• The Korean Journal of Mycology
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• v.25 no.2 s.81
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• pp.143-151
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• 1997

Interspecific hybrids between Aspergillus niger and Penicillium notatum (Tyr-), hyperlipolytic enzyme-producing fungi, were obtained by nuclear transfer technique. Optimal conditions for formation of intergeneric hybrids were investigated. Maximum production of protoplasts was obtained by 1% Novozyme 234 at $30^{\circ}C$ for 3 hrs and the most effective osmotic stabilizers for the isolation of protoplasts were 0.6 M KCl. Frequencies of hybrid formation by nuclear transfer were $3.8{\times}10^{-3}{\sim}1.3{\times}10^{-3}$. From the observation of genetic stability, conidial size, DNA content, and nuclear stain, it was suggested that their karyotypes are aneuploid. The hybrids showed $1.2{\sim}1.7$ 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 Plant Taxonomy
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• v.42 no.3
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• pp.215-221
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• 2012

Five Korean Calanthe species, C. discolor, C. bicolor, C. sieboldii, C. reflexa, and C. aristulifera, were studied using amplified fragment length polymorphism (AFLP) to assess their taxonomic and genetic relationships. Sixteen accessions belonging to five native Calanthe spp. and mutants with yellow tepal and white lip (YW mutants) were studied. We identified 50 putative markers using AFLP analysis. The results of AMOVA showed that genetic variance was higher between species than within species. Genetic dissimilarity when compared with the rest of the species was the lowest for individuals of the YW mutants and the highest for individuals of C. reflexa. The mutants clustered outside the major group. Calanthe bicolor clustered with C. discolor, suggesting that its genetic composition is closer to that of C. discolor. Though it is suggested to have originated as a result of natural hybridization between C. sieboldii and C. discolor, introgression is likely to have occurred in the direction of C. discolor based on the data of molecular marker, clustering and genetic dissimilarity. Calanthe reflexa and C. aristulifera were genetically the most diverse of the species studied. In conclusion, the results showed that there is genetic diversity in Korean Calanthe species, that C. bicolor introgressed in the direction of C. discolor and that the YW mutants are genetically closer to C. sieboldii.

• Journal of Plant Biotechnology
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• v.44 no.1
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• pp.35-41
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• 2017

One of the most important species, Brassica rapa encompasses a variety of commercial vegetables, such as the Chinese cabbage, pak choi and oilseed crops. The LP08 of yellow sarson (Brassica rapa ssp, tricolaris) have a distinct morphology, with yellow seed color and a unique tetralocular ovary. LP21 of pak choi (Brassica rapa ssp, chinensis) have a dark brown seed color and bilocular ovary. In this study, we generated double haploid plants by crossing the LP08 (maternal variety) and LP21 (paternal variety), using microspore culture. A total of 66 accessions with various morphological characteristics were used for content analysis of flavonoids. The three flavonoids, quercetin, naringenin and kaempferol, showed differing contents in the two crossing parents. The Chinese cabbage type 'Chiifu' was used as the control. The highest accumulation of total flavonoids was observed in LP08. The lowest mean total flavonoids were found in 'Chiifu'. Among the 66 DH accessions, the quercetin contents of 18 accessions showed higher content than LP08. Kaempferol content was also high, and was found to be 79.7% of the total flavonoid content. Naringenin content was low at 2.8%, and was not detected in 22 accessions. Interestingly, the quercetin content positively correlated with the kaempferol content. These results can be used to identify genetic locus and genes related to useful traits. Phenotypic analysis of 66 DH accessions can further be used for natural selection of good breeding materials in B. rapa.

• The Korean Journal of Zoology
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• v.33 no.4
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• pp.499-508
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• 1990

Surveys of elecirophoretic variations in isozymes and proteins encoded by 25 persumtive loci were conducted to estimate the degree of genic variation and to assess species recognition for three species of the Family Gasterosteidae (Pisces) in Korea. The average degree of genic variation of Gasterosteus aculeatus was HD = 0.086, HG = 0.084, and P =36% and it was similar to Pungitius sinensis (HD = 0.080, HG = 0.091, P = 29%). But P.kaibarae was less variable than these species (HD = 0.034; HG = 0.034, P = 13%). The average genetic similarities among the populations in each species of Gasterosteus aculeatus pungitius sinensis and P. kaibarae were S = 0.963, S = 0.953 and S = 0.800 respectively.Yongchon and Kyongiu populations of P. kaibarae were genetically remote from the rest of the conspecific populations (S = 0.690). Chae (1988) also observed morphological differences between them. The value of genetic similariiy coefficients of S = 0.606 between P. sinensis and P. kaibarae is low enough to consider as specific level of genetic difference, but moderate rate of hybridization (44%) between them at a synpatric area of Kangnung indicates that isolating mechanism is incomplete. Therefore it is concluded that P. sinensis and P. kaffarae are semispecitic status. Intergeneric genetic similarities between the genus Gasrerosteus and Pungitius were S = 0.052 and this value is the lowest estimate up to date in freshwater fishes.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.20
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• pp.27-62
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• 1975

These studies were aimed at clarifying whether or not selecting agronomic characteristics of hybrid-rice populations under greenhouse conditions was useful. The selection of two quantitative characteristics, culm length and heading date, and two qualitative characteristics, shattering and awnedness, was very effective, but the flag leaf length and the exsertion of panicle was not consistent, varying from one cross to another.

• Korean Journal of Ichthyology
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• v.18 no.4
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• pp.339-346
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• 2006

In this study we conducted artificial hybridization between two sibling species, Rhodeus uyekii and R. notatus, and observed the morphological characteristics in early developmental stage. The two species showed difference in egg shape having rhombus and club respectively. The morphology of yolk of larva just hatched also showed well specific characteristics, that is the bean chaff type for R. uyekii (U type) and anchor type for R. notatus (N type). The rate of fertilization between female R. uyekii and male R. notatus (UN type) and between female R. notatus and male R. uyekii (NU type) were complete and its hatching rate were very high, 71.6% for UN type and 97.5% for NU type. The differences occurred in the yolk shape of hatched larvae for each combination of hybrids. In the group of UN, U type of larvae were found very rarely, but almost all the larvae showed intermediate shape polarized to NN type. Similar phenomenon was observed in the NU having intermediate polarized to UU, but without any NN type. These hybrids will be analyzed for their external morphology, sex ratio, the function of sexual organ and karyology after they grown up to adult.

• Korean Journal of Plant Tissue Culture
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• v.26 no.1
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• pp.31-35
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• 1999

Morphological characteristic during formation of tobacco crown gall tumor and genetic tumor, and their differential response to growth regulator were investigated in in vitro culture. Crown gall tumor was induced from tumor tissue transformed by infecting Agrobacterium tumefaciens C58. Genetic tumor was induced from tumor tissue which was induced spontaneously from reciprocal interspecific hybrids between Nicotiana glauca (2n=24) and Nicotiana langsdorffii (2n=18). Morphological characteristic of crown gall tumor, genetic tumor, and teratoma shoot was very similar, and they were actively proliferated on hormone-free medium. Typical tumor callus and teratoma shoot formed from crown gall tumor on the hormone-free medium. On the contrary, tumor callus derived from genetic tumor formed as a crown gall tumor callus on the medium supplemented with 0.5 mg/L of 2,4-D, and lots of teratoma shoots without any root formed on the hormone-free medium. Root development from the teratoma shoots was hardly obtained on the medium with IAA, GA and active carbon. However, teratoma shoots with roots, as normal shoots, were initiated occasionally on the hormone-free medium. These shoots also formed new genetic tumor on the stem, which leaves formed lots of teratoma shoot on the hormone-free medium in in vitro culture.

• Korean Journal of Poultry Science
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• v.30 no.1
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• pp.11-16
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• 2003

This study was conducted to investigate chemical and sensory characteristics of boiled soup extracted from crossbred ogol chicken as affected by the level of Flavourzyme produced from Aspergillus oryzae and composed with endo-proteinase(674U/g) and exoproteinase(8,053U/g). It was hydrolyzed by different concentrations of the protease enzyme (Flavourzyme)(0%(Control), 0.01％(T$_2$), 0.1%(T$_3$) and 0.5%(T$_4$)) at 45$^{\circ}C$ for 4hrs. Manufacture of the extract was performed by boiling treated meats with medicinal herbs(Sipchun daebo) at a higher pressure condition. Minerals, free amino acid content, sensory properties of the extract were as follows. The sodium contents were increased as the treatment levels of enzyme increased. The iron contents were lowest when the enzyme treated by 0.5% level, however there were not significantly different among the treatments. The copper and mangan contents had no significantly different among the enzyme treatment levels. Higher contents of fee amino acid were observed as the amount of the protease increased with the treatment of higher than 0.1％ enzyme, no significant effect was observed. In sensory properties, the extract manufactured by addition of 0.01∼0.1% of Flavourzyme resulted in a similar or better appearance, flavor, taste and overall palatabilitycompared to control(no enzyme treatment). However, the extract manufactured with 0.5% of Flavourzyme resulted in lower scores in appearance, flavor, taste and overall palatability than the control. In addition, this product showed more off-flavor than control.

• Horticultural Science & Technology
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• v.17 no.6
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• pp.742-746
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• 1999

Contents of mineral element and cytokinin in the xylem sap of 'Keumdongee' and 'Tongilhwang' oriental melons were compared with those in oriental melons grafted onto 8 rootstocks. The effect of grafting on the fruit quality of oriental melon was also investigated. Flesh firmness varied with rootstocks. Soluble solids contents in the placenta tissue of grafted 'Tongilhwang' were higher than that in the 'Keumdongee'. Electric conductivity of the xylem sap in own-rooted plants was higher in 'Keumdongee' than in 'Tongilhwang', but it increased in 'Tongilhwang' once they were grafted. The sap volume per plant was greater in 'Keumdongee' than in 'Tongilhwang'. The mineral concentrations varied considerably depending on the rootstock used. Xylem sap of grafted oriental melons contained a higher amount of mineral ions, especially $NO_3{^-}$ and $PO_4{^-}$, than did the sap in own-rooted plants. The increase in the mineral levels in sap due to grafting was most apparent in 'Tongilhwang'. Xylem sap from both 'Keumdongee' and 'Tongilhwang' contained trans-zeatin (t-Z), trans-zeatin riboside (t-ZR), and dihydrozeatin riboside (DHZR). Small amounts of isopentenyl adenine (IPA) and isopentenyl adenine riboside (IPAR) were also detected. Trans-zeatin riboside was the most abundant, followed by t-Z. Cytokinin concentration in 'Keumdongee' was not significantly influenced by rootstock type used, although the highest concentration of cytokinins in 'Keumdongee' was obtained with 'Chamtozwa' rootstock. However, the cytokinin concentration in 'Tongilhwang' increased with grafting irrespective of rootstock type used.

• Korean Journal of Plant Taxonomy
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• v.36 no.4
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• pp.263-277
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• 2006

Anemone pendulisepala, recently described as a new species, is distributed in sympatry with A. reflexa, A. amurensis, and A. raddeana at Mt. taebeark and Mt. Baekdu. Anemone pendulisepala was previously proposed to be a hybrid species between A. reflexa and A. amurensis becaue it displavs overlapping features with them in involucre shape, petiole length, sepal apex and xylem shape, To verify the taxonomic status and to examine the hybridity of A. pendulisepala, sequences of ITS region of nuclear ribosomal DNA and the psba-trnH, rps16 and trnLF region of cpDNA from 36 accessions of 5 taxa including outgroup were analyzed. In maximum parsimony tree based on ITS sequences, A. pendulisepala had the same sequences of A. reflexa and was clustered with monophyletic A. amurensis, and then A. raddeana. Anemone pendulisepala was distinguished from the other taxa by having four base insertion in rps16 region, two species-specific bases and insertion in trnLF region. In the phylogenetic trees of combined cpDNA, A. pendulisepala showed monophyly with the bootstrap 100%. Anemone pendulisepala exhibited no polymorphism and shared no sequences with putative parental or related taxa examined in this study. Molecular data suggest that A. pendulisepala should be a distinct species, and no evidence of the hybridization was detectcd.