Hyoung-Tak Im

Floristic Study of Mt. Mudeung

We investigated the flora of Mudeung-san (Mt.) located in Gwangju-gwangyeoksi, Hwasun-gun and Damyang-gun and discussed the vascular plants found there. 22 days separate fild trips were completed from March of 2009 to November 2011. As a result, we identified the distribution of 816 taxa in Mudeung-san (Mt.), comprising 123 families, 441 genera, 668 species, 5 subspecies, 121 varieties and 18 forms. There are a total 111 taxa of floristic regional indicator plants. The floristic regional indicator plants are as follows; nine taxa of level V such as Gastrodia elata Blume, six taxa of level IV such as Hylomecon hylomeconoides T. Lee, 21 taxa of level III such as Stewartia korena Nakai, 18 taxa of level II, and 66 taxa of level I. In addition, two critically endangered species (CR), Galeola septentrionalis Rchb.f. and Paeonia obovata Maxim., two endangered species (EN), Dryopteris cycadina (Franch. & Sav.) C.Chr. and Jeffersonia dubia Benth., and eight vulnerable species (VU), such as Lilium callosum Siebold & Zucc, were found in the investigated area. Also, 14 endermic plants of Korea, such as Salix koriyanagi Kimura and Aconitium chiisanense Nakai, were found.

Exploring data processing strategies in NGS target enrichment to disentangle radiations in the tribe Cardueae (Compositae)

Target enrichment is a cost-effective sequencing technique that holds promise for elucidating evolutionary relationships in fast-evolving lineages. However, potential biases and impact of bioinformatic sequence treatments in phylogenetic inference have not been thoroughly explored yet. Here, we investigate this issue with an ultimate goal to shed light into a highly diversified group of Compositae (Asteraceae) constituted by four main genera: Arctium, Cousinia, Saussurea, and Jurinea. Specifically, we compared sequence data extraction methods implemented in two easy-to-use workflows, PHYLUCE and HybPiper, and assessed the impact of two filtering practices intended to reduce phylogenetic noise. In addition, we compared two phylogenetic inference methods: (1) the concatenation approach, in which all loci were concatenated in a supermatrix; and (2) the coalescence approach, in which gene trees were produced independently and then used to construct a species tree under coalescence assumptions. Here we confirm the usefulness of the set of 1061 COS targets (a nuclear conserved orthology loci set developed for the Compositae) across a variety of taxonomic levels. Intergeneric relationships were completely resolved: there are two sister groups, Arctium-Cousinia and Saussurea-Jurinea, which are in agreement with a morphological hypothesis. Intrageneric relationships among species of Arctium, Cousinia, and Saussurea are also well defined. Conversely, conflicting species relationships remain for Jurinea. Methodological choices significantly affected phylogenies in terms of topology, branch length, and support. Across all analyses, the phylogeny obtained using HybPiper and the strictest scheme of removing fast-evolving sites was estimated as the optimal. Regarding methodological choices, we conclude that: (1) trees obtained under the coalescence approach are topologically more congruent between them than those inferred using the concatenation approach; (2) refining treatments only improved support values under the concatenation approach; and (3) branch support values are maximized when fast-evolving sites are removed in the concatenation approach, and when a higher number of loci is analyzed in the coalescence approach.

Two complete chloroplast genomes of an endangered orchid species, Pelatantheria scolopendrifolia (Orchidaceae), in Korea

Abstract We determined the complete chloroplast genome sequence of two individuals of Pelatantheria scolopendrifolia, an endangered orchid species in Korea. The total chloroplast genome size of Mokpo (MG752972) and Naju (MG752973) population was 146,971 bp and 146,848 bp, respectively. The chloroplast genome contained 106 genes, including 72 protein-coding genes, 30 tRNA genes, and four rRNA genes. Variation in gene contents and structures was not found between two individuals. We found truncated or deleted ndh genes in P. scolopendrifolia. Phylogenetic analysis, based on the whole chloroplast genome sequences of 25 species of Orchidaceae, showed that P. scolopendrifolia was most closely related to Gastrochilus fuscopunctatus.

Pollination biology of Caesalpinia decapetala (Leguminosae) in Korea

【Morphological changes of flowers and insect visitors were observed to investigate pollinator of Caesalpinia decapetala. The flowers of C. decapetala are protandrous. Functionally, the flower is changed from male to female. As a male, pollen grain is released after anther dehisced while style is immature. After completed pollen grain release, the style starts to lengthen. It helps the stigma to easily touch the carpenter bees thorax covered with pollen grain. At this time, flower functions as a female. The majority of taxa and individuals observed were Hymenoptera. The most frequent visitor was the Xylocopa appendiculata circumvolans, carpenter bee. Carpenter bees exhibited only typical pollinator behavior among flower visitors, with touching reproductive organs and seeking nectar at the same time. The pollination behavior is as follows. Soon after carpenter bees perceived guide mark, they foraged rightward and grasped style and stamens with legs and they inserted proboscis into standard petal to seek nectar. With this behavior, the pollen grains of the male flower transfer to the ventral thorax of the carpenter bee. As the carpenter bee moves to another female flower, the deposited pollen grains are delivered to the stigma.】

Floristic study of Jang-do (Isl.) in Korea

We investigated the flora of Jang-do (Isl.), an island of the Heuksan archipelago, located in Heuksan-myeon, Shinan-gun, Jeollanam-do and discussed the remarkable plants found there. Thirteen-field trips (total 27 days) were completed from May of 2004 to May of 2013. As a result, we identified the distribution of 423 taxa in Jang-do (Isl.), comprising 104 families, 285 genera, 335 species, 78 varieties and 10 forms. There are a total of 95 taxa of floristic regional indicator plants. The floristic regional indicators are as follows; four taxa of level V such as Impatiens furcillata, four taxa of level IV such as Hosta yingeri, 14 taxa of level III such as Ophioglossum vulgatum, 5 taxa of level II, and 58 taxa of level I. In addition 10 red data plants, 2 vulnerable species (VU) including Calanthe striata for. sieboldii, and 4 least concern species (LC) like Ardisia crenata, 2 not evaluated species (NE) such as Hosta yingeri, were found in the investigated area. An unrecorded species, Fragaria (Rosaceae), was found in a forest of Jang-do (Isl.) for the first time in Korea.