• 한국식물생명공학회:학술대회논문집
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• 한국식물생명공학회 2005년도 추계학술대회 및 한일 식물생명공학 심포지엄
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• pp.112-119
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• 2005

Efficient plant regenerationsystem from cell suspension cultures was established in D. acicularis (2n = 90) by monitoring ploidy level and visual selection of the cultures. The highly regenerable cell lines selected maintained original ploidy level and consisted of compact cell clumps with yellowish color and relatively moderate growth, suggesting that it is possible to select visually the highly regenerable cell lines with the original ploidy level. All the regenerated plantlets from the highly regenerable cell cultures exhibited normal phenotypes and no variations in ploidy level were observed by flow cytometry (FCM) analysis.

• 식물조직배양학회지
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• 제28권4호
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• pp.179-184
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• 2001

담배 정상주 (Nicotiana tabacum L. cv. BY-4), 약배양으로 유도시킨 반수체 (2n=2x=24), 콜히친 처리로 염색체를 배가한 식물체 (2n=4x=48)및 그 후대식물체 (F$_1$)를 각각 사용하여 배수성에 따른 공변세포 내 엽록체 수를 조사하였다. 공변세포 내 엽록체의 수는 정상주에서 반수체의 2배로 배수성과 밀접한 관계를 나타내었다. 또한, 반수체를 콜히친으로 배가시킨 식물체에서 공변세포 내 엽록체의 수는 반수체의 2배로 배수성이 회복됨에 따라 증가하였다. 이배체의 후대식물에서도 공변세포 내 엽록체의 수는 반수체의 2배로 나타났다. 엽령에 따른 공변세포 내 엽록체 수의 변동도 관찰되지 않았다. 이러한 결과는 기공의 공변세포 내에 분포하는 엽록체 수와 배수성 (2x와 4x)과는 밀접한 관계가 있음을 시사하는 것이다. 기내에서 생장한 식물체에서 공변세포 내 엽록체의 수는 pot 재배식물체와 비슷한 결과를 나타내었다. 따라서 잎의 공변세포 내 기공수는 배수성을 간단하게 판정하는데 이용할 수 있을 것으로 보인다.

• Fisheries and Aquatic Sciences
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• 제20권11호
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• pp.29.1-29.7
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• 2017

The objective of this study was to determine a simple and reliable ploidy identification protocol for the rainbow trout (RT), Oncorhynchus mykiss, in the field condition. To evaluate the ploidy level and compare different detection protocols, triploid RT and gynogenesis were induced by UV irradiation and/or heat shock. The hatching rate at day 30 was 85.2% and the survival rate at day 90 was 69.4% (fingerling). The sex ratio of female RT was 93.75% in the gynogenesis group, illustrating that the UV irradiation inactivated the sperm DNA. The hatching rate and survival rate were 82.0 and 74.7%, respectively, in the triploid-induced group. The triploid induction rate by heat shock procedure was 73.9%. Cytogenetic protocols for ploidy identification such as chromosome counting, erythrocyte nuclear size comparison, and analysis of nucleolar organizing regions (NORs) by silver staining were compared. Silver nitrate staining showed the greatest success rate (22/23 and 32/32 for the triploid-induced group and gynogenesis group, respectively), followed by erythrocyte nuclear size comparison (16/23 and 19/32 for the triploid-induced group and gynogenesis group, respectively) and, lastly, chromosome preparation (2/23 and 6/32 for the triploid-induced group and gynogenesis group, respectively) with the lowest success rate. Based on our findings, silver staining for RT ploidy identification is speculated to be highly applicable in a wide range of research conditions, due to its cost-effectiveness and simplicity compared to other numerous ploidy detection protocols.

• 환경생물
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• 제20권1호
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• pp.35-39
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• 2002

The significance of cell ploidy and repair ability for the radioprotective efficiency of cysteamine was studied in DNA repair - proficient and repair - deficient yeast cells irradiated $^{60}C0\;\gamma-rays.$ Results have been obtained for the cell survival of two groups of yeasts-diplont and haplont cells, both in haploid and diploid states. For diploid Saccharomyces cerevisiae yeast cells, the correlation between the radio-protective action of cysteamine and the cell repair capacity was demonstrated. Such a correlation was not clearly expressed for haploid yeast cells. In addition, evidence was obtained indicating that the degree of the radioprotective action was independent of the number of chromosome sets in haplont yeast Pichia guilliermondii cells and in some radiosensitive mutants defective in the diploid-specific recovery. It is concluded on this basis that the radioprotective action may involve the cellular recovery process, which may be mediated by a recombination-like mechanism, for which the diploid state is required. The results obtained clearly show that the radioprotective effect was dependent on DNA repair status and indicate that the mechanism of the radioprotective action may be realized on the level of primary radiation damage production as well as on the level of postradiation recovery from potentially lethal radiation damage.

• 식물분류학회지
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• 제48권4호
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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.

• Journal of Plant Biotechnology
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• 제3권1호
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• pp.33-38
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• 2001

Protoplasts isolated from inbred lines of Brassica oleracea L. var capitata (cabbage) and Brassica campestris L. ssp. pekinensis (Chinese cabbage) were fused by PEG-mediated method, and somatic hybrid cells were differentiated into plants. for the identification of somatic hybrid plants, ploidy level, plant morphology, and cytological analysis were performed. All of the regenerated plants derived from fused protoplasts were shown to be 2X-4X, or higher ploidy level, presumably due to somatic hybridization or chromosome doubling. The morphology of leaves, petioles, and flowers showed an intermediate phenotype between Chinese cabbage and cabbage. Chromosome numbers in these somatic hybrids ranged mostly from 33 to 38. According to Genomic in situ hybridization (GISH) pattern, signals from both fusion parents of B.campestris or B.oleracea were detected in different colors when chromosomes of putative somatic hybrids were observed.

• Plant Biotechnology Reports
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• 제5권2호
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• pp.187-195
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• 2011

The gesneriaceous perennial plant Titanotrichum oldhamii has beautiful foliage and attractive bright yellow flowers. However, breeding of T. oldhamii by conventional sexual hybridization may be difficult because sexual reproduction of this species is very rare. In the present study, plant regeneration systems via both direct and indirect formation of adventitious shoots from leaf explants were established as the first step toward breeding T. oldhamii by using biotechnological techniques. Adventitious shoots were formed efficiently on medium containing $0.1mg\;l^{-1}$ benzyladenine. Histological observation showed that shoot formation on this medium occurred directly from leaf epidermal cells without callus formation. On the other hand, leaf explants formed calluses on medium containing $0.1mg\;l^{-1}$ 2,4-dichlorophenoxyacetic acid. The calluses could be maintained by monthly subculturing to fresh medium of the same composition. When the calluses were transferred to plant growth regulator-free medium, they formed adventitious shoots. Directly and indirectly formed shoots rooted well on medium containing $0.1mg\;l^{-1}$ indole-3-butyric acid. Plantlets thus obtained were successfully acclimatized and grew vigorously in the greenhouse. Flow cytometry analysis indicated that no variation in the ploidy level was observed in plants regenerated via direct shoot formation, whereas chromosome doubling occurred in several plants regenerated via indirect shoot formation. Regenerated plants with the same ploidy level as the mother plants showed almost the same phenotype as the mother plants, whereas chromosome-doubled plants showed apparent morphological alterations: they had small and crispate flowers, and round and deep green leaves.

• 식물조직배양학회지
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• 제24권3호
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• pp.175-181
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• 1997

양배추 F$_1$ 종자 그린 챌린저 배축으로부터 분리된 원형질체로부터 재분화된 protoclone들에 대한 형태적 특성, 배수성, 동위효소, RAPD 분석으로 변이 양상을 살펴보았다. 형태적 특성은 초자, 엽형, 엽색, 엽결각, savoy, wave등을 조사한 결과 대부분이 형태적으로 원식물체와 같았으나 3개체는 잎의 결각이 뚜렷하고 1개체는 savoy와 wave가 심하게 나타났다. Flow cytometry system으로 종자에서 정상적으로 발아한 배축, 자엽과 잎의 배수성을 측정한 결과 배측과 자엽에서는 2배체와 4배체 세포가 혼합되어 있었으나 잎에서는 일정하게 정상적인 2배체로 측정되었다. 잎을 재료로 하여 125개체 protoclone들의 배수성을 본 결과 2배체 91개체(72.8%), 4배체 32개체(25.6%), 혼합배수체 2개체(1.6%)로 나타났다. 또한 4배체를 나타내는 R$_{0}$ protoclone 개체를 자가수분시켜 얻은 종자를 발아시켜 배축, 자엽과 잎의 배수성을 측정한 결과 잎에서 4배체, 배축과 자엽에서는 4배체, 8배체 세포가 혼합되어 있었다. PGM과 MDH 동위효소 분석 결과 R$_{0}$ 정상개체 그리고 변이를 나타낸 개체, 배수성이 다른 개체들간의 밴드양상은 같았으며 15종류의 random primer를 사용한 RAPD에서도 차이는 없었다.없었다.

• 식물조직배양학회지
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• 제25권5호
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• pp.315-318
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• 1998

약배양 유래 녹색꽃양배추의 유식물 순화율 및 배수성을 조사하였다. 7가지 공시 품종중 순화율에 있어 Marathon은 80.8∼100%, Landmark는 79.2∼100%, Mariner는 71.4∼79.2%로 나타나 평균 순화율은 83.6%∼86.1% 이였다. 소포자 배에서 생성된 식물체의 배수성은 공변세포내 엽연체수 측정으로도 가능했으며, 또한 배수성의 조기측정을 위해 I-KI용액을 사용하여 엽록체의 즉시염색 관찰이 가능했다. 관찰된 평균 엽녹체수는 반수체가 8.5, 2배체는 13.5, 그리고 4배체는 18.5개로 나타 났으며 이를 기초로 분류한 재분화개체의 배수성은 반수체 47.1∼51.3%, 2배체 47.9∼51.7%, 4배체 0.8∼l.2% 로서 반수체와 2배체가 각각 반씩이고 4배체가 극히 적게 분포하며 인위적인 염색체 배가 없이도 상당수의 자연 배가된 2배체를 얻을 수 있었다.

• Molecules and Cells
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• 제25권2호
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• pp.163-171
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• 2008

The genus Cynodon comprises ten species. The objective of this study was to evaluate the genetic diversity of Korean bermudagrasses at the morphological, cytological and molecular levels. Morphological parameters, the nuclear DNA content and ploidy levels were observed in 43 bermudagrass ecotypes. AFLP markers were evaluated to define the genetic diversity, and chromosome counts were made to confirm the inferred cytotypes. Nuclear DNA contents were in the ranges 1.42-1.56, 1.94-2.19, 2.54, and 2.77-2.85 pg/2C for the triploid, tetraploid, pentaploid, and hexaploid accessions, respectively. The inferred cytotypes were triploid (2n = 3x = 27), tetraploid (2n = 4x = 36), pentaploid (2n = 5x = 45), and hexaploid (2n = 6x = 54), but the majority of the collections were tetraploid (81%). Mitotic chromosome counts verified the corresponding ploidy levels. The fast growing fine-textured ecotypes had lower ploidy levels, while the pentaploids and hexaploids were coarse types. The genetic similarity ranged from 0.42 to 0.94 with an average of 0.64. UPGMA cluster analysis and principle coordinate analysis separated the ecotypes into 6 distinct groups. The genetic similarity suggests natural hybridization between the different cytotypes, which could be useful resources for future breeding and genetic studies.