Changkyun Kim

Conservation genetics of endangeredBrasenia schreberi based on RAPD and AFLP markers

Brasenia schreberi J.F. Gmelin is a declared endangered species found in the lakes and ponds of South Korea. For planning its conservation strategy, we examined the genetic diversity within and among six populations, using randomly amplified polymorphic DNA (RAPD) and amplified fragment length polymorphism (AFLP). Polymorphisms were more frequently detected per loci with AFLP (69.3%) than RAPD (36.8%). High genetic diversity was recognized within populations: polymorphic loci (PPL) values ranged from 36.3% in the CJM population to 74.5% in the GGT population, with a mean value of 47.8% based on AFLP markers. Great genetic differentiation (θB) was detected among the six populations (0.670 on RAPD and 0.196 on AFLP), and we calculated a low rate of gene flow (Nem), i.e., 0.116 on RAPD and 0.977 on AFLP. Furthermore, a Mantel test revealed that no correlation existed between genetic distances and geographical distances among the six local populations, based on RAPD or AFLP markers. These results are attributed to a number of factors, including an insufficient length of time for genetic diversity to be reduced following a natural decline in population size and isolation, adaptation of the genetic system to small population conditions, and a restricted gene flow rate. Based on both its genetic diversity and population structure, we suggest that a strategy for conserving and restoringB. schreberi must focus on maintaining historical processes, such as high levels of outbreeding, while monitoring increased gene flow among populations. This is because a reduction in genetic diversity as a result of genetic drift is undesirable.

Speciation pathway of Isoetes (Isoetaceae) in East Asia inferred from molecular phylogenetic relationships.

Polyploidy plays an important role in the speciation of Isoëtes. Increasing our knowledge about the specific origin of each polyploid or phylogenetic relationship among species has been hampered because of conserved morphological variation and scarce habitats. We present several hypotheses concerning the speciation pathways of Isoëtes species distributed in East Asia. Our hypotheses are inferred from phylogenetic relationships that were elucidated using sequences of the internal transcribed spacer regions of nuclear ribosomal DNA, a second intron of LEAFY, and chloroplast DNA trnS-psbC spacer regions. These inferred phylogenetic relationships indicated that (1) the Chinese tetraploid, I. sinensis, is closely related to I. yunguiensis; (2) the Korean endemic species, I. hallasanensis, is an autotetraploid derived from I. taiwanensis or closely related taxa; (3) the hexaploid I. coreana forms a clade and has its closest evolutionary relationships with I. taiwanensis or I. hallasanensis; and (4) the Japanese hexaploid I. japonica is closely related to I. taiwanensis-I. coreana and I. sinensis-I. yunguiensis. These results suggest that interspecific hybridization and polyploidization have played central roles in speciation of East Asian Isoëtes. Furthermore, I. taiwanensis, an endemic species in Taiwan, has been involved in at least three cases of autopolyploid or allopolyploid speciation in East Asia.

A phenetic analysis of Typha in Korea and far east Russia.

We used principal components analysis (PCA) and UPGMA cluster analysis to determine taxonomically definable limits and to estimate the phenetic relationships among four Typhaspecies from Korea and far east Russia using 25 quantitative characters. A scatter plot of the first two principal components resolved four clusters among the 77 specimens of Typha examined from Korea and far east Russia. The clusters corresponded to the four currently recognized species. Typha latifolia was readily distinguished from other species by having wide leaves and female inflorescences. Typha angustifolia was distinguished from T. orientalis and T. laxmanni by the long male inflorescences and large gap between male and female inflorescences. Typha laxmanniwas distinguished from T. orientalis by a higher ratio of male and female inflorescence lengths than others. UPGMA analysis also showed that individuals of Typha species from Korea and far east Russia form discrete clusters corresponding to four species.

Genetic diversity and population structure of diploid and polyploid species of Isoëtes in East Asia based on amplified fragment length polymorphism markers.

Isoëtes L. is critically endangered in areas of East Asia, including Taiwan, Japan, and South Korea. The genetic diversity and the population structure of six Isoëtes species from East Asia were evaluated by using amplified fragment length polymorphism (AFLP). Three AFLP‐selective primer combinations generated a total 923 amplification products, of which 919 (99.6%) were polymorphic. The levels of genetic diversity of two diploid species (I. taiwanensis [percentage of polymorphic loci \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \usepackage[OT2,OT1]{fontenc} \newcommand\cyr{ \renewcommand\rmdefault{wncyr} \renewcommand\sfdefault{wncyss} \renewcommand\encodingdefault{OT2} \normalfont \selectfont} \DeclareTextFontCommand{\textcyr}{\cyr} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} \landscape

Molecular genotyping of Trapa bispinosa and T. japonica (Trapaceae) based on nuclear AP2 and chloroplast DNA trnL-F region.

( \mathrm{PPL}\,) =33.1\% {\mbox{--}} 38.3\%

Molecular reexamination of korean umbelliferae based on internal transcribed spacer sequences of rDNA:Ligusticum tenuissimum (Nakai) Kitagawa andLibanotis coreana (Wolff) kitagawa

\end{document} ] and I. asiatica [ \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \usepackage[OT2,OT1]{fontenc} \newcommand\cyr{ \renewcommand\rmdefault{wncyr} \renewcommand\sfdefault{wncyss} \renewcommand\encodingdefault{OT2} \normalfont \selectfont} \DeclareTextFontCommand{\textcyr}{\cyr} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} \landscape

Cloning and structural analyses of partial nuclear rDNA fromBupleurum euphorbioides (Apiaceae)

\mathrm{PPL}\,=49.0\%