• Mycobiology
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• v.47 no.1
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• pp.66-75
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• 2019

A new species of Alternaria causing leaf spots on the rubber tree (Hevea brasiliensis) in Yunnan, China, was isolated, examined, and illustrated. Morphologically, it belongs to the section Porri of Alternaria, which produces relatively large conidia and a simple or branched, filamentous long beak. It is, however, characterized by conidiophores gradually enlarging near the apex into a clavate conidiogenous cell and long ellipsoid to obclavate, smoothwalled conidia with a long filamentous beak. Molecular phylogenetic analyses based on ITS rDNA, GAPDH, and TEF1-alpha sequences demonstrate that the phytopathogen falls in the clade of the section Porri, being most closely related to A. sidae, A. sennae, A. deseriticola, A. cyamopsidis, A. rostellata, A. nitrimali, A. crassa, and A. thunbergiae.

• Journal of Microbiology and Biotechnology
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• v.26 no.7
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• pp.1311-1319
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• 2016

Alternaria brassicicola (Schwein.) invades Brassicaceae and causes black spot disease, significantly lowering productivity. Mitogen-activated protein kinases (MAPKs) and their upstream kinases, including MAPK kinases (MAPKKs) and MAPKK kinases (MAPKKK), comprise one of the most important signaling pathways determining the pathogenicity of diverse plant pathogens. The AbSte7 gene in the genome of A. brassicicola was predicted to be a homolog of yeast Ste7, a MAPKK; therefore, the function was characterized by generating null mutant strains with a gene replacement method. AbSte7 replacement mutants (RMs) had a slower growth rate and altered colony morphology compared with the wild-type strain. Disruption of the AbSte7 gene resulted in defects in conidiation and melanin accumulation. AbSte7 was also involved in the resistance pathways in salt and oxidative stress, working to negatively regulate salt tolerance and positively regulate oxidative stress. Pathogenicity assays revealed that AbSte7 RMs could not infect intact cabbage leaves, but only formed very small lesions in wounded leaves, whereas typical lesions appeared on both intact and wounded leaves inoculated with the wild-type strain. As the first studied MAPKK in A. brassicicola, these data strongly suggest that the AbSte7 gene is an essential element for the growth, development, and pathogenicity of A. brassicicola.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47
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• pp.200-215
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• 2002

There are some international standards and organization controling the quality characteristics of varieties and seeds such as UPOV, OECD, ISTA, AOSA. The National List system to check variety performance such as quality characteristics of plant varieties and seeds was established by each countries. The UPOV (International Union for the Protection of New varieties of Plant) regulates the requirement of plant variety protection that is distinctness (D), uniformity (U), stability (S) (here in after called DUS), Novelty and Denomination, and some quality characteristics are used to examine the requirement of plant variety protection by each crops. OECD (Organization for Economic Cooperation Development) seed scheme regulates the seed certification for seed trade between countries. ISTA (International Seed Testing Association) and AOSA(Association for Official Seed Analyst) regulates the seed analysis standard and methods. Most of the countries in Europe has the National List system, which check the value for cultivation and use(VCU), that is to say, variety performance such as yield, quality and stress to environment. All the seeds should be enlisted in the National List before sell the seed in their country. All the quality characteristics checked variety performance are for instance, amylose and amylopectin content in rice, molting quality, $\beta$-glucan, protein in barley, protein and sugar content in soybean, sugar and amylopectin content in corn etc. Conditions for the protection of new variety of plant are DUS. Quality characteristics may be the important characteristics and used to check DUS in crop by crop. It is very important to develop a new characteristics and establish standard method fur examine the VCU and DUS test for each crop.

• Research in Plant Disease
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• v.12 no.2
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• pp.103-107
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• 2006

An array of surveys was designed to improve current Pesticide Management Law and Acts by investigating farmers' usage of pesticides and by assessing applicability of Plant Protection Certificate to register local pesticide markets or related businesses. This study indicates that most farmers choose pesticide recommended by local pesticide market dealers. This survey also indicates serious misuse or overuse of pesticides by farmers probably due to inappropriate recommendations. To guarantee rational use of pesticides by the end users, most experts in the plant protection areas have realized the importance of the Certificate as a license to register the local pesticide markets. To the end, current Pesticide Management Laws and Acts need to be revised to ask pesticide-dealing workers to take the Plant Protection Certificate.

• The Plant Pathology Journal
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• v.37 no.2
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• pp.124-136
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• 2021

Bark canker, wood discoloration, and wilting of the duku tree (Lansium domesticum) along the watershed of Komering River, South Sumatra Province, Indonesia first appeared in 2013. The incidence of tree mortality was 100% within 3 years in badly infected orchards. A Ceratocystis species was consistently isolated from the diseased tissue and identified by morphological and sequence analyses of the internal transcribed spacer (ITS) and β-tubulin regions. Pathogenicity tests were conducted and Koch's postulates were confirmed. The fungus was also pathogenic on Acacia mangium, but was less pathogenic on mango. Partial flooding was unfavourable for disease development. Two described isolates (WRC and WBC) had minor variation in morphology and DNA sequences, but the former exhibited a more pathogenic on both duku and acacia. The ITS phylogenies grouped the most pathogenic isolate (WRC) causing wilting of the duku tree within the aggressive and widely distributed ITS5 haplotype of C. fimbriata.

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2002.11a
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• pp.128-128
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• 2002

• The Plant Pathology Journal
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• v.33 no.1
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• pp.21-33
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• 2017

Citrus blast caused by bacterium Pseudomonas syringae is a very important disease of citrus occuring in many areas of the world, but with few data about genetic structure of the pathogen involved. Considering the above fact, this study reports genetic characterization of 43 P. syringae isolates obtained from plant tissue displaying citrus blast symptoms on mandarin (Citrus reticulata) in Montenegro, using multilocus sequence analysis of gyrB, rpoD, and gap1 gene sequences. Gene sequences from a collection of 54 reference pathotype strains of P. syringae from the Plant Associated and Environmental Microbes Database (PAMDB) was used to establish a genetic relationship with our isolates obtained from mandarin. Phylogenetic analyses of gyrB, rpoD, and gap1 gene sequences showed that P. syringae pv. syringae causes citrus blast in mandarin in Montenegro, and belongs to genomospecies 1. Genetic homogeneity of isolates suggested that the Montenegrian population might be clonal which indicates a possible common source of infection. These findings may assist in further epidemiological studies of this pathogen and for determining mandarin breeding strategies for P. syringae control.

• Journal of Veterinary Science
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• v.19 no.6
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• pp.788-797
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• 2018

In many countries, vaccines are used for the prevention of foot-and-mouth disease (FMD). However, because there is no protection against FMD immediately after vaccination, research and development on antiviral agents is being conducted to induce protection until immunological competence is produced. This study tested whether well-known chemicals used as RNA virus treatment agents had inhibitory effects on FMD viruses (FMDVs) and demonstrated that ribavirin showed antiviral effects against FMDV in vitro/in vivo. In addition, it was observed that combining the administration of the antiviral agents orally and complementary therapy with vaccines synergistically enhanced antiviral activity and preserved the survival rate and body weight in the experimental animals. Antiviral agents mixed with an adjuvant were inoculated intramuscularly along with the vaccines, thereby inhibiting virus replication after injection and verifying that it was possible to induce early protection against viral infection prior to immunity being achieved through the vaccine. Finally, pigs treated with antiviral agents and vaccines showed no clinical signs and had low virus excretion. Based on these results, it is expected that this combined approach could be a therapeutic and preventive treatment for early protection against FMD.

• Mycobiology
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• v.48 no.1
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• pp.70-74
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• 2020

Sinowilsonia henryi is a rare and endangered plant, as well as an endemic species in China. In July 2018, leaf spot and blight disease was observed on S. henryi in Yichang, Hubei, China. A fungus isolated from disease tissues was identified as Gonatobotryum apiculatum based on morphology and sequence analyses of ITS and LSU regions. Phylogenetic analyses indicated that the species belongs to Dothioraceae (Dothideales). Morphologically, the species produced two distinct types of conidia from authentic media, both conidia were described here. Pathogenicity tests showed that the fungus is a pathogen causing leaf spots on S. henryi. This is the first report of leaf spot and blight disease on S. henryi caused by G. apiculatum in China.

• Nuclear Engineering and Technology
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• v.53 no.1
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• pp.121-130
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• 2021

Cascading failure is the main cause of large blackouts in electrical power systems; this paper analyzes a cascading failure in Hanbit nuclear power plant unit two (2) caused by a circuit breaker (CB) operation failure. This malfunction has been expanded to the loss of offsite power (LOOP). In this study, current practices are reviewed and then the methodologies of how to prevent cascading failures in protection power systems are introduced. An overview on the implementation of IEC61850 GOOSE messaging-based zone selective interlocking (ZSI) scheme as key solution is proposed. In consideration of ZSI blocking time, all influencing factors such as circuit breaker opening time, relay I/O response time and messages travelling time in the communication network should be taken into account. The purpose of this paper is to elaborate on the effect of cascading failure in NPP electrical power protection system and propose preventive actions for this failures. Finally, the expected advantages and challenges are elaborated.