• Journal of Environmental Science International
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• v.32 no.11
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• pp.777-788
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• 2023

Potato common scab disease is caused by pathogens belonging to Streptomyces spp. and results in a serious yield loss worldwide. Despite decades of research aimed at disease management, a definitive control method remains undiscovered. This study aims to explore the correlation between the C/N ratio and urea application with potato common scab pathogen dynamics and disease severity. We applied sawdust with a high C/N ratio and urea into the soil prior to potato cropping, both in pot and field experiments. Disease severity assessments and quantification of the TxtB gene were conducted at the harvest stage. Furthermore, culture experiments were performed to assess the direct impact of urea on the pathogen. Our findings revealed that higher disease severity was correlated with a high C/N ratio application and pathogenic gene quantity. Urea exhibited a direct influence on S. scabiei activity, reducing the disease severity in pot experiments. However, the effects of urea application on disease suppression in the conductive field were inconclusive. Although the results of urea application experiments displayed inconsistencies between pot and field trials, urea worked as the control to suppress S. scabiei activity. Further investigations are needed under various field conditions to confirm these findings.

• 한국약용작물학회:학술대회논문집
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• 2007.05a
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• pp.125-126
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• 2007

• 한국약용작물학회:학술대회논문집
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• 2011.09a
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• pp.342-343
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• 2011

• Korean Journal of Agricultural Science
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• v.43 no.2
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• pp.153-162
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• 2016

Chilli is a widely consumed crop throughout the world. However, chilli anthracnose is a major constraint in chilli production leading to huge economic losses worldwide. Colletotrichum is a large genus of Ascomycete fungi, containing species that cause anthracnose diseases on a wide range of crops of economic value. This review is aimed at critically and accurately examining the taxonomic identification of Colletotrichum species by morphological and molecular approaches as well as assessing their management options. The use of appropriate integrated management practices, such as cultural, mechanical, chemical, and biological control, are important in chilli anthracnose disease prevention and control. Emphasis is laid on the use of biological control because it is cost effective and eco-friendly, and is an appropriate approach for disease management. The use of resistant cultivars is the cheapest, easiest, safest, and most effective means of controlling crop diseases. But, since no resistant cultivars of chilli have been developed and commercialized, it is very important to develop biological management strategies. Further studies leading to integrated disease management strategies need to be carried out.

• Mycobiology
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• v.42 no.2
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• pp.203-205
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• 2014

In 2010, symptoms of leaf and stem rot were observed on potted plants (Peperomia quadrangularis) in a greenhouse in Yongin, Korea. The causative pathogen was identified as Myrothecium roridum based on morphological data, internal transcribed spacer sequence analysis, and pathogenicity test. To our knowledge, this is the first report of M. roridum causing leaf and stem rot disease on P. quadrangularis in Korea and elsewhere worldwide.

• 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.

• The Plant Pathology Journal
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• v.26 no.4
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• pp.417-420
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• 2010

The expression of HR-like lesion inducing gene of Oryza sativa (OsHRL) was slightly increased by Xanthomonas oryzae pv. oryzae (Xoo) infection. Transgenic rice plants over-expressing OsHRL gene were challenged with Xoo and the development of disease symptoms were examined to investigate the effect of OsHRL gene expression on plant defense responses. The over-expression of OsHRL increased disease resistance against Xoo compared with wild type plants.

• The Plant Pathology Journal
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• v.25 no.4
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• pp.429-432
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• 2009

An unreported disease of apricot was observed in orchards in Zhejiang province, China. Symptoms started as water soaked lesions on the fruit surface. Later, water-soaked areas developed and spread to the entire fruit, resulting in soft rot of the whole fruit. The causal organism isolated from symptomatic fruits was identified as Burkholderia cepacia based on its biochemical and physiological characteristics and confirmed by the cellular fatty acid composition and Biolog data as well as 16S rRNA gene sequence analysis. The bacterial isolates caused similar symptoms when inoculated onto fruits of apricot. In addition, European plum, Japanese plum, nectarine and kiwifruit were susceptible to the B. cepacia pathogen. However, the B. cepacia pathogen failed to cause any visible symptoms when it was inoculated onto 16 other fruits. This is the first report of a bacterial disease of apricot caused by B. cepacia in China.

• Research in Plant Disease
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• v.18 no.3
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• pp.194-200
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• 2012

The objective of this research was to select effective fungicides for the control of Fusarium head bight (FHB) of wheat. We tested fourteen commercial fungicides against FHB in the laboratory and under field. Fludioxonil FS, Fludioxonil SC, and Benomyl + Thiram WP highly inhibited the mycelial growth of Fusarium graminearum on the medium while Oxine-copper WP, Thiophanate-methyl WP, and Copper hydroxide WP were not effective against FHB. To verify the disease control in field condition, we selected four fungicides such as Fludioxonil SC, Captan WP, Difenoconazole + propiconazole EC, and Metconazole SC. Their control efficacy on FHB disease severity of wheat was examined after the fungicide treatment twice (30th April and 10th May, 2012) in the two field locations (Iksan and Gimje). With no treatment, FHB severity was 45% and 33.7% in Gimje and Iksan, respectively. FHB disease incidence after fungicide treatment was between 0.3% and 2.2% in Gimje, showing over 95% FHB disease control. FHB disease incidence of fungicide-treated sector in Iksan showed slightly higher than Gimje but the control value of fungicides exhibited 87-90%. No side effect of the chemicals was observed in fungicide treatment. These results showed that four fungicides were effective in the FHB disease control in wheat.

• Research in Plant Disease
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• v.14 no.3
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• pp.171-175
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• 2008

The influence of rice bacterial leaf blight (BLB) disease incidence on yield and quality of Nampyung, Gang-baek and Iksan493 was investigated in three areas, Gimje, Yeongam and Jangheung, frequently found BLB infested rice. The infection rate of Nampyung, susceptible to BLB disease, was higher ($23{\sim}93%$) than Gang-baek ($2{\sim}15%$) and Iksan493 ($2{\sim}6%$), have resistant gene Xa7 and xa5, respectively. BLB disease incidence was severely found in Gimj and then yield of Nampyung was reduced 65% (352 kg/10a) compared to Iksan493 (540 kg/10a) due to the decrease in the ripen grain filling, brown/rough ratio and 1,000 grain weight. There was no difference of rice yield among Nampyung, Gangbaek and Iksan493 in Yeongam and Jangheung. The occurrence time of disease in Yeongam and Jangheung was later than Gimje and BLB disease was less infected in these areas. BLB infected rice grain showed inferior grain appearance and taste index to sound grain. independent of rice with resistant gene. In Yeongam and Jangheung, Gangbaek and Iksan493 cultivated showed lower ratio of white color to belly than Nampyung. Iksan493 showed better grain appearance and lower ratio of white core to belly than Gangbaek. In protein content of rice grain, the range of Gangbaek and Iksan493 was $6.9{\sim}9.8%$, but Nampyung showed unstable ranged from undetermined to 9.0%.