• 한국토양비료학회지
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• 제44권4호
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• pp.637-649
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• 2011

Soil microorganisms play a major role in improving soil fertility and plant health. Symbiotic arbuscular mycorrhizal fungi (AMF) form a key component of the soil microbial populations. AMF form a mutualistic association with the host plant and exert a positive influence on its growth and nutrient uptake. The establishment of mycorrhizal symbioses with the host plant can positively be influenced by plant growth promoting rhizobacteria through various mechanisms such as increased spore germination and hyphal permeability in plant roots. Though there are evidences that combined interactions between AMF and PGPR can promote the plant growth however mechanisms of these interactions are poorly understood. Better understanding of the interactions between AMF and other microorganisms is necessary for maintaining soil fertility and enhancing crop production. This paper reviews current knowledge concerning the interactions between AMF and PGPR with plants and discusses on enhanced nutrient availability, biocontrol, abiotic stress tolerance and phytoremediation in sustainable agriculture.

• 한국토양비료학회지
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• 제43권4호
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• pp.506-513
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• 2010

다양한 유기질비료 수준에서 Methylobacterium oryzae CBMB20의 처리가 고추의 생육촉진에 미치는 영향을 조사하였다. 유기질비료 권장시비수준의 70, 85, 100, 120% 시용구에서 시비량이 증가함에 따라 고추의 신장, 건물중 및 수량에서 유의성 있는 증가를 확인하였다. M. oryzae CBMB20의 접종 처리에서 고추의 생장이 증가하였으며, 고추의 수량 또한 각 유기질 비료 수준별로 10~35% 증가하였다. 수확기에 조사한 근권토양의 메탄올자화세균의 밀도는 M. oryzae CBMB20 처리구에서 2.51~2.63 log CFU $g^{-1}$ soil 이었으며, 미처리구에서는 1.0 log CFU $g^{-1}$ soil 이하로 나타났다. 따라서 접종한 M. oryzae CBMB20은 고추 작물 근권토양에 효과적으로 군집하였으며, 식물생장촉진 호르몬의 분비 등의 작용을 통한 작물생장촉진효과를 발휘한 것으로 판단된다. M. oryzae CBMB20을 접종하지 않은 경우에는 고추의 최대 생장과 수량이 유기질 비료 권장시비 수준 120%에서 나타났으나, M. oryzae CBMB20을 접종한 경우에는 최대 생장과 수량이 권장시비 수준에서 나타났다. 이러한 결과는 식물생장촉진미생물의 접종을 통하여 비료 사용량의 절감 가능성을 제시하는 것이며, 식물생장 촉진 미생물 제제로서 M. oryzae CBMB20의 활용이 가능하리라 사료된다.

• 한국융합학회논문지
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• 제9권8호
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• pp.219-224
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• 2018

여포 상피세포에 우수한 모발성장 촉진효과를 보이는 minoxidil의 단점을 보완하고자 대체의학제재로서의 모발 성장 촉진제로 지모를 연구하였다. 지모과(知母科)의 뿌리식물인 지모(知母)는 해열제, 항 당뇨병, 항우울제, 항염제 등으로 이용되고 있는 한국의 전통적인 약용식물이다. 지모 에탄올 추출물을 마우스의 등에 도포하여 관찰하였는데 모든 그룹의 마우스에서 체중과 음식 섭취량은 유의한 차이를 보이지 않았다. 지모 에탄올 추출물은 혈청 조성의 변화 없이 왕성한 모발성장 촉진효과를 보임으로써 향후 모발성장 촉진제로서 유용한 가치가 있으리라 사료된다.

• 미생물학회지
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• 제51권1호
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• pp.14-20
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• 2015

동해안에 자생하는 해안식물인 개질경이를 채집하였고, 뿌리로부터 형태적으로 다른 내생균류 20균주를 선발하였다. 개질경이 뿌리에 공생하는 내생균류의 ITS-rDNA 염기서열을 분석하였으며, 분리된 내생균류의 유연관계는 Bayesian 프로그램을 이용하여 계통분석을 하였다. 모든 내생균류의 농축배양여과액을 난장이벼에 처리하여 식물생장촉진활성을 스크리닝하였고, 분리된 균류 중에서 E/PC/10/1 균주가 생장촉진활성이 우수한 것으로 확인되었다. E/PC/10/1 균주의 배양여과액을 HPLC와 GC/MS-SIM을 이용하여 분석한 결과, 식물호르몬인 지베렐린 $GA_1$, $GA_3$, $GA_4$가 정량분석 되었다. 그리고 E/PC/10/1 균주의 명확한 동정을 위하여, beta-tubulin 유전자 염기서열을 이용한 분자적인 방법과 현미경을 이용한 형태적인 방법으로 동정하였다. 최종적으로 E/PC/10/1 균주는 GAs을 생산하는 새로운 P. spinulosum으로 동정되었다.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.96.1-96
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• 2003

Serratia plymuthim A21-4 strongly inhibits the mycelial growth, zoospore formation, and cystospore germination of Phytophthor spp and Pythium species. The bacterial isolate produced antifungal substance and chitinase. The bacteria also enhanced to plant growth remarkably in low nutritional condition. The application of cell suspension of A21-4 to pepper seedlings in greenhouse experiments and soil drenching in farmer's field was proved successfully to control the phythophthora blight of pepper. For the effective control, however, relatively high density of cell number(10$\^$9/cfu/$m\ell$) is required. Density effect was similar in plant growth promoting activity of A21-4. Though this investigation we improved the problem with changes of culture condition of bacteria and some nutritional amendment.

• The Plant Pathology Journal
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• 제17권6호
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• pp.366.1-366
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• 2001

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.101.2-102
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• 2003

The ability of P. chlororaphis O6 to induce resistance to Erwinia carotovora subsp. carotovara SCCI and to promote growth in tobacco was demonstrated in microtiter assays on plants pre-inoculated at the root level with the bacteria before challenge with the leaf pathogen. To identify th bacterial determinants involved in induced systemic resistance and plant growth promotion, cell culture of O6 grown in King's medium B was fractionated with organic solvents and purified using various columns. in vivo and in vitro assays with samples from successive fractionation steps of the O6 supernatant led to the conclusion that antibacterial compounds were observed in aqueous layer, and to the isolation of fractions containing metabolites that retained most of the resistance-inducing activity (70：30, methanol：water) and the plant growth promotion (80：20 and 90：10, methanol：water) after ODS column chromatography. Although these molecules remain to be purified further and structurally characterized, its isolation is an addition to the range of determinants from plant growth-promoting rhizobacteria known to stimulate plant defence.

• Mycobiology
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• 제29권1호
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• pp.48-53
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• 2001

Plants have the ability to acquire an enhanced level of resistance to pathogen attack after being exposed to specific biotic stimuli. To obtain plant growth-promoting rhizobacteria inducing resistance against cucumber anthracnose by Colletotrichum orbiculare, more than 800 strains of rhizobacteria were screened in the greenhouse. Among these strains, Bacillus amyloliquefaciens solate EXTN-1 showed significant disease control efficacy on the plants. Induction of pathogenesis-related(PR-la) gene expression by EXTN-1 was assessed using tobacco plants transformed with PR-1a::$\beta$-glucuronidase(GUS) construct. GUS activities of tobacco treated with EXTN-1 and salicylic acid-treated transgenic tobacco were significantly higher than those of tobacco plants with other treatments. Gene expression analyses indicated that EXTN-1 induces the accumulation of defense-related genes of tobacco. The results showed that some defense genes are expressed by the treatment with EXTN-1 suggesting the similar resistance mechanism by salicylic acid.

• Journal of Microbiology and Biotechnology
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• 제22권6호
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• pp.763-770
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• 2012

Pseudomonas fluorescens 2112, isolated in Korea as an indigenous antagonistic bacteria, can produce 2,4-diacetylphloroglucinol (2,4-DAPG) and the siderophore pyoveridin2112 for the control of phytophthora blight of red-pepper. P. fluorescens 2112 was classified into a new genotype C among the 17 genotypes of 2,4-DAPG producers, by phlD restriction fragment length polymorphism (RFLP). The colonizing ability of P. fluorescens 2112 in pea rhizosphere was equal to the well-known pea colonizers, P. fluorescens Q8r1 (genotype D) and MVP1-4 (genotype P), after 6 cycling cultivations for 18 weeks. Four tested 2,4-DAPG-producing Pseudomonas spp. could colonize with about a 96% dominance ratio against total bacteria in pea rhizosphere. The strain P. fluorescens 2112 was as good a colonizer as other Pseudomonas spp. genotypes in pea plant growth-promoting rhizobacteria.

• Journal of Microbiology and Biotechnology
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• 제17권1호
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• pp.96-103
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• 2007

Plant growth-promoting rhizobacteria (PGPR) have the potential to be used as microbial inoculants to reduce disease incidence and severity and to increase crop yield. Some of the PGPR have been reported to be able to enter plant tissues and establish endophytic populations. Here, we demonstrated an approach to screen bacterial endophytes that have the capacity to promote the growth of pepper seedlings and protect pepper plants against a bacterial pathogen. Initially, out of 150 bacterial isolates collected from healthy stems of peppers cultivated in the Chungcheong and Gyeongsang provinces of Korea, 23 putative endophytic isolates that were considered to be predominating and representative of each pepper sample were selected. By phenotypic characterization and partial 16S rDNA sequence analysis, the isolates were identified as species of Ochrobacterium, Pantoea, Pseudomonas, Sphingomonas, Janthinobacterium, Ralstonia, Arthrobacter, Clavibacter, Sporosarcina, Acidovorax, and Brevundimonas. Among them, two isolates, PS4 and PS27, were selected because they showed consistent colonizing capacity in pepper stems at the levels of $10^6-10^7CFU/g$ tissue, and were found to be most closely related to Pseudomonas rhodesiae and Pantoea ananatis, respectively, by additional analyses of their entire 16S rDNA sequences. Drenching application of the two strains on the pepper seedlings promoted significant growth of peppers, enhancing their root fresh weight by 73.9% and 41.5%, respectively. The two strains also elicited induced systemic resistance of plants against Xanthomonas axonopodis pv. vesicatoria.