• The Plant Pathology Journal
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• 제23권2호
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• pp.70-75
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• 2007

We conducted an inoculation test using nine open-pollinated families of pine trees to evaluate their susceptibility and mortality in different densities of pine wood nematode. Three-year-old nine open-pollinated pine families were inoculated with Bursaphelenchus xylophilus at levels of 3,000, 5,000, and 7,000 nematodes/seedling in greenhouse. There were no distinct patterns in latent period among three densities of B. xylophilus in all families. Most families showed the first disease symptoms of needle discoloration within 12-15 days after inoculation. However, open-pollinated progenies of Pinus densiflora showed the longest latent period because none of one-year-old needles were wilted until 14 days after inoculation with 5,000 and 7,000 nematodes. One-year-old needles were wilted earlier than current needles in all tested families with all densities of B. xylophilus. Current needles were not wilted until 14 days after inoculation in all seedlings. The mortality of all seedlings rapidly increased from 35 days to 49 days after inoculation, and all died within 80 days except two seedlings. A 3,000 nematodes/100 ${\mu}L$ with sterilized distilled water are enough to screen 3-year-old pine seedlings for resistance to B. xylophilus.

• Applied Biological Chemistry
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• 제46권1호
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• pp.12-15
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• 2003

클로렐라를 첨가하여 기능성 두부를 제조함에 있어 클로렐라의 첨가량이 두부의 품질에 미치는 영향을 조사하였다. 건조 대두를 기준으로 클로렐라를 0.5-2.0% 첨가하여 제조한 두부의 수율, 물성, 색도, 저장성 및 관능적인 특성을 클로렐라를 첨가하지 않고 제조한 일반두부와 비교하였다. 수율은 클로렐라를 1% 첨가한 경우 일반두부에 비하여 10% 이상 향상되었다. 클로렐라를 첨가함으로써 두부의 물성 중 견고성, 검성과 씹힘성이 증가하였으며, 색도는 L값, a값, b값 모두 첨가량에 비례하여 감소하였다. 관능적 특성은 조직감 이외의 항목에서는 일반두부와 통계적으로 유의적인 차이가 얼었다. 제조한 두부를 $15^{\circ}C$로 보관하면서 pH와 총균수의 변화를 측정한 결과 클로렐라를 0.5-1.0% 첨가한 두부에서 pH하락과 미생물 생육이 효율적으로 지연되었다.

• 한국식물병리학회지
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• 제14권4호
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• pp.339-344
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• 1998

Since the leaf inoculation procedures are time-consuming and require considerable growth chamber space, a rapid dioassay method for screening of pathogenicity of Didymella bryoniae, a casual agent of gummy stem blight in watermelon, was established in this paper. The method produced reliable results within 8 days ( 5 days for growing seedlings and 3 days for rapid disease response in the seedlings). After contaminants in the root of 4~5 day-old seedlings had been washed using sterilized water, 5 seedlings were dipped into a vial containing 12 ml of conidial suspension (106 cells/ml). After the vials were placed in a growth chamber (22$^{\circ}C$, RH 50%, 14hr light/10hr darkness) for 3 days, susceptibility and resistance of cultivars were determined by the degree of disease response on cotyledon. The result of obtained by the dip-inoculation method was well coincided with the results by the leaf inoculation procedures and the result that had been observed for several years in the field. Screening of collected watermelon cultivars by the dip-inoculation method revealed that all the 21 domestic cultivars collected were susceptible and only 3 foreign cultivars (PI 189225, PI 482322 and IT 188207) were resistant among 18 cultivars A cucumber cultivar (Marketer) and bitter cucumber were proven to be resistant against the D. bryoniae among 8 other different cucurbits tested. The SDS-PAGE patterns of total proteins from a susceptible (Keumcheon) and a resistant (PI 189225) watermelon cultivars were compared 0, 12, 24 and 36 hrs after inoculation. The amounts of two distinct protein bands (24 kDa and 70 kDa) were gradually increased after inoculation in both cultivars.

• 한국양식학회지
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• 제11권1호
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• pp.91-97
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• 1998

이 연구에서는 해산어의 종묘 생산에 필요한 대량 배양용 로티퍼, Brachionus rotundiformis의 종 보존 방법으로서 무균 로티퍼의 이용을 검토했다. 로티퍼는 개량형 항생제 혼합액 AM9을 사용하여 무균 처리한후, 무균 Nannochloropsis oculata를 먹이로 공급하여 연속 유지 배양했다. 각각 다른 시기의 3회 (trial 1, 2 and 3)에 걸친 로티퍼 배양결과, 무균 배양 (axenic culture)에서는 비교적 안정적인 증식을 보인 반면, 유균 배양 (non-axenic culture)에서 로티퍼의 증식은 불안정적으로 각 시기에 따라서 심한 증식의 차이가 관찰되었다. 이 결과는 유균 배양에서 로티퍼의 증식에 직접적으로 악영향을 미치는 박테리아가 무균 처리과정을 통해서 제거되었음을 증명한다. 로티퍼 무균 배양 방법의 일반화 또는 대량 배양용 로티퍼의 씨앗으로서의 무균 로티퍼의 이용은 로티퍼의 안정 배양은 물론 유용 수산 생물의 대량 폐사를 일으키는 원인 생물을 사전에 제거할 수 있는 유효한 방법이 될 수 있다고 생각된다.

• Advances in Traditional Medicine
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• 제3권2호
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• pp.106-110
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• 2003

Respiratory syncytial virus (RSV) has long been considered an important cause of severe lower respiratory tract infection in infants and young children throughout the world. Unfortunately, no effective treatment of RSV exists. Therefore, New agents are needed to reduce the impact of RSV. We have studied the anti-viral effect of traditional Chinese midicinal herbs for over ten years and find Herba Patrinea (a Chinese medicinal herb) has the anti-RSV effect in vitro. In this study, the Herba Patrinea was extracted with hot water, condensed and sterilized. The cytotoxicity of the aqueous extract was tested by adding the diluted extract directly to HeLa cells and its effect on anti-RSV was estimated by the CPEI assay. As a result, the median cytotoxic concentration $(CC_{50})$ of Herba Patrinea was 32 mg/ ml by morphological observation, the median effective concentration (50% effective concentration, $EC_{50}$) of the Herba Patrinea against replication of the Long strain of RSV in HeLa cells were 1.25 mg/ml. The selectivity index $(SI=CC_{50}/EC{50})$ is 25.6. Moreover, Herba Patrinea gave a dose-dependent response in inhibiting RSV. In time of addition experiment, Herba Patrinea inhibited replication of RSV in HeLa cells when it was added at 0h, 2h, and 4h after virus infection. In summary, the results of this study suggest Herba Patrinea may be a novel anti-RSV drug and it is worthy of further studying.

• The Plant Pathology Journal
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• 제23권3호
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• pp.223-225
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• 2007

Many plant growth-promoting rhizobacteria (PGPRs) have been known for beneficial effects on plants including biological control of soilborne pathogens, induced systemic resistance to plant pathogens, phytohormone production, and improvement of nutrient and water uptake of plants. We developed a simple and rapid method for screening potential PGPR, especially phytohormone producing rhizobacteria, or for analyzing their functions in plant growth using cucumber seedling cuttings. Surface-sterilized cucumber seeds were grown in a plastic pot containing steamed vermiculite. After 7 days of cultivation, the upper part 2 cm in length of cucumber seedling, was cut and used as cucumber cuttings. The base of cutting stem was then dipped in a microcentrifuge tube containing 1.5ml of a bacterial suspension and incubated at $25^{\circ}C$ with a fluorescent light for 10 days. Number and length of developed adventitious roots from cucumber cuttings were examined. The seedling cuttings showed various responses to the isolates tested. Some isolates resulted in withering at the day of examination or in reduced number of roots developed. Several isolates stimulated initial development of adventitious roots showing more adventitious root hair number than that of untreated cuttings, while some isolate had more adventitious root hair number and longer adventitious roots than that of untreated control. Similar results were obtained from the trial with rose cuttings. Our results suggest that this bioassay method may provide a useful way for differentiating PGPR's functions involved in the development of root system.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.412-412
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• 2014

Zinc oxide (ZnO) is one of the most powerful materials for purifying organic pollutants using photocatalytic activity. In this study, we have introduced a novel method to design highly photoreactive flexible 3 dimensional (3D) ZnO nanocomposite [F-ZnO-m (m: reaction time, min)] by electrospinning and simple-step ZnO growth processing (one-step ZnO seed coating/growth processing). Significantly, the F-ZnO-m could be a new platform (or candidate) as a photocatalytic technology for both morphology control and large-area production. The highest photocatalytic degradation rate ([k]) was observed for F-ZnO-m at 2.552 h-1, which was 8.1 times higher than that of ZnO nanoparticles (NPs; [k] = 0.316 h-1). The enhanced photocatalytic activity of F-ZnO-m may be attributed to factors such as large surface area. The F-ZnO-m is highly recyclable and retained 98.6% of the initial decolorization rate after fifteen cycles. Interestingly, the F-ZnO-m samples show very strong antibacterial properties against both Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus) after exposure to UV-light for 30 min. The antibacterial properties of F-ZnO-m samples are more effective than those of ZnO NPs. More than 96.6% of the E. coli is sterilized after ten cycles. These results indicate that F-ZnO-m samples might have utility in several promising applications such as highly efficient water/air treatment and inactivation of pathogenic microorganisms.

• Mycobiology
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• 제29권4호
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• pp.218-223
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• 2001

A rapid radicle assay for prescreening antagonistic bacteria to Phytophthora capsic4 causal agent of Phytophthora blight of pepper was developed. Sixty-four bacterial strains with in vitro antifungal activity selected out of 1,400 strains isolated from soils of Ansung, Chunan, Koyang, and Paju, Korea in 1998 were used for development of the bioassay. Uniformly germinated pepper seeds dipped in bacterial cells for 3 hours were placed near the edges of growing mycelia of P. capsici on water agar containing 0.02% glucose. Five-week-old pepper plants(cv. Nockwang) were inoculated to compare with results of the radicle assay developed in this study. For plant inoculation, pepper seeds were sown in potting mixtures incorporated with the bacterial strains, then transplanted into steam-sterilized soils 3 weeks later. Plants were hole-inoculated with zoospores of P. capsici 2 weeks after transplanting. Disease incidence and severity were determined in radicle and plant assessments, respectively. In radicle assay, six strains, GK-B15, GK-B25, OA-B26, OA-B36, PK-B09, and VK-B14 consistently showed the significant(P=0.05) disease reduction against radicle infection by the fungus, four of which also did in plant assessments. Strains OA-B36 and GK-B15 consistently reduced the fungal infection in both the radicle assay and the plant assessment. Therefore, prescreening strains using the radicle assay developed in this study followed by plant assay could reduce time and labor, and improved the possibility of selecting antagonistic bacteria for control of Phytophthora blight of peppers.

• 식물병연구
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• 제7권3호
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• pp.134-139
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• 2001

잿빛곰팡이병균 Botrytis cinerea LVF12 분생포자의 토마토 잎 감염에 미치는 영양원의 영향을 조사하고 병원성을 검정한 결과, 0.1M KH$_2$PO$_4$를 첨가한 20% 토마토 쥬스로 만든 분생포자 부유액이 토마토 잎에서 일정하면서도 높은 발병도를 보여 감염에 효과적인 분생포자 영양원으로 선발하였다. 또한 토마토의 생육 단계별로 병원성을 검정한 결과, 유묘보다 성숙한 식물일수록 발병도가 높았고 하위엽이 상위엽보다 발병도가 높았다. 병징은 감염 초기에 갈색의 소형 점무늬가 잎에 형성되고 병반이 잎자루와 줄기까지 진전되면서 잎이 탈락하거나 줄기 전체가 갈변하여 고사하였다. 감염된 열매는 초기에 암갈색의 원형 병반이 형성되고 점점 진전되면서 열매가 물러 썩었는데, 습도가 높을 때에는 병든 잎, 줄기 및 열매가 잿빛의 균사와 분생포자로 뒤덮혀 자연 발생된 병징과 동일한 특성을 보여 주었다.

• 한국작물학회지
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• 제23권2호
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• pp.113-117
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• 1978

대두 자반병에 대하여 저항성인 계통 선발을 위한 Mass-screening technique를 확립하고 이 종자잡종법을 이용하여 수집재내종 및 각 품종의 저항성검정을 실시한 결과는 다음과 같다. 1. 조숙성인 수집재내종 50계통의 자반병 자연감염률과 종자접종에 의한 자주빛 색소 형성률간에 나타난 정의 상관관계는 r=0.121로서 고도의 유의성이 인정되었으며 이 종자접종법은 효과약인 Mass-screening technique으로서 방사선을 이용한 돌연변이육종에서 자반병저항성 계통선발에 이용가능성이 높았다. 2. 자반병 자연감염률이 극히 낮은 만숙성 수집재내종 85계통은 종자접종에 의하여 대부분이 이병성 반응을 보였으며 이는 포장에서의 만숙계통의 저항성이 유전적인 특성이기 보다는 병해도피 현상에 기인한 것으로 생각되었다. 3. 대두품종의 저항성검정에서 우리나라 대두 36품종을 비롯하여 일본과 대만의 각 16품종, 베트남 11품종, 필리핀 8품종 및 미국 38품종 등 대부분이 이병성이였고 미국품종인 Sac, Hill, Harosoy등이 비교적 저항성 이었다. 4. 각 지역에서 분리한 대두 자반병균 244 isolates 중에서 배지에서 자주빛 색소를 형성하지 않는 두 균주를 제외하고는 모두가 암조건에서는 감자한천배지에서, 광조건에서는 오트밀한친배지에서 자주빛 색소형성이 잘 되었으며 배지에서의 색소형성 정도는 종자에서의 병원성과 밀접한 상관이 있었다.