• 한국조경학회지
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• 제31권3호
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• pp.107-113
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• 2003

Ecological control can contribute to the sustainibility of vegetation management systems by reducing the input currently derived from non-renewable fossil energy sources. The use of turfgrass mixtures is an important tool in turf management. Turfgrass mixtures of two or more compatible and adapted species provide improved tolerance to pest and environmental stress, more so than monostands. The objectives of this study were to evaluated turf insects, pests and zoysia large patch control by turgrass mixtures. In April 2001 and 2002, plots were inoculated with 50g of Rhizoctonia solani AG2-2LP inoculum. Inoculum were treated within a 29cm diamater circle at Zoysia japonica, Zoysia japonica, Poa pratenis, or Festuca arundinacea mixtures. After four weeks, disease severity in each plot was determined. plot area visual ratings were assessed visually on a linera 0 to 100%. In August 2001 and October 2002, turf insects and pests in each plot were investigated in 10cm deep soil cores with 8cm diameters using hole cut. Zoysia large patch affected zoysiagrass monostands more severly than zoysiagrass and cool-season turfgrasses mixtures. It was suggested that the barrier effect of cool-season turfgrass suppressed zoysia large patch in the mixture of zoysiagrass and cool-season turfgrasses. Also, warm-season and cool-season turfgrasses mixtures suppressed insect populations more efficiently than warm-season turfgrass monostands.

• Plant Biotechnology Reports
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• 제2권1호
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• pp.13-20
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• 2008

Potato (Solanum tuberosum L.), one of the most important food crops, is susceptible to a number of devastating fungal pathogens in addition to bacterial and other pathogens. Producing disease-resistant cultivars has been an effective and useful strategy to combat the attack of pathogens. Potato was transformed with Agrobacterium tumefaciens strain EHA101 harboring chitinase, (ChiC) isolated from Streptomyces griseus strain HUT 6037 and bialaphos resistance (bar) genes in a binary plasmid vector, pEKH1. Polymerase chain reaction (PCR) analysis revealed that the ChiC and bar genes are integrated into the genome of transgenic plants. Different insertion sites of the transgenes (one to six sites for ChiC and three to seven for bar) were indicated by Southern blot analysis of genomic DNA from the transgenic plants. Expression of the ChiC gene at the messenger RNA (mRNA) level was confirmed by Northern blot analysis and that of the bar gene by herbicide resistance assay. The results obviously confirmed that the ChiC and bar genes are successfully integrated and expressed into the genome, resulting in the production of bialaphos-resistant transgenic plants. Disease-resistance assay of the in vitro and greenhouse-grown transgenic plants demonstrated enhanced resistance against the fungal pathogen Alternaria solani (causal agent of early blight).

• 한국유기농업학회지
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• 제24권3호
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• pp.465-484
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• 2016

본 연구는 자생식물인 순비기나무, 번행초, 사철쑥 등을 이용하여 친환경 농자재로 개발하기 위한 기초자료를 제공하고자 수용성 추출액 농도에 따른 Stemphylium vesicarium, Penicillium italicum, Sclerotinia sclerotiorum, Pythium ultimum, Botrytis cinerea, Rhizoctonia solani, Colletotrichum gloeosporioides 7종의 작물 병원균에 대해 생장을 조사하였다. 공여체식물별에 따른 수용성 추출액 농도가 증가됨에 따라 작물 병원균 균사의 생장이 감소하는 경항을 보이나 공여체식물과 병원균의 종류에 따라 억제의 정도차이를 보였다. Stemphylium vesicarium 경우 번행초와 사철쑥에서 농도 증가에 따라 각각 r = -0.857 (p<0.01), r = -0.868 (p<0.01)로 역의 상관을 보였고 Penicillium italicum은 순비기나무 r = -0.833 (p<0.01), Sclerotinia sclerotiorum은 순비기나무 r = -0.862 (p<0.01)와 사철쑥 r = -0.902 (p<0.01), Botrytis cinerea은 번행초 r = -0.896 (p<0.01)에서 역의 상관을 보였으며 Rhizoctonia solani과 Colletotrichum gloeosporioides은 모든 공여체식물에서 역의 상관을 보였다. 100% 처리구에서 균사의 생장억제 활성은 번행초인 경우 Pythium ultimum, Botrytis cinerea, Colletotrichum gloeosporioides에 대해 각각 94%, 50%, 80%의 억제율을 보였다. 사철쑥인 경우 Stemphylium vesicarium, Pythium ultimum에 대해 각각 43%, 90%의 억제율을 보였다. 황근은 Penicillium italicum, Sclerotinia sclerotiorum에서 각각 50%, 26%가 억제되었으며 무화과는 Rhizoctonia solani에 대해 74%가 균사 생장이 억제되었다. 항균활성을 보이는 수용체식물의 총 페놀 및 플라보노이드 함량은 사철쑥 16.15 mg/g, 무화과 7.81 mg/g, 순비기나무 6.18 mg/g, 황근 5.25 mg/g, 번행초 4.41 mg/g 순으로 조사되었고 플라보노이드는 사철쑥 27.57 mg/g, 순비기나무 12.49 mg/g, 무화과 11.45 mg/g, 황근 5.77 mg/g, 번행초 5.08 mg/g 순으로 분석되었다.

• 한국미생물·생명공학회지
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• 제25권1호
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• pp.30-36
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• 1997

To genetically breed powerful multifunctional antagonistic bacteria, the urease gene of alkalophilic Bacillus pasteurii was transferred into Bacillus subtilis YB-70 which had been selected as a powerful biocontrol agent against root-rotting fungus Fusarium solani. Urease gene was inserted into the HindIII site of pGB215-110 and designated pGU266. The plasmid pGU266 containing urease gene was introduced into the B. subtilis YB-70 by alkali cation transformation system and the urease gene was very stably expressed in the transformant of B. subtilis YB-70(pGU266). The optimal conditions for the transfomation were also evaluated. From the in vitro antibiosis tests against F. solani, the antifungal activity of B. subtilis YB-70 containing urease gene was much efficient than that of the non-transformed strain. Genetic improvement of B. subtilis YB-70 by transfer of urease gene for the efficient control seemed to be responsible for enhanced plant growth and biocontrol efficacy by combining its astibiotic action and ammonia producing ability.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.88.1-88
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• 2003

Antogonistic bacteria against Rhizoctonia solani and Pythium spp., causing serious damage to golf course grasses, were isolated from the top soil of several golf courses in Korea. The isolate of Limk0102 was selected as the biological agent by characterization of antifungal activity, large scale preparation, fungicides tolerance and ecological fitness to the targe environment. The isolate was identified as Bacillus subtilis by biochemical and physiological characterization, and 165 rDNA sequence analysis. The bacterial agent was formulated as a granule type by seeding it on fine sand. The formulated agent showed high recovery rate (more than 10$\^$8/ cells/g sand) even after 6 month-storage at room temperature with similar antifungal activity with that of original cells. In vitro, the biological agent successfully exhibited antagonistic performance on bentgrass inoculated with R. solani or Pythium spp. isolated from the diseased grasses on golf courses. Field evaluation on disease control activity and ecological fitness of the agent is now under going on several golf courses.

• Applied Biological Chemistry
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• 제32권4호
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• pp.401-407
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• 1989

생리활성을 갖는 신규물질 탐색의 일환으로 1,3 치환 -5-chloropyrazole-4-carbonyl chloride를 합성한 뒤 8종의 aldoxime 또는 ketoxime과 친핵 반응시켜 15종의 pyrazole-oxime ester를 얻었으며, 이들의 구조를 $^1H,\;^{13}C-NMR$ 및 IR 등으로 확인하였다. 이 유도체들의 R. solani, P. oryzae, B. cinerea, P. graminearum, P. capsici 및 G. cingulata에 대한 균사생육억제효과를 검정한 결과, oxime 부위$(R^3)$가 친전자성기로 치환된 방향족인 경우가(III, XIII, XIV) 포화알킬기인 경우보다 우수한 효과를 보여주었다.

• Journal of Microbiology and Biotechnology
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• 제5권2호
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• pp.80-86
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• 1995

The bacterial strain WC-17 able to produce chitinase was isolated from soil using an enrichment technique. The isolated strain was identified as Acinetobacter sp. judging by their morphological and physiological characterisitics. The optimal culture conditions for the production of chitinase of Acinetobacter sp. WC -17 are 1.5% colloidal chitin and 1 % tryptone at $30^{\circ}C$ with pH 6.5. Since the enzyme was rapidly produced in a culture supplied with chitin, glucose, or N-acetylglucosamine but not with other polymers and monosaccharide, the enzyme was considered to be an inducible enzyme. Notably N- acetylglucosamine and glucose were found to be effective inducers at low concentrations but repressors at excessive concentrations. The cultural supernatant of Acinetobacter sp. WC-17 inhibited the growth of phytopathogenic fungi such as P.oryzae, R.solani, and F.solani. Among the phytopathogenic fungi tested, P.oryzae was the most sensitive. The conventional agar plate (PDA containing 1 % colloidal chitin) method also produced the same result.

• Applied Biological Chemistry
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• 제39권1호
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• pp.20-24
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• 1996

근권토양에서 분리한 형광성 P. fluorescens ps88은 철이 결핍된 환경에서 2차대사산물인 siderophore라는 형광성물질을 분비하며, KMB배지에서 Pythium ultimum, Pyricularia oryzae, Rhizoctonia solani 및 Xanthomonas oryzae의 생육을 억제시켰다. 오이의 씨앗을 P. fluorescens ps88로 접종한 후 Fusarium의 발병율을 조사하였을 때 ps88 접종구에서는 이병율이 대조구에 비하여 50%가 감소하였다. Vermiculate에서 균을 접종한 후 오이의 생육촉진효과를 조사한 결과 대조구보다 현저한 생육증가가 관찰되었으며, MS배지에서 고추의 뿌리에 siderophore를 처리하였을 때 대조구에 비하여 미세한 뿌리의 발달이 관찰되었다.

• KSBB Journal
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• 제30권3호
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• pp.132-139
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• 2015

In order to use the symbiotic bacteria from ethomophatogenic nematodes as a biological control agent for agriculture, the cultural condition for maintaining phase I and antifungal activity was investigated. Symbiotic bacteria (SB) 1 stain from nematodes were selected from the three strains isolated from entomopathogenic nematodes. The growth of the SB 1 strain in NB, TSB, TY and YS medium was higher than that of the SB 2 and SB 3 strain. The packed cell volume of the SB 1 strain was reduced in NB medium which showed radical pH change. Phase I of the SB 1 strain was maintained in TSB medium after being stored for 2 weeks at $4^{\circ}C$. Culture broth with the SB 1 strain in TSB medium for 6 days and 7 days showed antifungal activities against Rhizoctonia solani KACC 40142, Botrytis cinerea Pers. KACC 40854, and Botrytis cinerea Pers. KACC 41008. Culture broth with the SB 1 strain in TSB medium containing 100 mM L-proline for 5 days showed antifungal activities against Rhizoctonia solani KACC 40142, and Botrytis cinerea Pers. KACC 40854.

• The Plant Pathology Journal
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• 제34권3호
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• pp.218-235
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• 2018

Plant growth promoting rhizobacteria and endophytic bacteria were isolated from different varieties of turmeric (Curcuma longa L.) from South India. Totally 50 strains representing, 30 PGPR and 20 endophytic bacteria were identified based on biochemical assays and 16S rDNA sequence analysis. The isolates were screened for antagonistic activity against Pythium aphanidermatum (Edson) Fitzp., and Rhizoctonia solani Kuhn., causing rhizome rot and leaf blight diseases in turmeric, by dual culture and liquid culture assays. Results revealed that only five isolates of PGPR and four endophytic bacteria showed more than 70% suppression of test pathogens in both assays. The SEM studies of interaction zone showed significant ultrastructural changes of the hyphae like shriveling, breakage and desication of the pathogens by PGPR B. cereus (RBacDOB-S24) and endophyte P. aeruginosa (BacDOB-E19). Selected isolates showed multiple Plant growth promoting traits. The rhizome bacterization followed by soil application of B. cereus (RBacDOB-S24) showed lowest Percent Disease Incidence (PDI) of rhizome rot and leaf blight, 16.4% and 15.5% respectively. Similarly, P. aeruginosa (BacDOB-E19) recorded PDI of rhizome rot (17.5%) and leaf blight (17.7%). The treatment of these promising isolates exhibited significant increase in plant height and fresh rhizome yield/plant in comparison with untreated control under greenhouse condition. Thereby, these isolates can be exploited as a potential biocontrol agent for suppressing rhizome rot and leaf blight diseases in turmeric.