• Korean Journal of Ichthyology
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• v.22 no.4
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• pp.225-229
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• 2010

A intergeneric hybrid between Rhodeus uyekii and Acheilognathus signifer was collected in the Jojongcheon Bukhan River. The hybrid showed intermediate characteristics of two parental types in some key characters, such as color pattern of body, pigmentation of dorsal, anal, and caudal fins, and body spot and stripe. In addition, the hybrid had a fairly large number of lateral line scales, while it lacked a barbel, which is known as a key intergeneric character. The probable occurrence of a natural hybrid is supported by a viable $F_1$ hybrid produced with the parental species.

• Korean Journal of Ichthyology
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• v.26 no.3
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• pp.153-158
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• 2014

A natural intergeneric hybrid between Rhodeus pseudosericeus and Acheilognathus signifer was collected in their sympatric area, the Jucheongang (stream), the Namhangang (river), Korea. Morphological characters as well as mitochondrial cytochrome b (mt-cyb) gene were investigated to confirm the natural hybrid origin. In the comparison of morphological characters, the natural hybrid appeared to have intermediate characters between two parental species in several key characters such as the band of dorsal fins, the color pattern of body, and the body spot and stripe. Also, the collected specimen had an incomplete lateral line with a large number of pored scales. In analysis of mt-cyb gene, it revealed that the maternal species of the natural hybrid appeared to be R. pseudosericeus due to their 100% sequence identity. Thus, such results gave convincing evidence for the occurrence of a natural intergeneric hybrid between Rhodeus pseudosericeus and Acheilognathus signifer.

• Korean Journal of Ichthyology
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• v.3 no.1
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• pp.42-47
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• 1991

A suspected intergeneric hybrid cross between Pungtungia herzi and Pseudopungtungia nigra was collected at the Ungcheon River. Overall hybrid index did not show the hybrid connection clearly, but the most striking key character between two genus, pigmentation on the all fins except pectoral, the shape and position of the mouth part appeared to show the intermediary. So this specimen was thought to be an intergeneric natural hybrid which merits further study.

• Fisheries and Aquatic Sciences
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• v.18 no.1
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• pp.99-107
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• 2015

A natural hybrid of a probable intergeneric mating between the striped shiner Pungtungia herzi and the stone morocco Pseudorasbora parva (Cypriniformes: Cyprinidae) was captured in the Geumho River, a tributary of the Nakdong River basin in Korea. Morphological characters and DNA sequences were analyzed to verify its hybrid state and identify the parentage of its parent species. The hybrid exhibited a phenotypic intermediacy between the two parent species in the number of vertebrae and the mouth shape. Out of 1,488 base pair (bp) positions of the nuclear recombination activating gene 1 gene (rag1), which has a biparental mode of inheritance, 41-bp substitutions were detected between the two parent species, whereas an electropherogram of the hybrid displayed polymorphic double peaks at all of the base positions, along with one additional one, strongly indicating its hybrid state. Meanwhile, sequence comparison of the mitochondrial cytochrome b gene (mt-cyb) (1,140 bp), which has a maternal mode of inheritance, showed only 5-22-bp differences (97.6-99.5% identities) between the hybrid and Pu. herzi, but as many as 158-168-bp differences (85.2-86.1% identities) between the hybrid and Ps. parva, clearly indicating Pu. herzi as the maternal species. Thus, combined analyses of independent data sets (i.e., morphology and nuclear and mitochondrial DNA sequences) offered convincing evidence for the hybrid state of a naturally occurring hybrid resulting from intergeneric mating between a female Pu. herzi and a male Ps. parva.

• Korean Journal of Ichthyology
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• v.33 no.2
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• pp.45-56
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• 2021

A male, presumed to be an intergeneric hybrid between Tanakia lanceolata and Rhodeus pseudosericeus, was collected in the Boryeong Daecheoncheon Stream flowing into the Yellow Sea in the Republic of Korea. Morphological and molecular phylogenetic analyses were performed to discriminate the definite origin of the estimated natural hybrid. As a result of the morphological analysis, the color of the dorsal and anal fin rays edges of the natural hybrid individual, the upper and lower body colors followed the morphological characteristics of T. lanceolata, and that blue longitudinal stripe in the center of the caudal peduncle, the incomplete lateral line, and the barbels absent followed the morphological characteristics of R. pseudosericeus. In addition, as a result of the cytochrome b (cytb) gene analysis of mitochondrial DNA (mtDNA), the natural hybrid showed a nucleotide sequence similarity of 99.82 to 100% with T. lanceolata, and the maternal species was identified as T. lanceolata. As a result of the recombination activating gene 1 (rag1) gene analysis of nuclear DNA (nDNA), the natural hybrid showed double peaks pattern reflecting both the single nucleotide polymorphism sites (38 bp) between T. lanceolata and R. pseudosericeus, and the paternal species was identified as R. pseudosericeus. Therefore, a natural hybrid estimated male of Acheilognathinae analyzed in this study was found to be an intergeneric hybrid between a female T. lanceolata and a male R. pseudosericeus.

• Horticultural Science & Technology
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• v.33 no.1
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• pp.83-92
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• 2015

xBrassicoraphanus line BB#5, a new synthetic intergeneric hybrid between Brassica rapa L. ssp. pekinensis and Raphanus sativus L. var. rafiphera induced by N-methyl-N-nitroso-urethane mutagenesis in microspore culture, shows high seed fertility and morphological uniformity. Dual-color fluorescence in situ hybridization (FISH) using 5S and 45S rDNA probes and genomic in situ hybridization (GISH) using B. rapa genomic DNA probe were carried out to analyze the chromosome composition and the meiosis pairing pattern compared to its parental lines. The somatic chromosome complement is 2n = 38, which consists of 17 metacentric and two submetacentric chromosomes with lengths of 2.18 to $5.01{\mu}m$. FISH karyotype analysis showed five and eight pairs of 5S and 45S rDNA loci. GISH meiosis pairing analysis showed that 19 complete bivalents were most frequent and accounted for 42% of the 100 pollen mother cells examined. Based on chromosome number, size, morphology, rDNA distribution, and meiosis pairing pattern, both parental genomes of B. rapa and R. sativus appear to exist in xBrassicoraphanus line BB#5, demonstrating its genome integrity. Such stable chromosome constitutions and meiotic pairing patterns in somatic and meiotic cells are very rare in natural and synthetic intergeneric hybrids. Chromosomal studies and genetic and phenotypic changes in allopolyploids a re discussed. The results p resented h erein will b e usef ul f or f urther g enomic s tudy o f xBrassicoraphanus lines and their improvement as promising new breeding varieties.

• Korean Journal of Plant Tissue Culture
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• v.22 no.5
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• pp.261-266
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• 1995

This study was carried out to develop new varieties which are dwarf and tolerant to winter cold in the Aurantioideae by intergeneric crossing. to do that, the reciprocal crosses of Hwanggeumyooza and trifoliate orange, yooza and trifoliate orange were done and in vitro immature ovule culture of their hybrid was carried out .The callus formation from immature ovule was good in order of Hwanggeumyooza, Hwanggeumyooza $\times$ tifoliate orange, yooza, and trifoliate orange and best at 1 to 3 mg/L NAA+0.5mg/L zeatin on MT medium. In vitro germination percentage of 20week old hybrid of Hwanggeumyooza $\times$ tifoliate orange and trifoliate orange $\times$ Hwanggeumyooza were 41.3% and 37.7, respectively. The phenotype of hybrid (95%) of Hwanggeumyooza $\times$ trifoliate orange and that (100%) of trifoliate orange $\times$ Hwanggeumyooza were similar to that of trifoliate orange. After Hwanggeumyooza was pollinated by pollens of trifoliate orange, the pollen tubes grew on stigma after 3h of pollination and entered into micropyle after about 24~28 h. One gamete in pollen was fused with polar nuclei after 2 days and other one fused with egg nucleus at 3days after pollination. The fruit set percentage by intergeneric crossing was 14.0% in Hwanggeumyooza $\times$ trtfoliate orange and 17.5% in trifoliate orange $\times$ Hwanggeumyooza. The fruit set percentages of Hwanggeumyooza. and trifoliate orange were 34.2% and 39.5% by artificial self-fertilization, 34.2% and 39.5% by artificial cross fertilization, 3.1% and 1.4% by parthenocarpy and 13.0% and 3.0% by natural fertilization, respectively. The somatic and gametic chromosome numbers of Hwanggeumyooza, yooza, and trifoliate orange were 2n=18 and n=9.

• The Korean Journal of Mycology
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• v.27 no.6 s.93
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• pp.399-405
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• 1999

Intergeneric hybrids between Saccharomyccopsis fiburigera KCTC 7393 and Saccharomyces cerevisiae KCTC 7049 (tyr-, ura-) were obtained by nuclear transfer technique. Nuclei isolated from the wild type S. fiburigera strain were transfered into auxotrophic S. cerevisiae mutants and new strains showing an increased starch degrading capability were selected. Maximum production of protoplasts was obtained from the treatment with 0.1 % Novozym 234 at $30^{\circ}C$ for 90 min, and most effective osmotic stabilizer for the isolation of protoplasts was 0.6 M KCl at pH 5.8. The frequency of protoplast regeneration was 14.64% under the conditions. Genectic stability, conidial size, DNA content, and nuclear stain suggested that the fusants were aneuploidy. The specific activity of ${\alpha}-amylase$ was observed to increase about $1.2{\sim}1.9$ folds.

• 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.

• Microbiology and Biotechnology Letters
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• v.24 no.1
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• pp.50-58
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• 1996

Interspecific hybrids between Aspergillus oryzae var oryzae and A. nidulans 514 were obtained by nuclear transfer technique. Several autotrophic mutants isolated from conidiospores of the two strains were mutagenized with ultraviolet and N-methyl-N-nitrosoguanidine. Optimal conditions for formation of intergeneric hybrids were investigated. Frequencies of hybrid formation by nuclear transfer were $3{\times}10^{-5}{\sim}1{\times}10^{-5}$. From observation of genetic stability, conidial size, DNA content, and nuclear stain, it was suggested that their karyptypes are aneuploid. The hybrids showed 1.1~1.4 fold higher xylanase activities than parental strains did. The xylanase of Aspergiilus sp. TAVD514-3 was purified and some of it's enzymatc characteristics were investigated. The enzyme was purified about 85 fold with an overall yield of 17% from the culture medium by ammonium sulfate fractionation, Sephadex G-75 gel permeation chromatography, and CM-sephadex A-50 ion exchange chromatography. The purified enzyme functions optimally at pH 9.0 and 80$^{\circ}C$. The enzymatic activity was increased by the presence of $Mg^{2+}$ and $Mn^2$ ions.