• The Plant Pathology Journal
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• 제22권2호
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• pp.119-124
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• 2006

Kudzu vine(Pueraria montana var. lobata) is an invasive climbing woody vine that envelops trees and shrubs, pressing physically and shutting out sunlight, which needs to be controlled. Kudzu vine pathogens were surveyed as a way to seek its biocontrol agents in 2002. Occurrence of a bacterial halo blight disease of kudzu vine was observed at several localities in Korea including Euiwang and Suwon in Gyeonggi Province, Daejon, and Gochang and Buan in Jeonbuk Province. Symptoms of brown to black spots with a surrounding yellowish halo appeared from June and lasted till the rainy season without much expansion, but accompanying often leaf blight and defoliation. Isolated bacteria were identified as Pseudomonas syringae pv. phaseolicola based on physiological and cultural characteristics, Biolog, fatty acid and 16S rDNA sequencing analyses. In artificial inoculation test, these bacteria produced the same halo spot symptoms on kudzu vine and bean plants. They also induced hypersensitive responses (HR) on tobacco, tomato, and chili pepper leaves. This is the first report of a bacterial disease of kudzu vine in Korea, and the bacterial pathogen can be used as a biocontrol agent against the pest plant.

• The Plant Pathology Journal
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• 제23권3호
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• pp.193-202
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• 2007

Typical susceptible symptoms of the bacterial pustule disease caused by Xanthomonas axonopodis pv. glycines are pustule and chlorotic haloes that usually occur in leaves of Glycine max plants. The soybean genotype 'PI96188' showed an atypical response to all tested races X. axonopodis pv. glycines, accompanied with necrosis without chlorotic haloes on the underside of the necrotic symptoms. X. axonopodis pv. glycines 8ra grew to levels from 10 to 100 fold lower on PI96188 than on susceptible cultivar Jinjoo1, but 10-fold higher than on the resistant cultivar CNS. The chlorophyll content in PI96188 leaves remained unchanged until 12 days after bacterial infection. Ultrastructural observation showed that the infected leaf cells of PI96188 had intact normal chloroplasts compared to those of the susceptible cultivar Jinjoo1. Chloroplast degradation or the absence of chloroplasts in cells of the infected tissues was observed in Jinjoo1. Senescence-related ACS7 gene was significantly induced in PI96188 compared to those in Jinjoo1 at 2 days after inoculation. While photosynthesis-related rbcS gene showed the dramatic change in Jinjoo1, this gene was constitutively expressed in PI96188. However, expression of the defense-related genes, such as peroxidase and isoflavone synthase in the infected PI96188 leaves was similar to that in Jinjoo1. Together, these results suggest that the novel necrotic symptom in PI96188 is a kind of resistant response different from a typical hypersensitive response in the resistant genotypes.

• Mycobiology
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• 제29권4호
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• pp.218-223
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• 2001

A rapid radicle assay for prescreening antagonistic bacteria to Phytophthora capsic4 causal agent of Phytophthora blight of pepper was developed. Sixty-four bacterial strains with in vitro antifungal activity selected out of 1,400 strains isolated from soils of Ansung, Chunan, Koyang, and Paju, Korea in 1998 were used for development of the bioassay. Uniformly germinated pepper seeds dipped in bacterial cells for 3 hours were placed near the edges of growing mycelia of P. capsici on water agar containing 0.02% glucose. Five-week-old pepper plants(cv. Nockwang) were inoculated to compare with results of the radicle assay developed in this study. For plant inoculation, pepper seeds were sown in potting mixtures incorporated with the bacterial strains, then transplanted into steam-sterilized soils 3 weeks later. Plants were hole-inoculated with zoospores of P. capsici 2 weeks after transplanting. Disease incidence and severity were determined in radicle and plant assessments, respectively. In radicle assay, six strains, GK-B15, GK-B25, OA-B26, OA-B36, PK-B09, and VK-B14 consistently showed the significant(P=0.05) disease reduction against radicle infection by the fungus, four of which also did in plant assessments. Strains OA-B36 and GK-B15 consistently reduced the fungal infection in both the radicle assay and the plant assessment. Therefore, prescreening strains using the radicle assay developed in this study followed by plant assay could reduce time and labor, and improved the possibility of selecting antagonistic bacteria for control of Phytophthora blight of peppers.

• 식물병연구
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• 제7권3호
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• pp.150-154
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• 2001

세균성벼알마름병의 발생 예측 모델을 만들기 위하여 출수기의 기상 환경과 병 발생과의 관계를 자료분석(1992~2000)과 온실 및 포장시험을 통해 조사하였다. 세균성벼알마름병의 발생이 많은 해는 '94, '95, '98, 2000년이었고, 중만생종 출수기인 8월 상.중순에 고온이 지속되면서 연속강우가 많았다. 반면 병 발생이 적었던 '93년은 강우량과 강우일수는 많았으나 저온이었고, '97년에는 온도는 높았으나 강우가 적은 경향이었다. 출수기에 접종 후 습실처리 하였을 때(24시간 이상) $10^2$cfu/ml에서부터 발병하기 시작하여 접종농도가 높을수록 발병도가 높아져 $10^{8}$ cfu/ml에서는 86.1%의 발병도를 보였다. 습실처리를 하지 않은 경우에는 $10^{8}$ cfu/ml에서만 12.5% 발병하였다. 또한 발병도가 증가함에 따라 천립중과 등숙률이 현저히 감소하였다.

• The Plant Pathology Journal
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• 제29권1호
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• pp.42-51
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• 2013

One of the most important limiting factors for the production of the grafted cactus in Korea is the qualitative and quantitative yield loss derived from stem rots especially caused by Bipolaris cactivora. This study is aimed to develop microbial control agents useful for the control of the bipolaris stem rot. Two bacteria (GA1-23 and GA4-4) selected out of 943 microbial isolates because of their strong antibiotic activity against B. cactivora were identified as Bacillus subtilis and B. amyloliquefaciens, respectively, by the cultural characteristics, Biolog program and 16S rRNA sequencing analyses. Both bacterial isolates significantly inhibited the conidial germination and mycelial growth of the pathogen with no significant difference between the two, of which the inhibitory efficacies varied depending on the cultural conditions such as temperature, nutritional compositions and concentrations. Light and electron microscopy of the pathogen treated with the bacterial isolates showed the inhibition of spore germination with initial malformation of germ tubes and later formation of circle-like vesicles with no hyphal growth and hyphal disruption sometimes accompanied by hyphal swellings and shrinkages adjacent to the bacteria, suggesting their antibiotic mode of antagonistic activity. Control efficacy of B. subtilis GA1-23 and B. amyloliquefaciens GA4-4 on the cactus stem rot were not as high as but comparable to that of fungicide difenoconazole when they were treated simultaneously at the time of pathogen inoculation. All of these results suggest the two bacterial isolates have a good potential to be developed as biocontrol agents for the bipolaris stem rot of the grafted cactus.

• Mycobiology
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• 제30권1호
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• pp.31-36
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• 2002

Soil bacteria were screened for the ability to control cucumber anthracnose caused by Colletotrichum orbiculare through induced systemic resistance(ISR). Sixty-four bacterial strains having in vitro antifungal activity were used for selecting ISR-inducing strains in cucumber. Cucumber seeds(cv. Baeknokdadagi) were sown in potting mixtures incorporated with the soil bacteria, at a rate of ca. $10^8$ cells per gram of the mixture. Two week-old plants were then transplanted into the steam-sterilized soil. Three leaf-stage plants were inoculated with a conidial suspension($5{\times}10^5$ conidia/ml) of C. orbiculare. Diseased leaf area(%) and number of lesions per $cm^2$ leaf were evaluated on third leaves of the plants, $5{\sim}6$ days after inoculation. Among 64 strains tested, nine strains, GC-B19, GC-B35, GK-B18, MM-B22, PK-B14, RC-B41, RC-B64, RC-B65, and RC-B77 significantly(P=0.05) reduced anthracnose disease compared to the untreated control. In contrast, some bacterial strains promoted susceptibility of cucumber to the disease. From the repeated experiments using the nine bacterial strains, GC-B19, MM-B22, PK-B14, and RC-B65 significantly(P=0.05) reduced both diseased leaf area(%) and number of lesions per $cm^2$ leaf in at lease one experiment. These strains with control efficacy of $37{\sim}80%$ were determined to be effective ISR-inducing strains.

• 생명과학회지
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• 제21권1호
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• pp.134-140
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• 2011

대전일원의 유류오염 지역의 토양으로부터 원유를 단일 탄소원으로 이용하는 총 145균주를 순수분리 하였고, 이중 생물 계면활성제 생성능이 가장 우수한 한 균주를 최종 선별하여 형태 및 생리 생화학적 특성을 조사하고 16S rRNA 염기서열을 분석을 통하여 동정한 결과 Pseudomonas sp.로 확인되어 Pseudomonas sp. Z1이라 명명하였다. 최종 선별된 Pseudomonas sp. Z1은 클로람페니콜과 암피실린 등의 항생제와 리튬, 망간, 바륨 등의 중금속에 대해 강한 내성을 갖고 있었고, 최적 온도와 pH는 각각 $30^{\circ}C$와 pH 6.0-7.0으로 확인되었다. Pseudomonas sp. Z1이 생성하는 생물 계면활성제는 배양 10시간 이후부터 배양액의 표면장력이 급격히 감소해, 배양 21시간 후에 최대 28 dyne/cm까지 감소되었고, 2% 이상의 NaCl을 첨가한 경우 배양액의 생물계면활성제의 활성이 감소하였다.

• 생물환경조절학회지
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• 제13권1호
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• pp.33-38
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• 2004

본 시험은 고랭지에서 착색단고추의 접목재배로 토경재배시 지하부 환경개선을 통해 토양전염성 병을 예방하고, 수량성을 향상시키고자 저항성 대목들을 수집하여 접목재배하여 생육, 수량 및 병저항성을 비교하였다. 접수는 적색계인 스피리트품종을 사용하였다. 역병균을 접종한 결과 자근묘인 Spirit는 접종 후 5일 만에 100% 고사하였고, 저항성이 높은 대목으로는 탄탄대목, Skurt-S, AC 2258, PST 8301 등 4품종이었다. 또한 청고병에 저항성이 높은 대목으로는 역강, 탄탄대목, TE 412, 갤럭시, MC 4, PST VK, PST NV 등 7품종이었다. 접목구는 지근묘에 비해 근중이 무거워 지하부의 환경개선효과가 뚜렷하였다. 접목과 비접목에 따른 과실의 외적 ${\cdot}$ 내적인 품질은 큰 차이가 없었다. 수량성이 높은 대목은 PST 8301, MC 4, 왕건 등이었다.

• The Korean Journal of Pain
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• 제36권1호
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• pp.11-50
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• 2023

As the field of interventional pain management (IPM) grows, the risk of surgical site infections (SSIs) is increasing. SSI is defined as an infection of the incision or organ/space that occurs within one month after operation or three months after implantation. It is also common to find patients with suspected infection in an outpatient clinic. The most frequent IPM procedures are performed in the spine. Even though primary pyogenic spondylodiscitis via hematogenous spread is the most common type among spinal infections, secondary spinal infections from direct inoculation should be monitored after IPM procedures. Various preventive guidelines for SSI have been published. Cefazolin, followed by vancomycin, is the most commonly used surgical antibiotic prophylaxis in IPM. Diagnosis of SSI is confirmed by purulent discharge, isolation of causative organisms, pain/tenderness, swelling, redness, or heat, or diagnosis by a surgeon or attending physician. Inflammatory markers include traditional (C-reactive protein, erythrocyte sedimentation rate, and white blood cell count) and novel (procalcitonin, serum amyloid A, and presepsin) markers. Empirical antibiotic therapy is defined as the initial administration of antibiotics within at least 24 hours prior to the results of blood culture and antibiotic susceptibility testing. Definitive antibiotic therapy is initiated based on the above culture and testing. Combination antibiotic therapy for multidrug-resistant Gram-negative bacteria infections appears to be superior to monotherapy in mortality with the risk of increasing antibiotic resistance rates. The never-ending war between bacterial resistance and new antibiotics is continuing. This article reviews prevention, diagnosis, and treatment of infection in pain medicine.

• The Plant Pathology Journal
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• 제39권4호
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• pp.409-416
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• 2023

Bacterial leaf blight of carrots caused by Xanthomonas hortorum pv. carotae (Xhc) is an important worldwide seed-borne disease. In 2012 and 2013, symptoms similar to bacterial leaf blight were found in carrot farms in Jeju Island, Korea. The phenotypic characteristics of the Korean isolation strains were similar to the type strain of Xhc. Pathogenicity showed symptoms on the 14th day after inoculation on carrot plants. Identification by genetic method was multi-position sequencing of the isolated strain JJ2001 was performed using four genes (danK, gyrB, fyuA, and rpoD). The isolated strain was confirmed to be most similar to Xhc M081. Furthermore, in order to analyze the genetic characteristics of the isolated strain, whole genome analysis was performed through the next-generation sequencing method. The draft genome size of JJ2001 is 5,443,372 bp, which contains 63.57% of G + C and has 4,547 open reading frames. Specifically, the classification of pathovar can be confirmed to be similar to that of the host lineage. Plant pathogenic factors and determinants of the majority of the secretion system are conserved in strain JJ2001. This genetic information enables detailed comparative analysis in the pathovar stage of pathogenic bacteria. Furthermore, these findings provide basic data for the distribution and diagnosis of Xanthomonas hortorum pv. carotae, a major plant pathogen that infects carrots in Korea.