• Mycobiology
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• 제39권4호
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• pp.303-305
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• 2011

One rare and interesting species collected from Gyeryong-san, Chungnam Province is described and illustrated in detail. The species "Tectella patellaris (Fr.) Murr." and genus "Tectella Earle" is a first record for Korean fungal flora. Specimens cited here have been deposited in the Herbarium Conservation Center of National Academy of Agricultural Sciences.

• 한국과학교육학회지
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• 제24권2호
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• pp.309-319
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• 2004

이 연구는 학교 과학교육의 방향 설정을 위한 기초 연구로써, 학교 과학교육과 대표적인 사교육이라고 할 수 있는 학원 과학교육에 대한 중학생의 인식을 조사 분석하였다. 경기 지역 학원에서 과학 교과를 수강하는 중학생 180명을 대상으로, CES 축소형(Short form of classroom environment scale)을 사용하였다. 연구결과를 살펴보면, 첫째, 학생들은 과학학습의 보충, 학교 과학 수업에 대한 부정적인 생각, 학생들이 스스로 공부하는 방법이나 습관을 기르지 못해서 학원을 다니는 것으로 나타났다. 둘째, 학생들은 학교 과학 수업이 체계적으로 구성되어 있고 교사들이 과학 수업에 대한 준비를 철저히 하며, 학교 과학 수업 시간에 열심히 공부하는 것은 매우 중요하다고 인식하고 있었다. 그러나, 학교 과학 수업 시간보다는 학원 과학 수업시간에 더욱 열심히 참여하고 있는 것으로 나타났다. 셋째, 학생들은 교사가 자신들의 과학학습에 대하여 보다 실질적이고 구체적인 지원을 더 많이 해 주길 기대하고 있는 것으로 나타났다. 넷째, 학생들은 학교 과학 수업시간보다 학원 과학 수업시간에 질문하는 것이 더욱 편하고, 학원 과학 강사를 더욱 친근하게 인식하고 있는 것으로 조사되었다. 다섯째, 학생들은 학원이나 학교 과학 시간에 다루는 수업자료들이 재미없다고 생각하고 있었다.

• Mycobiology
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• 제50권5호
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• pp.389-398
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• 2022

Endophytic fungi are promising sources for the production of podophyllotoxin-an important anticancer compound, replacing depleted medical plants. In this study, the endophytes associated with Dysosma difformis-an ethnomedicinal plant species were isolated to explore novel sources of podophyllotoxin. Fifty-three endophytic fungi were isolated and identified by morphological observation and ITS-based rDNA sequencing, assigning them to 27 genera in 3 divisions. Fusarium was found the most prevalent genus with a colonization frequency of 11.11%, followed by Trametes (9.26%) and Penicillium (7.41%). Phylogenetic trees were constructed for the endophytic fungi community in two collection sites, Ha Giang and Lai Chau, revealing the adaptation of the species to the specific tissues and habitats. Cytotoxic activity of endophytic fungal extracts was investigated on cancer cell lines such as SK-LU-1, HL-60, and HepG2, demonstrating strong anti-cancer activity of six isolates belonging to Penicillium, Trametes, Purpureocillium, Aspergillus, and Ganoderma with IC₅₀ value of lower than 10 ㎍/mL. The presence of podophyllotoxin was indicated in Penicillium, Trametes, Aspergillus and for the first time in Purpureocillium and Ganoderma via high-performance liquid chromatography, which implied them as a potential source of this anticancer compound.

• Journal of Biosystems Engineering
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• 제36권2호
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• pp.140-146
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• 2011

This study was performed to develop a rapid test kit for pathogenic Salmonella in various samples. The rapid detection kit has been fabricated based on nitrocellulose lateral-flow strip. Colloidal gold and biotin conjugated Salmonella antibodies were used as a tag and a receptor, respectively. Manually spotted Salmonella antibody and Neutravidin on nitrocellulose membrane were used as test and control lines, respectively. Feasibility of the rapid kit to detect Salmonella typhimurium in samples were evaluated. The intensity of the color of the test line started to increase with the samples in which higher concentration of the cells were contained. The sensitivity of the sensor was $10^6$ cfu/mL Salmonella spiked in PBS. Also, the rapid test kit could detect $10^6$ cfu/mL of Salmonella in chicken meat extract.

• 식물병연구
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• 제17권2호
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• pp.232-234
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• 2011

During survey of postharvest diseases of vegetables in the middle region of Korea in 2003, 2004 and 2005, new disease symptoms showing watery rot and soft rot were observed. In this study, the disease causal agents were identified as Geotrichum candidum, and their host range and pathogenicity were investigated. G. candidum isolated had wide host range and strong pathogenicity against carrot, cucumber, tomato and pumpkin. The disease occurrence on several vegetables that G. candidum can be a serious threat to stable production of fresh vegetable.

• Journal of Plant Biotechnology
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• 제37권2호
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• pp.205-211
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• 2010

Yield productivity of staple crops must be increased at least 50% by 2050, in order to feed the world population which is expected to reach 90 billions. Photosynthetic carbon assimilation and carbohydrate metabolism leading to the production of starch would be the final frontier to quest for new sources of technology enabling such a drastic increase of crop productivity. In this review, attempts to genetically engineer plant photosynthetic carbon reduction cycle and metabolic pathways to increase starch production are introduced.

• The Plant Pathology Journal
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• 제26권4호
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• pp.417-420
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• 2010

The expression of HR-like lesion inducing gene of Oryza sativa (OsHRL) was slightly increased by Xanthomonas oryzae pv. oryzae (Xoo) infection. Transgenic rice plants over-expressing OsHRL gene were challenged with Xoo and the development of disease symptoms were examined to investigate the effect of OsHRL gene expression on plant defense responses. The over-expression of OsHRL increased disease resistance against Xoo compared with wild type plants.

• 한국유기농업학회지
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• 제19권spc호
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• pp.283-286
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• 2011

Powdery mildew and leaf mold were major diseases in organic cultured tomatoes. $NaHCO_3$ and $KH_2PO_4$ were selected as control agents for controlling tomato powdery mildew. Control effect of the selected control agents was increased when they were treated with oil-egg yolk mixtures (OEYO). Also four organic materials used commercially including copper hydroxide and sulfur, showed high control effect more than 90% in green house. Also two organic matters, copper hydroxide and sulfur showed high control effect in farmer's field. When tomatoes were cultivated in plastic house installed with circulation fan, incidence of powdery mildew and leaf mold was reduced by 56% and 60%, respectively.

• 한국유기농업학회지
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• 제19권spc호
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• pp.139-140
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• 2011

In organic farming agriculture, integration of cover crop into cropping system is recommended to improve the soil quality, prevent soil erosion, and control weeds. The aim of this study was to control weeds in soybean fields by integration of cover crops such as hairy vetch and rye. Due to cover crop mulching, weeds occurrence and growth were radically decreased. One month later after transplanting, weed growth inhibition rate of hairy vetch and rye treatment were 98% and 89% respectively, while crimson clover treatment were 50%. These effects last long over two month. The soybean yield of hairy vetch treatment was best. Therefore using hairy vetch as cover crop was highly recommended in organic soybean field.

• 한국유기농업학회지
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• 제19권spc호
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• pp.127-128
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• 2011

Vinegar has been considered as a potential organic herbicide, but more knowledge is needed about acetic acid concentration, application volume and use of adjutants on weed control. In this study, we determined optimum acetic acid concentration and spraying time on several weed species. Vinegar is more effective in broadleaf weeds than grasses. Vinegar is also effective in controlling younger weeds such as $3^{rd}$ to $4^{th}$ weeks after emergency. For example, $3^{rd}$ weeks after emergency weeds were easily controlled at 2-3% of vinegar solution. But $4^{th}$ weeks after emergency weeds were controlled at 4-5% of vinegar. Therefore vinegar concentration was recommended about 5%, and application time was when the weeds were young-within 3 leaf stage.