• The Plant Pathology Journal
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• 제37권3호
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• pp.307-314
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• 2021

Pepper (Capsicum annuum L.) is an important agricultural crop worldwide. Recently, Colletotrichum scovillei, a member of the C. acutatum species complex, was reported to be the dominant pathogen causing pepper anthracnose disease in South Korea. In the present study, we isolated bacterial strains from rhizosphere soil in a pepper field in Gangwon Province, Korea, and assessed their antifungal ability against C. scovillei strain KC05. Among these strains, a strain named BS1 significantly inhibited mycelial growth, appressorium formation, and disease development of C. scovillei. By combined sequence analysis using 16S rRNA and partial gyrA sequences, strain BS1 was identified as Bacillus velezensis, a member of the B. subtilis species complex. BS1 produced hydrolytic enzymes (cellulase and protease) and iron-chelating siderophores. It also promoted chili pepper (cv. Nockwang) seedling growth compared with untreated plants. The study concluded that B. velezensis BS1 has good potential as a biocontrol agent of anthracnose disease in chili pepper caused by C. scovillei.

• 한국유기농업학회지
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• 제7권1호
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• pp.129-135
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• 1998

암면경, 펄라이트경 및 코코피트경 토마토의 생장촉진에 미치는 근권세균류의 영향을 구명하기 위하여 $Azospirilham\;sp.(4.5{\times}10^7cells/g),\;Rhodopseudomonas\;sp.(5.8{\times}10^5cells/g),\;Pseudomonas\;sp.(6.1{\times}10^6cells/g$) 및 Bacillus sp. 와 Corynebacterium glutamicum의 융합체($9.1{\times}10^5cells/g$) 등의 군주를 근권에 처리하였다. 군주의 근권처리시 토마토의 전반적인 생장이 대조구에 비해서 촉진되었으며, 식물생장촉진효과가 가장 우수한 군주는 Azospirillum sp.였다. 군주에 의한 식물생장 촉진 효과가 높은 재배방식 및 배지는 코코피트경 > 필라이트경 = 암면경 등의 순이었다.

• 농업과학연구
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• 제43권1호
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• pp.100-108
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• 2016

An auxin-producing bacteria (strain 5-1) was isolated from button mushroom compost in Boryeong-Si, Chungcheongnam-Do. The 5-1 strain was classified as a novel strain of Enterobacter aerogenes based on chemotaxonomic and phylogenetic analyses. The isolated E. aerogenes 5-1 was confirmed to produce indole-3-acetic acid (IAA), one of the auxin hormones, using TLC and HPLC analyses. When the concentration of IAA was assessed by performing HPLC quantitative analysis, a maximum concentration of IAA of $109.9mgL^{-1}$ was detected in the culture broth incubated in R2A medium containing 0.1% L-tryptophan for 24 h at $35^{\circ}C$. Acidification of the culture was deemed caused by an increase of IAA because a negative relationship between IAA production and pH was observed. Supplementation with a known precursor of IAA production, L-tryptophan, appeared to induce maximal production at 0.1% concentration, but it reduced production at concentrations above 0.2%. To investigate the growth-promoting effects to crops, the culture broth of E. aerogenes 5-1 was used to inoculate water cultures and seed pots of mung bean and lettuce. In consequence, adventitious root induction and root growth of mung bean and lettuce were two times higher than those of the control.

• 농업과학연구
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• 제37권3호
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• pp.377-382
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• 2010

An auxin-producing bacterium (AMT-54) was isolated from ginseng cultivating soil of Geumsan area. The isolate AMT-54 was confirmed to produce indole-3-acetic acid (IAA) which is one of auxin hormone by TLC analysis. When the concentration of IAA was assessed by performing HPLC quantitative analysis, the maximal 457ppm of IAA was detected from the culture filtrate after culturing in R2A broth containing 0.1% tryptophan for 24h at $35^{\circ}C$. The molecular weight of the main peak obtained by LC-mass analysis was correspondent well to 175, that of IAA. The strain AMT-54 was identified as a novel species belongs to Klebsiella mobilis by a chemotaxanomic and phylogenetic analysis. To investigate the growth promoting effect of crop, when the culture broth of K. mobilis AMT-54 was infected onto seed pot of mung bean, the adventitious root induction and root growth of mung bean were 3.3times higher than control.

• KSBB Journal
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• 제30권3호
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• pp.97-102
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• 2015

This study aimed to evaluate the potential plantgrowth promoting effects of potassium polyacrylate, a superabsorbent polymer, and Bacillus sp. SH1RP8, a family of plant-growth-promoting bacteria. Potassium polyacrylate was selected as the polymer for use due to its high molecular weight and its ability to retain and continuously supply moisture. Plant-growth-promoting rhizobacteria (PGPR) were isolated from the soil and applied to plants growing in dry environments, such as saline conditions. The moisture absorption and retention abilities of potassium polyacrylate were evaluated at a high temperature ($50^{\circ}C$) and in a dry condition, during which time the polymer showed a water retention potential of 19606.07% after 29 days. To overcome the reaming problem in the soil environment, natural polymers (such as cellulose) were mixed with the potassium acrylate. The shoot growths of Peucedanum japonicum Thunb and Arundo donax were significantly enhanced when treated with the mixture of the isolated rhizosphere bacterium SH1RP8 and potassium polyacrylate (63.5 and 124.3%, respectively).

• 한국토양비료학회지
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• 제49권4호
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• pp.355-367
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• 2016

Soil salinization refers to the buildup of salts in soil to a level toxic to plants. The major factors that contribute to soil salinity are the quality, the amount and the type of irrigation water used. The presented review discusses the different sources and causes of soil salinity. The effect of soil salinity on biological processes of plants is also discussed in detail. This is followed by a debate on the influence of salt on the nutrient uptake and growth of plants. Salinity decreases the soil osmotic potential and hinders water uptake by the plants. Soil salinity affects the plants K uptake, which plays a critical role in plant metabolism due to the high concentration of soluble sodium ($Na^+$) ions. Visual symptoms that appear in the plants as a result of salinity include stunted plant growth, marginal leaf necrosis and fruit distortions. Different strategies to ameliorate salt stress globally include breeding of salt tolerant cultivars, irrigation to leach excessive salt to improve soil physical and chemical properties. As part of an ecofriendly means to alleviate salt stress and an increasing considerable attention on this area, the review then focuses on the different plant growth promoting bacteria (PGPB) mediated mechanisms with a special emphasis on ACC deaminase producing bacteria. The various strategies adopted by PGPB to alleviate various stresses in plants include the production of different osmolytes, stress related phytohormones and production of molecules related to stress signaling such as bacterial 1-aminocyclopropane-1-carboxylate (ACC) derivatives. The use of PGPB with ACC deaminase producing trait could be effective in promoting plant growth in agricultural areas affected by different stresses including salt stress. Finally, the review ends with a discussion on the various PGPB activities and the potentiality of facultative halophilic/halotolerant PGPB in alleviating salt stress.

• The Plant Pathology Journal
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• 제21권1호
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• pp.7-12
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• 2005

Plant growth-promoting rhizobacteria (PGPR) are a wide range of root-colonizing bacteria with the capacity to enhance plant growth and control plant pathogens. Here we review recent progress that indicate some PGPR strains release a blend of volatile organic compounds (VOCs) that promote growth in Arabidopsis seedlings and induce resistance against Erwinia carotovora subsp. carotovora. In particular, the volatile components 2,3-butanediol and acetoin released exclusively from the PGPR strains triggered the greatest level of growth promotion and induced systemic resistance. Pharmacological applications of 2,3-butanediol promoted the plant growth and induced resistance, while bacterial mutants blocked in 2,3-butanediol and acetoin synthesis was devoid of growth-promotion and induced resistance capacities. The results suggested that the bacterial VOCs play a critical role in the plant growth promotion and induced resistance by PGPR. Using transgenic and mutant lines of Arabidopsis, we provide evidences that the signal pathway activated by volatiles from one PGPR strain is dependent on cyto-kinin activation for growth promotion and dependent on an ethylene-signaling pathway for induced pathogen resistance. This discovery provides new insight into the role of bacterial VOCs as initiators of both plant growth promotion and defense responses in plants.

• 한방안이비인후피부과학회지
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• 제15권2호
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• pp.53-79
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• 2002

To screen the effective materials for hair loss treatment, several natural extracts were tested using in vivo and in vitro test models. Firstly, all test materials were applicated onto the back skin of C57BL／6 mouse and then hair growth promoting effect was measured using hair growth index. As a result, Prunus mume, black bean, Brassica campestris subsp. black sesame and Rubi Fructus showed potent hair growth promoting effect, ranking as 1.5-2.0 of hair growth index. However, there were no plant extracts, which have remarkable potential of growth promotion of human hair dermal papilla cells cultured in vitro. In the experiments of 5${\alpha}$-reductase type Ⅱ inhibition assay, Prunus mume, Eriobotryae Folium showed effective potential to inhibit the activity of 5${\alpha}$-reductase type Ⅱ. To investigate the possible involvement of the effect of several plant extracts on the gene expression of growth factors in human hair dermal papilla cells, RT - PCR analyses were performed. However, there were no plant extracts, which have profound effect on the gene expression of several growth factors such as IGF-I, KGF, HGF and VEGF in the dermal papilla cells. Another tests for inhibition of microbial such as P. acne were also carried out to find whether these plant extracts have anti -microbial activities. Rubi Fructus showed anti -microbial effects on Propionibacterium acnes, which is believed as a pathogen of acne. Together, these results showed several plant extracts can be used for hair growth promotion.

• 한국균학회지
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• 제43권1호
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• pp.71-76
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• 2015

수생식물 샘플은 낙동강과 금호강이 만나는 달성습지에서 자라풀을 채집하였다. 자라풀의 뿌리에서 내생균류를 분리하고 형태가 다른 균주를 관찰하여 최종적으로 16개 균주를 선발하였다. 내생균류의 배양여과액은 식물생장촉진활성 검정을 위하여 난장이벼에 처리하여 스크리닝하였으며, HD1008 균주가 식물생장촉진활성이 가장 높은 것으로 확인되었다. HD1008 균주의 배양여과액을 HPLC와 GC/MS-SIM을 이용하여 분석하였고, HD1008 균주가 식물호르몬인 지베렐린 $GA_1$ (1.2 ng/100 mL)과 $GA_4$ (5 ng/100 mL) 를 생산하는 것을 정량분석을 통하여 확인하였다. 또한, HD1008균주의 beta-tubulin 유전자 염기서열을 이용하여 동정에 이용하였으며, 분자적인 방법과 형태적인 방법으로 관찰하였을 때, 지베렐린을 생산하는 새로운 P. trzebinskii로 동정되었다.

• Journal of Microbiology and Biotechnology
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• 제17권11호
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• pp.1805-1810
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• 2007

Purple nonsulfur bacteria were isolated from river sediments and their growth promoting capabilities on tomato were examined. Isolated strains KL9 and BL6 were identified as Rhodopseudomonas spp. by 16S rDNA sequence analysis. Rhodopseudomonas strain KL9 maximally produced 5.56 mM/min/mg protein and $67.2\;{\mu}M/min/mg$ protein of indole-3-acetic acid (IAA) and 5-aminolevulinic acid (ALA), respectively, which may be one of the mechanisms of plant growth enhancement. The germination percentage of tomato seed, total length, and dry mass of germinated tomato seedling increased by 30.2%, 71.1%, and 270.8%, respectively, compared with those of the uninoculated control 7 days after inoculation of strain KL9. The lengths of the root and shoot of germinated seedling treated with 3 mM tryptophan, a precursor of IAA, increased by 104.4% and 156.5%, respectively, 7 days after inoculation of strain KL9. Rhodopseudomonas KL9 increased 123.5% and 54% of the root and shoot lengths of germinated seedling, respectively, treated with 15 mM glycine and succinate, precursors of ALA. This plant growth promoting capability of purple nonsulfur bacteria may be a candidate for a biofertilizer in agriculture.