• 한국잠사곤충학회지
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• 제42권2호
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• pp.99-103
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• 2000

This study was carried out to investigate incubating characteristics, LTSEM observation, nature of a disease of infected silkworms(bombyx mori), LD$\_$50/, optimum infective condition for mass production and infection percentage(%) on conservation periods. On the V8 media, the colony was 0.5∼2.0cm/8 days in diameter and white or slighty colored with a white fluffy to powdery appearance. The conidia was subglobos in shape, zig-zag appearance, 1-celled, hyaline and 3.2$\times$2.4 ㎛ in size on the average. The conidiophore was irregular grouped, hyaline, rounded or flask-shaped. The LD$\_$50/ values of the 2nd and 4th silkworms were each other 6.6142(Log) in natural temperature and humidity (25$\^{C}$, 65%). On optimum infective condition for mass production, all of preservation time(hr.) postinoculation in 1.0$\times$10$\^$8/ conidia/㎖ was over 97% and only 20 hr in 1.0$\times$10$\^$7/ condia/㎖ was over 90%.

• 한국식품과학회지
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• 제22권6호
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• pp.696-699
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• 1990

쌀을 기질로 하여 고오지 곰팡이와 Saccharomyces cerevisiae를 함께 동시 접종하여 혼합 배양에 의한 동시 당화발효를 시도하였다. Aspergillus awamori, A. kawachii, A. niger, A. oryzae 및 A. shirousamii를 각각 S. cerevisiae와 혼합배양하였을 때 A. shirousamii와의 혼합배양에서 가장 높은 주정생산량을 보였다. 이 때의 가수량은 쌀 50g에 대하여 150ml 이었다. 곰팡이와 효모는 각각 $5{\times}10^2\;conidia/ml$ 및 $5{\times}10^6\;cells/ml$로 접종한 경우에, 용적에 대한 표면적의 비는 0.1에서 그리고 초기 pH6.5 및 $30^{\circ}C$의 배양조건에서 10일 동안 발효시 최고 12.9%의 주정이 생산되었다.

• 식물병연구
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• 제30권3호
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• pp.229-235
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• 2024

식물 병원성 곰팡이의 포자는 병원성을 테스트하고 병원균의 생리 및 생태를 연구하는 데 중요한 역할을 한다. 따라서 안정적인 포자 생산을 위해서는 적절한 빛과 배지 조건은 필수적이다. 본 연구에서는 Bipolaris oryzae의 지속적인 포자 확보를 위한 조건을 확립하기 위해 슬라이드 배양법을 통해 빛 조건과 적합한 배지 조건을 조사하였다. 첫째, Bipolaris oryzae 균주 CM23-042와 23CM10을 사용하여 두 가지 서로 다른 빛 조건을 설정하였다. 첫 번째 조건은 지속적인 형광등과 근 자외선(NUV) 하에서의 포자 형성이었고, 두 번째 조건은 NUV와 암 상태를 12시간 주기로 교대로 바꿔주는 방식이었다. 둘째, 감자 포도당 한천(PDA) 배지, V8-Juice 한천 배지, 최소 배지(MM), sucrose-proline 한천 배지(SPA), 토끼 풀 한천 배지(RFA), 쌀겨 한천 배지(RBA), 벼 잎 한천 배지(RLA) 등 7가지 서로 다른 배지에서 포자 형성을 관찰하였다. 접종 후 7일이 경과한 결과, 실험에 사용된 균주 CM23-042와 23CM10은 PDA 배지에서 지속적인 형광등과 근 자외선(NUV) 조건에서만 포자 형성이 유도되었으며, 다른 조건에서는 포자가 형성되지 않았다. 또한, B. oryzae CM23-042 균주는 MM에서 가장 많은 포자를 형성한 반면, 23CM10 균주는 PDA에서 가장 많은 포자를 형성하였다. 종합적으로, 본 실험에서는 지속적인 형광등과 근 자외선을 동시에 조사하는 조건이 포자 유도에 가장 적합하다는 결과를 얻었다. 동시에, 포자 형성을 위한 배지 선택은 B. oryzae 균주에 따라 다를 수 있으나, MM과 PDA 또는 SPA와 RFA 배지의 적용이 포자 유도에 효과적일 것으로 예상된다. 본 연구 결과는 B. oryzae의 수집 균주들의 특성에 맞춰 포자 형성을 향상시키는데 기여할 것이다.

• 한국미생물·생명공학회지
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• 제19권2호
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• pp.140-146
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• 1991

Mutation experiments were performed to select the mutant of Aspergillus niger 55, which had lost almost all the ability to produce transglucosidases but retained that of high productivity of raw meal saccharifying enzyme, by means of successive induction with N-methyl-N'-nitro-N-nitrosoguanidine(MNNG), ultraviolet(UV) light, and ${\gamma}$-rays. Also, we used the mutant enrichment techniques, such as liquid culture-filtration procedure and differential heat sensitivity of conidia, in order to increase the possibility of obtaining a mutant. The glucoamylase productivity of mutant PFST-38 was 11 times higher than that of the parent strain. The mutant PFST-38 was morphologically identical to the parent strain, except for the size of conidia, the tendency to form conidia and the lenght of conidiophore. Asp. niger mutant PFST-38 apeared to be useful for the submerged production of the raw corn meal saccharifying enzyme.

• Journal of Ginseng Research
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• 제22권4호
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• pp.304-309
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• 1998

Incubation condition affecting the chlamydospore formation and isolation from mycelia and conidia of Cylindrocarpon destructanse (isolate ACY-9701), isolated from the root rot lesion of the American ginseng (Panax quinquefolium) was investigated. Chlamydospores were formed from mycilia but not from conidia on the Czapek-Dox agar without carbon or nitrogen source after 20 days incubation at 2$0^{\circ}C$. In the medium added with nitrogen and carbon sources, immatured chlamy-dospore-like cells were formed from microconidia and mycelia as well. Immatured chlamydospore-like cells were formed from mycelia as well as microconidia In corn, kidney bean, and pea root extracts after 20 days incubation at 20"C, while typical chlamydospores were formed from both of them in the root extract of Panax quinquefolium. The 3.6 log chlamydospore/mm" was converted from microconidia in the medium, which was equal to 2.5% conidia formed. Under the light condition (251.1 pmol/m" sec, 12 hrs dark and light cycle), 4.2 log/mm" of chlamydospores were converted from interracially or terminal cells of macroconidia, which was 4.0% of macroconidia produced on Potato dextrose agar (PDA). When mycelia and microconidia were stored at -7$0^{\circ}C$ for 32 days and incubated on PDA after thawing at room temperature to isolate chlamydospores from them, microconidia and mycelia were still alive. Meanwhile, microconidial lysis was found after heating them at 32$^{\circ}C$ for 7 days, but the chlamydospores converted from macroconidia were not lysed up to 13 days at 32"C. to 13 days at 32"C.ot;C.

• 한국미생물·생명공학회지
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• 제27권1호
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• pp.1-7
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• 1999

A fungus, Penicillium sp. PS-113, isolated from soil showed the high phosphate-solubilizing activity in patato dextrose broth-rock phosphate to produce free phosphates to the culture broth with the concentrations of 585 ppm against rock phosphate. In this medium, the optimum temperature and initial pH to solubilize rock phosphate were 30$^{\circ}C$ and pH 7.5, respectively. In order to make the mass production of the conidia from this fungus, we cultured in on various solid-based media like barley, corn, wheat, rice, rice bran, and compost. As a result, the fungus highly produced conidia ranging from 2.1 to $5.1{\times}10_9$ conidia/g${\cdot}$media on these solid media except compost-based medium, which was 0 times less than others. Effects of inoculation of the phosphate solubilizing fungus as a biofertilizer were studied in perlite-based pot cropped with Zea mays Suwon 19. Inoculation of Penicillium sp. PS-113 increased in plant height (1.4 times), plant weight (5.2~8.1 times) and root length (1.1~1.2 times) at 60-day cultivation, compared to Hogland solution either without $NH_4H_2PO_4$ or displace $NH_4H_2PO_4$ to powdered rock phosphate, a phosphorus source for plant growth.

• The Plant Pathology Journal
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• 제39권2호
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• pp.181-190
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• 2023

The fungal pathogen Pseudocercospora fuligena, known to affect tomatoes in the tropics and subtropics, has been reported from temperate climates including the United States and Turkey in recent years. In this study, an isolate from fresh tomatoes and the disease it causes were characterized and infection mechanisms investigated. Macroscopically, both sides of tomato leaves show indistinct effuse patches but prolific production of fuliginous lesions is conspicuous on the abaxial side first but also on the adaxial side later on as infection progressed. Microscopically, fascicles of conidiophores (11-128 ㎛ × 3.5-9 ㎛) arising from stromata and conidia with up to 12 septations were observed. Molecular characterization of the isolate revealed high homology (99.8%) to other P. fuligena isolated from tomatoes in Turkey. Out of the 10 media tested, P. fuligena grew significantly well and sporulated better on unsealed tomato oatmeal agar and carrot leaf decoction agar, both supplemented with CaCO₃. Direct transfer of conidia from profusely sporulating lesions was the easiest and quickest method of isolation for in-vitro studies. Light and scanning electron microscopy on cleared and intact tomato leaves further confirmed stomatal penetration and egress as well as prevalence of primary and secondary infection hyphae. In situ, blocked stomatal aperture areas of 154, 401, and 2,043 ㎛² were recorded at 7, 12, and 17 days after inoculation, respectively. With the recent expanded horizon of the pathosystem and its consequential impact, such studies will be useful for a proper diagnosis, identification and management of the disease on tomato worldwide.

• 식물병연구
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• 제13권3호
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• pp.191-196
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• 2007

Ampelomyces quisqualis 94013(AQ94013)는 오이 흰가루병에 대한 생물적 방제를 위하여 효과적인 기생균으로 선발되었다. AQ94013균의 대량배양기술을 개발하기 위하여 보리쌀, 쌀, 기장, 현미, 수수, 볍씨의 6종의 곡류를 이용하여 실험하였다. 그 중에서 보리쌀은 AQ94013의 생장과 포자형성에 가장 좋은 배지였다. 대량배양의 최적온도는 $25^{\circ}C$이였으며, $20^{\circ}C$와 $30^{\circ}C$ 순이었다. 암배양 보다 광을 하루에 12시간 주기로 조사한 보리쌀배지에서 포자수가 적어서 광은 AQ94013의 포자형성을 억제하였다. 그러나 $30^{\circ}C$에서 형성된 포자는 오이 흰가루병균(Sphaerotheca fusca)에 대하여 30일간 기생력을 유지하였다. 보리 AQ94013의 배양방법은 30l-발효조를 이용하여 쌀분말(40g/l)을 첨가한 보리쌀분말액체배지에서 $25^{\circ}C$에서 5일간 암배양이 포자대량배양에 매우 효과적이었다.

• Mycobiology
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• 제50권1호
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• pp.30-45
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• 2022

During a survey of plant-inhabiting fungi and water niches from Korea, noteworthy fungi were collected; among them, two new species, Paracamarosporium noviaquum sp. nov. and Phyllosticta gwangjuensis sp. nov., are described based on morphology and multi-gene phylogenies. Paracamarosporium noviaquum was characterized by its production of 1-celled and 2-celled conidia, forming conidiomata on only potato dextrose agar medium. Phyllosticta gwangjuensis was characterized by conidia hyaline, ovoid to ellipsoid shape, rounded at both ends, containing numerous guttulae or with a single large central guttule. Additional species were identified as Cosmospora lavitskiae, Monochaetia cameliae, and Roussoella doimaesalongensis, which are reported as new record species from Korea. Detailed descriptions and illustrations of these taxa are provided herein.

• Mycobiology
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• 제49권1호
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• pp.15-23
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• 2021

Two fungal strains (KNU-JJ-1827 and KNU-JJ-1829) belonging to the class Dothideomycetes were discovered from Jeju Island, Korea during this investigation of soil microfungi. Strain KNU-JJ-1827 showed fewer conidial septations, larger conidiogenous cells, and smaller conidia compared to the previously identified closest species of Didymocyrtis. Strain KNU-JJ-1829 revealed the similar characteristics of the nearest certain species of the genus Parathyridaria with the production of conidiogenous cells and conidia, because no asexual morphs were detected from the closest type strain Parathyridaria rosae. The novelty of the strains was also confirmed by analyzing molecular data using internal transcribed spacer regions and 28S rDNA. The molecular phylogeny also strongly support the detailed description and illustration for each proposed species as Didymocyrtis septata sp. nov. (KNU-JJ-1827) and Parathyridaria ellipsoidea sp. nov. (KNU-JJ-1829) isolated from soil in Korea.