hybridization
anagenesis
Ulleung Island.

Presentation Type: Oral Paper
Session: 50, Hybrids and Hybridization
Location: 102/Savannah International Trade and Convention Center
Date: Wednesday, August 3rd, 2016
Time: 4:00 PM
Number: 50002
Abstract ID:78
Candidate for Awards:None