• Proceedings of the Korean Society of Crop Science Conference
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• 2018.04a
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• pp.21-21
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• 2018

• Proceedings of the Korean Society of Crop Science Conference
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• 2018.10a
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• pp.212-212
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• 2018

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.04a
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• pp.122-122
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• 2022

• Research in Plant Disease
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• v.22 no.3
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• pp.202-207
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• 2016

Rice bacterial blight and blast are devastating rice diseases in worldwide. Riboflavin, vitamin B2, is an essential nutrient for human health, and is known to be as a growth regulator and as a plant defense activator against pathogens in plants. In this study, we investigated possibility of increasing internal vitamin B contents and inducing resistances against rice diseases by external foliar application of a riboflavin-based formulator called BioDoctor. In planta bioassay indicated that pretreatment of the foliar application of 1,000-fold or 500-fold diluted BioDoctor significantly induced disease resistance against rice blast and bacterial blight. In addition, about four fold higher levels of riboflavin contents were detected in the BioDoctor treated rice grain and stem compared to those of untreated rice. Our results indicated that foliar application of the riboflavin has a great potential to control plant diseases and to enhance internal vitamin contents in rice.

• The Plant Pathology Journal
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• v.34 no.5
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• pp.393-402
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• 2018

Rice world production is affected due to the growing impact of diseases such as bacterial panicle blight, produced by Burkholderia glumae. The pathogen-induced symptoms include seedling rot, grain rot and leafsheath browning in rice plants. It is currently recognized the entrance of this pathogen to the plant, from infected seeds and from environmental sources of the microorganism. However, it is still not fully elucidated the dynamics and permanence of the pathogen in the plant, from its entry until the development of disease symptoms in seedlings or panicles. In this work it was evaluated the infection of B. glumae rice plants, starting from inoculated seeds and substrates, and its subsequent monitoring after infection. Various organs of the plant during the vegetative stage and until the beginning of the reproductive stage, were evaluated. In both inoculation models, the bacteria was maintained in the plant as an endophyte between $1{\times}10^1$ and $1{\times}10^5cfu$ of B. $glumae.g^{-1}$ of plant throughout the vegetative stage. An increase of bacterial population towards initiation of the panicle was observed, and in the maturity of the grain, an endophyte population was identified in the flag leaf at $1{\times}10^6cfu$ of B. $glumae.g^{-1}$ fresh weight of rice plant, conducting towards the symptoms of bacterial panicle blight. The results found, suggest that B. glumae in rice plants developed from infected seeds or from the substrate, can colonize seedlings, establishing and maintaining a bacterial population over time, using rice plants as habitat to survive endophyticly until formation of bacterial panicle blight symptoms.

• Proceedings of the Plant Resources Society of Korea Conference
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• v.18 no.1
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• pp.117-117
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• 2005

• Korean journal of applied entomology
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• v.14 no.1 s.22
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• pp.7-12
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• 1975

The experiments were conducted to examine the formation of chemical resistance of Xanthomonas oryze, the causal organism of rice bacterial leaf blight, to Agrepto in the succeeding geerations. The measurements of the bacterial growth were determined with the optical density as indirect method, and the results obtained were summarized as follows. 1. The Agrepto was effective in hindering the bacterial growth in the treatment of first generation, which was added in the broth even as low concentration as 30ppm. 2. when the successive four generations were treated with same concentrations, the bacterial growth increased conspicuously with succeeding generations and this phenomenon showed remarkable in the plots treated with 30ppm than in that of 10ppm. 3. When selections were repeated at treatment of 20 ppm, increasing the concentrations of the treatment in successive generations, the resistance increased with succeeding generations. 4. There was a tendency to acquire the higher rate of resistance in the progenies which selected from the treated plot of higher concentrations in previous generation than that of low concentrations.

• Korean journal of applied entomology
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• v.17 no.1 s.34
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• pp.37-40
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• 1978

The resistance to bacterial leaf blight of Conventional varieties (chodongi, Yongcheon etc.) cultivated from 1920 to 1956 in Korea were tested by means of 5 pathotypes of causal organism Xanthomonas oryzase (Uyeda et lshiyama) DOWSON. The results of this test are: 1. Among 74 varieties, 69 varieties including 'Chodongji, Yongcheon, Aedhal, Yongsang, Daegu, Mitdhari, pungok, etc' belong to the Kinmaze group that is highly susceptible to this disease. 2. 3 varieties: Heukbal, Doipnam, Whangphan belong to the Kogyoku group. 3. 2 varieties: Namgok, Gangbukdo, show unknown reaciton to differential varieties. 4. In 69 varieties belonging to the Kinmaze group $99.5\%$ of the plants were infected by bacterial group I. $99.6\%$ in bacterial group II. $100\%$ in group III, $99.7\%$ in group IV, and $99.8\%$ in group V. 5. In 3 varieties belong to Kyogyoku group, $1.7\%$ of the plants were infected in bacterial group I. $98.8\%$ in group II, $100\%$ in group III, IV and $1.4\%$ in group V.

• Korean Journal of Plant Resources
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• v.10 no.2
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• pp.128-134
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• 1997

This study was conducted to test on the resistance of varieties bred by crossing with Asominori to bacterial leaf blight. Nakdongbyeo and Dongjinbyeo which were susceptible to HB 9011, 8 resistant varieties including Ilmibyeo derived from Asominori and Asominori, Hwangok, 13 varieties including Chukoku 45 which were resistance to HB 9011, HB 9022 and HB 9033 were used to screen their res ponce depending on the various screening methods such as the true resistance, the secondary infection resistance and the disease common field test methods, and the results are as follows: Among 13 varieties tested, 11 varieties including llmibyeo showed tme resistance to HB 9011. Less than 1.0cm of disease lesion were developed on these varieties. Disease lesion was not developed on most of the Asominori lines including Daechongbyeo against IIB9011 and 1lmibyeo was also resistance to HB 9011, on this variety disease lesion area rate was 1.2%, and 7 varieties including Hwajinbyeo showed field resistance to HB 9022. Disease lesion area rate were 19.6% on Nakdongbyeo. 15.6% on Dongjinbyeo, from 3.0% to 2.4% on Asominori lines, and 0.5% on the Asominori when screened at disease common area. Disease was not developed on Keumnambyeo. Significant correlation coefficiences were found between the results from the test methods of the true resistance, the field resistance ancl the field resistance at disease common field tests on Asominori lines, but in some cases, even the varieties on which disease lesions developed, showed field resistance to HB 9022 and HB 9033.

• The Plant Pathology Journal
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• v.34 no.4
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• pp.269-285
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• 2018

Bacterial leaf blight is a major disease of eucalypt, especially under nursery conditions. Different bacterial species have been associated with the disease in several countries, and despite its importance worldwide, it is not clear to date whether similar disease symptoms are caused by the same or by different etiological agents. In this study, 43 bacterial strains were isolated from blighted eucalypt leaves collected in different geographic areas of Brazil and inoculated onto a susceptible eucalypt clone. Polyphasic taxonomy, including morphological, physiological, biochemical, molecular, and pathogenicity tests showed that only certain strains of Xanthomonas axonopodis caused symptoms of the disease. Strains varied in their aggressiveness, but no correlation with geographic origin was observed. MLSA-based phylogenetic analysis using concatenated dnaK, fyuA, gyrB and rpoD gene sequences allocated the strains in a well-defined clade, corresponding to Rademarker's group RG 9.6. Inoculation of nineteen plant species belonging to seven botanical families with representative strain LPF 602 showed it to be pathogenic only on Eucalyptus spp, and Corymbia spp. Based on distinct biochemical and pathogenic characteristics that differentiate the eucalypt strains from other pathovars of the X. axonopodis species, here we propose their allocation into the new pathovar X. axonopodis pv. eucalyptorum pv. nov.