• Research in Plant Disease
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• v.17 no.1
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• pp.90-94
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• 2011

Bacterial leaf blight (BLB) caused by Xanthomonas oryzae pv. oryzae (Xoo) is a very serious disease in rice growing regions of the world. There are no effective ways of protecting rice from the disease. In this study, the bacteriophage (phage) mixtures infecting Xoo were investigated as biological control agent on BLB. The effects of pH, heat and ultraviolet on the stability of phages were investigated to check and increase the possibility of practical use in the field. Phages were rather stable between pH 5 and pH 10. The infectivity dropped sharply when the phages were incubated at $50^{\circ}C$ and more than 90% of the phages were inactivated after two minutes of ultraviolet treatment. The phages were stable for 7 days at the rice plant leaves, and the phages survived 10 times more than other treatments when mixed with skim milk. Although the skim milk increased the stability of the phages, the control efficacy was not effective. However, the phage mixtures reduced the occurrence of BLB when they were treated with Tecloftalam WP or Acibenzolar-S-methyl simultaneously. The results indicated that the Xoo phages could be used as an alternative control method to increase the control efficacy and reduce the use of agrochemicals.

• The Korean Journal of Mycology
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• v.24 no.3 s.78
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• pp.167-175
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• 1996

The objective of this research was to determine the effect of light quality on formation of fruit body primordia (FBPs) of Ganoderma lucidum. To achieve this 5 isolates of the fungus that develops fruit body primordia on nutrient agar media were incubated with or without continuous irradiation. The fluorescent lamps used different colors such as black light blue (BLB), pure blue (P-B), pure green (P-G), pure yellow (P-Y) and pure red (P-R). Effect of periodic light and dark exposures on FBP formation of isolate Gl-009 was investigated. The FBP formation in G. lucidum isolates was also tested under monochromatic light produced by the combination of interference filters and colored glass filters. Three isolates produced FBPs under all kinds of fluorescent lamps, whereas two induced FBPs only under visible light except for BLB fluorescent lamp. However, these isolate did not form FBPs in the dark. The FBP was formed at light intensity from 0.05 to $10.0\;{\mu}mol\;m^{-2}s^{-1}$, and begun to reduce its number as light intensity increase over $0.5\;{\mu}mol\;m^{-2}s^{-1}$. When the isolate was incubated under periodic light and dark exposures, the number and weight of FBP increased as compared with those under continuous light. Initiation of FBP requires at least 4 days of light illumination. Although isolate Gl-003 produced FBPs in a wide range of 400 to 800 nm, other four isolates had two effective regions 400 to 500 nm and 700 to 750 nm in FBP formation.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.04a
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• pp.121-121
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• 2022

• The Plant Pathology Journal
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• v.19 no.6
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• pp.301-304
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• 2003

Gamma-ray irradiation is known to induce various mutations in plants caused by chromosome alterations. This study investigated disease responses of selected gamma-ray induced rice mutants generated from seven Japonica-type rice cultivars against three plant diseases. Among the tested 22 mutants, three gain-of-function mutants and six loss-of-function mutants against rice blast were obtained, as well as three loss-of-function mutants against bacterial leaf blight (BLB). Two of the loss-of-function mutants were susceptible to both rice blast and BLB. Gain-of-function mutation has not been frequently observed in rice plants, thus, the mutants can be used to identify loci of novel genes for the regulation of disease resistant response.

• Journal of Applied Biological Chemistry
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• v.59 no.2
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• pp.99-102
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• 2016

The phototactic behavioral responses of Tribolium castaneum adults to light-emitting diodes (LEDs) of seven different wavelengths were determined under various conditions (light exposure times, light sources, and luminance intensities) and compared with those of a black light bulb (BLB) under laboratory conditions. Based on the attractive rate (%) of T. castaneum adults under optimal conditions (50 lx and an 48 h exposure time) in the dark, red LED ($625{\pm}10nm$) exhibited the highest potential attractive rate (97.8 %), followed by yellow ($590{\pm}5nm$, 68.9 %), green ($520{\pm}5nm$, 55.6 %), infrared (IR) (730 nm, 54.4 %), white (450-620 nm, 41.1 %), blue ($470{\pm}10nm$, 34.4 %), and ultraviolet (UV) (365 nm, 0.06 %) LEDs. In comparison, red LED (97.8 %) was approximately 3.4 times more attractive to T. castaneum adults than the BLB (28.9 %). These results indicate that a red LED trap could be useful to control T. castaneum adults.

• Journal of IKEEE
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• v.28 no.1
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• pp.1-5
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• 2024

To improve the performance of DRAM, it is essential to reduce sensing failures caused by mismatch in SA. Unlike flip failures, delay failures can be degraded, especially when high-speed operation is required, making it a critical consideration in the design of next-generation memory. While conventional SA operates with all transistors starting amplification simultaneously, SDSA selectively activates only two transistors that output BLB, thus alleviating offset. In this paper, we validate the superior performance of SDSA in mitigating delay failures through simulations. It was confirmed that SDSA exhibits approximately a 90 % reduction in delay failures compared to conventional SA.

• Research in Plant Disease
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• v.16 no.3
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• pp.224-231
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• 2010

Xanthomonas oryzae pv. oryzae, causal agent of bacterial leaf blight (BLB) of rice, had been collected and identified using Biolog and fatty acid analysis. Epidemics of BLB had been occurred all the times at several rice cultivating areas in Korea in 1999-2004. Most X. oryzae pv. oryzae isolated in 1999 and 2002 belonged to Korean race K1, but more than 50% of the pathogen isolated in 2003 belonged to Korean race K3. Especially, most pathogens isolated in Jeonnam and Joenbuk provinces belonged to Korean race K3. Inoculation test of near isogenic lines (NIL) of rice carrying single resistance genes against BLB showed that many isolates belonging to Korean race 1 reacted differently to diverse resistant monogenic lines of rice. Southern blot analysis also showed that the bacterial pathogens belonged to the same race had different numbers of avirulence genes. This results suggested that each Korean race type may respond to many resistance genes of rice. All the K3 races isolated in Jeonnam and Joenbuk provinces were able to cause disease on Xa3 monogenic lines of rice. Since most rice cultivars cultivated in Jeonnam and Jeonbuk were carrying Xa3 resistance genes, the bacterial pathogens isolated in Jeonnam and Jeonbuk were likely to develop to adapt to Xa3 resistance gene. Together with avirulence gene patterns of the bacterial isolates and the results of disease reaction of monogenic lines of rice to them, Korean X. oryzae pv. oryzae was classified into 19 pathotypes. This newly classified pathotypes should help the breeding of new resistance rice cultivars in Korea.

• Proceedings of the Korean Society of Crop Science Conference
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• 2021.04a
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• pp.119-119
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• 2021

• Proceedings of the Korean Society of Crop Science Conference
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• 2021.04a
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• pp.19-19
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• 2021

• Journal of Microbiology and Biotechnology
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• v.26 no.5
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• pp.938-945
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• 2016

Bacterial leaf blight (BLB) caused by Xanthomonas oryzae pv. oryzae (Xoo) is one of the most serious threats to rice production. In this study, screening of rice for resistance to BLB was carried out at two different times and locations; that is, in a greenhouse during winter and in an open field during summer. The pathogenicity of Xoo race K1 was tested on 32 Korean rice cultivars. Inoculation was conducted at the maximum tillering stage, and the lesion length was measured after 14 days of inoculation. Five cultivars, Hanareum, Namcheon, Samgdeok, Samgang, and Yangjo, were found to be resistant in both the greenhouse and open-field screenings. Expression of the plant defense-related genes JAmyb, OsNPR1, OsPR1a, OsWRKY45, and OsPR10b was observed in resistant and susceptible cultivars by qRT-PCR. Among the five genes tested, only OsPR10b showed coherent expression with the phenotypes. Screening of resistance to Xoo in rice was more accurate when conducted in open fields in the summer cultivation period than in greenhouses in winter. The expression of plant defense-related genes after bacterial inoculation could give another perspective in elucidating defense mechanisms by using both resistant and susceptible individuals.