• 한국유기농업학회지
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• 제6권1호
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• pp.133-149
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• 1997

Recently, the importance of management and cultivation of grasses has been increased in Korea. Among these cultural practices, the appropriate control of diseases is considered more important than other cultivation techniques such as fertilization and irrigation. The damages of brown patch and large patch caused by Rhizoctonia spp. and Pythium blight caused by Pythium spp. are serious in the major cultivation area of turfgrass in Korea. Since these diseases are difficult to control by agrochemicals, the damages are very serious if these are occured. The periodic spray of agrochemicals, to protect and control these diseases could make some problems of toxicity and environmental pollution as well as rising of non-target diseases. Therefore, the biological methods to control diseases have been required to decrease problems resulted from overuse of agrochemicals, to conserve natural ecosystem, and to control effectively diseases of grasses in the long period. The number of studies about biological control using antagonistic microorganisms have been increased for last half century. However, the application of biological control method has been very limited. In this study, thirteen isolates of R. cerealis, 8 isolates of R. solani and 3 isolates of Phthyn spp. have been isolated from diseased turfgrass in golf course and grass-culture area that have patch and wilting symptoms of zoysia grass and creeping bentgrass. Isolation frequency of R. cerealis and R. solani was high in especially zoysiagrass, while Pythym spp. was isolated from bent grass at low frequency but showed high pathogenicity. Totally, 205 isolates of soil microorganisms were isolated in this study as primary antagonistic microorganism by Herr's triple agar layer plate and dual culture method using rhizosphere of grasses, soil of crop field as the source of antagonistic microorganisms. Among the 205 isolates, 23 isolates were actinomycetes and 182 isolates were bacteria. All of the actinomycetes were isolated by Herr's method. Antagonistic effect of primary isolated microorganisms was tested for in vitro mycelial growth inhibition against pathogenic fungi isolated from grasses and for inhibition of disease occurrence in 24 well tissue culture plate and pot experiment. Then, four isolated of bacteria which are BG23, BG74, BG136 and BG171 were selected as antagonistic microorganisms against soil-born pathogenic fungi of bentgrass.

• 한국환경농학회지
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• 제31권1호
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• pp.68-74
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• 2012

BACKGROUND: Some microorganisms extant in nature have ability to suppress various plant pathogens, and also can promote plant growth. Thus microorganisms are such great source of antimicrobial agents to develop antagonistic microorganism production and eco-friendly crop management. We isolated the microorganisms in various eco-friendly formulations. The suppressive abilities against plant pathogens have been characterized in vitro level. METHODS AND RESULTS: The indigenous microorganisms have been isolated from Cooked rice, Black sugar, Rice Bran, and Red clay using dilution plating method. Population of bacteria and fungi were above 107 in the all formulations. We isolated and pure cultured the microorganisms based on morphological characteristics. Three major plant pathogens (Fusarium oxysporum, Rhizoctonia solani, Phytophthora capsici) have been used to select antagonistic microorganisms. Total 20 bacteria and 9 fungi showed the pathogen growth suppression ability in vitro condition. The selected microorganisms were identified by ITS sequence similarity. CONCLUSION: All tested eco-friendly formulations contained high-density of the microorganisms. Among the isolated microorganisms, Bacillus spp. and Streptomyces spp. showed the most effective antifungal activity against the plant pathogens such as F. oxysporum, R. solani, and P. capsici. Among the selected fungi Trichoderma sp. demonstrated antifungal activity. Our results suggest that the currently adapted eco-friendly formulations might useful for sustain agricultural system.

• 한국산업융합학회 논문집
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• 제2권1호
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• pp.85-90
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• 1999

The possibility of employment of ceramics, known to be emitting far infrared waves, to keep the growth and the viability of the antagonistic microorganisms was examined. Among four kinds of commercial ceramics, the ceramic powders composed of soft ferrite as a main component has exhibited to grow Pseudomonas cepacia and Saccharomyces cerevisiae better. The ceramic powder in the growth medium has increased the number of cells of P. cepada about ten times and that of S. cerevisiae two to five times more than that in the control at $27^{\circ}C$. The viability of the microorganism at low temperature which was measured from the regrowth behavior at $27^{\circ}C$ after five days store at $4^{\circ}C$ has shown that the lag time of the two microorganisms reduced about three hours without any defect in the rate of logarithmic growth. These results demonstrated that the ceramic powders was available to the growth and viability at low temperature of antagonistic microorganisms.

• 한국유기농업학회지
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• 제5권1호
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• pp.137-147
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• 1996

For the purpose of acquiring microbial agents that can be utilized to biologically control the major airborne diseases to apple trees, such as canker(Botryosphaeria dothidea), bitter rot(Glomerella cingulata), alternaria leaf spot(Alternaria mali), root rot(rosellinia necatrix), canker(Valsa ceratosperma) and gray mold rot(Botrytis cinerea), the effective microorgaisms were isolated, tested for antagonistic activity to the pathogens causing major diseases to apple trees and identifed. Screening of more than 5,000 species of microorganisms collected in nature for them antagonistic action to the pathogens causing 5 major diseases to apple trees resulted in selection of effective species. Out of the 11 species, one species designated as CAP134 demonstrated outstanding activity. The bacterial strain, CAP134 exerted antagonistic efficiency of 57% on an isolated strain and 40% on a donated strain of Botryosphaeria dothidea., 52% on an isolated strain and 46% on a purchased strain of Alternaria mali, 60% on Valsa ceratosperma 25% on Glomerella cingulata, and 64% Rosellinia necatrix. The CAP134 was identified as a bacterial strain to Bacillus subtilis ATCC 6633 based on morephology, culture conditions, and physio-biochemical characteristics.

• 한국유기농업학회지
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• 제6권1호
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• pp.35-43
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• 1997

For the purpose of acquiring microbial agents that can be utilized to billogically control the major airborne disease to apple trees, such as canker(Valsa ceratosperma), the effective microorgaisms were isolated, tested for antagonistic activity to the pathogen causing major disease to apple trees and identifed. Screening of more than 3, 000 species of microorganisms collected in nature for them antagonistic action to the pathogen, Valsa ceratosperma causing disease to apple tree resulted in selection of effective species. Out of the 11 species, one species designated as CAP141 demonstrated outstanding activity. The bacterial strain, CAP141 exerted antagonistic efficiency of 65% on Valsa ceratosperma. The CAP141 was identified as a bacterial strain to Bacillus subtilis based on morphology, culture conditions, and physio-biochemical characteristics.

• 한국약용작물학회지
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• 제20권5호
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• pp.339-344
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• 2012

This study was carried out to research microorganisms having the antifungal activity against ginseng Alternaria blight pathogen Alternaria panax and ginseng anthracnose pathogen Colletotrichum gloeosporioides. Eleven Bacillus strains. were isolated from Korean traditional soybean paste and Kimchi. Among the 11 isolates, DJ5, KC1, KC2 and KC4 showing antagonistic activity on the mycelial growth of A. panax and C. gloeosporioides in pairing culture were finally selected as the antagonistic microorganisms. Based on 16s rRNA sequence and phylogenetic tree analysis, they were identified as Bacillus spp.. The selected microorganisms were investigated antagonistic activity by measured leaf-segment colonization in pot test. When Bacillus sp. were injected after A. panax treatment, KC1, KC2 and KC4 showed similar effect to chemical pesticides treated control. To measure preventive effect of Bacillus sp, antagonistic microorganisms were injected and C. gloeosporioides was treated in pot. When measuring the effectiveness for the prevention of Anthracnose, All Bacillus spp. showed approximately 83~90 % degree of superior preventive effect. In general, The four Bacillus spp. isolated from Korean traditional fermented foods showed therapeutic effect of Alternaria blight and preventive effect of Anthracnose.

• 아시안잔디학회지
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• 제13권4호
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• pp.201-212
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• 1999

In use of pesticides in golf courses has been increased steadily. Environmental concern as well as decrease in efficiency led the turfgrass management into an alternate approach of using beneficial microorganism to deal with turfgrass pests. This study was focused on the use of such microorganisms for improving cultural environment and minimizing the use of pesticides. Microorganisms antagonistic to turfgrass diseases were applied to zoysiagrass fairways and creeping bentgrass greens in Yusung country club. Tharch accumulation, disease occurrence, and other cultural environments were compared among the combinations of microorganisms and suppliemental N applications. The application of microorganisms antagonistic to turfgrass diseases improved turf resiliency. Thatch thickness was 3.03cm in the control plot but it was 2.11cm in plots treated by microorganisms, indicating significant effects of microorganism application on reduction of thatch accumulation. Number of microorganism that can decompose of cellulose was higher at the plots treated with useful microbial products and it was considered that existence of higher population of microorganisms resulted in reduction of thatch accumulation. In the evaluation of relationship between thatch accumulation and disease occurrence, greater thatch accumulation was observed at the golf courses which have been frequently infested by large patch. However, the rate of thatch accumulation varied among surveyed golf courses regardless of the year of turf establishment. Therefore, management practice which can be effective for reduction of thatch could result in large patch suppression. The application of microorganisms on the established turfgrasses reduced the occurrence rate of pythium blight and yellow path diseases, whereas occurrence of brown patch and dollar spot increased.

• 아시안잔디학회지
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• 제8권1호
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• pp.47-52
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• 1994

Attempts were made to investigate the antagonistic activity of soil borne microorganisms Pseudomonas spp. and Trichoderma spp. against to the pathogens of turf diseases Rhizoctionia solani spp. and Pythiom spp. in vitro by a dual culture bioassay. Inhibition zone between the edge of the my-celium and the margin of each antagonistic bacteria, Pocudontonas, on potato dextrose agar was measured 3 days after incubation at 28˚C. Psudomonas spp. showed relatively high inhibition of mycelium growth of R. solani AG-i and Pythium spp. which cause brown patch and pythium blight, respectively. Antagonistic fungi Trichodenma spp. also showed effective inhibition against mycelium growth of both pathogens, more proper methods of measuring the inhibition effects were required because of fast growth of Trichodenna hypae. Brown patch and pythium blight both, re-quire most higher rate of fungicide use to control in golf curses in Korea. Application of antagon-istic microorganisms are useful as biological resources an approach to sole environmental contamination.

• 한국산학기술학회논문지
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• 제20권12호
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• pp.110-116
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• 2019

Probiotics와 다양한 병원성 미생물간의 혼합배양에서의 길항적 억제효과를 조사하기 위해 2016년 1월부터 12월까지 국내 김치로부터 다양한 probiotics 균주를 분리하여 16S rRNA sequencing을 통한 계통학적 분석을 통해 140주의 프로바이오틱스를 동정하였다. 이중 항균력이 우수한 probiotics 4종(Enterococcus faecalis, Lactobacillus plantarum, Lactobacillus rhamnosus, and Lactobacillus reuteri )과 병원성 미생물 6종 (Candida albicans, Salmonella Enteritidis, E. coli O157:H7, Shigella flexneri, Staphylococcus aureus, and Pseudomonas aeruginosa)간의 혼합배양에서의 길항적 억제시험에서 probiotics 균주들은 대부분 배양 후에 균수가 정상적으로 크게 증가했지만 C. albicans를 포함하여 대부분의 병원성미생물들은 S. Enteritidis 를 제외하고 거의 완전하게 성장이 억제되었다. 이러한 in vitro 에서의 길항적 억제효과는 생성된 젖산과 유기산등의 낮은 pH에 의한 효과인 것으로 생각된다. 이상의 결과로 한국 김치에서 분리된 probiotics 균주 4종은 여성질염, 대장 및 피부관리 관련 치료제로써의 개발 가능성이 매우 큰 것으로 생각되며 향후 이러한 치료제는 probiotics 관련 국민건강 및 보건향상에 크게 기여할 것으로 생각된다.

• Journal of Microbiology and Biotechnology
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• 제5권6호
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• pp.346-352
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• 1995

For isolation of antibiotic-producing bacteria antagonistic to Fusarium oxysporum, a total of 327 microorganisms were screened from sesame-growing soils collected at various locations in Korea by the modified Herr's triple-agar-Iayer technique. Among the 36 bacterial isolates further screened by the dual culture test on tryptic soy agar, 10 were tested to show their antagonistic activity against 14 plant pathogenic fungi. Bacterial culture filtrates were shown either to inhibit some phytopathogenic fungal growth or to suppress F. oxysporum infection of sesame plants maintained in the green house. An isolate, B23, with the most prominent antagonistic activity was identified as Bacillus subtilis.