• The Plant Pathology Journal
• /
• 제27권1호
• /
• pp.20-25
• /
• 2011

Gibberella zeae (anamorph: Fusarium graminearum), a homothallic (self-ferile) ascomycete with ubiquitous geographic distribution, causes serious diseases in several cereal crops. Ascospores (sexual spores) produced by this fungal pathogen have been suggested as the main source of primary inoculum in disease development. Here, we report the function of a gene designated GzRUM1, which is essential for ascospore formation in G. zeae. The deduced product of GzRUM1 showed significant similarities to the human retinoblastoma (tumor suppressor) binding protein 2 and a transcriptional repressor, Rum1 in the corn smut fungus (Ustilago maydis). The transcript of GzRUM1 was detected during the both vegetative and sexual stages, but was more highly accumulated during the latter stage. In addition, no GzRUM1 transcript was detected in a G. zeae strain lacking a mating-type gene (MAT1-2), a master regulator for sexual development in G. zeae. Targeted deletion of GzRUM1 caused no dramatic changes in several traits except ascospore formation. The ${\Delta}$GzRUM1 strain produced perithecia (sexual fruit bodies) but not asci nor ascospores within them. This specific defect leading to an arrest in ascospore development suggests that GzRUM1, as Rum1 in U. maydis, functions as a transcriptional regulator during sexual reproduction in G. zeae.

• 펄프종이기술
• /
• 제44권3호
• /
• pp.34-40
• /
• 2012

In this study, new antibacterial materials were developed to manufacture a functional corrugated board. Sulfur solution, a new antibacterial solution made from inorganic sulfur in the laboratory, and other antibacterial mat erials were adopted to treat the surface of a linerboard. We measured the antibacteriocidal and bacteriostatic activities, as well as the fungal resistance of the surface-treated linerboards, to identify the antibacterial properties. The mechanical properties of the surface-treated linerboard were also determined in order to identify the effects of the antibacterial materials on linerboard properties. Linerboard treated with sulfur solution, PVOH, and sodium metasulfite showed the highest antibacterial activity, while linerboard treated with sulfur solution and nano sulfur showed the highest fungal resistance. It was identified that sulfur solution has effective antibacterial properties. The antibacterial materials did not affect the mechanical properties of the surface-treated linerboard, but the binder showed significant effects in terms of the burst strength, the compressive strength, and the stiffness of the linerboard.

• 한국균학회지
• /
• 제49권1호
• /
• pp.101-108
• /
• 2021

We collected the ascomata of Tuber species from the rhizosphere of Quercus dentata in Danyang, Korea. We observed the morphological characteristics of ectomycorrhizal roots and ascomata, and identified the species based on the results of the phylogenetic analysis conducted using the DNA sequences of an internal transcribed spacer, a large-subunit rDNA, translation elongation factor 1-α DNA (TEF1), and MAT. Finally, we identified the fungal species as Tuber himalayense B.C. Zhang & Minter, which has not been recorded previously in Korea. We evaluated the morphological characteristics and conducted phylogenetic analysis of the ascoma and mycorrhiza (associated with Q. dentata) of T. himalayense.

• Mycobiology
• /
• 제46권2호
• /
• pp.92-100
• /
• 2018

The filamentous Ascomycota Colletotrichum gloeosporioides sensu lato is a fungus that has been reported worldwide as a causal agent of anthracnose disease in avocado and other crops. In Mexico, this species affects fruits from an early stage of development in the orchard until the post-harvest stage. Although fungicides are continuously applied to control Colletotrichum species, pericarp cankers and soft rot mesocarp in fruits are still frequently observed. Considering the lack of a precise description of the causative agent, the aim of the current study was to determine the pathogens involved in this symptomatology. Twenty-four isolates were consistently obtained from the pericarp of avocado fruits cv. "Hass" collected in the central avocado-producing area of Mexico. Morphological features such as colony growth, conidia size, and mycelial appressorium were assessed. Bayesian multilocus phylogenetic analyses were performed using amplified sequences of the internal transcribed spacer region of the nuclear ribosomal DNA; actin, chitin synthase, glyceraldehyde-3-phosphate dehydrogenase partial genes; and APn2-Mat1-2 intergenic spacer and mating type Mat1-2 partial gene from the nine selected isolates. In addition, fruits were inoculated with a conidial suspension and reproducible symptoms confirmed the presence of Colletotrichum fructicola in this area. This pathogenic species can now be added to those previously reported in the country, such as C. acutatum, C. boninense, C. godetiae, C. gloeosporioides, and C. karstii. Disease management programs to reduce the incidence of anthracnose should include C. fructicola to determine its response to fungicides that are routinely applied, considering that the appearance of new species is affecting the commercial quality of the fruits and shifting the original population structure.

• The Plant Pathology Journal
• /
• 제40권1호
• /
• pp.83-97
• /
• 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.

• 한국균학회지
• /
• 제26권4호통권87호
• /
• pp.450-457
• /
• 1998

Cryparin은 Cryphonectria parasitica의 세포벽에 풍부한 소수성 단백질에 속한다. cryparin은 비록 하나의 유전자에 의해 발현되지만 액체배양 후 48시간이 지나면 발현된 전체 유전자중에서 22%를 차지할 정도의 높은 발현 양상을 나타낸다. 또한 cryparin은 RNA mycovirus인 Cryphonectria hypovirus 1의 감염에 의해 발현이 현저히 억제되는 유전자로 알려졌다. 이미 지난 실험(Kim et al., 1999)에서 상동염색체간의 재조합을 이용하여 cryparin 유전자를 항생제 hygromycin B 저항성 유전자로 치환한 치환체를 제조하였다. 발현율이 매우 높으면서도 virus에 의해 밀접하게 영향받는 cryparin 유전자의 promoter 분석을 위하여서는 대상이 되는 유전자 치환을 위한 vector만을 포함하며, 분석에 이용될 여러 유전자 운반체들이 어느 한곳에만 삽입되도록 하는 성질을 가진 균주의 개발이 필요하다. 그러나 지난번 실험의 결과 얻어진 cryparin 치환체는 치환용 vector외에도 무작위로 삽입된 vector가 존재하고 나아가 새로운 vector들이 어느 한곳에만 삽입되도록 하는 성질을 갖지 못하였다. 따라서 본 실험에서는 cryparin 유전자 치환체와 영양요구성 돌연변이체인 균주간의 교잡을 이용하여 분석 대상이 되는 유전자의 치환에 이용된 vector만을 포함하며, 분석에 이용될 여러 유전자 운반체들이 genome내의 어느 한곳에만 삽입되도록 하는 성질을 가진 균주를 제조하였다.

• 식물병연구
• /
• 제26권1호
• /
• pp.48-52
• /
• 2020

2019년 7월 안동지역 노지 재배지에서 복숭아에 과실 썩음병 피해가 발생하였다. 피해 과실에서는 병이 진전됨에 따라, 썩음증상과 함께, 흰색과 자주색을 띄는 균사 및 포자가 관찰되었다. 병원균을 순수 분리한 뒤, 건전한 복숭아 과일에 접종하였을 때 동일한 과실 썩음 증상을 유도하였다. 분리된 병원균의 internal transcribed spacer (ITS), translation elongation factor 1-alpha (TEF) 그리고 β-tubulin (β-TUB) sequence 분석을 통해 Fusarium avenaceum으로 동정되었다. 따라서, 이 증상을 Fusarium avenaceum에 의한 "복숭아 과실 썩음병"으로 명명하고자 한다. 분리된 균주는 농촌진흥청 국립농업과학원 미생물 은행[Korean Agricultural Culture Collection(KACC)]에 기탁되었다(KACC accession number 48936).

• 한국응용곤충학회지
• /
• 제53권2호
• /
• pp.141-147
• /
• 2014

소나무재선충은 현재까지 도입된 국가의 토착수종인 소나무류를 모두 치사시키는 것으로 알려져 있으나, 고사목으로부터 추출 배양된 계통 중에는 소나무에 피해를 주지 않는 계통이 존재한다. 이러한 저병원성 계통 선충의 사전접종이 고병원성 소나무재선충에 대한 소나무의 저항성에 미치는 영향을 조사하기 위하여 연구가 수행되었다. 치수에 저병원성 소나무재선충을 선접종한 결과, 선접종에 의하여 소나무재선충에 대한 저항력이 유도되었다. 그 유도저항성은 1년 후까지 유지되었으며, 저병원성 선충의 반복 감염은 보다 저항성 유도 효과가 큰 것으로 나타났다. 소나무재선충에 의하여 고사한 후 경과기간이 3개월 이하인 피해목 및 피해진행목에서 분리된 선충은 모두 고병원성이었으며, 고사 후 2-3년이 경과한 벌채목에서 분리된 선충 5계통 중 4계통은 저병원성이었다. 저병원성 선충이 소나무 치수에 인공접종 되었을 때 초기 정착률은 고병원성 선충과 차이가 없었으나, 접종 30일 후에 수목내의 부위별 개체수를 조사한바 저병원성 선충의 증식률은 고병원성보다 현저히 낮았다. 저병원성 선충의 잿빛곰팡이병 균사배지에서의 선충증식 속도는 계통에 따라 차이가 있었으며, 증식속도가 빠른 계통은 대체로 고병원성 선충의 증식속도와 차이가 없었다.

• Mycobiology
• /
• 제49권4호
• /
• pp.406-420
• /
• 2021

Gloeostereum incarnatum has edible and medicinal value and was first cultivated and domesticated in China. We sequenced the G. incarnatum monokaryotic strain GiC-126 on an Illumina HiSeq X Ten system and obtained a 34.52-Mb genome assembly sequence that encoded 16,895 predicted genes. We combined the GiC-126 genome with the published genome of G. incarnatum strain CCMJ2665 to construct a genetic linkage map (GiC-126 genome) that had 10 linkage groups (LGs), and the 15 assembly sequences of CCMJ2665 were integrated into 8 LGs. We identified 1912 simple sequence repeat (SSR) loci and detected 700 genes containing 768 SSRs in the genome; 65 and 100 of them were annotated with gene ontology (GO) terms and KEGG pathways, respectively. Carbohydrate-active enzymes (CAZymes) were identified in 20 fungal genomes and annotated; among them, 144 CAZymes were annotated in the GiC-126 genome. The A mating-type locus (MAT-A) of G. incarnatum was located on scaffold885 at 38.9 cM of LG1 and was flanked by two homeodomain (HD1) genes, mip and beta-fg. Fourteen segregation distortion markers were detected in the genetic linkage map, all of which were skewed toward the parent GiC-126. They formed three segregation distortion regions (SDR1-SDR3), and 22 predictive genes were found in scaffold1920 where three segregation distortion markers were located in SDR1. In this study, we corrected and updated the genomic information of G. incarnatum. Our results will provide a theoretical basis for fine gene mapping, functional gene cloning, and genetic breeding the follow-up of G. incarnatum.