• Korean Journal of Plant Taxonomy
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• v.51 no.3
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• pp.192-197
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• 2021

In the flora of Korea, Carex L. is one of the most species-rich genera. Among nearly 157 Carex taxa, less than 30 have had chromosome numbers reported. We report the meiotic chromosome numbers of eight Carex taxa from Korean populations, which include the first count for C. accrescens Ohwi (n = 37_II) and the first chromosome investigations of Korea populations for three taxa: C. bostrychostigma Maxim. (n = 22_II), C. lanceolata Boott (n = 36_II), and C. paxii Kuk. (n = 38_II). In most species, chromosome counts observed in the study are included in the variation ranges of previous chromosome numbers. However, C. bostrychostigma Maxim. (n = 22_II) and C. planiculmis Kom. (n = 29_II) are assigned new chromosome numbers. Carex is known to have holocentric chromosomes, lacking visible primary constrictions and exhibiting great variance in its chromosome number. Further investigations of the diversity of Carex chromosomes will provide basic information with which to understand the high species diversity of the genus.

• Korean Journal of Plant Taxonomy
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• v.48 no.4
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• pp.260-277
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• 2018

The evolution of chromosome numbers and the karyotype structure is a prominent feature of plant genomes contributing to or at least accompanying plant diversification and eventually leading to speciation. Polyploidy, the multiplication of whole chromosome sets, is widespread and ploidy-level variation is frequent at all taxonomic levels, including species and populations, in angiosperms. Analyses of chromosome numbers and ploidy levels of 252 taxa of Korean non-commelinid monocots indicated that diploids (ca. 44%) and tetraploids (ca. 14%) prevail, with fewer triploids (ca. 6%), pentaploids (ca. 2%), and hexaploids (ca. 4%) being found. The range of genome sizes of the analyzed taxa (0.3-44.5 pg/1C) falls well within that reported in the Plant DNA C-values database (0.061-152.33 pg/1C). Analyses of karyotype features in angiosperm often involve, in addition to chromosome numbers and genome sizes, mapping of selected repetitive DNAs in chromosomes. All of these data when interpreted in a phylogenetic context allow for the addressing of evolutionary questions concerning the large-scale evolution of the genomes as well as the evolution of individual repeat types, especially ribosomal DNAs (5S and 35S rDNAs), and other tandem and dispersed repeats that can be identified in any plant genome at a relatively low cost using next-generation sequencing technologies. The present work investigates chromosome numbers (n or 2n), base chromosome numbers (x), ploidy levels, rDNA loci numbers, and genome size data to gain insight into the incidence, evolution and significance of polyploidy in Korean monocots.

• Korean Journal of Plant Taxonomy
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• v.50 no.3
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• pp.361-367
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• 2020

We report meiotic chromosome numbers of three taxa in Carex sect. Mitratae in Korea: Carex breviculmis R. Br. (n = 32_II, 33_II, 34_II), C. polyschoena H. Lév. & Vaniot (n = 37_II, 38_II), and C. sabynensis Less. ex Kunth (n = 27_II). Section Mitratae is one of the most species-rich Asian groups in Carex, comprising approximately 45-80 taxa. Twenty-seven of these occur in Korea, and they are some of the most challenging taxa to identify due to their obscure and inconspicuous diagnostic characters. Including the counts reported here, half of the native Korean sect. Mitratae chromosome numbers have been documented. Their haploid chromosome numbers range from n = 10 to n = 40, and many exhibit variations in the numbers counted within a taxon. These variations, along with the overall significant variation in sect. Mitratae, suggest that dynamic chromosome activity may be related to the high species diversity of Carex.

• Korean Journal of Plant Resources
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• v.10 no.4
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• pp.292-299
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• 1997

The somatic chromosome numbers among the various taxonomic characters about 17 taxa in Korean Aster and its allied taxa were investigated to review accurate scientific name and taxonomic rank. The somatic chromosome numbers of the treated taxa were invariable in same taxa, but variable among different taxa. The treated taxa were divided into two types by basic chromosome numbers, one type was x=9, the other x=8 and x=9 type was subdivided by polyploidy. The somatic chromosome numbers of Aster altaicus var. uchiymae, A. hyatae, Kalimeris chejuensis were reported firstly in this study, and based upon somatic chromosome numbers and leaf morphology, the plants, idenified as Aster pinnatifidus in Korea was considered variant of Kalimeris incisa.

• Korean Journal of Plant Taxonomy
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• v.48 no.3
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• pp.201-205
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• 2018

Carex L. (Cyperaceae) is the largest angiosperm genus in the temperate zones with more than 2,000 species worldwide. Unusual chromosome structures, called holocentric chromosomes, have been postulated to contribute to species diversity in the genus. In Korea, this genus has the greatest number of species, but chromosome information as it pertains to the taxa is mostly unknown. Here, we report meiotic chromosome numbers of five Carex taxa in Korea. The following observations are made: Carex jaluensis Kom. ($n=27_{II}$, $28_{II}$, $29_{II}$, $30_{II}$), C. japonica Thunb. ($n=28_{II}$, $29_{II}$), C. planiculmis Kom. ($n=30_{II}$), C. miyabei Franch. ($n=33_{II}$, $36_{II}$), C. neurocarpa Maxim. ($n=51_{II}$, $53_{II}$, $54_{II}$). Except for C. planiculmis, all of the species exhibit variations in chromosome numbers within individuals and/or taxa. The findings with regard to chromosome number diversity in Carex suggest that chromosome number variation (aneuploidy, agmatoploidy and/or symploidy) plays an important role in the richness of the species in the genus. Further cytological investigations are needed for a better understanding of sedge diversity in Korean flora.

• Korean Journal of Plant Taxonomy
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• v.41 no.3
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• pp.215-222
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• 2011

Various aneuploidy and polyploidy have been reported in the genus Aconitum L. (ca. 300 species worldwide, Ranunculaceae), and there is a demonstrated association between major lineage diversification and polyploidy. This study reports chromosome counts of eight Aconitum from Korea, including the first counts for A. japonicum Thunb. subsp. napiforme ($H. L{\acute{e}}v.$ & Vaniot) Kadota (2n = 32) and A. longecassidatum Nakai (2n = 16). The study also includes chromosome numbers for two taxa on the Critically Endangered species list in Korea. Among Korean native species, chromosome numbers in Aconitum subgenus Aconitum range from 2n = 16 to 2n = 64 with diverse levels of polyploidy (2x, 4x, and 8x), whereas Aconitum subg. Lycoctonum exhibits only diploids (2n = 16). Greater chromosome number diversity in subg. Aconitum than subg. Lycoctonum might explain higher species diversity within the former subgenus (more than 250 species worldwide). Investigating chromosome number diversity of Aconitum in a phylogenetic framework will be a critical step to understand species richness of the genus.

• Korean Journal of Plant Taxonomy
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• v.39 no.4
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• pp.247-253
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• 2009

Somatic chromosome numbers for 20 taxa of Korean Artemisia L. were investigated for the purpose of classification. Somatic chromosome numbers of treated taxa were 2n = 16, 18, 34, 36, 50, 52, 54, and therefore their basic chromosome numbers were x = 8, 9, 10, 13, 17. The chromosome number of A. japonica var. angustissima is being reported for the first time in this study. The chromosome numbers of 13 taxa were the same as in previous reports; A. capillaris (2n = 18), A. japonica var. hallaisanensis (2n = 36), A. japonica subsp. littoricola (2n = 36), A. annua (2n = 18), A. carvifolia (2n = 18), A. fukudo (2n = 16), A. keiskeana (2n = 18), A. stolonifera (2n = 36), A. sylvatica(2n = 16), A. selengensis (2n = 36), A. montana (2n = 52), A. lancea (2n = 16), A. sieversiana (2n = 18); however, the chromosome numbers of 6 taxa were different; A. japonica var. japonica (2n = 18, 36 vs 2n = 36), A. sacrorum (2n = 18, 54 vs 2n = 54), A. rubripes (2n = 16, 34 vs 2n = 16), A. indica (2n = 34, 36 vs 2n = 34), A. codonocephala (2n = 18, 50, 54 vs 2n = 50), A. argyi (2n = 34, 36, 50 vs 2n =34). The somatic chromosome numbers of Korean Artemisia are thought to be good characteristics for classifying some taxa such as A. japonica var. japonica, A. sacrorum, A. codonocephala, A. argyi, A. montana, A. sylvatica.

• Korean Journal of Medicinal Crop Science
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• v.16 no.3
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• pp.161-167
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• 2008

New somatic chromosome numbers and karyotype analyses of 33 medicinal herbs (30 genera, 23 families) in Korea were investigated. The chromosome numbers of 4 taxa, Euryale ferox, Rodgersia podophylla, Cirsium japonicum var. ussurience, Eehinops setifer, showed results that are different from previous reports. Among 33 taxa, 23 taxa were reported for the first time, and karyotype analyses were newly conducted for 2 taxa (Tiarella polyphylla, Crepidiastrum denticulatum) in Korea. In addition, we observed for the first time the new chromosome numbers for 4 taxa distributed evenly over the world (Lindera erythrocarpa, Corylopsis glabrescens var. gotoana, Ardisia crenata, Callicarpa japonica var. luxurians).

• Korean Journal of Plant Taxonomy
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• v.49 no.3
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• pp.269-273
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• 2019

We report the meiotic chromosome numbers of four Carex taxa from Korean populations. Three are the first reports made on taxa from Korean populations: Carex appendiculata (Trautv. & C. A. Mey.) $K{\ddot{u}}k$. ($n=27_{II}$), C. fernaldiana H. $L{\acute{e}}v$. & Vaniot ($n=33_{II}$), and C. metallica H.$L{\acute{e}}v$. ($n=15_{II}$). Reports on the other species expand the range of variation in the chromosome number within a taxon, C. miyabei Franch. (n = $43_{II}$, $44_{II}$, $45_{II}$). Carex L. (Cyperaceae) consists of more than 2,000 species worldwide and is the most species-rich genus in Korea. The species diversity in the genus has been hypothesized to be associated with the chromosome variation, but chromosome information pertaining to Korean Carex taxa is not well known. This report updates the chromosome number inventory on Korean Carex to 24 out of 180 taxa.

• Plant Resources
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• v.3 no.3
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• pp.179-183
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• 2000

The present study was carried out to clarify the chromosome numbers and karyotype of Atractylodes japonica Koidz. ex Kitam. and A. macrocephala Koidz.. The somatic chromosome numbers of two species were same; basic chromosome number x=12, and somatic chromosome numbers 2n=24. The present result of A. japonica Koidz. ex Kitam. was same to previously reports and that of A. macrocephala Koidz. was reported first in this study. Size and shape of chromosome were some different from A. japonica Koidz. ex Kitam. and A. macrocephala Koidz.. The karyotype of A. japonica Koidz. ex Kitam. was described as follows; 2n : 24 : 8L + 14M +2S : 2 $A^{sm}$ +2 $B^{m}$ +2 $C^{m}$ +2 $D^{st}$ + 2 $E^{m}$ +2 $F^{m}$ +2 $G^{m}$ +2 $H^{sm}$ + 2 $I^{m}$ + 2 $J^{m}$ + 2 $K^{m}$ + 2 $L^{m}$ . And the karyotype of A. macrocephata Koidz. was described as follows; 2n : 24 : 10L +12M +25 : 2 $A^{m}$ +2 $B^{sm}$ +2 $C^{sm}$ +2 $D^{sm}$ +2 $E^{sm}$ +2 $E^{sm}$ +2 $G^{sm}$ +2 $H^{m}$ +2 $I^{m}$ 2 $J^{m}$ +2 $K^{m}$ +2 $L^{m}$ . .