• Korean Journal of Fisheries and Aquatic Sciences
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• v.56 no.4
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• pp.549-557
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• 2023

This study aimed to investigate taxonomic differences in the early life history characteristics of Rhodeus ocellatus and Rhodeus notatus through an interspecific hybridization experiment. The hatching rates of the cross-bred eggs were 50% for the ON cross (R. ocellatus ♀×R. notatus♂) and 67% for the NO cross (R. notatus♀×R. ocellatus♂). Interestingly, the hatching time of the hybrids was longer than that of their parents. The newly hatched larvae exhibited distinct differences in their physical characteristics. The head of the adult fish protruded forward more than that of the ON cross. The pterygoid process was 45° for the ON cross and 90° for the NO cross. Furthermore, the tail shape of the ON and NO crosses closely resembled that of R. notatus.

• Korean Journal of Plant Taxonomy
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• v.52 no.1
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• pp.35-44
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• 2022

Clematis pseudotubulosa (Ranunculaceae), a new species from Gyeonggi-do in the Republic of Korea, is described and illustrated. The new species is morphologically similar to C. takedana but differs in its leaves, which are always ternate with shallowly lobed leaflets (vs. 1-pinnate with deeply lobed three to five leaflets), and its oblong-shaped flower buds (vs. ovoid), larger flowers (vs. smaller flowers), and pantoporate pollen (vs. tricolpate). A detailed species description, geographical distribution, and an identification key for all species of Clematis that occur in Korea are also provided.

• Korean Journal of Agricultural Science
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• v.41 no.2
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• pp.101-106
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• 2014

This study was conducted to identify lily species native to Korea from formosan lily (Lilium formosanum) belonging to Longiflorum section. Due to flowering time, flower color and orientation, long shelf life and resistant to diseases, the native lily species can be valuable genetic resources for interspecific hybrids. One of the chloroplast genes, matK, was used to clone and sequence to explore any base changes. The matK was successfully amplified into 1,539 bp (94% of the gene) and phylogenetic tree demonstrated 6 clades for those 11 lily species used in this study. There were one or two base substitutions among 10 lilies native to Korea, while formosan lily native to Taiwan exhibited 6 base substitutions in matK gene, rendering it genetically distant. A restriction enzyme NruI recognized one of the six base changes, and digested the matK gene of 10 native lily species only, but not in formosan lily. The confirmed cleavage characteristic of the target region in matK gene was designed into a CAPS (cleaved amplified polymorphic sequences) marker which will be available to estimate compatibility of interspecific hybridization and to trace the pedigree when those native lilies are crossed with the formosan lily.

• Journal of Korean Society of Forest Science
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• v.87 no.2
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• pp.194-200
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• 1998

The difference in leaf bud flushing times of Quercus species and their hybrids was compared among the trees from natural forest, seedlings from natural pollination and artificial crossing. In the natural forest of the Hiruzen experimental forest of Tottori University, Japan, Quercus species flushed in the order of Q. crispula > Q. anguste-lepidota > Q. takatorensis ${\fallingdotseq}$ Q. serrate > Q. dentata. The flushing time of seedlings from natural pollination was in the order of Q. aliena ${\fallingdotseq}$ Q. crispula > Q. angustelepidota > Q. takatorensis ${\fallingdotseq}$ Q. serrate > Q. dentata. The flushing times of $F_1$ hybrids by artificial crossing were between those of parental species. From the result of interspecific hybridization, it is shown that the earliness of flushing in Quercus species is a genetic character considered hereditable to progenies.

• Research in Plant Disease
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• v.11 no.2
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• pp.106-114
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• 2005

To breed powdery mildew resistant varieties, 104 accessions of Cucurbita spp. germplasm were evaluated. Powdery mildew resistance and horticultural characteristics of the accessions were investigated in the field conditions. C. martinezii was selected for high resistance to powdery mildew in the field. The growth of powdery mildew pathogen and response of leaf surface tissue to the pathogen were observed after artificial inoculation to resistant C martinezii and susceptible C. moschata cv. 'Wonye No.402'. Mycelium growth was very clearly different between resistant C. martinezii and susceptible C moschata cv. 'Wonye No. 402' at 5 days after inoculation at the adult stage. Interspecific hybridization was attempted to transfer powdery mildew resistance gene(s) from C. martinezii to C. moschata. A single dominant gene action was postulated as deter mining powdery mildew resistance at the seedling stage. But for the effective selection of powdery mildew resistant individuals, it was established that adult plant resistance should be confirmed in the field conditions after the seedling test. Through the seedling and field tests, C. moschata lines resistant to powdery mildew and superior to horticultural characteristics, were selected after 2 backcrossing and 3 selfing generations. The fruit characteristics of newly developed lines were similar to those of the recurrent parent, 'Jaechenjarae'.

• Journal of Practical Agriculture & Fisheries Research
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• v.22 no.1
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• pp.27-33
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• 2020

To date, various kiwifruit cultivars have been developed and released. Asexual propagation by grafting onto seedlings rootstock have been widely utilized commercially in fruit trees including kiwifruit (Actinidia spp.). Most of commercial kiwifruit cultivars belong to A. chinensis and A. deliciosa. Recently, several cultivars were developed by interspecific hybridization with different species including A. arguta. There is a possibility for graft-incompatibility due to interspecific hybridization and therefore, we investigated graft-compatibility of newly released yellow-fleshed kiwifruit cultivars and a hybrid cultivar with various rootstocks of different species. The yellow-fleshed cultivars grafted onto same species, A. chinensis 'Kuimi', showed good shoot elongation, about 1 m in length 50 days after grafting. In contrast, the shoot elongation of the yellow-fleshed kiwifruit grafted onto different species was retarded. The shoot length of a hybrid cultivar (A. arguta × A. deliciosa) 'Skinny Green' grafted onto four different species was about 1 m in length, showing good graft compatibility with other species. Nevertheless, long term studies for graft compatibility of hybrid cultivars are still needed since graft-incompatibility between different species can occur several years later.

• Journal of The Korean Society of Grassland and Forage Science
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• v.11 no.1
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• pp.1-5
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• 1991

Tall fescue(Festuca amndinacea Schreb.) is a productive pasture grass that is widely adapted to the soil and climate of Korea. It is regarded, however, as relatively low in palatability and nutritive value. On the other hand, Italian ryegrass(lo1ium rnultz$om Lam.) is highly nutritious and palatable, but is essentially weak in cold tolerance. Numerous investigators have succeeded in producing hybrids between Lolium spp. and Festuca spp. but no improved varieties have resulted. Therefore, intergeneric hybridization of Italian ryegrass with tall fescue is employed in 1984 to improve the adaptive and cold resistance quality of Italian ryegrass. In the mean time, F1-hybrid plants obtained by crossing Italian ryegrass x tall fescue were observed in open field. The results are summarized as follows: 1. Leaf-size and silica cell hair were intermediate between the types of parents but the shape of auricle tended to show Italian ryegrass and auricle-cilia to show tall fescue. 2. Roots of $F_1$-hybrid plants were mainly distributed at top soil and did not produced florescence material. 3. Head type of hybrids was intermediate between the types of parents but ray length was somewhat less than the length of tall fescue ray. Typical Italian ryegrass or tall fescue-like phenotypes were not observed. 4. Anthers of $F_1$-hybrid plants were formed but pollen were not formed. Even though pollen were formed, they were all empty. 5. Hybrid plants were more winterhardy and summer persistency than Italian ryegrass. They showed a equivalent growth to Italian ryegrass in spring and to tall fescue in summer. 6. Chromosome of $F_1$-hybrids was allopolyploid(2n=4~=28) and all $F_1$-hybrid plants were sterile.

• Korean Journal of Plant Taxonomy
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• v.41 no.4
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• pp.324-328
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• 2011

The purpose of this study was to analyze the interspecific relationships of Chenopodium album and its related taxa collected in Korea. The 18S-26S ribosomal DNA (45S rDNA) loci were detected directly on mitotic chromosomes by fluorescence in situ hybridization (FISH) and the chromosome numbers were examined using aceto-orcein methods. The chromosomal numbers of Chenopodium album var. album and C. album var. centrorubrum were 2n = 6x = 54, whereas for C. album var. stenophyllum, this number was 2n = 4x = 36. The basic chromosome number was x = 9. The biotin labeled 18S-26S rDNA probe exhibited eight yellow fluorescent signals on the metaphase chromosome of C. album var. album and var. centrorubrum respectively, while two yellow signals of C. album var. stenophyllum were noted. All of the signals on the chromosomes were located at the terminal regions. The chromosome number and FISH findings suggest that C. album var. centrorubrum is merged into var. album and that it is clearly distinguished from C. album var. stenophyllum.

• The Korean Journal of Mycology
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• v.22 no.4
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• pp.378-385
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• 1994

Interspecific somatic hybrids were obtained by protoplast fusion between Pleurotus ostreatus and Pleurotus sajor-caju. The fusion products between incompatible strains did not form clamp connections. Fruiting body of the clampless fusants was induced by light-dark cycle on saw-dust-rice bran substrate in glass bottles. Out of them, seven somatic hybrids produced fruiting bodies of intermediate morphology of the two species. Light and low temperature were the initiating factors for the development of clamped hyphae from the clampless mycelial colonies. All of these basidiocarps had clamp connections. Eight fusants from the six crosses were analysed with the segregation of genetic characters by random spore isolates. In the three combinations, unexpected alleles were shown. Somatic hybrid between P188 (P. ostreatus 2-1 + P. sajor-caju 2-53) and P. florida 2-3 by triple cross produced fruiting bodies similar to those of fusant between P. ostreatus and P. florida. All the genetic charaters from the three strains were shown to segregate and recombine.

• Korean Journal of Ichthyology
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• v.33 no.3
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• pp.157-166
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• 2021

Three specimens, presumed to be natural hybrids between Rhodeus notatus and R. ocellatus, were collected from Onyangcheon Stream area, Jwabu-dong, Asan-si, Chungcheongnamdo, the Republic of Korea, and morphological and phylogenetic analyses were performed to clearly identify their parent species. The body color of the three natural hybrids was light greenish-brown on dorsal side, and the size of red area on the upper front of the dorsal fin and the outer margin of the anal fin generally showed intermediate characters between the parent species, R. notatus and R. ocellatus. Among the measurement and meristic characters, the ratio of prepectoral length and preanal length in the standard length, and the ratio of snout length, interorbital width, length of caudal peduncle and depth of caudal peduncle in the head length, and the number of longitudinal row scales were analyzed as the unique characters of natural hybrids. In the rag1 gene of nuclear DNA, the three natural hybrids were analyzed to be reflected all the single nucleotide polymorphism sites between R. notatus and R. ocellatus, and in the phylogenetic tree using the cytb gene of mitochondrial DNA, they formed the same genetic clade as R. notatus. Therefore, three specimens, presumed to be natural hybrids analyzed in this study were identified as interspecific hybrids between female R. notatus and male R. ocellatus.