• 식물병연구
• /
• 제27권2호
• /
• pp.70-75
• /
• 2021

The abnormal brown sunken lesions were observed on cv. RubyS apple fruits in an orchard located in Gunwi, Gyeongbuk province, Korea. The primary observed symptoms such as small round sunken lesions and small black dots on the symptomatic area were different from the reported apple diseases. The affected apple fruits were sampled and subjected to isolation of the causal agent. Cultural and morphological characteristics of isolated fungal strain, designated KNUF-20GWA4, were similar to that of Colletotrichum spp. Based on multilocus sequence analyses using internal transcribed spacer regions and partial sequences of β-tubulin, glyceraldehyde-3-phosphate dehydrogenase, chitin synthase, and actin genes, strain KNUF-20GWA4 showed 99.2-100% similarities with C. aenigma ICMP 18608 and the isolate clustered together with several other strains of this species in the phylogenetic tree. To our knowledge, this is the first report of bitter rot on apple fruits caused by C. aenigma.

• 한국균학회지
• /
• 제50권3호
• /
• pp.235-241
• /
• 2022

Anthracnose crown rot (ACR) has been observed in greenhouses during the nursery and harvest seasons in Gangwon Province, Korea. Infected plants showed black leaf spot, dark sunken pink conidial masses on petioles, wilting, and eventually death. Five isolates were obtained from the lesions of strawberry plants and were identified as a Colletotrichum gloeosporioides species complex based on their cultural and morphological characteristics. Multilocus sequence analysis of actin, calmodulin, chitin synthase, glyceraldehyde-3-phophate dehydrogenase genes, and internal transcribed spacer rDNA regions showed that the isolates formed a monophyletic group with the type strain of C. siamense. Pathogenicity tests were performed on the isolate, and Koch's postulates were performed to verify the relationship between Colletotrichum sp. and the strawberry plant variety Seolhyang. The isolate was pathogenic to strawberry plants, which exhibited typical ACR symptoms. Based on morphological characteristics, pathogenicity, and DNA sequence analyses, the fungus isolated in Korea was identified as C. siamense. This is first time C. siamense has been confirmed in ever-bearing strawberry varieties in Korea.

• 한국키틴키토산학회지
• /
• 제23권4호
• /
• pp.262-266
• /
• 2018

우리나라토종호두나무인가래나무(Juglans mandshurica Maxim.)의 수액의 유리당 함량은 약 3%로 다른 나무 수액에 비해 높게 나타났으며 미량 원소 중에는 Ca이 30 mg/kg의 농도로 포함되어 있는 것으로 확인되었다. 가래나무 수액 $200{\mu}g/ml$에서 elastase 저해 활성이 약 30% 정도를 보이고 있고 HaCaT 세포를 이용한 피부보습 효과에서는 자외선을 조사한 HaCaT세포의 aquaporin 3 유전자와 hyaluronan synthase 2 유전자 발현을 촉진시켜 hyaluronic acid의 생합성을 증가시킨 것으로 확인되었다. 본 연구를 통해 가래나무 수액의 피부 노화 방지 효능을 최초로 규명하였고 이는 가래나무 수액의 활용도를 높일 수 있는 가능성을 제시한 결과라 사료된다. 다만 물질 분석과 in-vivo 시험, 임상 연구 등 심도 있는 추가 연구가 필요할 것으로 판단된다.

• 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.

• 식물병연구
• /
• 제26권3호
• /
• pp.190-193
• /
• 2020

강원도 강릉시 사천면 비닐하우스에서 재배중인 호박 과실에 탄저병이 발생하였다. 병든 호박 과실에 분홍색의 분생포자 층이 동심원으로 나타나 점차 확대되어 과실이 무르는 증상을 나타내었다. 원인균을 규명하기 위하여 순수 분리 후 균학적 특성 및 ITS, GAPDH, CHS-1, HIS3, ACT, TUB2 염기서열 분석결과 Colletotrichum fioriniae로 동정하였다. 또한, 병원성이 확인되었고 접종시험에서 동일한 균이 반복적으로 분리되었다. 따라서, 이러한 결과를 바탕으로 C. fioriniae에 의한 호박 과실에 발생하는 탄저병의 발생을 국내 처음으로 보고한다.

• Journal of Ginseng Research
• /
• 제44권1호
• /
• pp.161-167
• /
• 2020

Background: The ascomycete fungi Cylindrocarpon destructans (Cd) and Fusarium solani (Fs) cause ginseng root rot and significantly reduce the quality and yield of ginseng. Cd produces the secondary metabolite radicicol, which targets the molecular chaperone Hsp90. Fs is resistant to radicicol, whereas other fungal genera associated with ginseng disease are sensitive to it. Radicicol resistance mechanisms have not yet been elucidated. Methods: Transcriptome analyses of Fs and Cd mycelia treated with or without radicicol were conducted using RNA-seq. All of the differentially expressed genes (DEGs) were functionally annotated using the Fusarium graminearum transcript database. In addition, deletions of two transporter genes identified by RNA-seq were created to confirm their contributions to radicicol resistance. Results: Treatment with radicicol resulted in upregulation of chitin synthase and cell wall integrity genes in Fs and upregulation of nicotinamide adenine dinucleotide dehydrogenase and sugar transporter genes in Cd. Genes encoding an ATP-binding cassette transporter, an aflatoxin efflux pump, ammonium permease 1 (mep1), and nitrilase were differentially expressed in both Fs and Cd. Among these four genes, only the ABC transporter was upregulated in both Fs and Cd. The aflatoxin efflux pump and mep1 were upregulated in Cd, but downregulated in Fs, whereas nitrilase was downregulated in both Fs and Cd. Conclusion: The transcriptome analyses suggested radicicol resistance pathways, and deletions of the transporter genes indicated that they contribute to radicicol resistance.

• 한국환경농학회지
• /
• 제37권4호
• /
• pp.324-332
• /
• 2018

곤충은 변온동물로 육지생태계에서 주로 서식하면서, 식물의 생체량 조절, 종다양성 유지에 중요한 역할을 한다. 주변온도는 변온동물인 곤충의 생리적 반응속도, 뿐만 아니라 생존과 분포를 결정하며, 기후변화에 영향을 준다. 본 연구는 높은 온도에서 곤충의 적응성에 관련있는 유전자를 전사체를 이용하여 동정하였다. 고온에서 사육된 배추좀나방 유충의 지방체로부터 차세대 염기서열 분석법을 이용하여 전사체를 확보하였다. 대사중심인 지방체에서 구조단백질, 열충격단백질, 항산화단백질, 해독효소 들이 동정되었다. 이들 중에서 표피단백질(표피단백질, 키틴합성효소, 엑틴, 카이틴 합성), 스트레스관련단백질(시토크롬 P450), 열충격단백질, 한산화단백질은 발현이 증가되었으나, glutathione S transferase 발현은 오히려 감소되었다. 이상의 결과는 기후변화의 주요인인 온난화에 대한 해충의 생리적 대응과 온도적응을 이해하는데 필요한 기초자료를 제시한다.

• The Plant Pathology Journal
• /
• 제39권4호
• /
• pp.384-396
• /
• 2023

Colletotrichum acutatum species complex is one of the most important groups in the genus Colletotrichum with a high species diversity and a wide range of host plants. C. acutatum and related species have been collected from different plants and locations in Korea and deposited into the Korean Agricultural Culture Collection (KACC), National Institute of Agricultural Sciences since the 1990s. These fungal isolates were previously identified based mainly on morphological characteristics, and a limitation of molecular data was provided. To confirm the identification of species, 64 C. acutatum species complex isolates in KACC were used in this study for DNA sequence analyses of six loci: nuclear ribosomal internal transcribed spacers (ITS), betatubulin 2 (TUB2), histone-3 (HIS3), glyceraldehyde3-phosphate dehydrogenase (GAPDH), chitin synthase 1 (CHS-1), and actin (ACT). The molecular analysis revealed that they were identified in six different species of C. fioriniae (24 isolates), C. nymphaeae (21 isolates), C. scovillei (12 isolates), C. chrysanthemi (three isolates), C. lupini (two isolates), and C. godetiae (one isolate), and a novel species candidate. We compared the hosts of KACC isolates with "The List of Plant Diseases in Korea", previous reports in Korea and global reports and found that 23 combinations between hosts and pathogens could be newly reported in Korea after pathogenicity tests, and 12 of these have not been recorded in the world.

• 한국균학회지
• /
• 제52권1호
• /
• pp.55-60
• /
• 2024

2023년 8월 청주 땅콩 재배포장에서 기보고되어 있는 점무늬 병징과는 다른 양상의 잎 반점을 발견하였다. 갈색 반점은 주로 잎 가장자리에 형성되었으며, 반점 부위에서 원인균을 분리하였다. 순수 분리한 병원균을 땅콩 유묘에 인공접종하여 병원성 검정을 수행하였다. 그 결과, 접종 5-7일 뒤에 유사한 병징을 확인할 수 있었고 병징 부위에서 동일한 균을 재분리하였다. 분리한 균주의ACT-CHS-1-GAPDH-ITS-TUB2 영역을 이용하여 동정 및 유연관계 분석을 수행한 결과 C. sojae임을 확인하였다. 따라서 본 연구는 국내 최초로C. sojae에 의해 발생한 땅콩 탄저병을 보고하고자 한다.

• 한국응용곤충학회지
• /
• 제57권3호
• /
• pp.165-175
• /
• 2018

곤충은 넓은 범위의 온도영역에 사는 것으로 알려져 있으나, $40^{\circ}C$가 넘는 고온이나 빙결온도 이하의 저온에서는 생존이 어렵다. 본 연구는 사육온도 조건이 다른 환경에서 대사중심 조직인 지방체의 유전자 발현을 분석하기 위해, 온도조건을 달리하여 담배나방을 저온 사육충 ($3{\sim}10^{\circ}C$), 고온 사육충 ($35^{\circ}C$)로 나누고 상온 사육충 ($25^{\circ}C$)을 대조구로 사용하여 전사체 분석을 수행하였다. 저온에서 특이적으로 높은 발현을 보인 유전자는 표피단백질, ${\Delta}9$ 불포화효소, 글리세롤 3-인산 탈수소효소이며, 저온에서 발현이 낮아진 유전자는 키틴 합성효소, catalase, UDP-당전이 효소이다. 고온에서 특이적으로 높은 발현을 보인 유전자는 과산화물제거효소, metallothionein 2, phosphenolpyruvate carboxykinase, 트레할로스 운반단백질이었다. 고온에서 높고 저온에서 낮은 대조적 발현을 보인 유전자는 열충격단백질, glutathione peroxidase이었다. 이들 온도 특이적이거나 대조적 발현을 보이는 유전자는 기후변화에 관련한 특이마커로 활용이 가능할 것으로 사료된다.