• Korean Journal of Medicinal Crop Science
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• v.16 no.5
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• pp.320-325
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• 2008

Machilus thunbergii has been showed relation to antimicrobial activity on minimal inhibitoty concentration (MIC) and colony forming inhibitory activity (CFIA) test, so that can be used to food preservatives for green vegetable. Nanoparticles has been made of edible materials. 80% of the nanoparticles has been characterized by image analyser and electron microscopy, showing in the range under 300 nm diameter. The sprayed nanoparticles remained on the surface of chicon even after washing by dilution water, then activate biological activities for storage of chicon with storing and releasement system of extracts. Chicon treated nanoparticle has been kept fresh condition about 2 months longer than 3 weeks of the non-treated control. It can be tell that treatment with nanoparticle of M. thunbergii extracts extends storage time of chicon possibly by inhibition of ethylene production through efficiency control on cell breathing.

• Korean journal of applied entomology
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• v.55 no.3
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• pp.235-243
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• 2016

The winter cherry bug, Acanthocoris sordidus (Thunberg), is an insect pest hat damages plants from Solanaceae and Convolvulaceae. The developmental period from egg to adult averages 76 days at $25^{\circ}C$. Adult egg-laying occurred irregularly via spawning, averaging 195 (up to 468) eggs per individual on the abaxial leaf surface of the host plant. Results of linear regression indicated that the lower developmental threshold temperature was $13.9^{\circ}C$ and the effective accumulated temperature was 526.3 DD. Data from a pepper field in 2015 indicated that overwintering adults first appeared during late June (daily average temperature = $25.7^{\circ}C$), reaching maximum density by early September. A choice test examining colonization preferences using a net cage and a Y-tube olfactometer revealed that females gravitated toward conspecifics (other females, males, or both), whereas males moved toward empty areas. Finally, we found that communal breeding results in a longer developmental period and higher eclosion rates than solitary breeding. Developmental periods and eclosion rates were also for colonies in a large space than for those in a small space. This outcome suggests that colonization effects on insect development are stronger in a smaller area.

• Research in Plant Disease
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• v.9 no.4
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• pp.217-220
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• 2003

A severe fruit rot of Persimmon (Diospyros kaki cv: Fuyu) was occurred during the storage and transport that infected with blue mold in Sweet Persimmon Experiment Station, Gyeongsangnam-do Agricultural Research and Extension Services, Korea. Fruit surfaces were infected with the fungus first and the colonized fungus formed mycelial mats. From the point of infection, fruits become collapsed and mostly ruptured. The pathogenic fungus from infected fruits was isolated and cultured on PDA. Colony color of the fungus was white at frist than became green on Malt Extract Agar and Czapek Yeast Extract Agar. Conidia were ellipsoid subglobose and 2.6${\sim}$3.8 ${\times}$ 2.4${\sim}$3.8 ${\mu}m$ in size. Stipes were 86${\sim}$320 ${\times}$ 2.8${\sim}$4.3 ${\mu}m$ in size. Rami were 7.5${\sim}$32.6 ${\times}$ 2.6${\sim}$4.2 ${\mu}m$ in size, Ramuli were 12.4${\sim}$14.8 ${\times}$ 3.2${\sim}$3.8 ${\mu}m$ in size, Metulae were 8.9${\sim}$13.6 ${\times}$ 2.8${\sim}$4.6 ${\mu}m$ in size. Phialides were ampulliform, 8.2${\sim}$12.4 ${\times}$ 2.3${\sim}$3.6 ${\mu}m$ in size. Based on the cultural and mycological characteristics and pathogenecity test on host plants, the fungus was identified as s, This is the first report on the blue mold of Persimmon (Diospyros kaki) caused by P. crustosum in Korea.

• Research in Plant Disease
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• v.13 no.3
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• pp.211-215
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• 2007

Since 2003, anthracnose symptoms on Eucalyptus globulus were observed in farmer's field at Jisepo, Ilwoon-myon, Geoje city, Gyeongnam province, Korea. Typical symptoms of dark brown to black spot appeared on the leaves, twigs, and stems. Infected young trees were wilted, blighted and died eventually. The pathogen isolated from the typical symptom formed gray to dark gray colony on potato dextrose agar and showed optimum growth at $30^{\circ}C$. Conidia were single celled, colorless, cylindrical with obtuse ends, and $9{\sim}22{\times}3{\sim}6{\mu}m$ in size. Appressoria were dark brown, ovate to obovate, and $6{\sim}18{\times}4{\sim}10{\mu}m$ in size. Perithecia were black and globose in shape and $76{\times}274{\mu}m$ in size. Asci were clavate to cylindrical in shape and $42{\sim}76{\times}8{\sim}12{\mu}m$ in size. Ascospores were cylindrical, fusiform, slightly curved at the center, and $10{\sim}23{\times}4{\sim}6{\mu}m$ in size. On the basis of mycological characteristics and pathogenicity test on E. globulus, the pathogen was identified as Glomerella cingulata. This is the first report of the anthracnose on E, globulus caused by G. cingulata in Korea.

• Korean Journal of Organic Agriculture
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• v.22 no.1
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• pp.129-145
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• 2014

To evaluate the potential of Hypochoeris radicata L. for the development of environment-friendly organic materials, its growth characteristics, allelopathic effects and antifungal activity was investigated. The growth characteristics of H. radicata L. was investigated by measuring comparative number of shoot and flower, and the diameters of clones in mowing areas and non-mowing areas, respectively. As a result, the number of shoot and flower, and diameters of clones of H. radicata L. grown in mowing areas were much higher than those grown in non-mowing areas. Water extracts of H. radicata L. inhibited seed germination, and shoot, root and root hair growth of 14 test plants including Trifolium pratense, Festuca myuros, Bidens bipinnata and finally reduced heir biomass remarkably. The inhibitory effect of the extract was different depending on the kind and the part of tested plants. The extracts showed high antifungal activity against Pythium spp. and Phytophthora However, it showed comparably less antifungal activity against Rhizoctonia solani than Pythium spp. and Phytophthora. In conclusion, cutting H. radicata L. resulted increase of its vegetative and seed propagation and helped it to form large colony. Also it had an effect on growth of microbes and germination and growth of other plants. Therefore H. radicata L. holds the competitive dominant position in plant ecosystem in Jeju Island and it can be used as candidate of environment-friendly organic materials.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.17
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• pp.7297-7301
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• 2014

Objective: To explore the radiosensitization effect of overexpression of silent information regulator 6 (SIRT6) on A549 non-small cell lung cancer (NSCLC) cells. Methods: Adenovirus vector Ad-SIRT6 causing overexpression of SIRT6 was established. Western blotting and MTT assay were adopted to detect the level of SIRT6 protein and the inhibitory rate of A549 cell proliferation after different concentrations of adenovirus transduction (0, 25, 100, 200, and 400 pfu/cell) for 24 h. Control group, Ad-null group and Ad-SIRT6 group were designed in this experiment and virus concentration of the latter two groups was 200 pfu/cell. Colony formation assays were employed to test survival fraction (SF) of the 3 groups after 0, 2, 4, 6, 8, 10 X-ray irradiation. Flow cytometry was used to detect the status of cell cycle of 3 groups after 48 h of 4Gy X-ray irradiation and Western blotting was used to determine the expression of apoptosis-related genes of 3 groups after 48 h of 4GyX-ray irradiation. Results: In the range of 25~400 pfu/cell, the inhibitory rate of A549 cell proliferation increased as adenovirus concentration raised. The inhibitory rates under the concentrations of 0, 25, 100, 200, and 400 pfu/cell were 0%, $4.23{\pm}0.34%$, $12.7{\pm}2.57%$, $22.6{\pm}3.38%$, $32.2{\pm}3.22%$, $38.7{\pm}4.09%$ and $47.8{\pm}5.58%$ and there were significantly differences among groups (P<0.05). SF in Ad-SIRT6 group was lower than Ad-null and control groups after 4~10Gy X-ray irradiation (P<0.05) and the sensitization enhancement ratio (SER) was 1.35 when compared with control group. Moreover, after 48 h of 4Gy X-ray irradiation, there appeared a significant increase in G1-phase cell proportion, upregulated expression of the level of apoptosis-promoting genes (Bax and Cleaved caspase-3), but a obvious decline in S-phase and G2-phase cell proportion and a significant decrease of the level of apoptosis-inhibiting gene (Bal-2) in the Ad-SIRT6 group (P<0.05). Conclusion: The over-expression of adenovirus-mediated SIRT6, which has radiosensitization effect on A549 cells of NSCLC, can inhibit the proliferation of A549 cells and cause G0/G1 phase retardation as well as induce apoptosis of cells.

• Research in Plant Disease
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• v.8 no.4
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• pp.220-223
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• 2002

In April of 2002, fruit rot infected with blue mold was found at maturing stage of melon (Cucumis melo cv. Gayabaegja) growing under tunnel cultivation in Daesan-myon, Haman-gun, Gyeongnam Province, Korea. Floral parts were infected first and colonized by fungal mycelial mats. From the point of infection, fruits become collapsed and mostly ruptured. The pathogenic fungus from infected fruits was isolated. Colony color of the fungus was white on MEA and CYA agar, Conidia were ellipsoid and 2.6~7.4$\times$2.6~5.8 ${\mu}{\textrm}{m}$ in size. Stipes were 86~320$\times$2.8~4.3 ${\mu}{\textrm}{m}$ in size. Metulae were 12.4~31.6$\times$2.6~4.2 ${\mu}{\textrm}{m}$ in size. Phialides were ampulliform to cylindroid, and 8.2~15.4$\times$3.6~4.6 ${\mu}{\textrm}{m}$ in size. Rate of infected fruits in the field was 4.3%. Based on the cultural and mycological characteristics and pathogenecity test on host plants, the fungus was identified as Penicillium oxalicum, This is the first report on the blue mold of melon (Cucumis melo) caused by P. oxalicum in Korea.

• Korean Journal of Soil Science and Fertilizer
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• v.30 no.2
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• pp.200-207
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• 1997

In order to evaluate the soil microbiological characteristics of paddy fields in Korea, surface soils were sampled from 63 sites in different agroclimatic zones before submersion of the fields. The distribution of microorganisms and the microbial diversity indices were examined. Soil microbial populations were generally higher in southern area than in northern area. The colony forming units(cfus) of fluorescence Pseudomonas sp. showed the greatest regional differences, among the microbes investigated. On the topographical differences, the cfus of aerobic bacteria, fluorescence Pseudomonas sp. and Azotobacter sp. maintained high level in coastal plains; and on the sail textural difference, fungus was the highest in clay soil, but Bacillus sp., Azotobacter sp and denitrifiers were the highest in silty clay loam soil at 0.05 probability level based on the multiple range test. The numbers of ammonium oxidizers and Azotobacter sp. were increased with soil pH. Microbial diversity indices of paddy fields which calculated from the percentages of Bacillus sp. fluorescence Pseudomonas sp. Azotobacter sp. denitrifiers, ammonium oxidizers, nitrite oxidizers, actinomycetes and fungus to these total microbial numbers were between 0.109 and 0.661. On the soil textures, the microbial diversity indices of sandy, sandy loam, silty clay loam, clay loam and clay soil were 0.443, 0.427, 0.414, 0.405 and 0.362 respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.2
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• pp.218-221
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• 2002

Whole forage sorghum (saccharatum) cultivar FS5 was harvested at the soft dough ($303{\pm}9g\;kg^{-1}$ DM) stage of maturity. The sorghum was chopped into approximately 20 mm pieces and ensiled under laboratory conditions in 1.5 L Weck glass jars. At ensiling, it was treated with two commercial silage inoculants: Pioneer 1188 (Inoculant A) and Eco-corn (Inoculant B). The inoculant A and B was applied at ca $2{\times}10^5$ or $2{\times}10^4$ colony forming units $g^{-1}$ DM., respectively. Silage with no additives served as a control. Three jars per treatment were opened on days 2, 4, 8, 15 and 60 post-ensiling to study fermentation dynamics. After 60 days of ensiling the silages were analyzed and subjected to an aerobic stability test lasting 5 days. Results showed that both inoculants caused a more rapid rate of pH decrease and a higher amount of lactic acid production. All the silages were well preserved and were stable upon exposure to air. Inoculants did not influence (p>0.05) the ash and total N contents, but tended to reduce acetic acid (p<0.05), butyric acid (p<0.01) and propionic acid (p<0.01) contents, and to increase the lactic acid content (p<0.01). The lower DM content of silages treated with Inoculant A agrees with the greater gas loss resulting from the DM loss, which was in good agreement with the higher yeast counts upon aerobic exposure. Silage treated with inoculant B had the highest DM (p<0.05) and lactic acid contents (p<0.01), and the lowest acetic acid content (p<0.05), which agrees with the rapid reduction of pH and smaller gas loss. Inoculant B reduced the ADF (p<0.01), ADL and NDF (p<0.05) contents, which also indicates smaller losses of organic soluble material. The control silages contained the highest levels of volatile fatty acids but no lactic acid, indicating secondary fermentation. It was concluded that both inoculants may improve the fermentation process, since silages from all treatments were stable upon aerobic exposure, noadvantage could be attributed to any of the inoculants used.

• Research in Plant Disease
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• v.23 no.1
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• pp.56-59
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• 2017

During growing season of 2011 to 2013, Sclerotinia rot symptoms consistently have been observed on basil in Yesan-gun, Chungcheongnam-do in Korea. The typical symptom formed initially brownish spot on leaf and stem, and then advancing margins, wilting the whole plant and blighting, eventually died. On the surface of diseased lesions was observed cottony, white, dense mat of mycelial growth, and sclerotia ($30-100{\mu}m$ diameter) formed on stem and leaf. Morphological and cultural characteristic on potato dextrose agar, color of colony was white and colorless chocolate, sclerotium of irregular shape of the oval was black and $5-50{\mu}m$ diameter in size. In pathogenicity test, necrosis and wilt of the inoculated stem were observed in all plants and the pathogen was reisolated from stems. On the basis of mycological characteristics, pathogenicity, and internal transcribed spacer rDNA sequence analysis, this fungus was identified as Sclerotinia sclerotiorum. This is the first report of Sclerotinia rot on basil caused by S. sclerotiorum in Korea.