• Horticultural Science & Technology
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• v.34 no.5
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• pp.771-778
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• 2016

Seedless grape (Vitis spp.) cultivars with large berries can be developed from hypo- and hypertetraploid seedlings. The low occurrence of hypo- and hypertetraploid seedlings, however, has impeded the breeding of new hypo- and hypertetraploid grape varieties. In order to establish hypoand hypertetraploid seedlings, we examined the chromosome numbers in seedlings of self-, open-, and cross-pollinated hypotetraploid 'Takao' and hypertetraploid 'RB9127K' grape. Three of the five seedlings (60%) from 'Takao' were aneuploid, including one with 74 chromosomes (2n=4x-2) and two with 75 chromosomes (2n=4x-1). In 'RB9127K', 26 of the 193 seedlings (13.5%) were aneuploid, including three seedlings with 75 chromosomes (2n=4x-1), 18 with 77 chromosomes (2n=4x+1), and five with 78 chromosomes (2n=4x+2). The high frequency of aneuploids from 'Takao' and 'RB9127K' grape indicates that meiosis in hypo- and hypertetraploid female parents is prone to segregation error. These results suggest that various hypo- or hypertetraploid seedlings can be successfully produced using hypo- or hypertetraploid grapes as female parents, which can contribute to the development of new seedless grape varieties with large berries.

• Korean Journal of Medicinal Crop Science
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• v.12 no.5
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• pp.397-400
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• 2004

The chromosome numbers and karyotypes were investigated in four Korean native species of the genus Hosta. The chromosome complements were diploid of 2n=60 in H. japonica var. lancifolia Nakai and H. capitata Nakai, aneuploid of 2n=59 in H. minor (Bak.) Nakai, and modified triploid of 2n=92 in H. longipes (Fr. et Sav.) Matsumura. All the species carried four sets of distinctly large chromosomes of which the chromosome types were telocentrics or subtelocentrics with $4.4{\sim}7.2\;{\mu}m$ in length. The other chromosomes were meta-, submeta, subtelo-, or telocentric types and showed gradual length degradation in the range of $1.0{\sim}3.0\;{\mu}m$. The satellites appeared vestigially in a pair or a triplet set of chromosomes which depends on the species. New chromosome number and karyotype in H. longipes were the first report in this species. The structural rearrangement was suggested to explain the modified triploid composition of 2n=92.

• Journal of Korea Foresty Energy
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• v.19 no.1
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• pp.38-48
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• 2000

This study was initiated to investigate similarity and intraspecific variation in pollen morphology of korean subgenus. lepidobalanus Endl, of the genus Quercus L. The parameters measured were polar axis length (PL), equatorial width (EW), colpus length (CL) and copus width (CW), and PE (PL/EW) retios were calculated. The cluster analysis based on these variables of this result showed that the similarity between Q. acutissima Carruther and Q. variabilis Blume was the highest. Wide variation in the pollen grain size of Quercus dentata Thunb. ex Murray might imply, the existence of polyploid and/or aneuploid forms. Studies of ploidy levels within species are recommended for Lepidobalanus species.

• Proceedings of the Korean Society of Crop Science Conference
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• 2000.04a
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• pp.120-121
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• 2000

• Microbiology and Biotechnology Letters
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• v.26 no.4
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• pp.290-296
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• 1998

Interspecific hybrids between Aspergillus oryzae var. oryzae and Penicillium chrysogenum (Tyr$\^$-/), high alkaline protease producing fungi, were obtained by nuclear transfer technique. Nuclei isolated from the wild type Aspergillus oryzae var. oryzae strain were transferred into auxotrophic Penicillium chrysogenum mutants and selected the new strains showing an increased protein degrading capability. Maximum production of protoplasts were obtained by 1% Novozym 234 at $30^{\circ}C$ for 3 hours and the most effective osmotic stabilizers for the isolation of protoplasts were 0.6M KCl. Frequencies of hybrid formation by nuclear transfer were 1.3${\times}$10$\^$-3/∼2.8${\times}$10$\^$-3/. They could be suggested as an aneuploid by the observation of genetic stability, conidial size, DNA content, and nuclear strain. The hybrids showed 1.1～2.2 fold higher alkaline pretense activities than parental strains.

• Korean Journal of Microbiology
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• v.33 no.1
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• pp.31-37
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• 1997

Intergeneric hybrids between Aspergillus niger and Perricillium ch~y.sop~um(Tyr ), hyperlipolytic enzyne-producing fungi, were obtained by nuclear transfer technique:. Optimal conditions for formation of intergeneric hybrids were investigated. Maximum production of protoplasts were obtainrd by 1% Novozym 234 at $30^{\circ}C$ for 3 hrs and the most effective osmotic stabilizers for the isolation of protoplasts were 0.6 M KC]. Frequencies of hybrid formation by nuclear transfer were $1.3{\times}$10^{-3}$$ $-3.8{\times}$10^{-3}$$. From the chervation of genetic stability, conidial size, DNA content, ;md nuclear stain, it was suggested that their karyotypes are aneuploid. The hybrids showed 1.4-2.2 fold higher lipase activities than parental strains. It was strongly supported by results of this study that nuclear transfer technique is much more efficient in the formation of intergeneric hybrids than protoplast fusion and is very useful for the improvement of strains.

• Korean Journal of Microbiology
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• v.24 no.3
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• pp.221-227
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• 1986

The strain of Aspergillus nidulans carring a uvsH mutation which had been shown to be absolutely required for UV or 4-NQO induced mutagenic processes was studied on mitotic recombinational behaviour. Although the effect of uvsH locus on spontaneous mitotic crossing over between fpB37 and centromere was not considerable, UV-induced intergenic recombination did not occur in uvsH/uvsH homozygotic diploid. In case of gene conversion at riboflavin locus between a pair of non-complementary alleles, riboA1 and riboA3, the uvsH mutation was not concerned with that process occurred spontaneously or induced by UV irradiation. When the cells were irradiated by UV light, high degrees of aneuploid productions were detected in diploid homozygous for uvsH as compared with wild type, while much difference was not found during normal growth.

• Journal of Chest Surgery
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• v.50 no.3
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• pp.228-228
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• 2017

• Journal of Plant Biology
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• v.33 no.4
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• pp.237-242
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• 1990

Geographical distribution of diploid plant with AA genome (2n=16) and allotetraploid with AABB genome (2n=34) of Scilla scilloides Complex from Korea has been studied. The composition and frequencies of B chromosomes ere also investigated. Plants with AABB genome were predominant over AA genome plants. A mixed population of AA and AABB genome plants was found for the first time. Aneuploid plants have not been found. Chromosomes of AA genome were composed of three pairs of metacentric, two pairs of submetacentric, two pairs of subtlocentric and one pair of telocentric chromosomes, whereas BB genome was four pairs of metacentric and five pairs of subtelocentric chromosomes. B chromosomes were classified into two categories, isochromosome (F) and chromosome fragment (f). The frequencies of B chromosomes were 43% in AA genome plants and 44% in AABB genome plants. The number of B chromosome ranged from 1 to 3 and 1 to 7 in AA and AABB genome plants, respectively. B chromosome combinations were F and F+f in AA genome plants and F, F+f and f in AABB genome plants.

• Journal of Plant Biology
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• v.15 no.1
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• pp.28-32
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• 1972

Young haploid leaf derived from the anthers of tobacco plant was cultuerd and plantlets of various ploidies were obtained. When the leaf was put on the medium supplemented with kinetin as growth regulator, plantlets developed directly from the leaf, and the plants coming out in early stage of culture were all haploid. Plants developing in later stage were mostly haploids with some exception of diploid and aneuploid. Leaves were also cultured on the callus-inducing media supplemented with 2,4-D and kinetiion, and the calluses were sub-cultured for six months. Plants developed from these calluses were mostly aneuploids of various chromosome numbers. In view of the fact that the plants directly developed from the leaf were all haploid, the tissue of the original leaf explant was assumed to be uniform as far as chromosome number was concerned. On the other hand, it seemed that the occurrence of various ploidies in the plants derived from the calluses of same origin was the result of the influence of in vitro culture. Apical meristem tissues and various multicellular bodies were formed in the epidermal and inner mesophyll tissues as well as in the sub-epidermal cells.