• Research in Plant Disease
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• v.27 no.3
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• pp.91-98
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• 2021

The current social demand for organic, sustainable, and eco-friendly approaches for farming, while ensuring the health and productivity of crops is increasing rapidly. Biocontrol agents are applied to crops to ensure biological control of plant pathogens. Research on the biological control of white root rot disease caused by a soil-borne pathogen, Rosellinia necatrix, is limited in pears compared to that in apple and avocado. This pathogenic fungus has an extensive host range, and symptoms of this disease include rotting of roots, yellowing and falling of leaves, wilting, and finally tree death. The severity of the disease caused by R. necatrix, makes it the most harmful fungal pathogen infecting the economical fruit tree species, such as pears, and is one of the main limiting factors in pear farming, with devastating effects on plant health and yield. In addition to agronomic and cultural practices, growers use chemical treatments to control the disease. However, rising public concern about environmental pollution and harmful effects of chemicals in humans and animals has facilitated the search for novel and environmentally friendly disease control methods. This review will briefly summarize the current status of biocontrol agents, ecofriendly methods, and possible approaches to control disease in pear orchards.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.5
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• pp.585-595
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• 2021

Even though most of aquatic animal pathogens are considered opportunistic and many pose a low direct risk to personnel, all personnel working with aquatic pathogens and facilities using these organisms must comply with the regulation to prevent the release of the pathogen into the environment and causing disease in aquatic animals. First of all, in order to establish a biosafety system for aquatic pathogen, the list of microorganisms that can infect aquatic animals and humans should be drawn up according to the microorganisms encountered within national boundaries. Second, risk assessment guideline for diseases of livestock and aquatic environment is desperately needed. Third, microorganisms should be classified into risk group based on their potential impact on human and aquatic environment. Fourth, facilities handling aquatic pathogens should ensure that these pathogens are securely contained and safely handled for experimental or commercial development purposes. In conclusion, classification is based on the pathogenicity, mode of transmission and host range of the aquatic microorganisms, availability of effective preventative measures and treatments. Furthermore, risk group of aquatic pathogens should be correlated with physical containment facility requirements according to domestic characteristics.

• Mycobiology
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• v.49 no.2
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• pp.173-182
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• 2021

Recently, Cryptococcus pseudolongus has been reported as a new pathogen of shiitake (Lentinula edodes). However, its pathological properties are not much known. To further understand its impact on the mushroom, we investigated the pathogen's interactions with the mycelium of shiitake, histopathological properties, host range, and sensitivity to diverse antifungal agents. The strain C. pseudolongus DUCC 4014 inhibited the mycelial growth of L. edodes strain (cultivar Sanjo 701ho) and caused browning in the mycelia confronted with the yeast on PDA. Spray inoculation of the yeast caused an abnormal browning symptom on the cap and/or gills of three shiitake cultivars grown on sawdust media in vinyl bags. Scanning electron microscopic images of the abnormally browned parts of shiitake fruit body illustrated that mushroom tissues were loosed and dispersed in the middle and edge of the cap and the arrangement of basidiospores borne on basidia in the gills was disturbed compared to those of normal shiitake fruit body. Spray inoculation also led to developing abnormal browning on the harvested fruit body, indicating C. pseudolongus could be a problem during mushroom storage. But the yeast was not able to induce abnormal browning on mushrooms of Pleurotus ferulae, Pleurotus fostreatus, and Agaricus bisporus. But it induced browning only on button mushroom (A. bisporus) when they were inoculated after wounding. Tests with 16 kinds of fungicides revealed that the cell growth of C. pseudolongus could be inhibited by benzalkonium chloride at MIC 7 ㎍/ml and benomyl at MIC 3 ㎍/ml.

• Microbiology and Biotechnology Letters
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• v.50 no.4
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• pp.457-464
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• 2022

A public health concern emerging from a zoonotic disease. Monkeypox is caused by the orthopoxvirus specie Monkeypox virus (MPXV). Monkeypox was identified as the most common orthopoxvirus infection in humans following the eradication of smallpox. Monkeypox has a similar clinical presentation to smallpox. The MPXV is now considered a high-threat pathogen that causes a serious public-health problem. The continuous spread of Monkeypox virus from West Africa to all other places around the world throughout 2018 to 2022, have raised concerns that MPXV could have emerged to acquire the immunological and ecological niche vacated by smallpox virus. This review highlights the current knowledge about Monkeypox evolution, infection biology, and epidemiology around the world since from 1970 to 2022, with a focus on the human, viral, and cellular factors that influence virus emergence, infection, spread, and maintenance in nature. This paper also discusses the current therapeutic options for Monkeypox treatment and control. Under the right conditions, with limited smallpox vaccination and very little orthopoxvirus immunity in some areas of the world, MPXV could become a more efficient human pathogen. Finally, the review identified knowledge gaps, particularly in terms of identifying a definitive reservoir host for monkeypox and proposes future research endeavors to address the unanswered questions.

• Journal of Life Science
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• v.21 no.2
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• pp.227-234
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• 2011

The hrp gene cluster in the plant pathogen Pseudomonas syringae is a key determinant of pathogenicity. Recent studies have demonstrated that specific host cell induction of the Ralstonia solanacearum hrp gene cluster is controlled by the PrhA (plant regulator of hrp) receptor. To characterize the role that P. syringae PrhA plays in the virulence of plant cells, a prhA homolog was isolated from P. syringae pv. tabaci and a $\Delta$prhA mutant was constructed by allelic exchange. The $\Delta$prhA mutant had reduced virulence in the host plant, and co-culture of P. syringae pv. tabaci and plant cell suspensions induced a much higher level of hrpA gene transcription than culture in hrp-inducing minimal medium. These results indicate that PrhA of P. syringae is a putative pathogen-plant cell contact sensor, therefore, we used a hrpA-gfp reporter fusion to monitor the in situ expression of PrhA. The results of this study demonstrated that PrhA induces hrp gene expression in P. syringae pv. tabaci in the presence of plant cells.

• Tuberculosis and Respiratory Diseases
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• v.76 no.5
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• pp.245-248
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• 2014

Miliary tuberculosis (TB) is a rare extrapulmonary form of TB, and there have been only two reports of miliary TB associated with infection with multidrug-resistant (MDR)-TB pathogen in an immunocompetent host. A 32-year-old woman was referred to our hospital because of abnormal findings on chest X-ray. The patient was diagnosed with MDR-TB by a line probe assay and was administered proper antituberculous drugs. After eight weeks, a solid-media drug sensitivity test revealed that the pathogen was resistant to ethambutol and streptomycin in addition to isoniazid and rifampicin. The patient was then treated with effective antituberculous drugs without delay after diagnosis of MDR-TB. To the best of our knowledge, this is the first case of miliary TB caused by MDR-TB pathogen in Korea.

• The Plant Pathology Journal
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• v.35 no.6
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• pp.575-584
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• 2019

Colletotrichum acutatum is a species complex responsible for anthracnose disease in a wide range of host plants. Strain C. acutatum KC05, which was previously isolated from an infected pepper in Gangwon Province of South Korea, was reidentified as C. scovillei using combined sequence analyses of multiple genes. As a prerequisite for understanding the pathogenic development of the pepper anthracnose pathogen, we optimized the transformation system of C. scovillei KC05. Protoplast generation from young hyphae of KC05 was optimal in an enzymatic digestion using a combined treatment of 2% lysing enzyme and 0.8% driselase in 1 M NH₄Cl for 3 h incubation. Prolonged incubation for more than 3 h decreased protoplast yields. Protoplast growth of KC05 was completely inhibited for 4 days on regeneration media containing 200 ㎍/ml hygromycin B, indicating the viability of this antibiotic as a selection marker. To evaluate transformation efficiency, we tested polyethylene glycol-mediated protoplast transformation of KC05 using 19 different loci found throughout 10 (of 27) scaffolds, covering approximately 84.1% of the entire genome. PCR screening showed that the average transformation efficiency was about 17.1% per 100 colonies. Southern blot analyses revealed that at least one transformant per locus had single copy integration of PCR-screened positive transformants. Our results provide valuable information for a functional genomics approach to the pepper anthracnose pathogen C. scovillei.

• The Plant Pathology Journal
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• v.36 no.6
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• pp.618-627
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• 2020

Although limited progress have been made about pathogen system of Hibiscus rosa-sinensis and Hibiscus latent Fort Pierce virus (HLFPV), interaction between plant host and pathogen remain largely unknown, which led to deficiency of effective measures to control disease of hibiscus plants caused by HLFPV. In this study, infection of HLFPV in Hibiscus rosa-sinensis was firstly confirmed for the first time by traditional electron microscopy, modern reverse transcription polymerase chain reaction and RNA-seq methods in China (HLFPV-Ch). Sequence properties analyzing suggested that the full-length sequences (6,465 nt) of HLFPV-Ch had a high sequence identity and a similar genomic structure with other tobamoviruses. It includes a 5'-terminal untranslated region (UTR), followed by four open reading frames encoding for a 128.5-kDa replicase, a 186.5-kDa polymerase, a 31-kDa movement protein, 17.6-kDa coat protein, and the last a 3'-terminal UTR. Furthermore, HLFPV-Ch-derived virus-derived siRNAs (vsiRNAs) ant its putative target genes, reported also for the first time, were identified and characterized from disease Hibiscus rosa-sinensis through sRNA-seq and Patmatch server to investigate the interaction in this pathogen systems. HLFPV-Ch-derived vsiRNAs demonstrated several general and specific characteristics. Gene Ontology classification revealed predicted target genes by vsiRNAs are involved in abroad range of cellular component, molecular function and biological processes. Taken together, for first time, our results certified the HLFPV infection in China and provide an insight into interaction between HLFPV and Hibiscus rosa-sinensis.

• Research in Plant Disease
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• v.25 no.1
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• pp.1-7
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• 2019

The rice blast fungus, Magnaporthe oryzae, is one of the most economically important crop diseases. In addition, rice-M. oryzae interaction is a classical gene-for-gene host-pathogen system. Race variation in pathogen groups was proposed as the main mechanism for rapid break-down of resistance in newly introduced rice cultivars. These new pathogen race variations may be caused by changes in an avirulence gene, such as (i) point mutations, (ii) insertion of transposons, and (iii) frame shifts. The avirulence gene AVR-Pita1 is representative avirulence gene in which all of these mutations are reported. In this review, we present a useful information for avirulence gene AVR-Pita1 and its homologous genes AVR-Pita2 and AVR-Pita3. We also review examples that cause mutations in these evolutionarily significant genes.

• Journal of radiological science and technology
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• v.45 no.3
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• pp.233-239
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• 2022

In the radiology department, where radiation is used in medical institutions to perform examinations with various equipment, the field of surgical treatment is the intervention angiography room. Accordingly, strict infection control is required. The purpose of this study was to determine the contamination status by detecting pathogens before and after disinfection in the intervention angiography room, and to determine the degree of death by using a disinfectant, sodium dichloride isocyanurate, which is mainly used in the intervention angiography room. The subjects were 10 medical institutions of general hospital level or higher with an intervention angiography room in the P city, and 12 places with high contact frequency during examinations and procedures were sampled and requested to an analysis institution. As for the sample collection method, up/down, left/right directions were used to increase precision. Before disinfection, all procedures were completed, and after disinfection, exposure was performed using a disinfectant for at least 10 minutes, and detection was performed using a transport medium. As a result, in the pathogen analysis, most pathogens were detected in a humid environment or in a place with high contact frequency for microorganisms to thrive. The detected pathogens were found in the general environment or were human flora. It is a pathogen that does not cause disease under normal healthy host conditions. However, it was found to be an opportunistic infection that causes opportunistic infection depending on the case or situation in which the body's resistance is weakened. In addition, as a result of using the disinfectant mainly used in the intervention angiography room, it was found that more than 93.3% of them died. Therefore, the data of this study will be used as good basic data for the evaluation of pathogens in the intervention angiography room and will be of great help in infection control.