• 원예과학기술지
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• 제29권1호
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• pp.48-52
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• 2011

본 연구는 시들음병균(Fusarium oxysporum f. sp. raphani)에 대한 저항성 무의 효율적인 검정법을 확립하기 위하여 수행하였다. 시들음병에 대한 저항성 반응에 차이를 보이는 무 5품종(명산무, 청두무, 장생무, 한농여름무 및 청수궁중무)을 선발하여, 뿌리 상처, 침지 시간, 접종원 농도 및 재배 온도 등의 발병 조건에 따른 무 품종들의 시들음병 발생을 조사하였다. 무 품종들의 저항성 정도를 조사하는 데는 뿌리를 자르고 접종하는 것보다 뿌리를 자르지 않고 접종하는 것이 더 효과적이었다. 그리고 이들 품종의 뿌리를 시들음병균 포자현탁액에 침지하는 시간과 접종원의 포자 농도가 증가함에 따라 시들음병 발생은 증가하였으며, $1{\times}10^7\;conidia{\cdot}mL^{-1}$의 포자현탁액에 0.5시간 침지하였을 때에 저항성 품종과 감수성 품종의 시들음병 발생은 가장 큰 차이를 보였다. 또한 시들음병균을 접종한 후에 무를 재배하는 온도에 따라 품종들의 시들음병 발생은 차이를 보였으며, $25^{\circ}C$에서 재배하였을 때 감수성 품종들은 더 높은 발병도를, 저항성 품종은 더 낮은 발병을 나타냈다. 이상의 결과로부터 무 품종들의 시들음병에 대한 저항성 차이를 검정하기 위해서는 뿌리 자르기와 같은 상처를 내지 않은, 파종 후 14일된 무의 뿌리를 $1{\times}10^7\;conidia{\cdot}mL^{-1}$의 시들음병균 포자현탁액에 0.5시간 동안 침지한 후 새로운 폿트에 이식하여 $25^{\circ}C$에서 재배하는 것이 가장 효율적인 방법임을 알 수 있었다.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.109.1-109
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• 2003

From the PMMV (pepper mild mottle virus)-inducible ESTs differentially expressed in Capsicum chinense PI257284, we isolated a full-length cDNA (CcPHZF： Capsicum chinense phenazine), encoding a phenazine biosynthesis protein which catalyzes the hydroxylation of phenozine-1-carboxylic acid to 2-hydroxyphenazine-1-carboxylic acid. Phenazine compound has been known to exhibit broad-spectrum of antibiotic activity against various species of bacteria and fungus. The entire region of CcPHZF is 879 bp in length and the open reading frame predicted a polypeptide of 292 amino acids. The homolog of CcPHZF is not Present in database except clones of AC004044 and NM100203 from Arabidopsis with 58 and 59％, respectively. Genomic Southern analysis indicated that the pepper genome contains a single copy of CcPHZF. The CcPHZF was strongly induced in the pepper leaves 3 days after PMMV treatment, when HR occurs on the leaf surface. Characterization of CcPHZF is underway to investigate if the CcPHZF is related to disease resistance against pathogens.

• 농약과학회지
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• 제4권4호
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• pp.77-80
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• 2000

건강식품으로 각광 받고 있는 누에 동충하초균의 누에에 대한 병원성을 알아보기 위하여 동충하초균을 4령기잠에 접종 후 감염잠 발생율을 조사한 결과 $10^{7}/mm^{3}$ 시험구에서는 100%, $10^{6}/mm^{3}$ 시험구에서는 96%, $10^{5}/mm^{3}$ 시험구에서는 76%, $10^{4}/mm^{3}$ 시험구에서는 44%, $10^{3}/mm^{3}$ 시험구에서는 28% $10^{2}/mm^{3}$ 시험구에서는 8%의 감염율을 나타내었다. Probit법에 의한 생물검정 결과 감염효과는 $LD_{50}$ 값이 $3.78{\times}10^{3}\;spores/mm^{3}$ 로서 생물 살충제로 개발 가능성이 높았다.

• Journal of Microbiology and Biotechnology
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• 제28권11호
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• pp.1771-1781
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• 2018

The emergence of multidrug-resistant microorganisms, as well as fungal infectious diseases that further threaten health, especially in immunodeficient populations, is a major global problem. The development of new antifungal agents in clinical trials is inferior to the incidence of drug resistance, and the available antifungal agents are restricted. Their mechanisms aim at certain characteristics of the fungus in order to avoid biological similarities with the host. Synthesis of the cell wall and ergosterol are mainly targeted in clinical use. The need for new approaches to antifungal therapeutic agents or development alternatives has increased. This review explores new perspectives on mechanisms to effectively combat fungal infections and effective antifungal activity. The clinical drug have a common feature that ultimately causes caspase-dependent cell death. The drugs-induced cell death pathway is associated with mitochondrial dysfunction, including mitochondrial membrane depolarization and cytochrome c release. This mechanism of action also reveals antimicrobial peptides, the primary effector molecules of innate systems, to highlight new alternatives. Furthermore, drug combination therapy is suggested as another strategy to combat fungal infection. The proposal for a new approach to antifungal agents is not only important from a basic scientific point of view, but will also assist in the selection of molecules for combination therapy.

• 농약과학회지
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• 제13권3호
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• pp.177-184
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• 2009

동충하초 포자 현탁액을 누에에 경피 접종하고 발병경과를 관찰하여 누에의 형태적 변화와 균사체 형성 번데기의 형태 및 성분변화를 조사하였다. 누에 유충 때 발병 치사된 누에는 불완전세대를 거쳐 분생포자를 형성하고 번데기 때 병사한 번데기는 균사체를 형성하고 자낭포자를 생산하는 완전 세대의 동충하초가 되었다. 발병하지 않은 건강한 번데기와 균사체 형성 번데기의 성분변화는 유리아미노산, 구성아미노산, 지방산, 핵산물질, 모두 차이가 있었다.

• The Plant Pathology Journal
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• 제36권4호
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• pp.378-383
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• 2020

The objective of this research was introduction of chit42 to tuber mustard plants through Agrobacteriummediated transformation against white mold caused by Sclerotinia sclerotiorum. The binary plasmid pGisPEC1 was used in this study. Polymerase chain reaction analysis detected the transgene in 27 transformants with a transformation efficiency of 6.9%. Southern blot test was used to assess the copy number of transgene in tuber mustard plants. One, two, two, and two chit42-related bands were observed in the transformed lines TMB4, TMB7, TMB12, and TMB18, respectively. Enzymatic tests showed a significant increase in the activity of endochitinase in protein isolated from leaf tissues of chit42 transgenic 75-day tuber mustard lines. The pathogenicity of three pathogen isolates was tested on the leaves of transformed plans. The results of current study showed that expression of the gene chit42 in tuber mustard plants markedly reduced infection radius on the leaves 7 days after inoculation with the fungus.

• The Plant Pathology Journal
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• 제29권4호
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• pp.435-439
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• 2013

Rice blast fungus, Magnaporthe oryzae, inflicts serious damage to global rice production. Due to high variability of this fungal pathogen, resistance of newly-released rice cultivars is easily broken down. To understand the population structure of M. oryzae, we analyzed the genetic diversity of the Korean population using multilocus microsatellite typing. Eleven microsatellite markers were applied to the population of 190 rice isolates which had been collected in Korea for two decades since the 1980's. Average values of gene diversity and allele frequency were 0.412 and 6.5, respectively. Comparative analysis of the digitized allele information revealed that the Korean population exhibited a similar level of allele diversity to the integrated diversity of the world populations, suggesting a particularly high diversity of the Korean population. Therefore, these microsatellite markers and the comprehensive collection of field isolates will be useful genetic resources to identify the genetic diversity of M. oryzae population.

• Journal of Microbiology
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• 제40권3호
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• pp.245-247
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• 2002

A genomic DNA library of the fungus Trametes versicolor was constructed in a yeast integration vector which contains the URA3 gene of the budding yeast Saccharomyces cerevisiae and the gene responsible for hygromycin B resistance, and fragments acting as autonomously replicating sequences (ARSes) in the budding yeast were identified from the genomic DNA library. Sixteen recombinant plasmids from the library transformed the budding yeast Saccharomyces cerevisiae to Ura+ at high frequencies. They were maintained stably under selective conditions, but were gradually lost from yeast cells at different rates under nonselective conditions, indicating that they contain eukaryotic origins of DNA replication and exist as extrachromosomal plasmids. Base sequences of four ARS DNAs among the 16 cloned fragments revealed that all or the four contain at least one 11 bp ［(A/T)TTTA(T/C)(A/G)TTT(A/T)］consensus sequence of the budding yeast ARS.

• Journal of Microbiology and Biotechnology
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• 제14권4호
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• pp.859-862
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• 2004

An isolate of Pseudomonas putida has been found to aggressively colonize root tips and induce plant resistance to Fusarium wilt. However, P. putida mutants lacking Fe-superoxide dismutase (SOD) or both FeSOD and MnSOD activities are less competitive in root tip colonization. In the current study, the growth of an FeSOD mutant was found to be more sensitive than that of the wild-type or a MnSOD mutant to oxidative stress imposed by paraquat treatment and culturing with the soil fungus Talaromyces flavus, which generates reactive oxygen species. Also, the loss of culturability with an aging stationary-phase culture was greater for a double SOD mutant than an FeSOD mutant, while no reduction in culturability was observed with the wild-type and a MnSOD mutant under the same protracted stationary-phase conditions. Accordingly, it was concluded that FeSOD activity is the major form of SOD in P. putida and plays an essential role in survival under stress conditions when increased oxidative stress is encountered.

• The Plant Pathology Journal
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• 제34권2호
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• pp.139-142
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• 2018

Pyrenophoratritici-repentis is the causal agent of tan spot. According to their ability to produce necrosis and/or chlorosis on a set of four differential bread wheats, the isolates of this fungus are currently grouped into eight races. When durum wheat genotypes were added to the differential set, a new virulence type was identified in Algeria. The isolates showing this virulence pattern are unable to attack bread wheat while they cause necrosis in durum genotypes. In this work, characterization of those isolates was based on pathological and molecular aspects. This included inoculation of bread and durum wheat, and virulence gene analysis using PCR and sequencing. The results showed that all isolates caused a resistance on all bread wheats of the differential set, while they produced necrosis in durum. ToxA and ToxB genes were amplified in all isolates, whereas toxb was absent. Sequence analysis for both genes showed no differences with those found in the two functional genes. The presence of two genes, ToxA and ToxB, despite the absence of symptoms usually caused by their products, suggests the existence of a new homologous for these two genes yet unknown. The presence of ToxA in the isolate unable to produce necrosis in Glenlea is reported for the first time.