• The Plant Pathology Journal
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• 제33권2호
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• pp.103-108
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• 2017

World wheat production is now under threat due to the wheat blast outbreak in Bangladesh in early March 2016. This is a new disease in this area, indicating the higher possibility of this pathogen spreading throughout the Asia, the world's largest wheat producing area. Occurrence of this disease caused ~3.5% reduction of the total wheat fields in Bangladesh. Its economic effect on the Bangladesh wheat market was little because wheat contributes to 3% of total cereal consumption, among which ~70% have been imported from other countries. However, as a long-term perspective, much greater losses will occur once this disease spreads to other major wheat producing areas of Bangladesh, India, and Pakistan due to the existing favorable condition for the blast pathogen. The wheat blast pathogen belongs to the Magnaporthe oryzae species complex causing blast disease on multiple hosts in the Poaceae family. Phylogenetic analysis revealed that the Bangladesh outbreak strains and the Brazil outbreak strains were the same phylogenetic lineage, suggesting that they might be migrated from Brazil to Bangladesh during the seed import. To protect wheat production of Bangladesh and its neighbors, several measures including rigorous testing of seed health, use of chemicals, crop rotation, reinforcement of quarantine procedures, and increased field monitoring should be implemented. Development of blast resistant wheat varieties should be a long-term solution and combination of different methods with partial resistant lines may suppress this disease for some time.

• The Plant Pathology Journal
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• 제36권2호
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• pp.179-184
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• 2020

A leaf spot pathogen Alternaria sp. was recovered from jimson weed, tomato, parsley, and coriander collected during surveys of blight diseases on Solanaceae and Apiaceae in Algeria. This species produced large conidial body generating long apical beaks that tapered gradually from a wide base to a narrow tip and short conidiophores originating directly from the agar surface. This species exhibited morphological traits similar to that reported for Alternaria crassa. The identification of seven strains from different hosts was confirmed by sequence analyses at the glyceraldehyde-3-phosphate dehydrogenase, RNA polymerase second largest subunit, and translation elongation factor 1-alpha loci. Further the pathogen was evaluated on jimson weed, coriander, parsley, and tomato plants, and this fungus was able to cause necrotic lesions on all inoculated plants. A. crassa is reported for the first time as a new species of the Algerian mycoflora and as a new potential pathogen for cultivated hosts.

• 한국균학회지
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• 제46권3호
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• pp.235-239
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• 2018

Basil (Ocimum spp.) is a popular herb grown worldwide. During the past fifteen years, a downy mildew pathogen has caused considerable damage to basil cultivations. In August 2017, downy mildew disease symptoms were found on Basil Tree (or long foot Basil Tree), which was developed by the grafting of two basil varieties and is a continuous harvest plant with a woody trunk. The present study reports the occurrence of downy mildew disease in basil Tree and identifies the causal pathogen, as Peronospora belbahrii.

• Mycobiology
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• 제44권2호
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• pp.85-92
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• 2016

Mycoherbicides are exclusive biotechnology products which offer a non-chemical solution to control noxious weeds on the land as well as aquatic in systems, viz a viz saving environment from hazardous impact of synthetic chemicals. The present paper highlights the mycobiota associated with Eichhornia crassipes infesting Harike wetland area of Punjab and evaluation of their pathogenic potential for futuristic application as a mycoherbicide. Of the 20 isolates tested by leaf detached assay and whole plant bioassays, only one isolate (#8 BJSSL) caused 100% damage to E. crassipes. Further, the culture filtrate of this isolate also exhibited a similar damage to the leaves in an in vitro detached leaf assay. The potential isolate was identified as Phaeoacremonium italicum using classical and modern molecular methods. This is the first report of P. italicum as a pathogen of E. crassipes and of its potential use as a biological control agent for the management of water hyacinth.

• IMMUNE NETWORK
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• 제20권5호
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• pp.37.1-37.15
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• 2020

Mycobacterium tuberculosis (Mtb) is an etiologic pathogen of human tuberculosis (TB), a serious infectious disease with high morbidity and mortality. In addition, the threat of drug resistance in anti-TB therapy is of global concern. Despite this, it remains urgent to research for understanding the molecular nature of dynamic interactions between host and pathogens during TB infection. While Mtb evasion from phagolysosomal acidification is a well-known virulence mechanism, the molecular events to promote intracellular parasitism remains elusive. To combat intracellular Mtb infection, several defensive processes, including autophagy and apoptosis, are activated. In addition, Mtb-ingested phagocytes trigger inflammation, and undergo necrotic cell death, potentially harmful responses in case of uncontrolled pathological condition. In this review, we focus on Mtb evasion from phagosomal acidification, and Mtb interaction with host autophagy, apoptosis, and necrosis. Elucidation of the molecular dialogue will shed light on Mtb pathogenesis, host defense, and development of new paradigms of therapeutics.

• 한국균학회소식:학술대회논문집
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• 한국균학회 2015년도 춘계학술대회 및 임시총회
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• pp.29-29
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• 2015

Clubroot disease is caused by the soil-born obligate plant pathogen Plasmodiophora brassicae. This pathogen can infect all cruciferous vegetables and oil crops, including Brassica rapa, B. oleracea, B. napus, and other Brassica species. Clubroot disease is now considered to be a major problem in Chinese cabbage production in China, Korea, and Japan. We collected several hundreds of P. brassicae infected galls from Korea, and isolated the single spore from the collection. For establishment of novel isolation, and mass-propagation methods for singe spore isolates of P. brassicae pathogen, we developed new filtration method using both cellulose nitrate filter and syringe filter. Accurate detection of P. brassicae pathogen in the field was done by using real-time PCR in the potential infested soil. When we tested the different pathogenicity on commercial Chinese cabbage varieties, P. brassicae from collected galls showed various morphological patterns about clubroot symptom on roots. To date, 8 CR loci have been identified in the B. rapa genome using the quantitative trait loci (QTL) mapping approach, with different resistant sources and isolates. We are trying to develop the molecular marker systems for detect all 8 CR resistant genes. Especially for the study on the interaction between pathogens and CR loci which are not well understood until now, genome wide association studies are doing using the sequenced inbred lines of Chinese cabbage to detect the novel CR genes.

• 식물병과 농업
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• 제5권2호
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• pp.69-76
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• 1999

Acidovorax avenae subsp. avenae is the causal pathogen of several hosts including oats corn foxtail millet wheatgrass sugarcane and rice. The pathogen is a seedborne pathogen of rice and known to occur widely in rice growing countries. The pathogen cause inhibition of germination brown stripe on the leaf curling of the leaf sheath and abnormal elongation of the mesocotyl of irce. Bacterial colonies grow slowly and are convex circular and creamy with tan to brown center. The causal baterium is Gram-negative and rod shape with a single polar flagellum Nonfluorescence poly-$\beta$-hydroxybutyrate accumulation and precipitate formation around the colony on the medium are useful in the differentiation of this bacterium from other subspecies of A. avenae as well as nonfluorescent bacteria pathogenic to rice. This bacterium has belonged to the genus of Psdeudomonas but recently was transferred to the new genus Acidovorax on the basis of bacteriological and molecular biological data. However the difference of biochemical characteristics protein profile of the cell and host range among strains should be more clarified. To develop an effective control strategy for this disease understanding of detailed life cycle of the disease ritical environmental factors affecting disease development on each host and relationship to grain discoloration of rice are prerequisite. Although the affected area has been world-widely reported there is on recent progress on the understanding of the bacteriological and ecological characteristics of the causal bacterium and control means of the disease.

• Asian-Australasian Journal of Animal Sciences
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• 제15권6호
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• pp.912-924
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• 2002

Disease susceptibility is linked to nutritional status for a wide range of human and animal diseases. Nutritional status can influence both resistance (ability to resist the pathogen) and resilience (ability to tolerate or ameliorate the effects of the pathogen). This review focuses on the nutritional modulation of gastro-intestinal nematode infection in domestic ruminants, primarily sheep. It highlights the duality of the adverse consequences of infection on host nutritional status and the adverse consequences of poor host nutritional status on resistance to infection. Central to both phenomena is the complex, gut-based immune response to gastrointestinal nematode infection. The potential for strategic nutritional supplementation to enhance host resistance and resilience is reviewed together with recent findings on responses to increased ME supply, and long term effects on host immunity of short term protein supplementation.

• Mycobiology
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• 제44권4호
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• pp.335-337
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• 2016

During the growing season of 2015, leaf specimens with yellow rust spots were collected from Salix koreensis Andersson, known as Korean willow, in riverine areas in Cheonan, Korea. The fungus on S. koreensis was identified as the rust species, Melampsora yezoensis, based on the morphology of urediniospores observed by light and scanning electron microscopy, and the molecular properties of the internal transcribed spacer rDNA region. Pathogenicity tests confirmed that the urediniospores are the causal agent of the rust symptoms on the leaves and young stems of S. koreensis. Here, we report a new rust disease of S. koreensis caused by the rust fungus, M. yezoensis, a previously unrecorded rust pathogen in Korea.

• 치위생과학회지
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• 제24권2호
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• pp.84-96
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• 2024

Background: Recent studies have elucidated the quorum-sensing mechanisms, biofilm formation, inter-pathogen interactions, and genes related to oral pathogens. This review aims to explore the recent expansion of drug targets against oral pathogens and summarize the current research on novel antibiotic substances derived from marine organisms that target oral pathogens. Methods: A comprehensive literature review summarized the novel mechanisms pertaining to quorum-sensing signal transmission systems, biofilm formation, and metabolite exchange in oral pathogens. The amino acid sequences of the 16 proteins identified as potential drug targets were systematically classified and compared across various oral microorganisms. Results: Through a literature review, we identified nine studies researching quorum sensing signaling inhibitors targeting oral pathogens. A comparison of the amino acid sequences of 16 potential drug targets in oral microorganisms revealed significant differences between oral pathogens and beneficial oral symbiotic microorganisms. These findings imply that it is possible to design drugs that can bind more selectively to oral pathogens. Conclusion: By summarizing the results of recent research on the signaling mechanisms that cause pathogenicity, new drug targets against oral pathogens were proposed. Additionally, the current status of developing new antibiotics for oral pathogens using recently developed quorum sensing inhibitors and natural products derived from marine organisms was introduced. Consequently, marine natural products can be used to develop drugs targeting new proteins in oral pathogens.