• Research in Plant Disease
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• 제12권2호
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• pp.69-74
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• 2006

Basal rot of freesia caused by a Sclerotium sp. occurred at Incheon areas. Incidence of the disease reached up to 45% and averaged 17.0% in the fields. Typical symptoms consisted of sheath dry and leaf blight due to rots on basal leaves. The causal fungus was identified as Sclerotium sp. based on following mycological characteristics. The fungus formed sclerotia on cultural media and plant tissues, but did not produce asexual spores. On cultural medium, aerial mycelia of the fungus changed color from white to clay with cultural age and smelled musty odor. Numerous irregular and elliptical black microsclerotia of the fungus were formed on potato dextrose agar (PDA) after 5 days of incubation at $25^{\circ}C$ and sized $115{\sim}200{\times}95{\sim}150 (av. 145{\sim}126.5){\mu}m$. The fungus grew at $10{\sim}32^{\circ}C$ and $pH 4.0{\sim}8.5$. However, the optimal temperature and pH for mycelial growth of the fungus were $24^{\circ}C$ and 5.5 respectively. The isolate showed present pathogenicity to not only freesia but gladiolus in the pathogenicity test, and the symptoms were similar to those observed in the fields. Basal rot of freesia caused by Sclerotium sp. is firstly reported in Korea.

• Journal of Plant Biotechnology
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• 제29권1호
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• pp.19-23
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• 2002

This experiment was conducted to micropropagate bulblets via shoot cluster formation and massproduce normal bulblets from the sections of proliferated shoot clusters in Lilium asiatic hybrid 'Hae Hwa'. The induction of shoot clusters from the culture of bulblet sections was more effective than that of bulb scales on MS medium with 1.0 mg/L BA and 0.5 mg/L IAA. Proliferation of shoot clusters from the formed shoot cluster sections was the most favorable on medium containing 5.0 mg/L BA and 0.5 mg/L IAA. The formation and the growth of bulblets from shoot cluster sections were achieved effectively on medium with 60∼90 g/L sucrose. The leaves derived from shoot clusters grew vigorously but the bulblets from shoot clusters grew very poor in 5L air-lift bioreactor culture. By the addition of 30 mL fresh liquid medium containing doulble strength MS salts, 250 g/L sucrose and 5 g/L activated charcoal after 8 weeks in the shoot cluster culture on MS medium with 5.0 mg/L BA and 0.5 mg/L IAA, the number of bulblets was increased in light condition, but the growth of bulblets was not affected by light. Bulblet production was possible with the bulblet product at 53 to 68 mg in fresh weight by liquid medium addition after the proliferation of shoot cluster.

• Journal of Physiology & Pathology in Korean Medicine
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• 제17권4호
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• pp.905-913
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• 2003

Oriental medicine explains aging as the weakening of Kidney-ai, and Kidney-strengthening herbal medicines such as Yukmijihwang-tang have been studied for anti-aging effects. In Western Medicine, the hypothesis that reactive oxidant species(ROS) contribute to the aging process is generally accepted. It has been reported that Moutan Cortex Radicis extract (MCR) was the most effective constituent of Yukmijihwang-tang in decreasing ROS production in oxidative-stressed cells. The purpose of this study is to confirm the anti-oxidant effect of MCR on PC12 cells, the expression of Heme oxygenase (HO), Macrophage migradon inhibitory factor (MIF), Catechol-O-methyltransferase (COMT) using real time RT PCR. PC12 cells were treated without or with hydrogen peroxide in the presence or absence of MCR using MTS assay. Hydrogen peroxide decreased the viability of PC12 cells by 53% and MCR did not influence that of stressed PC 12 cells irrespective of dose or incubation period. However, MCR showed an inhibitory effect on production of ROS in stressed cells, both dose and incubation time dependently. In particular, 1 ㎎/㎖ of MCR for 24 h culture almost returned to normal level. In the quantiation of anti-aging related gene expression, MCR at 1 ㎎/㎖ increased the expression of HO by 370%, MIF by 180% and COMT by 280% through real time RT PCR. In conclusion, MCR treatment protected PC12 cells from hydrogen peroxide and decreased ROS production and enhanced anti-oxidative gene expression such as HO, COMT and MIF, which suggests that MCR is involved in controlling anti-aging of nerve cells through elimination of cytotoxic stimuli.

• Journal of the Korea Academia-Industrial cooperation Society
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• 제18권4호
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• pp.67-74
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• 2017

This study analyzed the antioxidant activities and antibacterial effects of extracts from the fruit of Citrus junos. Theextracts were obtained in both 70% ethanol solution and distilled water at a distillation temperature of $50^{\circ}C$.Three experiments were carried out between November 2016 and March 2017. The averages and the standard deviations of the results were measured. The total polyphenol and tannin contents of the ethanol extracts were $7.8{\pm}0.02mgGAE/g$ and $9.9{\pm}0.01mgTAE/g$, respectively, which were higher than the concentrations in the water extracts. Furthermore, the ethanol extracts scavenged $46.1{\pm}4.76%$ of DPPH radicals and $37.1{\pm}1.23%$ of ABTS radicals. The scavenging capability of the ethanol extracts was also higher than that of the water extracts. However, the scavenging capability of both types of extracts depended on their concentrations.All the extracts showed active antibiosis effects against every bacteria tested except for C. albicans. E. coli at 25 mg/disc showed antibiosis with $18{\pm}1.73mm$ for the water extracts, while S. epidermidis and S. aureus showed antibiosis with $17{\pm}4.36mm$ and $19{\pm}2.86mm$ for the ethanol extracts, respectively. This antibiosis rate is considerably higher. The results suggest that fruit extract from Citrus junos could be useful as a primary material for beauty or skin-related products such as soaps, shampoos, and scalp enhancers.

• FLOWER RESEARCH JOURNAL
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• 제18권1호
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• pp.29-32
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• 2010

This study was conducted to determine the effects of cutting position, media, and auxin on rooting of Artemisia keiskeana cuttings. In the cutting positions, the cutting of middle and basal positions had a better growth in the both upper and lower part than the cutting of the top position. Especially, the cutting of the middle position showed the highest rooting rate, at 68.3%. In the media, peatmoss showed the latest date on the rooting initiation. Also, the growth, survival rate and rooting rate of the upper part and lower part were low. However, the cutting in vermiculate showed the fastest date on the rooting initiation, and had a significant effect on the growth of the upper part and lower part, showing the highest rooting rate and survival rate in all tested media. When cuttings were treated by auxin, the rooting rate and growth of cuttings were higher than the control. The control showed the lowest rooting rate, at 41%, while, the auxin treatment showed the highest, rate over 80%. Whereas when treated by NAA, the lower part of cuttings had a better growth than these treated by IBA. Also, the higher the concentration of auxin was, the higher the rooting rate and growth rate of Artemisia keiskeana cuttings were.

• Korean Journal of Plant Taxonomy
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• 제46권4호
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• pp.371-377
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• 2016

The succulent herbaceous perennial Sedum sarmentosum commonly grows in the southern part of the Korean Peninsula. It is a species native to China, most likely introduced into Korea due to its edible and medicinal uses. If plants were introduced from a single source, we would expect no or low levels of genetic variation in Korean populations. Alternatively, if plants were introduced from multiple sources, we would expect, in contrast, high levels of genetic diversity. To test which is more likely, we surveyed the degree of allozyme variation in ten populations of this species from southern Korea. We found that S. sarmentosum was monomorphic at all fifteen allozyme loci. However, two congeners (S. polytrichoides and S. kamtschaticum) and two related species (Hylotelephium ussuriense and H. verticillatum) maintain moderate to high levels of genetic diversity ($H_e=0.144$, 0.203, 0.201, and 0.204, respectively). We suggest that southern Korean populations of S. sarmentosum likely descended from a single introduction of a few plants and then became naturalized exclusively via vegetative spreading (as plants in Korea, but also as occurs in other parts of its native and naturalized range, are sterile).

• Korean Journal of Soil Science and Fertilizer
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• 제22권1호
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• pp.1-5
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• 1989

This study was carried out by using laboratory data to calculate Soil Moisture Control Section (SMCS) for medium textured topo-sequential soils derived from porphyry in Milyang area. The soils studied were characterized by loam to silty clay loam, and the moisture content at -1/3 bar in the solum ranged around 21.06% to 32.42%. The moisture contents per centimeter of soil layer within a solum calculated at field capacity (FC) ranged from 0.11cm to 0.19cm. The upper boundaries of SMCS of the soils calculated on the basis of FC as the water content at -1/3 bar, ranged from 16.2cm to 21.2cm and the lower boundaries from 44.4cm to 63.8cm, and the depth of SMCS were from 27.7cm to 42.6cm in the soil profiles. The Bongsan soil on the summit had shallower in the boundaries and narrower in the depth of SMCS than the soils on side-slopes or on valley.

• Korean Journal of Soil Science and Fertilizer
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• 제33권3호
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• pp.153-159
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• 2000

This study was carried out to develop a more convenient way to analyze soil texture by hydrometer. Standard Hydrometer Method(SM), in which at least 7 times of reading is required for soil texture analysis, was compared with two other methods named as Soil Clay Fraction Procedure(SCFP) and Simplified for Soil Texture Analysis(SSTA), in which 2 or 3 times of hydrometer reading may be enough for soil texture analysis, respectively. There appeared to be very close correlation(nearly 1.0) between clay contents measured by the above three methods. The clay content measured by SCFP were overestimated by 0~2 percent than those by SM. Textural classes of 28 soil samples determined by SSTA were identical to those by SM. But, textural classes determined by SCFP appeared to be different from those by SM in 4 of 28 soil samples. Because the measurements of particle size in SSTA is made near $2{\mu}m$ diameter, we can save time and labour to measure the clay contents. Therefore, SSTA could be used as a more convenient method to get the same data as SM.

• Korean Journal of Soil Science and Fertilizer
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• 제28권2호
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• pp.145-153
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• 1995

Effects of lime application levels(0, 10, 50, 100, and 300kg/10a) on three alfalfa cultivars(Dekalb brand 120, Pike, Pioneer brand 5929) were analyaed with respect to the growth, dry matter yield, and inorganic composition of the plants at three cutting periods. Major chemical properties of the soils were also analyzed. Response of the plant height to the lime application level was variable among the cultivars, showing the order of 50>100>300>10>0kg/10a in Dekalb brand 120, 50>100>10>300>0kg/10a in Pike, and 10>50>300>0>100kg/10a in Pioneer brand 5929. The order of dry matter yield response to the lime application level was 50>300>100>10>0kg/10a in Dekalb brand 120, 50>10>300>100>0kg/10a in Pike, and 50>100>10>0>300kg/10a in Pioneer brand 5929. Total dry matter yields at 50kg/10a lime application level were higher than those at any other levels in all the cultivars. Neither a specific pattern nor a significant change in inorganic composition of the plant was found for the lime application levels and cutting times, Soil chemical properties and composition remained with little change after the experiment except the soil pH, which was increased with the lime application level.

• Korean Journal of Ichthyology
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• 제33권3호
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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.