• Mycobiology
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• 제33권3호
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• pp.131-136
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• 2005

Infection structures were observed at the penetration sites on the leaves of cucumber plants inoculated with Colletotrichum orbiculare using a fluorescence microscope. The cucumber plants were previously drenched with suspension of bacterial strains Pseudomonas putida or Micrococcus luteus. The plants pre-inoculated with both bacterial strains were resistant against anthracnose after inoculation with C. orbiculare. To investigate the resistance mechanism by both bacterial strains, the surface of infected leaves was observed at the different time after challenge inoculation. At 3 days after inoculation there were no differences in the germination and appressorium formation of conidia of C. orbiculare as well as in the callose formation of the plants between both bacteria pre-inoculated and non-treated. At 5 days, the germination and appressorium formation of the fungal conidia were, however, significantly decreased on the leaves of plants pre-inoculated with M. luteus at the concentration with $1.0{\times}10^7\;cfu/ml$. Furthermore, callose formation of plants cells at the penetration sites was apparently increased. In contrast, there were no defense reactions of the plants at the concentration with $1.0{\times}10^6\;cfu/ml$ of M. luteus. Similarly, inoculation P. putida caused no plant resistance at the low concentration, whereas increase of callose formation was observed at the higher concentration. The results of this study suggest that the resistant mechanisms might be differently expressed by the concentration of pre-treatment with bacterial suspension.

• 한국버섯학회지
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• 제18권3호
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• pp.208-213
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• 2020

양송이배지로부터 분리한 인산가용화균 Burkholderia contaminans PSB-A와 Burkholderia ambifaria PSB-B의 단일접종 및 동시접종에 따른 인산가용화 능력의 시너지 효과 및 상추생육효과를 조사하였다. 인산캄슘이 함유된 NBRIP 액체배지에 분리균을 접종하고 해리된 가용인산(soluble phosphorus)함량을 HPLC에 의해 분석하여 인산가용화능을 측정한 결과, 배양 3일차에 동시접종구 166.3 ㎍ mL^-1, B. contaminans 143.7 ㎍ mL^-1, B. ambifaria 127.1 ㎍ mL^-1의 순으로 나타나 두 종의 인산가용화세균간의 동시접종에 의한 시너지효과가 다소 관찰되었다. 배지 내 pH 와 잔류 glucose 함량 변화도 모든 접종구에서 배양 1 - 3일 후 pH 7.0에서 pH 4.0 수준으로 감소하였으며, glucose 함량은 초기 10 mg mL^-1 에서 4.3 mg mL^-1 수준으로 검출되어 인산가용화능과 거의 유사한 경향을 보였다. 배양여액의 유기산 분석결과 gluconic acid 약 12.3 mg mL^-1 와 malic acid 약 7.9 mg mL^-1 수준으로 가장 높게 검출되었으며, 결과적으로 두 세균이 분비하는 유기산이 배지의 pH를 감소시키고, 인산 가용화를 유도하는 주요 원인임을 확인할 수 있었다. 접종 4주 후 상추 생육차이를 조사한 결과, TCP를 첨가하지 않은 B. contaminans 접종구, B. ambifaria 접종구 와 동시 접종구에 비해 TCA 첨가한 모든 처리구에서 약 7-9% 수준의 생육증진효과가 보였으나, 단일접종과 동시접종구간에 유의수준의 차이를 확인할 수 없었다.

• 미생물학회지
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• 제4권2호
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• pp.1-4
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• 1966

As a part of studies of plant tumor induction, this experiment was prepared for the purpose of studying the ability of tumor induction and the tendency of tumor initiation in some Korean plants using the various Agrobacterium tumefaciens strains. Results obtained from this experiment are as follows. The virulences of five strains used in this experiment were gradually decreased in order of strain A6Kl, B6, 11BV7, T37 and 11 BNV6. Especially strain T37 which is known to the host limited strain showed virulent effect to the most of plants given for the materials as well as strain A6Kl, B 6 and 11BV7. Concerning the grade of tumor development, in plants which has tough stem, for example, Glycine max Meer, tumor induction was not well developed after the inoculation of all strains. Particullary in Ricinus communes Linne all strains showed virulent effect but tumor tissues were declined in relation to the development of lignification. It was also confirmed that the induction of tumor tissues on plants is to delay according to the increase of the age of host plants.

• Journal of Microbiology and Biotechnology
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• 제28권6호
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• pp.938-945
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• 2018

Salinity stress is an important environmental problem that adversely affects crop production by reducing plant growth. The impacts of rhizobacterial strains to alleviate salinity stress on the germination of Lactuca sativa and Raphanus sativus seeds were assessed using different concentrations of NaCl. Plant growth-promoting rhizobacteria (PGPR) strains were also examined to improve the early germination of Chinese cabbage seeds under normal conditions. Lactobacillus sp. and P. putida inoculation showed higher radicle lengths compared with non-inoculated radish (Raphanus sativus) seeds. LAP mix inoculation increased the radicle length of lettuce (Lactuca sativa) seedlings by 2.0 and 0.5 cm at salinity stress of 50 and 100 mM NaCl concentration, respectively. Inoculation by Azotobacter chroococcum significantly increased the plumule and radicle lengths of germinated seeds compared with non-inoculated control. A. chroococcum increased the radicle length relative to the uninoculated seeds by 4.0, 1.0, and 1.5 cm at 50, 100, and 150 mM NaCl concentration, respectively. LAP mix inoculation significantly improved the radicle length in germinated radish seeds by 7.5, 1.3, 1.2, and 0.6 cm under salinity stress of 50, 100, 150, and 200 mM NaCl concentration, respectively. These results of this study showed that PGPR could be helpful to mitigate the salinity stress of different plants at the time of germination.

• 한국식품영양학회지
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• 제33권4호
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• pp.381-389
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• 2020

The purpose of this study was to evaluate the appearance, physicochemical, physical, and fermentation properties of the fermented soybean produced by manufacturing with inoculation the different types of microbial strains. The strains were inoculated by the NSI (natural strains inoculation), and the SSI (selective strain inoculation) were treatments. The appearance showed differences in color, viscous substance, and hardness depending on strains inoculation and fermentation duration. The pH, and total acidity were 6.40~7.26%, and 0.10~0.39% respectively with differences depending on the samples. The moisture content as the fermentation duration increased, the NSI (56.03~57.66%) decreased and the SSI (56.71~58.63%) increased. The physical characteristics of the hardness increased as the fermentation duration increased for the NSI and the SSI decreased. The color values for the L, a, and b values were 47.64~58.56, 7.15~9.08, and 12.41~17.30, respectively. The α-amylase and protease activities of the SSI were the highest among all treatments. The total viable cell counts of the fermented soybean products by strains were 5.02 to 9.77 log CFU/g, and SSI (fermentation, 48 hours) was the highest. The amino-type nitrogen contents of all samples were 301.62~746.97 mg% and the SSI showed the highest content. The amino acid had the highest glutamic acid content.

• 한국작물학회지
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• 제48권5호
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• pp.355-360
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• 2003

The responses of six mungbean [Vigna radiata (L.) Wilczek] varieties to Rhizobium inoculation on number and dry weight of nodules, nitrogenase activity of root nodule bacteria, dry weight of shoot and root, nitrogen content, and uptake by shoot were investigated. The mungbean varieties were BARI Mung-2, BARI Mung-3, BARI Mung-4, BARI Mung-5, BINA Moog-2, and BU Mung-1. Two-third seeds of each variety were inoculated with Rhizobium inoculant and the remaining one-third seeds were kept uninoculated. Rhizobium strains TAL 169 and TAL 441 were used for inoculation of seeds. Inoculation of seeds with Rhizobium strains significantly increased nodulation, nitrogenases activity, dry matter production, nitrogen content, and uptake by shoot of the crop compared to uninoculated control. There was positive correlation among the number and dry weight of nodules, nitrogenase activity, dry weight of shoot and root, nitrogen content, and uptake by shoot of the crop. It was concluded that BARI Mung-4 in association with Rhizobium strain TAL 169 performed best in recording nodulation, nitrogenase activity, dry matter production, and nitrogen uptake by shoot of mungbean.

• 한국환경농학회지
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• 제21권1호
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• pp.74-79
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• 2002

Two consecutive green house experiments were carried out to examine the effect of Azospirillum spp. inoculation on growth, nitrogen and phosphorus accumulation in maize plants grown in pots. There were eight treatments including an uninoculated control and Azospirillum strains OAD-3, OAD-9, AZ-22, AZ-8, AZ-9, Azospirillum brasilense BR-11001 and Azospirillum lipoferum BR-11080. The inoculated plants showed higher values in each of the following measurements; plant height, total dry mass and nitrogen and phosphorus accumulation in shoot when compared to the uninoculated control plants in two consecutive experiments conducted in the same soil. Among Azospirillum strains, Azospirillum sp. OAD-3 inoculated plants showed higher nitrogen accumulation by 44.5% and 45.1%, total dry mass by 48.6% and 66.9% in two consecutive experiments respectively. The nitrogen concentration in the maize plants was not changed significantly in the first experiment, however it increased significantly in the second experiment due to Azospirillum inoculation. In addition, Azospirillum sp. OAD-9 and A. brasilense BR-11001 also proved to be effective with respect to total dry mass, total nitrogen accumulation and total phosphorus accumulation. The nitrogen concentrations in maize plants were increased in the second experiment due to Azospirillum inoculation.

• 한국토양비료학회지
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• 제21권1호
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• pp.55-60
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• 1988

전국 밭토양에서 수집 분리하여 우수균주로 선발된 Rhizobium japonicum균주의 접종이 대두의 생육 및 수량에 미치는 영향등을 조사하여 대두(大豆) 생산성(生産性) 향상(向上)을 위한 근류균(根瘤菌) 접종제(接種劑)의 이용(利用) 가능성을 확인(確認)하고자 접종효과(接種效果)를 포장시험(圃場試驗)으로 실시하였다. 얻어진 결과(結果)는 다음과 같다. 1. Rhizobium균주의 접종(接種)에 의해 착생근류수(着生根瘤數) 및 근류(根瘤)무게는 질소비료 시용유무(施用有無)에 관계없이 증가하는 경향이었고 질소고정활성도 증가하였다. 2. 대두(大豆)잎중의 chlorophyll함량 변화는 질소 무시용구(無施用區)에서는 Rhizobium균주의 접종(接種)에 의해 chlorophyll함량이 증가되고 노화(老化)도 연장되는 경향이었으나 질소시용구(窒素施用區)에서는 큰 차이를 볼수가 없었다. 3. Rhizobium 균주의 접종(接種)에 의해 경장 및 절수(節數)에는 별영향을 미치지 못했으나 협수 및 지상부(地上部) 건물중이 증가하는 경향이었다. 4. 단위면적당(單位面積當) 대두수량(大豆收量)을 보면 질소무시용구(窒素無施用區)에서는 Rhizobium균(菌) 무접종구(無接種區)(337kg/10a)에 비하여 접종구(接種區)에서는 363~374kg/10a로 8~11%의 수량이 증가 되었으며 질소시용구(窒素施用區)에서는 368~384kg/10a로 질소무시용구(窒素無施用) 무접종구(無接種區)에 비해 9~14%의 수량증가가 인정되었다.

• 대한수의학회지
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• 제28권2호
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• pp.345-353
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• 1988

The present study was carried out to investigate the incidence of C jejuni and C coli in chicken. Also were examined the pathogenicity of the isolates in chick by experimental inoculation. Thermophilic Campylobacter were isolated from 34(45.9%) of the 74 specimens, and classified as 21.6% C jejuni, and 24.3% C coli. In the biotyping of 16 stranis of C jejuni isolates, 37.5% of the strains were grouped as biotype I, 62.5% as biotype II. In the case of 18 strains of C coli isolates, 49.9% of isolates were grouped as biotype I, 55.6% as biotype II. n oral inoculation with $10^4cfu$ of Campylobacter isolates into infant chicks(1 to 3 days-old), 17 days-old and 34 days-old chicks, 32.5% of the chicks developed diarrhea on day 1, 52.5% on day 3, 70.0% on day 5, and 27.5% on day 7, and the peak incidence of diarrhea was reached on day 5. The organisms were found to be discharged in feces one day afterwards. C jejuni and C coli strains were detected from the feces in 87.5% of the chicks on day 5. The organisms were multiplied from $10^4$ to $10^6cfu/gm$ in feces 5 to 7 days after inoculation. C jejuni and C coli recovered from 100% of the cecum, 64.3% of the duodenum, 50.0% of the spleen, 42.9% of the livers, and from 21.4% of gallbladders 7 days after inoculation.

• 한국수소및신에너지학회논문집
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• 제32권6호
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• pp.506-513
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• 2021

The use of fossil fuels is a major contributor to the increase atmospheric greenhouse gas emissions. As such problems arise, interest in new and renewable energy devices, particularly fuel cells, is greatly increasing. In this study, various characteristics of mixed strains were observed in wastewater collected by the Jeonju Environment Office to investigate the effects of microorganisms on voltage generation and voltage generation of substrates, electrode materials, electrons, electron transport media, and ash microbial fuel cells. As a result of separately measuring the voltage generated during inoculation, the inoculation voltage of Escherichia coli K12 (E. coli K12) was 0.45 V, and the maximum inoculation voltage of the mixed strain was 1.2 V. Thereafter, voltage values were collected using a digital multimeter and the amount of voltage generated over time was measured. In the case of E. coli K12, the maximum voltage reached 0.45 V, and the cell voltage was maintained above 0.23 V for 140 hours. In contrast, for the mixed strain, the maximum voltage reached 1.2 V and the voltage was slowly decreased to 0.97 V. In addition, the degree of microbial adsorption to the electrod surface after the inoculation test was confirmed using a scanning electron microscope. Therefore, these results showed the possibility of purifying pollutants at the same time as power generation through the production of hydrogen ions using microorganisms and wastewater.