• 한국잠사곤충학회지
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• 제17권2호
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• pp.101-118
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• 1975

가잠에 있어서 세포질 다각체 바이러스의 병원성 및 이형 바이러스 접종에 의한 유발 간섭현상을 구명하기 위하여 현장여품종인 잠103$\times$잠104의 원종과 교잡종에 있어서 육각형 및 사각형 세포질다각체 바이러스의 병원성 이형 세포질다각체 바이러스 접종에 의한 잠재성 바이러스의 활성화 및 활성화된 세포질다각체 바이러스와 접종한 세포질다각체 바이러스 사이의 간섭현상을 조사한 결과는 다음과 같다. 1. 세포질다각체 바이러스의 병원성 1) 가잠의 원종 (잠103, 잠104) 및 교잡종(잠103$\times$잠104)에 있어서 육각형 세포질다각체 바이러스의 병원성은 상호간에 고도의 유의성이 있어 교잡종이 가장 낮은 발병률을 보였고 일본종이 중간을 나타냈으며 중국종이 가장 높은 발병률을 보였다. 사각형 세포질다각체 바이러스에서도 유의성을 나타내어 있었으나 교잡종과 일본종이 같은 수준이고, 일본종과 중국종이 같은 수준이었으며, 교잡종과 중국종 사이에는 유의성이 있었다. 2) 접종령기에 따르는 병원성은 육각형 및 사각형 세포질다각체 바이러스가 다같이 고도의 유의성이 있었으며 2령기잠의 접종이 4령기잠이 접종보다 발병률이 높았다. 3) 접종된 병원체의 농도에 있어서 육각형 및 사각형 세포질다각체 바이러스의 병원성은 다같이 고도의 유의성이 있었으며, 농도가 높을수록 병원성이 높았다. 2. 이형 바이러스 접종에 의한 유발 및 간섭현상 1) 원종 및 교잡종에 있어서는 교잡종보다 원종에서 유발률이 높았으며 원종에서는 일본종보다 중국종에서 유발률이 높았다. 2) 접종 령기에 있어서는 2령기잠 접종이 4령기잠 접종보다 유발률이 높았다. 3) 사각형 세포질다각체 바이러스의 경구접종에 의한 육각형 세포질다각체 바이러스이 활성화 정도는 저농도에서 높았으며 고농도에서는 매우 낮았다. 4)육각형 세포질다각체 바이러스의 경구접종에 의한 사각형 세포질다각체 바이러스의 활성화 정도는 저농도에서는 매우 낮았으며 고농도에서는 전혀 나타나지 않았다. 5) 혼합감염은 2령기잠의 접종이 4령기잠의 접종보다 높았으며 4.2$\times$$10^{6}$/ml 농도에서 가장 높았다. 6)2령기잠에 사각형 세포질다각체 바이러스를 접종할 경우 저농도에서는 활성화한 육각형 세포질다각체 바이러스가 접종한 사각형 세포질다각체 바이러스가 활성화한 육각형 세포질다각체 바이러스를 간섭하는 것으로 생각된다. 또한 4.2$\times$$10^{6}$/ml 농도를 중심으로 개체 안에서의 육각형과 사각형 세포질다각체 바이러스 사이의 간섭현상이 평형상태를 이루는 것으로 생각된다.

• The Korean Journal of Ecology
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• 제2권1호
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• pp.15-20
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• 1978

Pathological and anatomical studies on the cause of the crown gall like symptoms associated with the chestnut nurse grafts were undertaken. The crown gall bacterium, Agrobacterium tumefaciens, was isolated from the gall tissues of chestnut nurese grafts by using selective media developed by S초개소 et al. and kado and Heskett. Typical crown gall symptoms appeared on tomato, castor bean and geranium plants 10~21 days following inoculation with the bacterium isolated from the gall tissues of chestnut nurse grafts. Agrobacterium tumefaciens was reisolated from crown gall tissues of tomato, castor bean and geranium. Anatomical studies on the origin, growth and differentiation of the gall tissues of the chestnut nurse grafts confirmed that the gall tissues are of crown gall origin. Masses of Agrobacterium tumefaciens were observed from gall tissues of chestnut nurse grafts, so it could be confirmed that the crown gall symptoms prevalent on chestnut nurse grafts are caused by the crown gall bacterium, Agrobacterium tumefaciens.

• The Plant Pathology Journal
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• 제39권2호
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• pp.181-190
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• 2023

The fungal pathogen Pseudocercospora fuligena, known to affect tomatoes in the tropics and subtropics, has been reported from temperate climates including the United States and Turkey in recent years. In this study, an isolate from fresh tomatoes and the disease it causes were characterized and infection mechanisms investigated. Macroscopically, both sides of tomato leaves show indistinct effuse patches but prolific production of fuliginous lesions is conspicuous on the abaxial side first but also on the adaxial side later on as infection progressed. Microscopically, fascicles of conidiophores (11-128 ㎛ × 3.5-9 ㎛) arising from stromata and conidia with up to 12 septations were observed. Molecular characterization of the isolate revealed high homology (99.8%) to other P. fuligena isolated from tomatoes in Turkey. Out of the 10 media tested, P. fuligena grew significantly well and sporulated better on unsealed tomato oatmeal agar and carrot leaf decoction agar, both supplemented with CaCO₃. Direct transfer of conidia from profusely sporulating lesions was the easiest and quickest method of isolation for in-vitro studies. Light and scanning electron microscopy on cleared and intact tomato leaves further confirmed stomatal penetration and egress as well as prevalence of primary and secondary infection hyphae. In situ, blocked stomatal aperture areas of 154, 401, and 2,043 ㎛² were recorded at 7, 12, and 17 days after inoculation, respectively. With the recent expanded horizon of the pathosystem and its consequential impact, such studies will be useful for a proper diagnosis, identification and management of the disease on tomato worldwide.

• 한국응용곤충학회지
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• 제14권1호
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• pp.1-5
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• 1975

본 실험은 벼흰빛잎마름병에 대한 저항성계통선발에 필요한 인공접종법 개발을 위해 시도한 것으로서 병원균의 접종농도와 식물체의 노유가 본병의 발전에 미치는 영향에 관해 중점을 두었다. 일정한 환경조건하에서 본병에 대한 식물의 감수성은 식물의 묘령이 어릴 때 일수록 예민하게 나타났으며 식물의 생장과 더불어 점차 둔감해지는 경향이었다. 파종후 14, 37, 48 및 58일째 되는 식물에서 본병에 대한 저항성과 이병성 계통을 선별할 수 있는 병원균의 적정농도는 각각 $10^6,\;10^7,\;10^7-10^{-9}$및$10^9 cells/ml.,$였다. 어린 식물에 대해 지나치게 높은 농도의 접종액은 식물의 품종에 관계없이 단시일에 고사시키는 결과를 초래하였고 묘령이 많은 식물에 대해 일정수준 이하의 세균접종농도를 적용했을 때는 식물의 품종간 특성을 구별할 수 없었다.

• 한국토양비료학회지
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• 제16권2호
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• pp.188-194
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• 1983

토양비옥도가 극(極)히 낮은 신개간지(新開墾地)에 있어서 근류균(根瘤菌)의 접종(接種) 및 비료(肥料)와 개량제 시용(施用)이 질소고정(窒素固定)과 대두수량에 미치는 영향(影響)을 밝히고자 pot시험(試驗)을 수행하였던 바 그 결과(結果)를 요약(要約)하면 다음과 같다. 1. 대두(大豆) 근류(根瘤)에 의(依)한 질소고정량(窒素固定量)은 근류균(根瘤菌)의 접종(接種)과 비료(肥料) 및 개량제 시용(施用)으로 현저히 증가하였다. 2. 근류균(根瘤菌) 접종(接種)으로 질소흡수량 및 질소고정량(窒素固定量)을 높여 콩수량을 4~10% 증대시켰다. 3. 콩 다수확재배기술체계 확립(確立)을 위하여 토양비옥도가 극(極)히 낮은 신개간지(新開墾地)에서는 개량제의 시용(施用)과 근류균(根瘤菌)과 접종(接種)이 병행되어야 할 것으로 나타났다.

• 식물병연구
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• 제16권3호
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• pp.312-315
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• 2010

본 연구는 애기장대에서 무름병에 대한 저항성 유전자를 탐색하고자 2만여개의 T-DNA 삽입 돌연변이군을 이용하여 Pcc에 대한 스크리닝을 수행하고 이 방법을 소개한 연구다. 1차 선발을 통하여 15개의 저항성 line과 20개의 감수성 line을 선발하였으며, 이로부터 2차 선발하여 3개의 저항성 line과 4개의 감수성 line을 선발하였고, 최종적으로 3차 선발을 통하여 1개의 감수성 line (Atstp1)을 선발할 수 있었다. 현재 Atstp1을 이용해 flanking sequencing 하여 유전자를 탐색하고 있으며, 앞으로 클로닝을 통하여 다양한 무름병 저항성 식물 개발에 유용하게 이용될 것으로 기대한다.

• 미생물학회지
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• 제11권4호
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• pp.167-174
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• 1973

This study included two parts of investigation, the microfloral changes during the brewing process with the changes of pH, total acidity, temperature and alcoholic contents, as well as determination of survival times of major enteric pathogens in Takju. 1. Maximum number of Saccharomyces cerevisiae was $4.3{\times}10^7$ per milliliter on the 5th day of fermentation and gradually decreased. Saccharomyces cerevisiae was one of the predominant strains of the fermentation process. The number of Saccharomyces cerevisiae was $4.3{\times}10^6$ per milliliter at the completion of the brewing and human consumption. In a few days after the completion of the brewing. Bacillus subtilis and some species of Staphylococcus spp. began to grow and those organisms were responsible for the spoilage. 2. Maximum pH, during the brewing, was 5.8 on the first day of fermentation and rapidly decreased until 6th day of fermentation at pH 4.3. 3. Maximum alcholic content was 14.5 degree on the 4th day of fermentation, 10.3 degree on the 5th day and this degree was continued during the experimentation. 4. Maximum temperature, during Takju brewing was 34.deg.C on the 3rd day of fermentation and rapidly decreased up to 23.deg.C on the 6th day and this temperature was continued until the brewing process was finished. 5. Maximum total acidity was 0.57 percent on the 4th day of fermentation and gradually decreased by brewing process was completed. 6. Survival time of major enteric pathogenic bacteria in Takju was as follows : Shigella dysenteriae and Escherichia coli were isolated in two hours and 14 hours respectively, but Salmonella typhi, Vibrio parahemolyticus were not isolated even in an hour after the inoculation of those organisms in undiluted Takju. In diluted Takju, Salmonella typhi, Vibrio parahemolyticus were not isolated even in an hour after the inoculation of those organisms in undiluted Takju. In diluted Takju, Salmonella typhi, Shigella dysenteriae, and Escherichia coli were survived for 50-60 hours, but Vibrio cholerae and Vibrio parahemolyticus were not isolated even if treated within one hour.

• Journal of Microbiology and Biotechnology
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• 제30권8호
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• pp.1195-1206
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• 2020

Beringraja pulchra, Cham-hong-eo in Korean, is a mottled skate which is belonging to the cartilaginous fish. Although this species is economically valuable in South Korea as an alkaline-fermented food, there are few microbial studies on such fermentation. Here, we analyzed microbial changes and pH before, during, and after fermentation and examined the effect of inoculation by a skin microbiota mixture on the skate fermentation (control vs. treatment). To analyze microbial community, the V4 regions of bacterial 16S rRNA genes from the skates were amplified, sequenced and analyzed. During the skate fermentation, pH and total number of marine bacteria increased in both groups, while microbial diversity decreased after fermentation. Pseudomonas, which was predominant in the initial skate, declined by fermentation (Day 0: 11.39 ± 5.52%; Day 20: 0.61 ± 0.9%), while the abundance of Pseudoalteromonas increased dramatically (Day 0: 1.42 ± 0.41%; Day 20: 64.92 ± 24.15%). From our co-occurrence analysis, the Pseudoalteromonas was positively correlated with Aerococcaceae (r = 0.638) and Moraxella (r = 0.474), which also increased with fermentation, and negatively correlated with Pseudomonas (r = -0.847) during fermentation. There are no critically significant differences between control and treatment. These results revealed that the alkaline fermentation of skates dramatically changed the microbiota, but the initial inoculation by a skin microbiota mixture didn't show critical changes in the final microbial community. Our results extended understanding of microbial interactions and provided the new insights of microbial changes during alkaline fermentation.

• 대한수의학회지
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• 제8권2호
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• pp.98-109
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• 1968

The small type piroplasma which is known to be prevailing in Korean cattle was injected to un-susceptible hosts such as mice, guinea pigs, rats, rabbits, fowls and developing chicken eggs by i.v., i.p, and intra C.A.M. routes, and its morphological development in each animal species was observed. 1. The small type piroplasma of cattle did not produce any pathogenicity in the experimental animals such as mice, guinea pigs, rats, rabbits, fowls and developing chicken embryos. However, only a partial sign for developing cycle of the organism was observed in the peritoneal fluid. The schizogony of protozoa was not detected in any organs of the inoculated animals. 2. In the animals inoculated, the parasites of I-III types, relative to the process of time in the host, have changed their shapes into IV-VI types and then VI-X types however, the type X was not restored to the type I. In guinea pigs, more grape type was detected then X type in number, and in process of time, the shape was changed from round to elliptic, and the pointed end of the organism appeared in flesh color. 3. None of the organisms were found from the blood stream of inoculated animals excepts only a few piroplasma as were found in the experimental mice shortly after inoculation or i.v. route, No protozoa was also found in the organs of the animals autopsied. 4. The form change of protozoa was more clear in these animals than that in susceptible host. The most piroplasmas have changed their forms into VI-X types 30 hours after inoculation and were dispersed from R.B.C. Tracing of piroplasrna beyond this stage was not attempted. 5. The small type piroplasma comprises in I. X types and it is further believed that VII-X types which were freed from one cell proceeded to invade others. The from of development resembles to the small type of piroplasma which is prevailing in Japan.

• 한국산림과학회지
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• 제94권3호통권160호
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• pp.146-152
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• 2005

훼손된 비탈면의 조림에 균근균의 이용가능성을 타진하기 위하여, 땅찌만가닥버섯(Lyophyllum shimeji)의 배양학적 특성 및 인공접종에 의한 참싸리(Lespedeza cyrtobotrya)에서의 균근 형성 특성을 조사하였다. L. shimeji는 MP (1% malt extract, 0.1% peptone, 1% glucose, 1.5% agar)배지에서 균사 생장이 가장 왕성하였으며, 균사 최적 배양 온도 및 pH는 각각 $25^{\circ}C$ 및 pH 6 이었다. 인공접종에 의한 참싸리에서의 균근 형성 특성을 조사한 결과, L. shimeji는 Hartig net을 형성하는 외생균근의 특성을 나타내었으며, 균근 접종 실생 묘목 뿌리의 생장율은 대조구에 비하여 우수하였다. 균근 접종 실생 묘목을 비탈면에 이식하였을 때의 생존율 및 건중량은 각각 62% 및 850 mg/본 이었으나, 균근을 접종하지 않은 실생 묘목의 생존율 및 건중량은 각각 11% 및 430 mg/본 이었다.