• The Korean Journal of Mycology
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• v.19 no.3
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• pp.231-237
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• 1991

This study was conducted in order to find out biological control of sesame wilt and blight caused by Fusarium of oxysporum f. sp. vasinfectum and Phytophthora nicotianae var. parasitica by using Streptomyces spp. Two sesame pathogens, Fusarium oxysporum f. sp. vasinfectum and Phytophthora nicotianae var. parasitica were purely isolated from diseased sesame plants of the field. Streptomyces species were isolated from 72 soil samples collected from red pepper and sesame uplands in Chungbuk and selected as antagonists according to the results of dual culture. The selected Streptomyces isolates such as St-11 and St-20 were confirmed their antagonistic effect through mycelial inhibition zone and inhibitory effects on the mycelial growth of the pathogens by culture filterate of the antagonists. Inhibitory effects on the conidial germination of Fusarium oxysporum vasinfectum and Phytophthora nicotianae parasitica by the antagonists were also tested in addition to mycelial Iysis. The antagonists St-11 and St-20 showed inhibitory effect on growth of sesame seedlings after seeds soaked in the suspension. Effect of soil inoculation with antagonist St-11 showed 40 to 78 percent of control effect for two diseases in comparison with control under greenhouse.

• Microbiology and Biotechnology Letters
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• v.14 no.2
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• pp.187-192
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• 1986

The inoculation effect of the highly nitrogen fixing strains of R. japonicum were tested in the 3 kinds of soil with different cultural history onto Gycine max cv. Jang-yeob. The nodulation and nitrogen fixation activity in 3 test soils all showed the great increase in inoculated group compared to the non-inoculated group. The plant dry weight of the in-oculated groups were increased about 10% than that of the non-inoculated groups. The numerical index of the increase in total nitrogen fixation activity were 238% in the pre-cultivated, 266% in the immatured and 157% in the matured soil and these results suggested the clear effect of inoculation. Among the strains tested, R. japonicum R214 and Rl38 showed the excellent inoculation effect.

• The Korean Journal of Pesticide Science
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• v.13 no.3
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• pp.165-170
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• 2009

Insecticidal efficacies of plant extracts and environmental friendly agro-materials against green peach aphids, two spotted spider mites, and diamondback moths were evaluated in the lab condition. Oxymatrine and matrine, derivatives of Sophora flavescens, were effective to all three tested pest insect species. Selected environmental friendly agro-materials available from the market mainly contained active ingredients of nicotine, azadirachtin, and matrine were all effective to control green peach aphids and two spotted spider mites.

• Korean journal of applied entomology
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• v.7
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• pp.77-81
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• 1969

The effects of submerged method. Zentmyer's drench method. pot test and field test with materials such as Carbamisol (ammonium methyldithiocarbamic acid $30\%$), NCS (ammonium N-methyldithiocarbamate$50\%$, Similuton(ethyl phenethynylmeroury $3.3\%$), Soill(N-ethylmercuric p-toluensulfonanilide $4\%$, Captan (N-trichloromethylthio-1, 2, 3, 6-tetra-hydrophthalimide $80\%$), Difolatan(N-tetrachloroet-hylthio 4cyelohexeno-1,2-dicarboximide $80\%$, Grand(2, 3-dibromepropionitryl $20\%$, trichloronitroethylene $20\%$) and Calcium hydroxide upon occurrence of Fusarium wilt of cucumber were studied. The results are summarized as follows. 1. According to submerged method, all the compounds tested were highly inhibitory to mycelial growth of Fusarium oxysporum f. cucumerinum except calcium hydroxide. But several compounds were no inhibitory to the causal fungus except Grand and Similuton, with Zentmyer's drench method. 2. Grand was the most effective fungicide for the control of cocumber Fusarium wilt in the pot test, and followed by Similuton and calcium hydroxide. The population of Fusarium oxysporm was markedly reduced when soil was treat with Grand compared with other chemicals. 3. Fungicidal effects upon occurrence of Fusarium wilt of cucumber under the field experiment varied with the fungicides. Of the fungicides tested. Grand gave the best control, and followed by Difolatan.

• Journal of the Korean Geotechnical Society
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• v.29 no.2
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• pp.65-73
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• 2013

The purpose of this study is to confirm strength and effectiveness of grouting of the sand treated with bacteria. In order to analyze the cementation of sand treated with bacteria, five types of specimens(Not treated, Cement 2% treatment, Cement 4% treatment, Cement 2% + $CaCO_3$ 2% treatment and $CaCO_3$ 4% treatment) were made. Unconfined compressive strength tests were done on $D\;5cm{\times}H\;10cm$ specimens and biogrouting tests were performed on $D\;6cm{\times}H\;12cm$ specimens to observe the effectiveness of grouting with bacteria. As a result, Cement 2% + $CaCO_3$ 2% treatment was found to be the most effective in terms of the unconfined compressive strength.

• Journal of the Korea institute for structural maintenance and inspection
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• v.12 no.1
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• pp.193-202
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• 2008

This paper investigates experimentally the confining effect, strengthening capacity and rebound rate of sprayed Fiber-Reinforced-Polymer (SFRP). From the method, resin and chopped fibers are sprayed separately from the nozzle with high pressure, and then they are attached to the concrete surface, so structure could be repaired. To evaluate the strengthening effect of sprayed FRP, cylindrical specimens and beam specimens were strengthening with SFRP. As main material of FRP, glass fiber and polyester resin are used. To investigate the optimum condition of sprayed FRP, the effects of fiber length, coating thickness, fiber volume ratio and concrete strength were examined. Capacities of sprayed FRP method were also compared to the FRP sheet method. In case of the sprayed FRP, rebound rate is important parameter considering economical efficiency and constructibility, so rebound rate of was discussed. From the test results, optimum conditions of sprayed FRP were determined. SFRP method showed superior strengthening capacities than FRP sheet method.

• Journal of the Korean GEO-environmental Society
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• v.11 no.12
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• pp.57-62
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• 2010

In this study, the effect of different silt contents on the shear characteristics of silty sands was evaluated. Two series of triaxial compression tests were performed on the cylindrical specimens of compacted Nakdong river sand with 10% and 30% silt contents under unconsolidated undrained condition. All identical specimens were prepared to compact with same initial water content for five layers and saturated using control panel and then sheared under initial effective confining pressure, 100 to 400kPa. All specimens exhibited a strain softening tendency after failure in stress-strain curves and deviator stresses of specimens with 10% silt content were greater than those of specimens with 30% silt content. Pore water pressures of specimens with 10% silt content were observed negative(i.e. swelling) due to increasing void ratio after failure but those of specimens with 30% silt content were shown only positive. The behavior of compacted cylindrical specimens with low silt content was more dilative than that of high silt content. Peak deviator stresses decreased as increasing silt content and peak pore water pressures increased as increasing silt content.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.20
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• pp.27-62
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• 1975

These studies were aimed at clarifying whether or not selecting agronomic characteristics of hybrid-rice populations under greenhouse conditions was useful. The selection of two quantitative characteristics, culm length and heading date, and two qualitative characteristics, shattering and awnedness, was very effective, but the flag leaf length and the exsertion of panicle was not consistent, varying from one cross to another.

• Korean Journal of Soil Science and Fertilizer
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• v.25 no.1
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• pp.99-107
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• 1992

Effects of the indigenous Vesicular-arbuscular mycurrhizal fungi(VAMF) on early growth response of greenhouse grown crops were experimented. This study was done to evaluate the benefit of indigenous VAMF inoculation on the early growth and the subsequent growth after transplanting of some crops such as cucumber, tomato, hot pepper, eggplant, and melon. Leaf area, shoot dry weight, and plant length of mycorrhizal greenhouse crops showed the tendency of significant or no significant increase over control plants receiving no inoculation. The levels of VA mycorrhizal colonization were increased with plant growth, and infection rates of horticultural crop except hot pepper around one week after transplanting were decreased, while that of 8 weeks after emergence of mycorrhizal seedlings were increased again and infected by around 50% at harvesting time. In spore densities in the rhizosphere soil of craps experimented, the number of spore ranged from $72.7{\pm}26.3$ to $100{\pm}10.3g^1$ on dried soil basis and high density showed in both cucumber and tomato. Total nitrogen contents in shoots were lower in the mycorrhizal plants than non-mycorrhizal one, whereas P uptake in mycorrhizal hot pepper and tomato were highly ramarkable. The K contents in the shoots of mycorrhizal cucumber and eggplent were highly enhanced. Inoculation of the indigenous VAMF enhanced shoot Ca and Mg in both tomoto and melon. The contents of Fe, Zn, Mn and Cu in shoots of mycorrhizal crops were higher than non-mycorrhizal plants and vice versa in case of eggplent. Inoculation of the indigenous VAMF to horticultural crops were effective for alleviation of transplanting shock, and pretransplanting infection improved subsequent growth by reducing the time required for establishment of a functional mycorrhizal symbiosis following transplanting.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2004.05a
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• pp.135-137
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• 2004

유산균을 첨가한 발효육의 지방산패도를 측정하여 EM의 항산화 효과와의 관련성을 살펴보기 위해 실험을 실시하였다. 발효육의 생산에 사용된 Lactobacillus casei KCTC 3109 공시균주는 한국생명공학연구원 유전자지원센터 한국유전자은행에서 주문 구입하였다. 실험에 사용된 돈육은 도살 후, $4^{\circ}C$ 냉장고에 저장하였던 랜드레이스의 대퇴부 육을 사용하였다. 발효육의 항산화 정도를 알아보기 위해 TBA 방법으로 실험하였다. 대조구는 저장 0일부터 저장 3일까지 TBARS 치가 지속적으로 상승하는 것을 보였다. 그러나 저장 4일째부터는 TBARS 치가 감소하는 것을 볼 수 있다. 반면, 유산균을 첨가한 육에서는 저장 0일째부터 2일째까지는 약간 TBARS 값이 증가하였으나 저장 3일째는 가장 낮은 수치를 보였다. 그러나 저장 4일째부터는 TBARS 치가 점차적으로 증가하였다. 대조구의 저장 3일째의 TBARS치가 0.19 mgMDA/Kg을 나타낸 반면, 유산균을 첨가하여 $37^{\circ}C$에서 3일간 정치 배양한 발효육의 TBARS치는 0.02 mgMDA/Kg을 나타내 8배 정도의 항산화 효과를 나타냈다. 결론적으로 유산균 자체가 항산화 효과가 있음을 알게 되었고 EM의 항산화 효과에도 영향을 주는 것으로 사료된다.