• Korean Journal Plant Pathology
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• v.11 no.1
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• pp.53-60
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• 1995

Inoculation with the compatible strain Ds 1 of Xanthomonas campestris pv. vesicatoria caused brownish ad water-soaked lesions, but incompatible strain Bv5-4a produced hypersensitive symptoms with local necrosis on tomato (cv. Kwangyang) leaves. Bacterial populations of the compatible strains Ds 1 propagated more greatly than the incompatible strain Bv5-4a at the frist onset, but no differences were observed 5 days after inoculation. The bacterial infection induced the synthesis and accumulation of soluble proteins in tomato leaves, especially in the incompatible interaction. Native-polyacrylamide gel electrophoresis distinguished the soluble proteins in the tomato leaves infected by the compatible or incompatible strains. A protein of low molecular weight occurred only in the incompatible interaction. Some pathogenesis-related (PR) proteins, especially the 15, 18, 23, 26 and 54 kDa proteins, were detected only in the infected tomato leaves. In the two-dimensional electrophoresis, some proteins with different molecular weights (Mr. 21∼29 kDa) and the pI 8∼9 appeared more distinctly only in the incompatible interaction. These data suggest that the de novo synthesis of some PR proteins in tomato may be significant in defense against X. c. pv. vesicatoria.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.1
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• pp.17-21
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• 2001

Soybean mosaic virus (SMV) resistance of Korean recommended soybeans was evaluated naturally and by mechanical inoculation in Suwon. Based on the differential reaction of forty-four soybean genotypes tested to nine different SMV strains, soybeans were classified into twenty-four groups. Myeongjunamulkong and Ilpumgeom-jeongkong showed a high degree of resistance to nine SMV strains, having no symptom. The other cultivars produced various reactions according to inoculation of each SMV strain: symptomless, mosaic or systemic necrosis. Only five cultivars such as Kwangankong, Eunhakong, Tawonkong, Namhaekong, Sobaegnamulkong were totally susceptible to every strain. There was variation in disease incidence. Soybeans, having the highest levels of resistance to G5H and G7H in the greenhouse, showed the lowest levels of SMV incidence in the field of Suwon. Myeong-junamulkong, Ilpumgeomjeongkong, Soyangkong, Pungsannamulkong, Sodamkong, Jangmikong, Geomjeong-kong2, Pureunkong, Sinpaldalkong2, Duyoukong, and Geumgangkong were fairly resistant to SMV. And SMV incidence of Taekwangkong, Saealkong and Baegunkong was over 45% with symptom of bud necrosis. And soybeans, highly resistant to SMV in the field and the greenhouse, were mainly derived from Jangyeobkong and Hwang-keumkong resistant to G1-G7.

• Korean Journal of Microbiology
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• v.4 no.2
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• pp.5-10
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• 1966

The relationships between tumor score and peroxidase activities of tomato stems infected with Agrobacterium tumefaciens strain A6Kl, B6, T372 11BNV6, 11BV7 and wounded stem as a control were examined in relation to crown gall tumor development on purpose to study the lignification of tumor tissue which is affected to the development of crown gall tumor. As the previous paper has been mentioned the fact that the induction of tumor tissues were inhibited or limited in the lignified stem of host plant. It was presumed that the activities of peroxidase related to the development of lignification were decreased during the period of tumor development. But the experimental result in this experiment shows that the peroxidase activities of crown gall tumor-tissues infected with the A. tumefaciens strains which are already known as virulent are increasing during four weeks, however, in the strain 11BNV6 and wound the peroxidase activities are decreasing on the second week after the inoculation of the bacteria strains. These results could be explained on the basis of that possible regulatory agents of lignification which were accumulated in tumor tissues, IAA, ascorbic acid, glutathion(GSH) and caffeic acid esters, were postulated to act as antioxidants which has been suggested by Stafford. Total nitrogen contents in relation to crown gall tumor development were determined for the detection of protein synthesis related to the enzyme activities which are increasing in the time of plant growth. Generally six groups are contained the largest amount of nitrogen on the second week after the inoculation of the bacterium. Comparing to the tumor score, it is presumed that the all of enzyme activities including peroxidase in tumor tissues are increasing from the second week through the third week after the inoculation of bacterium and the protein synthesis is stimulated under the most appropriated temperature during the above periods.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.2
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• pp.245-253
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• 2020

Objective: To develop the fermentation quality and chemical composition of alfalfa (Medicago sativa Lam.) silage, plants were inoculated with different lactic acid bacteria (LAB) strains at field 24 hours before harvest. Methods: The treatment groups were as follow: silage without additive as a control and inoculated with each strains of Lactobacillus brevis (LS-55-2-2), Leuconostoc citerum (L. citerum; L-70-6-1), Lactobacillus bifermentans (L. bifermentans; LS-65-2-1), Lactobacillus plantarum (L. plantarum; LS-3-3) and L. plantarum (LS-72-2). All the silages were stored at 25℃. Parameters such as pH, microorganism and volatile fatty acid contents, crude protein, neutral detergent fiber, acid detergent fiber, net gas, metabolizable energy, organic matter digestibility, dry matter intake and relative feed value were measured to determine fermentation quality, chemical compositions and relative feed value of alfalfa silages. Results: Significant differences were found among the control and treated groups in terms of pH and microorganism contents at all opening times and crude protein, net gas, metabolizable energy and organic matter digestibility of final silage. The pH values ranged from 4.70 to 5.52 for all treatments and control silage had the highest value of overall treatments at T₇₅d silages. Volatile fatty acid of silages was not influenced significantly by inoculations. However, lactic acid content of L. bifermentans (LS-65-2-1) was higher than the other treatments. The highest metabolizable energy and organic matter digestibility were recorded from L. citerum (L-70-6-1) inoculation. In addition, no significant differences were found among treatments in terms of neutral detergent fiber, acid detergent fiber, dry matter intake and relative feed value. Conclusion: Among the treated LAB isolates, L. bifermentans came into prominence especially in terms of organic acid composition and quality characters of silages.

• Korean Journal of Soil Science and Fertilizer
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• v.20 no.3
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• pp.269-274
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• 1987

A laboratory experiment was conducted to find out the effect of inoculation with plant growth of associative $N_2$-fixing bacteria on the combination of eight different rice seedling with seven different associative $N_2$-fixing bacteria in which were isolated and identified from grasses and rice in saline and reclaimed saline paddy soil. Those were examined in N-free axenic culture medium. The result of this experiment exemplified the contribution of associative $N_2$-fixing bacteria to their host plant were varied much by the combination of rice cultivars and bacterial strains. Acetylene reduction ($N_2$-fixation) activity seems to be more variable with respect to the combination of rice cultivars and bacterial strains. The relationship between acetylene reduction activity and rice performance such as dry matter weight, plant height, root length, and number of root were statistically insignificant. However, in comparision with the control, the dry matter yield of Annapuruna was increased by inoculation of all the seven bacteria strains. Among the seven rice cultivars, the average acetylene reducing activity was the highest in Annapuruna, and Shingwang, and the lowest in IR-8 inoculated with Pseudomonas sp H8. Among the seven bacterial strains the highest acetylene reducing activity was obtained by the combination of Shingwang with Pseudomonas sp H8.

• Korean Journal of Veterinary Service
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• v.21 no.2
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• pp.141-148
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• 1998

Eighteen strains of Clostpidium perfringens were isolated from the piglets with hemorrhagic enteritis. The characteristics of the outbreaks, clinical signs and lesions were examined. The biochemical properties, type of toxins and susceptibility to antimicrobial agents against the isolates were investigated. 1. The incidence of diarrhea was appeared in 97(22.4%) of 432 piglets examined. 2. The isolation rate of Cl perfingens from the 97 diarrheal faeces were 18.5%(18 strains) 3. The population of Cl perfingens in feces were ranged $10^{8-9}$cfu/g in 5(32.5%) and $10^{3-7}$cfu/g in 13(67.4%) of 18 samples. 4. The toxin type of the 18 isolates investigated by mouse inoculation test was all type C strains of Cl perfringens. 5. As a results of antimicrobial susceptibility test, 18 isolates were higly susceptible to cephalothin, tetracycline and penicillin.

• The Plant Pathology Journal
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• v.31 no.4
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• pp.334-342
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• 2015

Two fumonisin-nonproducing strains of Fusarium verticillioides and their fumonisin producing progenitors were tested for aggressiveness toward maize, sorghum, rice, and beetroot seedlings grown under greenhouse conditions. None of the plants showed obvious disease symptoms after root dip inoculation. Fungal biomass was determined by species-specific real-time PCR. No significant (P = 0.05) differences in systemic colonization were detected between the wild type strains and mutants not producing fumonisins. F. verticillioides was not detected in any of the non-inoculated control plants. The fungus grew from roots to the first two internodes/leaves of maize, rice and beet regardless of fumonisin production. The systemic growth of F. verticillioides in sorghum was limited. The results showed that fumonisin production was not required for the infection of roots of maize, rice and beet by F. verticillioides.

• Korean Journal of Food Science and Technology
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• v.41 no.4
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• pp.399-404
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• 2009

The goal of this study was to improve the quality of cheonggukjang by the optimization of the inoculation methods of the Bacillus subtilis (B. subtilis) and Lactobacillus plantarum (L. plantarum) strains. In order to optimize the mixed cultivation of B. subtilis and L. plantarum, the B. subtilis strain was inoculated into steamed soybeans after cultivation of L. plantarum. Inoculation size of B. subtilis was changed to the simultaneous inoculation method in order to stimulate the growth of the L. plantarum in cheonggukjang. The viable cell count of L. plantarum increased from $2{\times}10^7$ CFU/g to $2-6{\times}10^8$ CFU/g and B. subtilis grew to $9{\times}10^8$ CFU/g. These results showed that 2 strains were successfully able to grow in the steamed soybean for good quality of cheonggukjang by optimization of the inoculation methods. The sensory evaluation indicated that a favorable aroma and overall acceptance of cheonggukjang by the optimized mixed cultivation of B. subtilis and L. plantarum, which was relatively higher than those of cheonggukjang by single strain inoculation of B. subtilis.

• The Plant Pathology Journal
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• v.16 no.2
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• pp.110-117
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• 2000

Potato virus X (PVX-KO) showing mild mosaic and stunting symptoms on potato (Solanum tuberosum) in Kangwon area has been isolated and characterized. EM observation of the purified virus particles showed flexuous rod shape of about 520 nm in length. The coat protein (CP) of the virus had a molecular weight of 31 kDa in SDS-PAGE analysis, and the viral RNA was approximately 6.4 kb in size in denatured agarose gel electro-phoresis. In gel-immunodiffusion tests, it reacted strongly with an antiserum to common PVX from BIOREABAAG (USA). A rabbit antiserum was produced using purified virus and used for routine PVX detection by ELISA. Cultivated potatoes in Kangwon and other areas were frequently infected with PVX-KO. Both Datura stramonium and Nicotiana tabaccum cultivars developed necrotic local lesions 5 days after inoculation, and systemic mosaic symptoms with vein clearing 2 weeks after inoculation. All the features agree with the description of other PVX strains. To confirm and determine PVX strains, reverse transcription-polymerase chain reaction experiment was conducted using specific primers for viral CP. Amplified DNA fragments were cloned and sequenced. Results showed nucleotide sequence homologies of about 88 to 99% to other PVX strains. Based on CP amino acid sequence deduced from nucleotide sequences and host range studies PVX-KO is considered a member of the type X subgroup of PVX.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.1
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• pp.59-65
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• 2012

Plant growth-promoting effects of rhizobacterial inoculation obtained in pot experiments cannot always be dependably reproduced in fields. In this study, we investigated the effect of inoculation with Azospirillum brasilense and Methylobacterium oryzae, which have displayed growth promoting effects in several pot experiments, on growth and fruit yield of red pepper under field condition in a plastic-film house. Four rows spaced 90 cm apart were prepared after application of compost ($10Mg\;ha^{-1}$), and red pepper seedlings (Capsicum annum L., Nocgwang) were transplanted in each row with 40-cm space. Experimental treatments were consisted of A. brasilense CW903 inoculation, M. oryzae CBMB20 inoculation, and uninoculated control. Twelve plots, 10 plants per plot, were allotted to the three treatments with four replicates in a completely randomized design. At the time of transplanting, 50 mL of each inoculum ($1{\times}10^8cells\;mL^{-1}$) was introduced into root zone soil of each plant, and re-inoculated at 7 and 14 days after transplant. Plant growth and fruit yield were measured during the experiment. Both A. brasilense CW903 and M. oryzae CBMB20 could not promote growth of red pepper plants. All growth parameters measured were not significantly different among treatments. There were large variations in fruit yield recorded on plot basis, and no statistically significant differences were found among treatments. The failure to demonstrate the expected plant growth promoting effect of the inoculants is possibly due to various environmental factors, including weather and soil characteristics, reducing the possibility to express the potential of the inoculated bacterial strains.