• Mycobiology
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• 제48권4호
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• pp.245-251
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• 2020

During a survey of putative fungal pathogens infecting oak trees in the Gangwon Province of the Republic of Korea, a fungus resembling a Ceratocystis sp. was repeatedly isolated from natural wounds on Quercus variabilis. Morphological comparisons and DNA sequence comparisons based on partial β-tubulin and TEF-1α gene regions showed that the fungus resided in a distinct lineage. This novel Ceratocystis species is described here as C. quercicola sp. nov. This is the first novel species of Ceratocystis to be reported from Korea. A pathogenicity test showed that it can cause lesions on inoculated trees but that it had a very low level of aggressiveness. The discovery of this fungus suggests that additional taxa residing in Ceratocystis are likely to be discovered in Korea in the future.

• The Plant Pathology Journal
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• 제37권2호
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• pp.124-136
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• 2021

Bark canker, wood discoloration, and wilting of the duku tree (Lansium domesticum) along the watershed of Komering River, South Sumatra Province, Indonesia first appeared in 2013. The incidence of tree mortality was 100% within 3 years in badly infected orchards. A Ceratocystis species was consistently isolated from the diseased tissue and identified by morphological and sequence analyses of the internal transcribed spacer (ITS) and β-tubulin regions. Pathogenicity tests were conducted and Koch's postulates were confirmed. The fungus was also pathogenic on Acacia mangium, but was less pathogenic on mango. Partial flooding was unfavourable for disease development. Two described isolates (WRC and WBC) had minor variation in morphology and DNA sequences, but the former exhibited a more pathogenic on both duku and acacia. The ITS phylogenies grouped the most pathogenic isolate (WRC) causing wilting of the duku tree within the aggressive and widely distributed ITS5 haplotype of C. fimbriata.

• Mycobiology
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• 제37권4호
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• pp.277-285
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• 2009

In this study, dual culture, poison agar, and direct methods were used to assess the ability of Trichoderma virens IMI-392430, T. pseudokoningii IMI-392431, T. harzianum IMI-392432, T. harzianum IMI-392433, and T. harzianum IMI-392434 to control Ceratocystis paradoxa, which causes the pineapple disease of sugarcane. The highest percentage inhibition of radial growth (PIRG) values were observed with T. harzianum IMI-392432 using two dual culture methods, 63.80% in Method I and 80.82% in Method II. The minimum colony overgrowth time was observed with T. harzianum IMI-392432 and the maximum was observed with T. pseudokoningii IMI-392431. Different concentrations of different day-old metabolites of Trichoderma isolates were tested against mycelial growth of C. paradoxa. The highest PIRG (84.685%) exhibited at 80% concentration of 30-day-old metabolites of T. harzianum IMI-392432 using the modified bilayer poison agar method. In the direct assay method the maximum mycelial growth weight (PIGW) was observed at the same concentration and the same day-old metabolites of T. harzianum IMI-392432. This study showed that Trichoderma isolates have a good antagonistic effect on C. paradoxa mycelial growth and T. harzianum IMI-392432 has the most potential to control the pineapple disease pathogen.

• The Plant Pathology Journal
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• 제38권2호
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• pp.131-145
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• 2022

Ceratocystis wilt disease has caused significant mortality in duku (Lansium domesticum) since 2014 and has now spread to all districts in South Sumatra, Indonesia. Recently, 16 isolates from duku representing populations from various districts in South Sumatra were isolated. Analysis for the morphological characteristic of the isolate showed that the population has a uniform morphology. Genetic analysis based on internal transcribed spacer (ITS) and β-tubulin sequences verified that the population has being dominated by the ITS5 haplotype of Ceratocystis fimbriata and a new ITS group, the ITS7b haplotype that was localized in Musi Banyuasin. Both haplotypes were highly pathogenic to duku. Inoculation tests on various forest and agroforestry plant hosts showed that both haplotypes were highly pathogenic to Acacia mangium, moderately pathogenic to Acacia carsicarpa, Eucalyptus urophylla, and Melaleuca cajuputi, but weakly pathogenic to Dyera costulata, Hevea brasiliensis, and Alstonia scholaris. Therefore, this pathogen becomes a serious threat to Indonesia's biodiversity due to its ability to infect forest and agroforestry plants, especially the indigenous ones.

• The Plant Pathology Journal
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• 제21권1호
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• pp.1-6
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• 2005

During last decade there has been noticeable progress in the research of the biology of sapstaining fungi that cause considerable economic losses to forest product industry. The researches generated broad ranges of knowledge on sapstaining fungi regarding their occurrence on conifer wood, taxonomy, nutrient physiology, pigmentation biochemistry and molecular biology, and biological control. Major problematic groups in the sapstain production are Ophiostoma, Ceratocystis, and Leptographium genera. With Ophiostoma as a model, it is found that the type of carbon source is important in the growth and pigment production of sapstaining fungi. The operation of dihydroxy naphthalene (DHN) melanin pathway for black to bluish pigment production has been confirmed in those cosmetic fungi both at biochemical and molecular levels. The development of albino technology using nutrition competition has been shown to be promising as an environmentally friendly biological control method for sapstain control.

• Journal of the Korean Wood Science and Technology
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• 제23권1호
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• pp.42-48
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• 1995

The purpose of this study is to evaluate the efficacy of metabolites produced form Streptomyces rimosus in controlling the growth of sapwood - inhabiting fungi. In order to carry out this task, the following specific fungi were tested : sapstain fungi - Ceratocystis pilifera, Ceratocystis piceae, and Aureobasidium pullulans ; mold fungi - Trichoderma hazianum, Trichoderma viride, Penicillium cirtrinum, and Aspergillus niger. Based on the tests, the following observations can be drawn. 1. The conidial germination of sapstain and mold fungi was completely inhibited leaving a clear zone around the paper disc treated with metabolites. The best inhibition was observed in A. pullulans plate and the least in T. viride. 2. Concentration of SB medium for the production of metabolites from St, rimosus affected antifungal activity of metabolites against sapwood - inhabiting fungi. Metabolites prepared from 1/3${\times}$SB medium showed the best activity and the least activity was observed in metabolites form 1/4${\times}$medium. 3. in vivo and in vitro test using wood blocks, treatment of pine sapwood blocks with metabolites also inhibited conidial germination and thus prevented discoloration. 4. Treatment with metabolites did not change the macroscopic structure of wood and did not cause the discoloration of the surface of wood by pigments produced form St. rimosus. In conclusion the results of this study indicate that antifungal metabloites of St, rimosus could be used for the biological control of sapstain and mold fungi.

• Journal of Microbiology and Biotechnology
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• 제26권3호
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• pp.488-492
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• 2016

Rhodococcus species have become increasingly important owing to their ability to degrade a wide range of toxic chemicals and produce bioactive compounds. Here, we report isolation of the Rhodococcus sp. KB6, which is a new leaf-inhabiting endophytic bacterium that suppresses black rot disease in sweet potato leaves. We determined the 7.0 Mb draft genome sequence of KB6 and have predicted 19 biosynthetic gene clusters for secondary metabolites, including heterobactins, which are a new class of siderophores. Notably, we showed the first internal colonization of host plants with Rhodococcus sp. KB6 and discuss its potential as a biocontrol agent for sustainable agriculture.

• 한국작물학회지
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• 제23권2호
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• pp.118-125
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• 1978

고구마 보유품종 및 계통들에 대한 흑반병의 저항성을 검정하여 육성모본으로 훈용하고자 병원균을 배양 접종하여 실내검정(1977연)과 고구마 묘에 접종 포장검정(1976∼'77연)을 실시한 결과 1. 실내검정 및 포장검정에서 흑반병 저항성의 품종간 차리는 현저하였으나 포장검정결과는 실내검정 결과에 비하여 연차간의 변이가 크게 나타났다. 2. 실내접종 검정에 공시한 165품종 및 계통중 수원3003, 수원3005등 15계통이 특히 강한 것으로 나타났으며 3. 포장검정에서는 161품종 및 계통중 천미, 유심 등 54계통이 강한 것으로 나타났다. 4. 실내 및 포장검정 양측에 모두 강한 품종 및 계통들은 수원59호. 수원8001. 수원90호, 농림17호, 농림2003, 70일조, 사천종3006, Hamkao, Kandee등이였다.

• 한국균학회지
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• 제45권4호
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• pp.292-303
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• 2017

2016년 버섯 재배사 내 실내공기, 식물병반(동백나무의 잎, 줄딸기, 은방울꽃, 생강나무), 버섯 배양배지 재료, 오염된 가구 등에서 진균을 분리 동정하였다. 동정된 진균 중 18종이 국내 미기록임을 확인하였다. 동정된 진균은 버섯 재배사 내 실내공기에서 6종, 식물병반에서 6종, 버섯 배양배지 재료에서 5종, 오염된 가구에서 1종이 각각 분리되었다 이들 동정된 균주에 대한 형태학적 특성과 ITS rDNA, 18S rDNA, 28S rDNA, calmodulin gene, translation elongation factor gene, ${\beta}-tubulin$ gene 등의 염기서열에 기반한 분자계통학적 관계에 대하여 기술하였다.

• Journal of the Korean Wood Science and Technology
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• 제33권2호통권130호
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• pp.65-71
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• 2005

This study was performed to understand the interaction between Ophiostomataceae and basidiomycetes fungi during cultures, and whether the basidiomycetes fungi inhibit the growth and decolorize dark pigments of blue staining fungi. The conjoint cultivation was studied on 2% malt extract agar. The ability of basidial cultures to decolorize dark pigments of ophiostomatoid fungi was the main characteristics estimated during this study. More than half of basidial cultures were characterized by deadlock interaction with blue staining fungi. In the dual cultures, where basidial partners were presented by Agaricus bisporus(64), Laetiporus sulphureus(L01/89), Trametes versicolor(09) and unknown fungus(02), antagonism was found at the phase of primary contact of colonies. Replacement interaction resulted usually in decreasing dark colour of substrate was observed for 11 basidial cultures that were belonging mainly to white-rot fungi. Among them Abortiporus biennis(123), Antrodiella hoehnelii(S28/91), Bjerkandera fumosa (137), and Gleophyllum odoratum(124) were characterized by the absence of deadlock-phase: they began to grow over dark colonies of their partners just after primary contact. Basidiomycetes did not affect strongly the pigments of Ceratocystis spp. and Leptographium sibirica isolates, but completely decolorized colonies of Ophiostoma ips and to a smaller degree Ophiostoma minus. Antrodiella hoehnelii(S28/91), Bjerkandera fumosa(137), Gleophyllum odoratum(124) and Trametes versicolor(B18/91) cultures were found to be the most active in decreasing dark color of blue staining fungi colonies. The cultures were recommended for further development as agents of biopulping of wood chips and bio-control of blue stain in woods.