• 식물병연구
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• 제11권2호
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• pp.179-184
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• 2005

Nectria haematococca에 의한 착색단고추 줄기 및 과실썩음병은 착색단고추의 안정 생산에 가장 큰 장애요인이 되고 있으나 아직까지 마땅한 방제방법이 없는 실정이다. 본 연구는 착색단고추에 등록된 살균제 중 본 병해 방제에 가장 우수한 농약을 선발하고자 수행되었다. 시험에 사용한 7종의 살균제 중 프로라츠망간은 10ppm a.i.에서 병원균의 균사생장을 완벽하게 억제하였으며 다음은 터부코나졸, 가벤다가스신, 베노밀 순이었다. 병원균의 포자발아 억제효과는 크레소심메틸과 트리프록시스트로빈이 가장 높았고 다음은 프로크로라츠, 베노밀, 아족시스트로빈 등이 높았다. 이들을 락울배지에 관주하였을 약해를 발생하지 않는 최소희석농도는 살균제별로 $2,000\~4,000$배액으로 나타났는데, 터브코나졸은 16,000배액에서도 작물생장을 강력하게 억제시켜 관주처리는 할 수 없는 것으로 조사되었다. 온실포장시험 결과 프로라츠망간이 병 방제효과가 가장 우수하였으며 방제가는 89.9\%$였다. 다음은 지오판이 $80.1\%$로 높았고 아족시스트로빈과 트리프록시스트로빈은 $70\%$, 베노밀과 가벤다$\cdot$가스신은 $60\%$로 나타났다. 본 연구결과를 농가에서 직접 활용하기 위해서는 국내 및 수출대상국인 일본의 잔류허용기준을 준수할 수 있도록 관주시기와 횟수 등의 연구가 후속되어야 할 것이다.

• Mycobiology
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• 제36권3호
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• pp.167-172
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• 2008

Beef luncheon meat is one of the most popular meals in several countries in the world including Egypt. Thirty one fungal species and 3 species varieties were recovered from 30 samples of beef luncheon meat collected from different supermarkets in Qena. Alternaria, Aspergillus, Emericella, Mucor, Mycosphaerella, Penicillium and Rhizopus were the most common genera on the two types of media. From the above genera, the most prevalent species were Alternaria alternate, Aspergillus flavus, A. fumigatus, A. niger, A. terreus, Emericella nidulans, Mucor racemosus, Mycosphaerella tassiana, Penicillium chrysogenum and Rhizopus stolonifer. Screening of fungi for their abilities to produce lipase enzyme showed that, ten isolates represented 32.26% of total isolates appeared high lipase production, while sixteen isolates (51.61%) were moderate and 5 isolates (16.13%) were low producers. Aspergillus niger, Fusarium oxysporum and Nectria haematococca produced the highest amount of lipase enzyme, so these fungi were used in further studies. The incorporation of five food preservatives (Disodium phosphate, sodium benzoate, citric acid, potassium sorbate and sodium citrate) individually in the culture medium of lipase production exhibited an inhibitive effect on the mycelial growth and enzyme production by Aspergillus niger, Fusarium oxysporum and Nectria haematococca.

• The Plant Pathology Journal
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• 제21권4호
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• pp.317-321
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• 2005

Since 2000 severe rots on aerial and underground parts of paprika (Capsicum annum L.) has occurred in most surveyed glasshouses throughout the country. A total of 56 isolates of a fungus were consistently isolated from various plant parts such as fruit, stem, branch, and root collected from 16 farms in five provinces. Anamorph stage of the fungus was identified as Fusarium solani based on its morphological characteristics. However, the fungus readily produced a sexual structure of perithecia on infected plant tissues and on agar media. Since the fungus formed abundant perithecium by a single isolate, it was considered as a homothallic strain of Nectria haematococca, the teleomorph of F. solani. Irregularly globose perithecia with orange to red color formed sparsely to gregariously on dead tissues of fruits and basal stems at the late infection stage, which is a diagnostic sign for the disease. Perithecia ranged from 125 to 220 ${\mu}m$ in diameter varied among isolates. Asci enveloping eight ascospores were cylindrical and measured 60-80x8-12 ${\mu}m$. Ellipsoid to obovate ascospores are two-celled and measured 11-18x4-7 ${\mu}m$. Ascospores were hyaline, slightly constricted at the central septum, and revealed longitudinal striations that is characteristic of the species. This fungus that has never been reported in Korea has previously become a threat to paprika cultivation because of its strong pathogenicity and nationwide distribution.

• Mycobiology
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• 제36권1호
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• pp.1-9
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• 2008

Sixty three species and 5 varieties belonging to 30 fungal genera were collected from 75 soil samples. Cultivated (29 genera and 58 species + 5 var.), desert (22 and 35 + 2 var.) and saline soil (21 and 41 + 1 var.) fungi were recovered on glucose-, cellulose- and 50% sucrose-Czapek's agar at $28^{\circ}C$. The most common genera were Alternaria, Aspergillus, Emerieella, Fusarium, Mycosphaerella, Nectria and Penicillium. The most prevalent species from the three types of soils on the three types of media were Alternaria alternata, Aspergillus flavus, A. fumigatus, A. niger, A. terreus, Emerieella nidulans, Fusarium oxysporum, Myeosphaerella tassiana, Nectria haematococca and Penicillium ehrysogenum. Chaetomium globosum was in the top of fungi in producing endo-$\beta$-1,4-glucanases among the 42 tested isolates obtained from soils on cellulose-Czapek's agar. Maximum production of this enzyme by C. globosum obtained after 6 days of incubation at $30^{\circ}C$ with culture medium containing maltose as a carbon source and ammonium nitrate as a nitrogen source and pH initially adjusted to 6.

• The Plant Pathology Journal
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• 제35권3호
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• pp.234-242
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• 2019

Thirty-four strains of bacteria were isolated from Phellodendron amurense. Using Nectria haematococca as an indicator strain, the best strain, B18, was obtained by the growth rate method. The morphological, physiological and biochemical characteristics of strain B18 and its 16S DNA gene sequence were identified, and the biocontrol effect of strain B18 was assessed in pot and field tests, as well as in a field-control test. Drilling methods were used to determine the antibacterial activity of metabolites from strain B18 and their effects on the growth of pathogen mycelia and spores. The best bacteriostatic rate was 85.4%. B18 can hydrolyse starch and oxidize glucose but does not produce gas; a positive result was obtained in a gelatine liquefaction test. According to 16S DNA gene sequencing, strain B18 is Bacillus methylotrophicus (GenBank accession number: MG457759). The results of pot and field-control trials showed 98% disease control when inoculating $10^8cfu/ml$ of the strain. The disease control effect of the B18 culture liquid (concentrations of $10^8$, $2{\times}10^6$, $10^6$, $5{\times}10^5$ and $2.5{\times}10^5cfu/ml$) in the field-control test was higher than 80%, and the cure rate of the original delivery solution was 96%. Therefore, in the practical forestry production, a $2.5{\times}10^5cfu/ml$ culture liquidshould be applied in advance to achieve good control effects.

• The Plant Pathology Journal
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• 제15권1호
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• pp.44-47
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• 1999

Fungal isolates belong to Fusarium solani (perfect stage : Nectria haematococca) were isolated form pea, ginseng roots and soybean during 1995 and 1996 in Korea. Thirty-five isolates were identified as F. solani f. sp. pisi based on the morphological characteristics and their pathogenicity. Microconidia formed on the long conidiophore were ovoid or oblong sizing 5~14 x 2.5~5.0 $\mu\textrm{m}$. Macroconidia were formed on carnation leaf agar media with 4.8~5.3 x 32.0~40.7 $\mu\textrm{m}$ in size. They belonged to $\beta$-type since their 3-septate macroconidia were smaller than $5\mu\textrm{m}$ in width. Chlamydospores were smooth- or rough- walled and formed in terminal or lateral branches of hyphae, intercalary, or in chains. Most isolates were highly virulent to pea seedlings, producing dark brown or rot lesions. This is the first report of f. solani f. sp. pisi being pathogenic to pea in Korea.

• International Journal of Industrial Entomology and Biomaterials
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• 제28권2호
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• pp.71-84
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• 2014

The full-length heat shock protein 88 (HSP88) complementary DNA (cDNA) of Paecilomyces tenuipes Jocheon-1 was obtained by screening the Paecilomyces tenuipes (P. tenuipes) Jocheon-1 Uni-Zap cDNA library and performing 5' RACE polymerase chain reaction (PCR). The P. tenuipes Jocheon-1 HSP88 cDNA contained an open reading frame (ORF) of 2,139-basepair encoding 713 amino acid residues. The deduced amino acid sequence of the P. tenuipe s Jocheon-1 HSP88 cDNA showed 77% identity to Nectria haematococca HSP88 and 45-76% identity to other fungal homologous HSP88s. Phylogenetic analysis and BLAST program analysis confirmed that the deduced amino acid sequences of the P. tenuipes Jocheon-1 HSP88 gene belonged to the ascomycetes group within the fungal clade. The P. tenuipes Jocheon-1 HSP88 also contained the conserved ATPase domain at the N-terminal region. The cDNA encoding P. tenuipes Jocheon-1 HSP88 was expressed as an 88 kilodalton (kDa) polypeptide in baculovirus-infected insect Sf9 cells. Under higher temperature conditions for the growth of the entomopathogenic fungus, mRNA expression of P. tenuipes Jocheon-1 HSP88 was quantified by real time PCR (qPCR). The results showed that heat shock stress induced a higher level of mRNA expression compared to normal growth conditions.