• Korean Journal of Weed Science
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• v.9 no.2
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• pp.141-148
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• 1989

Echinochloa species collected from 13 places of Korea appeared to be morphologically very different. They were classified by Yabuno's seed morphology method into two species such as Echinochloa oryzicola and Echinochloa crus-galli which have two varieties such E. crus-galli var, cuss-galli and var, praticola. Among them, E. oryzicola was morphologically similar to Oryza sativa, but it had small leaf length with straight from, no awn, late heading and little interspecific variance. As compared with E. oryzicola, E. eras-galli var. crus-galli, and var, praticola showed a great variance exerting so difficulty in classifing them morphologically, particularly a great variance in leaf length, tiller number and grain size. E. oryzicola species showed the more sensitive response to butachor and thiobencarb herbicides than E. eras-galli var. praticola and var. eras-galli. However, E. eras-galli var. praticola was themore sensitive one to pretilachloa herbicide than such as E. oryzicola and E. eras-galli var. eras-galli, indicating that Echinochloa species might have a selective response to the annual herbicides tested.

• Korean Journal of Medicinal Crop Science
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• v.26 no.3
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• pp.220-226
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• 2018

Background: Atractylodes japonica Koidz. and Atractylodes macrocephala Koidz. belong to the family (Asteraceae). Their rhizomes, called white Atractylodes rhizomes, are used in traditional medicine. To address some issues with their cultivation, we recently developed eight hybrid cultivars by interspecific hybridization of A. japonica and A. macrocephala. This study was conducted to screen the hybrid cultivars that have high amounts of active ingredients and yield ability. Methods and Results: Experiments were conducted using the eight hybrid cultivars and A. macrocephala (control cultivar) in the experimental field of the department of Herbal Crop Research located in Eumseong, South Korea. We investigated the growth characteristics of the aerial and underground parts. Among the cultivars, 'Sanwon' had the highest rhizome dry weight (53.8 g/plant), followed by 'Dachul' (50.0 g/plant). In addition, the content of atractylenolide I, II, III and total active ingredients were investigated using high-performance liquid chromatography. Compared with A. macrocephala, most of the inter-specific hybrid cultivars had a higher content of active ingredients and yield ability. Conclusions: Through study, we established the superior quality of Atractylodes inter-specific hybrid cultivars. In particularly, it was found that 'Dachul' may be grown as a superior cultivar, with high amount of active ingredients as well as yield ability.

• Korean Journal of Medicinal Crop Science
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• v.26 no.5
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• pp.391-400
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• 2018

Background: Atractylodes radix is a well-known medicinal crop having many physiological effects. This study was conducted to select useful Atractylodes japonica ${\times}$ Atractylodes macrocephala (AJM) cultivars by comparing anti-oxidative and anti-inflammatory efficacies. Methods and Results: Seven extracts from AJM cultivars were used to treat lipopolysacchride (LPS)-treated BV2 cells, and the effects on cell viability and inhibition on reactive oxygen species (ROS) and nitric oxide (NO) production were analyzed. In vitro scavenging activities of 2,2-diphenyl-1-picrylhydrazyl (DPPH) and peroxynitrite ($NOO^-$) radicals were also investigated. Contents of total phenol, atractylenolide I, and atractylenolide III in the AJM extracts were measured using high performance liquid chromatography (HPLC) or spectrophotometry. The experiments show that none of the seven extracts was cytotoxic above 89.2% at $20-250{\mu}g/m{\ell}$. Extracts of Gowon, Dawon, Sangchul, and Huchul inhibited ROS generation in a dose-dependent manner, and Sangchul extract showed the highest inhibition on ROS production. All the AJM extracts showed effective inhibitory activity after on NO release in the LPS-treated BV2 cells, and Sangchul extract showed the highest activity. Sangchul extract had the most potent scavenging activities for $NOO^-$ and had some DPPH radical scavenging effect. Sangchul extract also had the highest content at total phenol and atractylenolide I content. Atractylenolide III was not detected in the AJM extracts. Conclusions: The results suggested that Sangchul was the most useful anti-oxidative and anti-inflammatory resource among the AJM cultivars.

• 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.

• Journal of Life Science
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• v.26 no.10
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• pp.1218-1223
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• 2016

Abalones are gastropod mollusks belonging to the genus Haliotis. Fishery products are continuously declining worldwide while abalone production from aquatic farms has considerably increased. Although abalones are regarded as very important marine resources and considered to have big potential in sea-food farming industry around world, the slow growth rate of Pacific abalones is considered to be one of the most serious problems. For the genetic improvements in cultured abalone, advances in various breeding techniques for abalone have been reached through the introduction of selection, crossbreeding, hybridization, and polyploidy in several commercially important abalone species. Six species of abalone have been reported to be distributed along the coasts of Korea: Haliotis discus hannai, Haliotis discus discus, Haliotis madaka, Haliotis gigantea, Haliotis diversicolor diversicolor, and Haliotis diversicolor supertexta. The hybridization between these abalones may be one of the advanced technologies, and the preliminary experiments of interspecific hybrids between abalone species distributed in northern pacific areas including Korea, China, and Japan have been conducted. In this study, we reviewed the phylogenetic relationship of northern pacific abalone species which have the potential traits for aquaculture in Korea and their identifications. We also examined the development of molecular markers and some other aspects of the genetic approaches for successful development of hybrids.

• Korean Journal of Plant Taxonomy
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• v.38 no.2
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• pp.79-91
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• 2008

Asplenium yoshinagae (Aspleniaceae), previously known only from Japan, southwest China to Himalaya, was found in Gageo-do, Heuksan-myeon, Sinan-gun, Jeollanam-do. This species is similar to A. trichomonas, A. tripteropus, A. boreale, A. normale and A. oligophlebium by having gemmae and auricle of pinna, and distinguished from the latters by distinct stipe length, stalk of pinna, acute apex of pinna, length of indusium and shape of sorus. The Local name, Ga-geo-kko-ri-go-sa-ri, was newly given considering the locality. To reveal the interspecific relationships within the genus Asplenium in Korea, cladistic analysis was performed for 22 taxa of Asplenium as ingroup and 2 taxa of Diplazium as outgroup from Korea based on 20 morphological characters. As the results, the genus Asplenium seperated strongly from outgroup, and divided into 4 clades. Asplenium yoshinagae belong to the third clade. A. hondoense N. Murtakami & S. I. Hatanaka, which contained in the second clade, had treated as Hymenasplenium, but this results supported that this taxon may be contained in Asplenium, and also, Asplenium ruprechtii, not in Comptosorus. The morphological characters and illustrations of the species are provided together with photographs of habitat.

• Journal of Ecology and Environment
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• v.29 no.6
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• pp.531-537
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• 2006

We assessed the species composition and structure of the three representative forest stands(Pinus densiflora stand, Quercus variabilis stand, and Ouercus mongolica stand), dominated in the National Long-Term Ecological Research Sites of Mt. Worak, Korea and established a benchmark series of permanent plots and transects with which future changes in forest composition and structure could be monitored. Species richness of Q. mongolica stand was greater than other two stands, due in large part to the greater habitat heterogeneity. Number of trees and species are decreased with increasing DBH classes. The successional trends of the three study stands would be mostly changed as Q. mongolica forest, regardless of forest types. Mean density ratio between alive trees and dead trees of three forest stands appeared with Q. mongolica stand 75:25, Q. variabilis stand 94:6, and P. densiflora stand 86:14, Q. mongolica stand appeared most highly from in three stands. This may be due to interspecific or intraspecific competition that it follows in various successesional stages. One side, when it saw the tree status which shows the tree health, the three forest stands all standing alive type (AS) appeared most highly with 75% to 85% and fallen dead type (DF) did not appear entirely. Remeasurement of permanent plots at periodic intervals will provide useful information on the dynamics of the forest vegetation that can be used in the development of adaptive conservation plans.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.2
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• pp.142-146
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• 1989

Anther and/or tissue culture of cross pollinated crops would be very important because it can result in the direct use of haploids or doubled haploids for developing superior hybrids or varieties. The objective of the study was to investigate the response frequencies in anther and/or tissue-cultured hybrids of corn. pearl millet and buckwheat to identify agronomically acceptable germplasm of the crops. 27 crosses of corn inbred lines were evaluated by plating their anthers on N6. MS and Yu-Pei media. Two genotypes of FR1l41/FR16 hybrid cultured on N6 medium and Fla 2BT73/S6013 hybrid cultured on N6 medium responded with one anther producing calli when plated after 5$^{\circ}C$ low temperature treatment for one week. Immature embryos of corn hybrid Suwon 19 responded producing calli that were regenerated to plants at a 8.6 percent success rate. Of the 20 corn hybrids. immature tessels of FR1l41/FR16. B68/A1l6N//KS15. KS16/KS17. GA209/DB578 and SDB126/GA209 crosses responded at a relatively higher success rate producing calli that were regenerated to plants. In tissue culture of elongating culms of pearl millet x Napier grass interspecific hybrid. 2.5-4.0mm long pieces of the culm were good for callus induction resulting in higher success rate. The epicotyl of buckwheat was very good for tissue culture. and the node produced the plants regenerated directly without callus induction on the B5 medium containing I ppm BA and 0.05 ppm IBA. There were great differences in response to anther and/or tissue culture of corn, pearl millet and buckwheat due to genotype x medium and environment interactions.

• Parasites, Hosts and Diseases
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• v.58 no.2
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• pp.153-159
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• 2020

The chigger mite Leptotrombidium sialkotense is one of the 6 main vectors of scrub typhus in China. Before present study, L. sialkotense was found in some parts of Hunan province, China with a narrow geographical distribution. During field investigation 2016-2017, we found L. sialkotense in Jingha, southern Yunnan, China. Of 15 small mammal host species, L. sialkotense were collected from 6 species of the hosts. Rattus brunneusculus was a dominant host of L. sialkotense, from which 98.3% of the mites were collected. The chigger mite showed a relatively high infestation prevalence (P_M =11.7%) and mean abundance (MA=0.5) in comparison with the rest 5 host species. These results reveal a certain host specificity of L. sialkotense to a rat R. brunneusculus. The mite L. sialkotense showed an aggregated distribution on the host (P<0.05). A positive correlation observed between L. sialkotense and the body length of hosts. There was a positive interspecific association between L. sialkotense and 2 other dominant vectors, L. deliense and L. scutellare.

• FLOWER RESEARCH JOURNAL
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• v.18 no.3
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• pp.193-200
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• 2010

Current rose cultivars are all composed of heterozygous genome due to long history of out crossing including interspecific hybridization. It has been adapted by artificial selection and crossing by breeders that mainly based on the crossing with fertile pollen derived from inter- or intra-specific hybridization. Pollen viability and germination ability tests provide valuable information for the designing of parentage for more successful breeding efficacy. In this study, we tested the pollen viability and germination ability in seven rose cultivars to find any relationship among several factors including pollen size, ploidy levels, and crossing compatibility. The pollen viability showed wide ranges from 39% 'Pinocchio' as minimum to 82% 'Scarlet Mimi' as maximum, whereas pollen germination rate were from 1% 'Mini Rosa' to 41% 'Scarlet Mimi' as a highest. Pollen size ranged from 41.3 to $45.4{\mu}m$ in large sized pollen and 30.7 to $37.4{\mu}m$ in small sized pollen. The mean diameter of large sized pollen is approximately 10-40% bigger than that of small sized pollen. There are positive relationships among ploidy level, total chromosome length, and pollen size. Crossing list showed that seed setting ratio and seed germination were related to pollen viability, pollen germination, and ploidy level.