• 한국균학회지
• /
• 제47권1호
• /
• pp.19-27
• /
• 2019

우포 습지에 서식하는 식물의 근권 토양에서 수지상균근균(AMF) 포자를 추출하였다. 추출한 포자는 형태적 특성과 18S rDNA 염기서열의 분자적 분석을 이용해 동정하였다. 그 결과 6속 9종의 AMF 포자가 분리된 것을 확인하였으며, 종 다양성 지수를 계산하여 분석한 결과 습지에서 AMF 포자의 종 다양성은 식물에 의해 영향을 받는 것을 확인하였다. 연구 과정에서 국내 미기록종 1종을 확인하였으며, 확인된 종은 Diversispora epigaea이다. 미기록종 AMF 포자의 형태적 특성 및 분자적 분석의 결과에 대해 서술하였다.

• Mycobiology
• /
• 제50권4호
• /
• pp.219-230
• /
• 2022

Agaricales species form pileate-stipitate fruiting bodies and play important roles in maintaining the terrestrial ecosystem as decomposers, symbionts, and pathogens. Approximately 23,000 Agaricales species have been known worldwide, and 937 species have been recorded in the Republic of Korea. However, most of them were identified solely based on morphological characteristics that often led to misidentifications. The specimens collected from 2018 to 2020 in the Republic of Korea were identified based on phylogenetic analysis of the internal transcribed spacer (ITS) sequences. Their identities were confirmed by microscopic characteristics. As a result, 14 Agaricales species were discovered for the first time in the Republic of Korea. They belonged to nine genera: Agaricus, Calocybe, Cortinarius, Hygrocybe, Inocybe, Lepista, Leucoagaricus, Marasmius, and Psathyrella. Detailed macroscopic and microscopic descriptions were provided to help distinguish these species. The morphological and molecular data provided in this study will serve as reliable references for the identification of Agaricales species.

• 농업과학연구
• /
• 제50권4호
• /
• pp.759-771
• /
• 2023

Plant growth-promoting rhizobacteria (PGPR) are naturally occurring bacteria that intensively colonize plant roots and are crucial in promoting the crop growth. These beneficial microorganisms have garnered considerable attention as potential bio-inoculants for sustainable agriculture. PGPR directly interacts with plants by providing essential nutrients through nitrogen fixation and phosphate solubilization and accelerating the accessibility of other trace elements such as Cu, Zn, and Fe. Additionally, they produce plant growth-promoting phytohormones, such as indole acetic acids (IAA), indole butyric acids (IBA), gibberellins, and cytokinins.PGPR interacts with plants indirectly by protecting them from diseases and infections by producing antibiotics, siderophores, hydrogen cyanide, and fungal cell wall-degrading enzymes such as glucanases, chitinases, and proteases. Furthermore, PGPR protects plants against abiotic stresses such as drought and salinity by producing 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase and modulating plant stress markers. Bacteria belonging to genera such as Bacillus, Pseudomonas, Burkholderia, Pantoa, and Enterobacter exhibit multiple plant growth-promoting traits, that can enhance plant growth directly, indirectly, or through synergetic effects. This comprehensive review emphasizes how PGPR influences plant growth promotion and presents promising prospects for its application in sustainable agriculture.

• 헤리티지:역사와 과학
• /
• 제14권
• /
• pp.225-250
• /
• 1981

경남지방(慶南地方)의 지류(紙類) 및 섬유질유물(纖維質遺物) 보관고내(保管庫內) 공중균(空中菌)의 분포(分布) 조사(調査)를 위하여 중요민속자료(重要民俗資料) 37호(號) 이휴정소장출토복식(二休亭所藏出土服飾) 등(等) 4개소(個所)를 대상으로 하였다. 분리배지(分離培地)는 malt extract agar이었으며 잡균(雜菌)의 증식(增殖)을 방지(防止)하기 위(爲)하여 chloram phenicol을 첨가하여 사용하였다. 4개소 유물보관고(遺物保管庫)에서 분리(分離) 동정(同定)된 공중(空中) 사상균(絲狀菌)은 Cladosprium cladosprioides, Alternaria chlamydo-spora, Aspergillus fumigatus, A. versicolor, Eurotium chevalieri penicillum charlesii Var. rapidum, P. oxalicum, P. viridcatum, Trichoderma viride, Acremonium sp, Mucor sp, yeast 등(等) 8속(屬) 9종(種) 이었으며 또한 4개소(個所)의 유물보관고내(遺物保管庫內)에 분포(分布)된 사상균(絲狀菌) 포자(包子)는 Cladosporium cladosporioides가 제일 많았고 그 다음이 Acremonium sp, penicillium, Aspergillus Trichoderma, Aeternaria, Eurotium의 순서이었다. 또한 지류(紙類) 및 섬유질문화재(纖維質文化財)로부터 사상균(絲狀菌)을 직접 채취(直接 採取)하여 분리(分離) 동정(同定)한 결과(結果) 8속(屬) 14(種)이 검출되었다. 이중에서 가장 많이 분리(分離)된 종(種)은 Clodosporium cladosporioides이었고 그 외에 Acremonium, Penicillium, Asper gillus, Trichoderma 등도 분리(分離) 동정(同定) 되었다. 이중에서 특히 아직 우리 나라에서 미기록종(未記錄種)은 Chacetomium globosum, Mucor racemosus, Pspinalosum, Torulaellisii 등(等) 4종(種)이 발견(發見)되었음을 확인(確認)하였다. 끝으로 화학약제(化學藥劑)에 대(對)한 방균(防菌) 효과(效果) 실험(實驗)은 Aspergillus penicillium, cladosporium Trichoderma 등(等) 8종(種)을 대상으로 하였으며 약품(藥品)은 Benzoic acid, Sorbic acide, Dehydroacetic acid, Thymol 등(等) 4가지 화학약품(化學藥品)을 사용(使用)하여 방균효과(防菌效果)를 조사(調査) 하였다. 동실험결과(同實驗結果) Thymol은 0.5%이상(以上)에서 모든 균(菌)의 생장(生長)을 저지하였으며 기타 3가지의 화학약제(化學藥劑)는 각각(各各)의 농도(濃度)에 따라 억제상황(狀況)이 상이(相異)하게 나타났음을 보고(報告) 드린다.

• 미생물학회지
• /
• 제41권3호
• /
• pp.188-194
• /
• 2005

미생물학적 실내공기질을 평가하기 위하여, 울산에 위치한 중${\cdot}$고등학교 3곳이 교실과 복도에서, 학기 중(수업시간, 점심시간, 방과 후)과 방학 중 등 상황별로 공기중 미생물의 농도를 조사하였다. 미생물의 포집에는 충돌식 공기 채취기를 사용하였으며, 세균수는 plate count agar, 진균수는 dichloran rose bengal chloramphenicol agar를 사용하여 측정하였고, 이들 배지로부터 세균과 진균을 분리하여 동정하였다. 학기 중 세균 농도는 점심시간의 복도에서 평균 $1,111\;MPN/m^{3}$로 가장 높았고, 수업시간의 복도에서 평균 $132\;MPN/m^{3}$로 가장 낮았으며, 방학 중의 측정값은 교실과 복도에서 각각 학기 중 수업시간의 $5{\%}$와 $27{\%}$ 수준이었다. 조사한 집락의 $60{\%}$는 병원성과 관련이 적은 Micrococcus spp.로 동정되었고. Staphylococdcus 속은 $12{\%}$를 차지하였다. 학기 중 진균의 평균 농도는 상황별로 $105{\~}213\;MPN/m^{3}$의 범위였으며, 방학 중의 측정값은 교실과 복도에서 각각 $32\;MPN/m^{3}$와 $83\;MPN/m^{3}$이었다. 공기중 진균의 집락으로부터 Cladosporium 속, Penicillium 속, Aspergillus 속 등을 확인할 수 있었으며, 언급한 3 속이 조사한 집락의 $77{\%}$를 차지하였다. 연구의 결과는 학교 실내에서 학생수와 함께 활동성과 연관된 상황에 따른 세균 농도의 변이를 보여주었으며, 학교 환경에서 bioaerosol의 허용수준을 결정함에 있어 이를 고려해야 함을 제안하고 있다.

• 한국균학회소식:학술대회논문집
• /
• 한국균학회 2014년도 추계학술대회 및 정기총회
• /
• pp.13-13
• /
• 2014

Species belonging to the genus Fusarium are widely distributed and cause diseases in many plants. Isolation of fungal strains from air or cereals is necessary for disease forecasting, disease diagnosis, and population genetics [1]. Previously we showed that Fusarium species are resistant to toxoflavin produced by the bacterial rice pathogen Burkholderia glumae while other fungal genera are sensitive to the toxin, resulting in the development of a selective medium for Fusarium species using toxoflavin [2]. In this study, we have tried to elucidate the resistant mechanism of F. graminearum against toxoflavin and interaction between the two pathogens in nature. To test whether B. glumae affects the development of F. graminearum, the wild-type F. graminearum strains were incubated with either the bacterial strain or supernatant of the bacterial culture. Both conditions increased the conidial production five times more than when the fungus was incubated alone. While co-incubation resulted in dramatic increase of conidial production, conidia germination delayed by either the bacterial strain or supernatant. These results suggest that certain factors produced by B. glumae induce conidial production and delay conidial germination in F. graminearum. To identify genes related to toxoflavin resistance in F. graminearum, we screened the transcriptional factor mutant library previously generated in F. graminearum [3] and identified one mutant that is sensitive to toxoflavin. We analyzed transcriptomes of the wild-type strain and the mutant strain under either absence or presence of toxoflavin through RNAseq. Expression level of total genes of 13,820 was measured by reads per kilobase per million mapped reads (RPKM). Under the criteria with more than two-fold changes, 1,440 genes were upregulated and 1,267 genes were down-regulated in wild-type strain than mutant strain in response to toxoflavin treatment. A comparison of gene expression profiling between the wild type and mutant through gene ontology analysis showed that genes related to metabolic process and oxidation-reduction process were highly enriched in the mutant strain. The data analyses will focus on elucidating the resistance mechanism of F. graminearum against toxoflavin and the interaction between the two pathogens in rice. Further evolutionary history will be traced through figuring out the gene function in populations and in other filamentous fungi.

• 생명과학회지
• /
• 제22권10호
• /
• pp.1384-1391
• /
• 2012

본 연구에 사용된 해안식물은 울릉도의 해안지역으로부터 채집하였다. 그리고 식물은 큰비쑥, 해국, 갯질경이, 땅채송화, 갯강아지풀 등 5종류의 식물이 채집되었다. 울릉도에서 채집된 해안식물의 뿌리로부터 36주의 내생진균이 분리되었다. 모든 내생진균류는 ITS영역에 의해 분석 및 동정되었다. 그리고 계통분석 결과, 분리된 내생진균류는 모두 자낭균문에 속하고 4종류의 목(Capnodiales, Eurotiales, Hypocreales and Pleosporales)으로 분류되었으며, 이 중 Eurotiales 목이 가장 분포 비율이 높은 것으로 확인되었다. 그리고 내생진균류를 속으로 분류하였을 때, 9종류의 속(Alternaria, Aspergillus, Cladosporium, Exserohilum, Fusarium, Neosartorya, Penicillium, Phoma and Pyrenochaeta)으로 분류되었으며, Penicillium 속과 Aspergillus 속이 가장 우점종으로 확인되었다. 그리고 Shannon's diversity index (H')는 0.684에서 1.609의 분포로 나타났으며, 땅채송화에서 분리된 내생진균류의 다양성이 다른 식물에 비하여 높은 것으로 확인되었다.

• 식물병연구
• /
• 제24권4호
• /
• pp.308-312
• /
• 2018

2017년산 붉은곰팡이 감염 벼시료의 곰팡이 발생을 분석한 결과 Fusarium 속의 발생빈도가 가장 높았다. Fusarium 속 중에서는 Fusarium asiaticum-니발레놀 형이 79%로 우점하였다. 곰팡이독소 중에서는 제랄레논이 1117 ng/g으로 가장 많이 검출되었으며 데옥시니발레놀(163 ng/g), 15-아세틸 데옥시니발레놀(155 ng/g), 니발레놀(110 ng/g)의 순으로 높았다. 2015년산 벼시료를 붉은곰팡이 감염벼와 건전벼로 구분한 후 곰팡이독소 수준을 분석한 결과 두 시료는 모두 제랄레논으로 오염되었다. 그러나 이들 시료 간 제랄레논의 수준차이는 5배 이상이었으며 감염벼는 1400-2370 ng/g, 건전벼는 240-430 ng/g이었다. 이 결과는 벼의 제랄레논 독소 저감화를 위해 벼 수확 시 붉은곰팡이 감염종자의 제거가 필요함을 시사한다.

• 실내환경 및 냄새 학회지
• /
• 제17권4호
• /
• pp.355-361
• /
• 2018

Mold grows more easily when humidity is higher in indoor spaces, and as such is found more often on wetted areas in housing such as walls, toilets, kitchens, and poorly managed spaces. However, there have been few studies that have specifically assessed the level of mold in the indoor spaces of water-damaged housing in the Republic of Korea. We investigated the levels of airborne mold according to the characteristics of water damage types and explored the correlation between the distribution of mold genera and the characteristics of households. Samplings were performed from January 2016 to June 2018 in 97 housing units with water leakage or condensation, or a history of flooding, and in 61 general housing units in the metropolitan and Busan area, respectively. Airborne mold was collected on MEA (Malt extract agar) at flow rate of 100 L/min for 1 min. After collection, the samples were incubated at $25^{\circ}C$ for 120 hours. The cultured samples were counted and corrected using a positive hole conversion table. The samples were then analyzed by single colony culture, DNA extraction, gene amplification, and sequencing. By type of housing, concentrations of airborne mold were highest in flooded housing, followed by water-leaked or highly condensed housings, and then general housing. In more than 50% of water-damaged housing, the level of airborne mold exceeded the guideline of Korea's Ministry of Environment ($500CFU/m^3$). Of particular concern was the fact that the I/O ratio of water-damaged housing was greater than 1, which could indicate that mold damage may occur indoors. The distribution patterns of the fungal species were as follows: Penicillium spp., Cladosporium spp. (14%), Aspergillus spp. (13%) and Alternaria spp. (3%), but significant differences of their levels in indoor spaces were not found. Our findings indicate that high levels of mold damage were found in housing with water damage, and Aspergillus flavus and Penicillium brevicompactum were more dominant in housing with high water activity. Comprehensive management of flooded or water-damaged housing is necessary to reduce fungal exposure.

• 한국균학회소식:학술대회논문집
• /
• 한국균학회 2015년도 춘계학술대회 및 임시총회
• /
• pp.55-55
• /
• 2015

Rust is one of the most destructive diseases on economically important plants such as agricultural and horticultural crops, as well as forest trees [1]. Chemical treatment is the most effective means to control rust, but use of the chemical fungicides involves inevitable risks to human health and environment [2]. Unfortunately, biocontrol is currently impracticable for rust disease management [3]. It is necessary to exploit biocontrol agents to help prevent rust diseases. As a fundamental research for future development of biocontrol agents for rusts, biodiversity of hyperparasites occurring on rust fungi was investigated. During 2006-2010, 197 fungal isolates of the rust hyperparasites were collected and isolated from various combinations of mycohosts and plant hosts in many regions of Korea. Based on morphological and molecular data, they were identified as 8 genera and 12 species. Besides, phylogenetic relationships between the hyperparasites and related taxa were inferred. A total of 114 isolates of Pseudovirgaria were obtained from rust pustules of Phragmidium spp. and Pucciniastrum agrimoniae infecting rosaceous plants. Phylogenetic analysis using multigene sequences revealed a high level of genetic variability among many isolates of Pseudovirgaria and close correlation between the isolates and mycohosts. Only two species of Pseudovirgaria, P. hyperparasitica and P. grisea are often difficult to distinguish by their morphological similarity, but on the molecular basis they were clearly differentiated from each other. There had been no previous record of P. grisea outside Europe, but the present study has proved its presence in Korea. Among six distinct groups (five of P. hyperparasitica and one of P. grisea) within the Pseudovirgaria isolates, each lineage of P. hyperparasitica was closely associated with specific mycohosts and thus might have cospeciated with their mycohosts, which probably led to coevolution. Although P. grisea possesses a host preference for Phragmidium species occurring on Rubus, it was not specific for a mycohost. P. grisea seems to evolve in the direction of having a broad mycohost range. Seventeen isolates of Verticillium-like fungi were isolated from rust sori. Based on morphological data and DNA sequence analysis, the isolates were identified as three Lecanicillium species, viz. L. attenuatum, Lecanicillium sp. 1, Lecanicillium sp. 2, and V. epiphytum. The unidenified two species of Lecanicillium appear to be previously unknown taxa. Sixty-six isolates of miscellaneous hyphomycetes belonging to 6 species of 5 genera were obtained from pustules of rust fungi. On the basis of morphological and molecular analyses, the miscellaneous hyphomycetes growing on rusts were identified as Acrodontium crateriforme, Cladophialophora pucciniophila, Cladosporium cladosporioides, Phacellium vossianum, Ramularia coleosporii, and R. uredinicola.