• Korean Journal of Medicinal Crop Science
• /
• v.16 no.1
• /
• pp.39-43
• /
• 2008

The effect of colchicine treatment on the agronomic performance and polyploid formation of Bupleurum falcatum using flow cytometry technique was investigated. The roots of 4-leaf stage plants were treated with colchicine (0.5%) for 3, 6, 12, and 24 hours and then transplanted in the field. Agronomic characters (survival rate, plant height, chlorophyll content, bolting rate) were recorded at 4 weeks and 6 months after transplanting while flow cytometry technique was conducted for determination of polyploid formation. Flow cytometry technique revealed polyploid nuclear DNA formation in colchicine treated plants. The highest number of polyploids was obtained at the shortest colchicine treatment time indicating an inverse relationship between colchicine treatment time and polyploid formation. Results also showed that survival and bolting rates were inversely related with the treatment time while plant height and chlorophyll were not significantly affected by the treatment. This study showed a convenient method for determination of colchicine-induced polyploid in B. falcatum and its superior agronomic performance at shorter treatment time.

• ALGAE
• /
• v.19 no.2
• /
• pp.79-90
• /
• 2004

Nuclear DNA contents of spermatia from eight ceramiacean and four dasyacean algae (Ceramiales, Rhodophyta) and microspores from two land plants were estimated by fluorescence microscopic image processing and their nuclear SSU rDNA sequence data were analyzed. In frequency distribution patterns, the DAPI-stained nuclear volume (NV) of spermatia showed two peaks corresponding to 1C and 2C. Nuclear 2C DNA contents estimated from NV were 0.45-2.31 pg in ceramiacean and 0.40-0.57 pg in dasyacean algae and 8.42-9.51 pg in two land plants, Capsicum annuum and Nicotiana tabacum. By nuclear patterning of vegetative cells derived from an apical cell, 2C DNA contents of spermatia were 2.31 pg in an alga having uninucleate and non-polyploid nucleus (Aglaothamnion callophyllidicola), 0.45-1.94 pg in algae having uninucleate and polyploid nucleus (Antithamnion spp. and Pterothamnion yezoense), and 0.40-0.62 pg in algae having multinucleate and non-polyploid nuclei (Griffithsia japonica and dasyacean algae). Each mature spermatium and microspore (pollen grain) seemed to have a 2C nucleus, which may provide a genetic buffering system to protect the genetic content of a spermatium and microspore from potentially lethal mutations. Nuclear DNA content and SSU rDNA sequence of Antithamnion sparsum from Korea were reasonably different from those of Antithamnion densum from France. The data did not support the previous taxonomic studies that these two taxa could be conspecific.

• Korean Journal of Plant Taxonomy
• /
• v.52 no.4
• /
• pp.219-225
• /
• 2022

To elucidate the ancestry of the allopolyploids E. stevenii and E. boöphthona, I examined eleven isozyme loci and 24 morphological characters from 28 populations representing five related Euphorbia species from Australia. According to an analysis of genetic and morphological data, three diploid species differentiated recently, but two independent polyploid species are estimated to have differentiated a relatively long time ago. Fixed heterozygosity for most isozymes in E. stevenii and E. boöphthona strongly suggests that these two species are allopolyploids rather than autopolyploids. The isozyme profiles of E. stevenii indicate that it is an allopolyploid that evolved from interspecific hybridization between the diploid E. tannensis and unidentified or extinct tetraploid species. In addition, isozyme patterns strongly suggest that E. stevenii was one of the ancestors of E. boöphthona. However, E. boöphthona showed a large number of fixed alleles that were not detected in any other Australian Eremophyton species. The most likely hypothesis for the origin of E. boöphthona is that it was formed by hybridization and chromosomal doubling between an extinct diploid species and the hexaploid E. stevenii.

• Proceedings of the Zoological Society Korea Conference
• /
• 1998.10b
• /
• pp.272.2-272
• /
• 1998

No Abstract, See Full Text

• Proceedings of the Korean Society of Plant Biotechnology Conference
• /
• 2006.06a
• /
• pp.21.2-22
• /
• 2006

• Journal of Plant Biology
• /
• v.37 no.1
• /
• pp.69-76
• /
• 1994

The present work was conducted to examine the effect of tobacco smoke solution, and its components such as nicotine and catechol treated separately on the root tip cells of Allium cepa L The mitotic abnormalities in root tip cells treated with those three components were increased linearly, while the mitotic index was decreased following concentrations of the components. Chromosomal abnormalities showed 29.7%, 15.8% and 13.0% in the treatment of tobacco smoke solution, nicotine, and catechol, respectively. The abonormalities were included polyploid, c-mitosis, stickness at metaphase, laggard, bridge formation at anaphase or telophase, and micronucleus, abnormal nucleus at interphase, after the treatment of the components for 24 hours. hours.

• Korean Journal of Microbiology
• /
• v.28 no.3
• /
• pp.181-187
• /
• 1990

STA gene coding glucoamylase was introduced into haploid Saccharomyces cerevisiae SHY3 and polyploid Saccharomyces cerevisiae 54. We constructed the recombinant plasmid by substituting the promoter region of alcohol dehydrogenase isoenzyme I gene for that of STA gene to increase the expression of STA gene and found that the activity of glucoamylase was increased in transformants. The plasmid stability was improved remarkably when we got the STA gene into the plasmid which had centromere. The activity of glucoamylase and transformation frequency of it, however, was decreased because of low copy number. Industrial polyploid strain was transformed with the recombinant plasmid having the $2\mu$ origin of replication and STA gene. It produced more alcohol than host when fermented in liquefied starch media. The industrial strain, however, was not transformed with the autonomously replicating plasmid containing centromere.

• Korean Journal of Microbiology
• /
• v.33 no.3
• /
• pp.199-202
• /
• 1997

The effect of electric shock (AC 38 Vll.3 cm) on the lethal effect and induction rate of mutation of chemical mutagen N-methyl-N'-nitro-N-nitrosoguanidine (NTG) was examined by using the spores of Streptomyces and the cells of haploid and polyploid yeast strains of Saccharomyccrs. Spores of Sireptomyces were all alive after 180 min of electric shock, hut all dead after 960 min-treatment. When the spores of Streptomyces or the cells of haploid and polyploid yeast were treated with electric shock and NTG, the electric shock increased the lethal effect of NTG; the survival rate of Streptomyces dropped from 72 to 48% after 180 min-treatment and those of haploidand polyploid-yeast decreased from 8 to 3% and 25 to lo%, respectively, after 40 min-treatment. The electric shock also increased mutation rates of Streptomyces and haploid yeast. from 1.8 to 13.6%' after 120 min-treatment and from 2.4 to 4.8% after 40 min-treatment, respectively.

• Korean Journal of Poultry Science
• /
• v.23 no.1
• /
• pp.1-7
• /
• 1996

In order to produce polyploid quail, the patterns of spermatogenesis and induction of diploid spermatozoa were analyzed by administration of spindle fiber inhibitor agent. Colcemid at the dose level of 37 $\mu\textrm{g}$ /100 g BW was Injected intraperitoneally to 50 Japanese quail males for 3 consecutive days. Five to 20 days after the first colcemid injection, the metaphase spreads from mitotic spermatogonia, primary spermatocyte and secondary spermatocyte were observed. By cytogenetic analysis, 9.4％ of spermatogonia and spermatocyte cells in germ cells from the treated males was found to be polyploid cells. As compared with colcemld treated, the males with non-treated colcemid had only 2.3％ polyploid cells in germ cells. The induction of diploid germ cells was highest in 10 days after the first colcemid injection and was lowest in 5 days after the first colcemid injection. These results suggested that between 10 to 15 days before maturation of the spermatozoa, the male germ cells were most sensitive to colcemid treatment. Spindle fiber inhibitor agent was also more sensitive to mitotic division of spermatogonia than meiotic division of primary and secondary spermatocyte.

• Journal of Sericultural and Entomological Science
• /
• v.43 no.1
• /
• pp.53-54
• /
• 2001

The chromosome number of Morus bombycis Koidz. and Morus monogolica C.K.Schn. growing wild in the Korea Peninsula is diploid (2n=28) and that of Morus tiliaefolia Makino is hecxaploid (2n=84). The somatic cell division of each species is nomal.