• The Plant Pathology Journal
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• v.40 no.1
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• pp.83-97
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• 2024

Fusarium graminearum, the causal agent of Fusarium head blight (FHB) in cereal crops, employs the production of sexual fruiting bodies (perithecia) on plant debris as a strategy for overwintering and dissemination. In an artificial condition (e.g., carrot agar medium), the F. graminearum Z3643 strain was capable of producing perithecia predominantly in the central region of the fungal culture where aerial hyphae naturally collapsed. To unravel the intricate relationship between natural aerial hyphae collapse and sexual development in this fungus, we focused on 699 genes differentially expressed during aerial hyphae collapse, with 26 selected for further analysis. Targeted gene deletion and quantitative real-time PCR analyses elucidated the functions of specific genes during natural aerial hyphae collapse and perithecium formation. Furthermore, comparative gene expression analyses between natural collapse and artificial removal conditions reveal distinct temporal profiles, with the latter inducing a more rapid and pronounced response, particularly in MAT gene expression. Notably, FGSG_09210 and FGSG_09896 play crucial roles in sexual development and aerial hyphae growth, respectively. Taken together, it is plausible that if aerial hyphae collapse occurs on plant debris, it may serve as a physical cue for inducing perithecium formation in crop fields, representing a survival strategy for F. graminearum during winter. Insights into the molecular mechanisms underlying aerial hyphae collapse provides offer potential strategies for disease control against FHB caused by F. graminearum.

• Korean journal of applied entomology
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• v.10 no.1
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• pp.39-41
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• 1971

Apple bitter rot caused by Glomerella cingulata has been known to occur annually on the fruits of previously infected twigs and the trunks. This study was carried out to ensure whether the pathogen overwinters in the form of perithecium or not. Since the acervuli of the pathogen were formed in inoculated apple trees, it would be possible that the pathogen could overwinter on the twigs, Ascigerous stage was found both under the cuticle of the infected trunk and in outer layers of rotted fruits. Therefore, it could be concluded that the pathogen overwintered in the form of perithecium is a primary inoculum in next year. Ascigerous stage of the appfe bitter rot organism was observed for the first time in Korea.

• Journal of Ginseng Research
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• v.17 no.2
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• pp.148-152
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• 1993

One kind of microorganism was isolated and identified from Korean fresh, white and red ginseng, and the effect of a preservative, sodium benzoate on the microorganism and its thermal resistant propertues were studied. The results obtained were as follows. The predominant strain on ginseng and ginseng products was identified as Penicillium sp. The strain showed perithecium structure producing ascospores. The growth of the strain was slightly inhibited at 0.0571 concentration of sodium benzoate. The minimal inhibitory concentration (MIC) of sodium benzoate against the strain was 0.26%. The D value of the strain at 56, 59, $62^{\circ}C$ were 9.9, 5.0 and 4.5 min, respectively.

• Proceedings of the Microbiological Society of Korea Conference
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• 2003.05a
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• pp.51-54
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• 2003

Analysis of the Neurospora crassa genome data reveals at least 14 proteins that contain tetratricopeptide repeat (TPR) motifs. One of them shows over $60\%$ homology with SSN6 of Saccharomyces cerevisiae, a global repressor that mediates repression of genes involved in various cellular processes. Sequence analysis of its cDNA shows that it encodes a putative 102kDa protein. Mutant strains generated by RIP (repeat induced point mutation) process show four distinctive patterns of vegetative growth at various rates. They are male-fertile, yet all female-sterile and produced little or no perithecium. These results indicate that this gene is pleiotropic and involved in several cellular processes of vegetative growth, conidiation and sexual cycle. It is designated rcm-1(regulation of conidiation and morphology).

• Journal of Applied Biological Chemistry
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• v.42 no.3
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• pp.146-150
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• 1999

As a part of the integrated disease system in greenhouse, an antifungal fungus(AF1) was isolated from greenhouse soil. It exhibited strong inhibitory activites against Pythium ultimum, Phytophtora capsici, Rhizoctonia solani, Botrytis cinerea, and Fusarium oxysporum based on dual culture on 1/5 strength of potato dextrose agar between antagonistic fungus and several plant pathogens. The antagonistic fungus was identified as Chaetomium cochliodes, based on morphological characteristics; the body of the perithecium bears straight or slightly wavy, unbranched hairs, whilst the apex bears a group of spirally coiled hairs. To investigate antagonistic principles, antifungal compound was extracted and fractionated by different solvent systems. An antifungal compound was isolated as pure crystal from is culture filtrate using organic solvent extraction and column chromatography, followed by preparative thin layer chromatography. The chemical structure of the purified antifungal compound was identified as chaetoglobosin A based on the data obtained form $^1H-NMR$, $^{13}C-NMR$, DEPT 90, 135, $^1H-^1H$ COSY, $^1H-^{13}C$ COSY and EI/MS. $ED_{50}$ values of the chaetoglobosin A against P. ultimum, P. capsici, R. solani, B. cinerea and F. oxysporum were 1.98, 4.01, 4.16, 2.67 and 35.14 ppm, respectively.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.125.2-125
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• 2003

Since 2000, severe rots on aerial and underground parts of paprika( Capsicum annum L.) has occurred in most cultivation glasshouses throughout the country. Totally 169 isolates of a fungus were consistently isolated from the diseased plant tissues of fruits, stems, branches, and roots collected from 19 farms in six provinces. Anamorph stage of the fungus was identified as Fusarium solani based on morphological characteristics. However, the fungus readily produced sexual structure of perithecia on infected plant tissues and on agar medium. Since the fungus formed abundant perithecia by single isolate, it was considered as a homothallic strain of Nectria hematococn, 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 3ate infection stage, which is a diagnostic sign for the disease. Abundancy of perithecium varied among isolates and they sized 125-220$\mu\textrm{m}$ in diam. Asci enveloping eight ascospores were cylindrical and measured 60-80x8-12$\mu\textrm{m}$. Ellipsoid to obovate ascospores are two-celled and measured 11-l8${\times}$4-7$\mu\textrm{m}$. Ascospores are hyaline, slightly constricted at the central septum, and revealed longitudinal striations that is a typical trait of the species. This fungus that has never been reported in Korea previously became a threat to paprika cultivation because of its strong pathogenicity and nationwide distribution.

• The Plant Pathology Journal
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• v.17 no.5
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• pp.257-263
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• 2001

Species of the genus Orobanche are parasitic flowering plants, holoparasites, which cling to the roots of green plants. Their tiny seeds (200 x $250\mu\textrm{m}$) germinate in response to chemical stimuli produced by host and some non-host plants. Successful contact with their host leads to development of haustoria for obtaining water and food. The shoots above the ground expose flowers and disseminate seeds. Several samples of Orobanche ramosa, O. crenata, O. cernua, and O. egyptiaca were collected from different localities in Jordan. These samples showed one of the following disease symptoms: dry rot at the base of the stem; general deterioration and expanded lesion from base upward; soft tissue maceration of stem; and black rot of flower parts with incomplete maturation of the ovary and seeds. Isolation from diseased stems and seeds was made on three different mycological media. Several fungi were isolated, mainly, Fusarium spp., Alternaria alternata, Rhizoctonia sp., Dendrophora sp., Chaetomium sp., and an ascomycetus fungus with a perithecium. Pathogenicity tests showed that Fusarium spp. and Alternaria alternata attacked healthy living tissue of Orobanche spikes. These fungi caused lesions of black soft rot and complete deterioration within 5-7 days. They also attacked Orobanche seeds, arresting their germination and causing maceration of non-germinated and germinated seeds after 5-7 days of incubation. Meanwhile, Dendrophora sp. and Chaetomium sp. caused limited lesion at first, but were able to colonize the tissue as it aged and senesced. This study showed the presence of a potential endogenous pathogenic fungi in Jordan, which can be investigated as a biological control for Orobanche.

• Journal of Korean Society of Forest Science
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• v.58 no.1
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• pp.54-59
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• 1982

Powdery mildew has been observed on the several clones of Populus euramericana, P. deltoides, P. deltoides ${\times}$ P. maximowiczii in the nurseries of Chuncheongan-do and Kangwoen-do forest Research Institute in mid-October 1982. Powdery mildew fungus of Populus spp. was identified as phyllactinia guttata(Waller. ex Fr.) $L{\acute{e}}v$ which was reported as the powdery mildew fungus of Populus tomentosa Carr. Powdery mildew of Populus spp. caused by this fungus has not previously been reported in Korea. When we surveyed the occurrence of powdery mildew disease the leaves of P. deltoides R-89 were severely attacked by this fungus.

• The Korean Journal of Mycology
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• v.27 no.3 s.90
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• pp.208-210
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• 1999

Three species belong to the genus Laboulbenia were collected on Carabidae (Coleoptera) and Harpalidae (Coleoptera) from several regions of Korea. Laboulbenia anoplogenii Thaxter was collected from Stenolophus quinquepustulatus Widemann. The characters of this species are the fourth layer of receptacle consisted of two or three cells and the distal end of its posterior cell projecting upward. The thalli were produced on posterior and anterior legs of the hosts. Laboulbenia habui Terada was collected from Chlaenius variicornis Bates. This species is characterized by the basal cells of the secondary appendage composed of short-cylindrical cells, arranged alternately on a double row. The thalli were produced from the elytra and anterior abdomen of the hosts. Laboulbenia pallida Thaxter was collected from Anisodactylus signatus Panzer. This species is distinguished from other related species by the rounded tip of perithecium and the outer appendage branched on the basal cell. The thalli were produced on the posterior elytra of the hosts.

• Journal of Sericultural and Entomological Science
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• v.46 no.1
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• pp.18-22
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• 2004

For the purpose of accumulating the research outcomes on Cordyceps and retrieving them efficiently, this study was carried out to identify and standardize the key factors in cultivating Paecilomyces tenuipes and classifying characteristics of Cordyceps. The key factors in cultivating Paecilomyces tenuipes are divided into three major sections according to its stage: silkworm rearing period, cultivation period, and preservation period. Silkworm rearing and cultivation sections are divided into three sub-sections: temperature, humidity, and duration. There are other factors including rearing tools, equipment etc. The key factors in classifying characteristics of Cordyceps are divided into 14 items, 41 divisions on the basis of its general features and its taxonomic features. 14 items contain general article, host, perithecium, conidia, etc. 41 divisions are partitioned by its size and color. The classification system of Kobayasi (1940) or of Shimizu (1994) was adopted for the key factors of Cordyceps species and their anarmorphs.