• Mycobiology
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• v.38 no.2
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• pp.156-158
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• 2010

Stem rot disease was found in garlic (Allium sativum L.) cultivated from 2008 to 2010 in the vegetable gardens of some farmers in Geumsan-myon, Jinju City, Gyeongnam province in Korea. The initial symptoms of the disease were typical water-soaked spots, which progressed to rotting, wilting, blighting, and eventually death. White mycelial mats had spread over the lesions near the soil line, and sclerotia had formed over the mycelial mats on the stem. The sclerotia were globoid in shape, 1~3 mm in size, and tan to brown in color. The optimum temperature for growth and sclerotia formation on potato dextrose agar (PDA) medium was $30^{\circ}C$. The diameter of the hyphae ranged from approximately 4 to $8\;{\mu}m$. Typical clamp connection structures were observed in the hyphae of the fungus, which was grown on PDA medium for 4 days. On the basis of the mycological characteristics and pathogenicity of the fungus on the host plants, the causal agent was identified as Sclerotium rolfsii Saccardo. This is the first report of stem rot disease in garlic caused by S. rolfsii in Korea.

• Korean Journal of Medicinal Crop Science
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• v.21 no.5
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• pp.348-352
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• 2013

This study was carried out to investigate the effect of sucrose, boric acid, and calcium nitrate in optimum pH and relative humidity on pollen germination and pollen tube growth of boxthorn (Lycium chinense M.). Medium containing 100mg/L of $H_3BO_3$ showed maximum pollen germination and pollen tube elongation, 64.8% and $920{\mu}m$. Additionally supplied calcium nitrate to the medium lowered pollen germination rate and pollen tube elongation. Here we report the optimum conditions for the pollen germination and pollen tube development was observed at 10% sucrose, 1.0% agar, pH 6.0, and 100% relative humidity.

• Educational Technology International
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• v.10 no.1
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• pp.59-78
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• 2009

Language Capital is one of the most important academic abilities and competencies for new era of globalization worldwide. In Europe and Asia where English is not the native language, it is necessary to encourage higher education to improve language competency from both qualitative and quantitative aspects. In so far as online university concerned, it appears of significance to prepare for globalization from the perspective of cross border education, and it needs to focus on how to design and develop English-medium teaching (EMT) or in other words English mediated instruction(EMI) for both teachers and students. In order to provide supportive programs of English-mediated class for teachers and students, the study examined and analyzed what abilities are needed for teachers based on DACUUM approach, suggesting teachers' competency as well as strategies for online- EMT. Based on literature review, DACUUM analysis, focus group interview with teachers and students who experienced online EMT, online programs supporting both teachers and students for online EMI were developed. This program expects to play roles of practical guidelines and reference for both teachers and students online in an extension of language capital improvement.

• Journal of Mushroom
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• v.14 no.4
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• pp.211-214
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• 2016

Geoni, a new variety of Auricularia polytricha, was bred in JARES(Jeollanamdo Agricultural Research and Extension Services) in 2012. Geoni was selected through the monospore hybridization with JNM21008 and JNM21014 in 2010. Based on a performance test conducted from 2011 to 2012, the Geoni was selected from a line showing an excellent light brown pileus and strong pest resistance. Geoni has a favorable chewiness, light brown and smooth pileus. In addition, Geoni was rich in dietary fiber. MCM(mushroom complete medium), Malt and PDA(Potato Dextrose Agar) mediums were suitable for cultivating the Geoni. The number of effective stipes was 39 ea/0.9 kg and minor axis and major axis of pileus were 6.9 cm and 8.7 cm respectively. The yield of Geoni was 291 g/0.9 kg in plastic bag. Geoni was required 40~54 days for culture at $20^{\circ}C$ and 24days for the primordia and growth period, which is longer than that of the control(Pung-un). Somatic incompatibility was formed between parental strains and Geoni. Analysis of the genetic diversity of the new variety "Geoni"revealed a different profile from the parental strains when RAPD(random Amplified Polymorphic DNA) primers were used.

• Weed & Turfgrass Science
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• v.6 no.4
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• pp.333-344
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• 2017

This study was conducted to examine the effect of cool-season grass overseeding on the green period, turf quality and density in zoysiagrass lawn. Treatments were perennial ryegrass (PR) overseeding ($60g\;m^{-2}$) on medium-leaf type zoysiagrass, Kentucky bluegrass (KB) overseeding ($20g\;m^{-2}$) on medium-leaf type zoysiagrass and narrow-leaf type zoysiagrass, and no overseeding on medium-leaf type zoysiagrass. Overseeding of KB or PR effectively provided quality improvement of zoysiagrass lawn by extending green-period about one month in spring and two months in fall season. PR overseeding showed quick green cover within 2-3 weeks but decreased the quality of overseeded zoysiagrass lawn during the summer season. Whereas, KB overseeding showed slow green cover taking two to three month after seeding but provided stable and good turf quality throughout the years. KB or PR overseeding significantly increased the turf density of zoysiagrass lawn except the period of summer depression of PR. The ground coverage of cool-season grasses ranged from 30 to 80% with considerable seasonal variation. As a result, KB and PR have their strengths and weaknesses as an overseeding material. Thus, the use of KB and PR as a mixture would provide better overseeding performance in zoysiagrass lawn.

• Journal of Mushroom
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• v.7 no.3
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• pp.105-109
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• 2009

Ten to thirty percent of ginko leaf pomace(GLP) were added to pine sawdust to investigate mycelial growth. Mycelial growth on the medium with GLP was 86~101(mm/28 days) and was slower than that of the control without GLP as, 102(mm/28 days). Mycelial growth time on medium of sawdust with 10 to 20% GLP was similar to the control without GLP as 29 days but that on medium with 30% GLP was delayed for 2 days. The time of pinhead formations of sawdust with 10 to 20% GLP was 7 days, the growth time to harvest was 11 days. These results were similar to those of the control without GLP. The sizes of pileus of treatments with 10 to 30% GLP were tend to be smaller compared with the control. The length of stipe of 10% GLP treatment was 98mm which was longer than that of the control with 91mm. The thickness of stipes of 10 to 30% GLP treatments were 45 to 48mm which were tend to be thicker than that of the control with 45mm. The hardness of stipe were 35,062($g/cm^2$) to 4,1065($g/cm^2$)) which were harder than that of the control with 32,156($g/cm^2$)). GLP treatments seem to be favorable to store or distribute. Yields per volume of GLP added treatments were 88.7g to 95.6g, which was increased 3 to 12% compare to 85.8g of the control without GLP.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2007.05a
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• pp.253-256
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• 2007

• Mycobiology
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• v.37 no.3
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• pp.218-224
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• 2009

The principal objective of this study was to determine the optimal liquid culture conditions in shake flasks for maximal sporulation of Beauveria bassiana. The optimal initial pH for the spore production of B. bassiana using Potato Dextrose Broth was 5.2. The screening in shake flasks of carbon and nitrogen sources resulted in the identification of an optimal medium based on 3% sucrose and 1% casamino acid, with a C : N ratio of 22 : 4. Using this medium, a production level of $5.65{\times}10^7$ spores per ml was obtained after 5 days of culture. Using 3% corn meal, 2% corn steep powder, and 2% rice bran, the maximum spore concentration of $8.54{\times}10^8$/ml was achieved 8 days after inoculation at $25^{\circ}C$ in a rotary shaking incubator operated at 200 rpm. This represents a yield gain of approximately 2.89 times that of pre-optimization.

• Horticultural Science & Technology
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• v.35 no.1
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• pp.30-37
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• 2017

This study was conducted to determine the effects of various growth substrates on the growth and flowering of hydroponically grown Freesia hybrid 'Gold Rich'. Perlite, peat moss and a perlite: peat moss mixture (1 : 1 ratio, v / v) were used as the growing media. The greatest plant height before flower bud differentiation was attained using mixed medium compared to the others. The type of medium used did not influence leaf number, mineral content or SPAD value in leaves. Flowering began at 137 days after planting in mixed medium, which was 13 days earlier than in perlite medium. The whole plant fresh weight was 21.3 g heavier in mixed medium than in perlite medium (40.9 g). A similar result was obtained for shoot length, with the highest value (96.6 cm) obtained in mixed medium, i.e., 20 cm higher than in perlite medium (76.6 cm). Floret number per plant was also the highest in mixed medium (14.4), i.e., 1.7 - times higher than in perlite medium. Therefore, among the substrates tested in this experiment, we recommend using mixed perlite: peat moss medium (1 : 1 ratio, v / v) for hydroponic culture of freesia, as the use of this medium improved the physical properties of the plants, producing the best results in terms of plant growth and cut-flower quality.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.10a
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• pp.38-38
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• 2018

최근 호두 기내 소비량은 급증하나 대부분 실생묘로 조림되어 결실까지 장기간 소요되며, 무성 번식률이 낮아 보급확대가 어렵다. 본 연구는 호두나무 관행 묘목 번식법 개선이 가능한 우량 국산묘 대량증식 기술 개발로 최적 배양조건을 구명하고자 수행하였디. 호두나무 등 목본류는 식물 조직배양 기본배지에서 산화방지제를 첨가하여 사용하는 경우, 배양체에서 생기는 페놀 화합물(Phenolic compound)의 작용을 억제하여 배양 식물체의 갈변(Browning) 또는 흑변(Blackening) 현상을 감소시키는 효과가 있다. 페놀 추출물은 배지로 빠져나와 갈변시키며 생존율을 저하시키는 원인이 되고 이를 제거하는 산화방지제는 배양 식물체의 생산효율을 높이는 효과를 나타내는 강력한 항산화제(Antioxidant) 역할을 한다. 호두나무의 액아를 배양하게 되면 조직 및 배지의 갈변화가 심하게 일어나는데, 휴면 정도가 깊을 수록 정단에서 추출되는 페놀성 물질의 함량이 증가하며, 식물 조직 내 페놀성 물질의 함량 정도와 배양의 고사율과는 상관관계가 있다. 이러한 식물 배양체에서 생기는 페놀 화합물에 의해 발생되는 배양상의 문제점을 해결하기 위하여 계대배양을 자주해 주거나 활성탄(Activated charcoal), Ascorbic Acid 등의 첨가물을 배지에 추가하는 방법이 있다. 이에 따라 호두 '신령' 품종의 액아배양의 페놀집적을 제거하기 위해 배지 내에 산화방지제 첨가물질 등을 농도별로 처리하였다. 호두나무 액아 배양 후 8주차 산화화방지제 첨가물질의 농도별 처리 효과는 생존율은 85.3%를 보였으며, 신초 형성율 76.4%, 신초수 1.9개/주, 신초장 27mm/주의 양호한 결과를 나타냈으며, 페놀 제거 및 유식물체 고사 억제 효과를 보였다.