• KSBB Journal
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• 제24권4호
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• pp.334-340
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• 2009

식물성장 촉진 기능을 가지는 PGPR (plant growth-promoting rhizobacteria)균은 특수한 토양시료를 사용하여 내열성을 가지는 400개의 균주를 분리하였다. 이들 분리균주에서 선발한 공시균주 Bacillus sp. YK-5는 항진균성 물질을 생산하였으며, 시험균주 Asp. flavus를 대상으로 생산조건을 검토한 결과, 공시균주의 생육배지는 생육촉진효과와 식물병원균에 대한 방제를 위해 1% peptone 및 yeast extract, 5% black sugar가 함유된 modified LB배지를 사용하였다. 식물병원균에 대한 공시균주의 길항효과는 시험균주인 식물병원균 Fusarium oxysporum KACC 40052균에 대해 배양 7일째까지 강한 생육저해를 보였다. 공시균의 식물성장촉진능은 궁중무 및 벼를 대상으로 pot 실험한 결과, 궁중무의 경우 경엽수, 줄기의 길이 및 뿌리의 길이가 무처리구에 비해 약 60%이상 우수한 성장촉진효과를 나타내었으며, 벼의 경우 이식 후 시비 8일째 시판제품 처리구에 비해 공시균주 처리구는 잎의 길이와 흰 세근의 발달이 우수하여 뿌리의 발육에 현저한 생육촉진 효과를 나타내었다. 공시균주의 동정은 분자계통분류학적 분석 (형태, 배양, 생리, 화학적 및 분자생태학적 측면)에 의해 B. subtilis YK-5로 명명하였다.

• 농약과학회지
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• 제13권4호
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• pp.262-266
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• 2009

유채 근권으로 부터 분리된 고활성 근권균 Burkholderia pyrrocinia 13-1는 유채의 생육을 촉진 시키며 특히 저온조건에서의 식물 생육이 우수하다. 이 균주의 유채 처리는 저온조건에서 뿌리의 발근을 좋게 하며 지상부 생육도 다른 대조 균주처리 보다 우수하다. 근권미생물이 가지는 유용 기능 중 식물의 영양 흡수와 병 저항성에 관여하는 시드로포어의 생성, 항균활성과 토양 중 불용화 인산인 칼슘포스페이트를 가용화시켜 식물의 흡수를 돕는 용해 능력이 우수하였다. 이와 같은 특성은 식물의 생육을 촉진시키는 근권세균의 활성기작으로 식물생육 촉진용으로 유채재배에 적용할 수 있을 것으로 기대된다.

• 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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• 제28권6호
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• pp.938-945
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• 2018

Salinity stress is an important environmental problem that adversely affects crop production by reducing plant growth. The impacts of rhizobacterial strains to alleviate salinity stress on the germination of Lactuca sativa and Raphanus sativus seeds were assessed using different concentrations of NaCl. Plant growth-promoting rhizobacteria (PGPR) strains were also examined to improve the early germination of Chinese cabbage seeds under normal conditions. Lactobacillus sp. and P. putida inoculation showed higher radicle lengths compared with non-inoculated radish (Raphanus sativus) seeds. LAP mix inoculation increased the radicle length of lettuce (Lactuca sativa) seedlings by 2.0 and 0.5 cm at salinity stress of 50 and 100 mM NaCl concentration, respectively. Inoculation by Azotobacter chroococcum significantly increased the plumule and radicle lengths of germinated seeds compared with non-inoculated control. A. chroococcum increased the radicle length relative to the uninoculated seeds by 4.0, 1.0, and 1.5 cm at 50, 100, and 150 mM NaCl concentration, respectively. LAP mix inoculation significantly improved the radicle length in germinated radish seeds by 7.5, 1.3, 1.2, and 0.6 cm under salinity stress of 50, 100, 150, and 200 mM NaCl concentration, respectively. These results of this study showed that PGPR could be helpful to mitigate the salinity stress of different plants at the time of germination.

• KSBB Journal
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• 제31권1호
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• pp.58-65
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• 2016

In this study, Arthrobacter scleromae SYE-3, which was isolated from indigenous plant in a subtropical region, Neigeria, with plant growth promoting activity was evaluated to determine the optimal culture condition. A bacterial strain SYE-3 had the IAA productivity ($89.15{\pm}0.36mg/L$) and ACC deaminase activity ($0.20{\pm}0.06$ at 72 hours). Also, optimal culture conditions such as temperature and pH of strain SYE-3 were $20^{\circ}C$ and 10 in LB medium, respectively. Strain SYE-3 had up to 3% salt tolerance in the LB medium. Plant growth promoting ability of strain SYE-3 using yam (Dioscorea japonica Thunb.) was evaluated. As a result, strain SYE-3 had showed very powerful effect on the increase of the shoot length and root biomass of yam (190.0% and 282.41% increase for 112 days, respectively). These results indicated that Arthrobacter scleromae SYE-3 can serve as a promising microbial resource for the biofertilizers of subtropical crops.

• 생명과학회지
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• 제31권7호
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• pp.641-653
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• 2021

본 연구에서는 근권토양으로부터 18종의 세균을 순수분리하고, 이들의 식물 병원성 진균 생육억제 활성, 식물생장촉진 활성 및 미네랄 가용화능을 평가하였다. Bacillus 속과 Pseudomonas 속 분리균주의 항진균 활성을 통해 생물학적 방제제로서의 가능성을 확인할 수 있었으며, 이는 식물 병원성 진균의 세포벽에 작용하는 여러 가수분해효소 활성과 siderophore 생성능 등에 기인된 것으로 판단된다. 또한 대부분의 분리균주가 aminocyclopropane-1-carboxylate deaminase 생성능, indole-3-acetic acid 생성능 및 질소 고정능을 갖고 있는 것으로 나타났으며, 이러한 특성은 식물이 흔히 노출될 수 있는 환경 스트레스 조건 하에서 스트레스 에틸렌의 농도를 감소시킴으로써 뿌리 발달 및 성장, 그리고 작물의 생산성에 긍정적인 영향을 줄 것으로 판단된다. 그리고 분리균주의 인산, 규소, 탄산칼슘, 아연 가용화능 등을 확인한 결과, 일부 분리균주들의 미네랄 가용화능을 확인하였으며, 이들 분리균주를 식물 생장 시에 접종한다면 식물 생장에 필요한 영양분을 식물이 흡수할 수 있는 이용가능한 형태로 변환시켜 식물의 생장에 도움을 줄 수 있을 것으로 기대된다. 이러한 항진균 활성, 식물생장촉진 활성 및 미네랄 가용화능의 결과를 통해 분리균주 18종의 biocontrol agent로서의 이용가능성을 제시하고자 한다.

• 한국토양비료학회지
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• 제45권4호
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• pp.582-592
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• 2012

Microorganisms present in the rhizosphere soil plays a vital role in improving the plant growth and soil fertility. Many kinds of fertilizers including chemical and organic has been approached to improve the productivity. Though some of them showed significant improvement in yield, they failed to maintain the soil properties. Rather they negatively affected soil eventually, the land became unsuitable for agricultural. To overcome these problems, microorganisms have been used as effective alternative. For past few decades, plant growth promoting rhizobacteria (PGPR) and arbuscular mycorrhizal fungi (AMF) have been used as effective inoculants to enhance the plant growth and productivity. PGPR improves the plant growth and helps the plant to withstand biotic and abiotic stresses. AM fungi are known to colonize roots of plants and they increase the plant nutrient uptake. Spore associated bacteria (SAB) are attached to spore wall or hyphae and known to increase the AMF germination and root colonization but their mechanism of interaction is poorly known. Better understanding the interactions among AMF, SAB and PGPR are necessary to enhance the quality of inoculants as a biofertilizers. In this paper, current knowledge about the interactions between fungi and bacteria are reviewed and discussed about AMF spore associated bacteria.

• Journal of Applied Biological Chemistry
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• 제62권3호
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• pp.247-250
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• 2019

Wheat is one of the most important grains. Its consumption is increasing globally. Many countries are making efforts to increase the extent of wheat harvest. It is known that plant growth promoting rhizobacteria (PGPRs) have beneficial effects on various plants. Two PGPRs including Paenibacillus pabuli strain P7S (PP7S) and Pseudomonas nitroreducens strain IHB (PnIHB) were employed to investigate effects of PGPRs on early growth of three wheat cultivars (Koso, Seakumkang, and Jokyung). While PP7S had adverse effects on Seakumkang and Jokyung, PP7S had positive effects on Koso except root length compared to control group having no treatment of PP7S. However, all treatments with PnIHB had adverse effects on germination rate, root/shoot lengths, vigor index, and dry root/shoot weights of all three wheat cultivars. These positive effects with PP7S on Koso might be related to the earlier emergence of wheat seed above soil which is known to be an indicator of increased yield. Results of the present study suggest that if proper PGPR strains are selected, they could have positive effects on early growth rate of a wheat cultivar.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2003년도 제10차 국제학술회의 및 추계정기 학술발표회
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• pp.45-45
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• 2003

The aim of the present study was to assess the importance of siderophore producing rhizobacteria on the growth of Brassica juncea under chromium stress. Pseudomonas sp. (A4) produced an iron chelating substance siderophores in iron deficient medium. Under chromium stress condition Pseudomonassp. (A4) markedly increased the root and shoot length and also biomass of Brassica juncea as compared to Pseudomonas sp. (A3). This plantgrowth promotion has been related to the microbial production of siderophore.

• The Plant Pathology Journal
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• 제21권3호
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• pp.244-251
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• 2005

The induction of growth promotion on numerous crops by rhizobacteria is a well documented phenomenon. In case of tomato (Lycopersicon esculentum), fruit yield is higher in replant soil than that in fresh soil. To investigate what kind of rhizobacterium is involved, microbial community in rhizosphere and on rhizoplane of tomato plants from each soil was analyzed by dilution plating on selective media. Many Gram-negative bacteria and actinomycetes were isolated from tomato in replant soil. One Gram-negative rhizobacterium isolated was identified as Pseudomonas putida based on its biochemical characteristics, fatty acid methyl ester analysis and 16S rDNA sequence. This bacterium designated strain 17 inhibited the growth of Pseudomonas corrugata, and increased growth of tomato seedlings. In addition, its culture filtrate inhibited conidial germination of plant-pathogenic fungi such as Fusarium oxysporum f. sp. radicis-lycopersici, F. oxysporum f. sp. cucumerinum, and Nectria radicicola. Scanning electron microscopy revealed strain 17 colonized and persisted on the epidermal surfaces of tomato radicles and roots. These results suggest that P. putida strain 17 may serve as a biological control agent to suppress multiple soil-borne diseases for tomato plants. Increased microbial populations that suppress deleterious microorganisms including pathogens could be one of the major factors in increased tomato yield in replant soil.