• Mycobiology
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• v.31 no.2
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• pp.74-80
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• 2003

Isolates of Trichoderma spp. collected from Pleurotus ostreatus and P. eryngii beds, which included loosened substrate compactness and development of green colour, were grouped into three species. The occurrence of different species of Trichoderma was as T. cf. virens(70.8%), T. longibrachiatum(16.7%) and T. harzianum(12.5%). The conidia of Trichoderma spp. were ellipsoidal, obovoid and phialides were bowling pins, lageniform and the length of phialides was $3.5{\sim}10.0{\times}1.3{\sim}3.3{\mu}m$. Phialides of T. cf. virens and T. harzianum were tending clustered, but it was solitary disposition in T. longibrachiatum. T. cf. virens was characterized by predominantly effuse conidiation, sparingly branched, and fertile to the apex and it was penicillate type. RAPD analysis could detect variability amongst three different species of Trichoderma using two newly designed URP-primers. However, intra-specific variation could not be detected in all the isolates except for rDNA sequence data classified Trichoderma isolates into three distinct groups representing three species. The profiles of rDNA sequences of isolates representing a species showed high similarity in T. cf. virens and T. harzianum. However, there was a variation in rDNA sequences of isolates representing T. longibrachiatum. The results of present study reveals that molecular techniques of RAPD and rDNA sequencing can greatly aid in classification based on morphology and precise identification of fast evolving species of Trichoderma.

• The Korean Journal of Mycology
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• v.21 no.4
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• pp.323-331
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• 1993

The protoplast formation and intergeneric protoplast fusion between Gliocladium virens and Trichoderma harzianum were attempted to obtain fusants. Protoplast formation was the most effective when the strains were treated with concentration of 5 mg/ml of Novozyme 234 and Cellulase at $25^{\circ}C$ for 3 hours in phosphate buffer, pH 6.5, supplemented with 0.6 M sorbitol as osmotic stabilizer. Auxotrophic mutants of G. virens G88 did not grow in minimal medium and benomyl resistant T. harzianum T95 from wild types, however, was selected by treatment with UV light as genetic marker to isolate fusants. When the intergeneric protoplast fusion between G. virens G88 and T. harzianum T95 was carried out using 30% PEG 4000 containing 10 mM $CaCl_{2}$, and 50 mM glycine (pH 8.5) as fusogenic agent at $25^{\circ}C$ for 10-15 min, the fusion frequency was $0.8{\times}10^{-4}$. Fusants obtained from intergeneric protoplast fusion were spontaneously segregated into va rious strains by continous culture on complete medium. Several intergeneric hybrids were classified into three types: parent-like hybrids, segregants, and recombinants.

• The Plant Pathology Journal
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• v.20 no.4
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• pp.271-276
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• 2004

To examine the control effect of damping-off on radish caused by Pythium spp., researchers used the isolates of a fungivorous nematode, Aphelenchus avenae, and antagonistic fungi, Trichoderma spp. These were used as biocontrol agents, either alone, or in combination. Growth rates of the A. avenae isolates and fungal damages by the nematodes varied depending on Trichoderma spp., which contained lower T. koningii and T. virens cultures than other Trichoderma cultures. Phythium spp. were damaged by all five Aphelenchus isolates, but the multiplication rate of nematode isolate Aa-3 was very poor. Antibiotic activity of T. virens and T. harzianum to Pythium spp. was stronger than that of T. koningii. Control efficacy against damping-off of radish was most enhanced under the treatment using the nematode-T. harzianum combination. On the contrary, the combinations of the nematodes and T. virens or T. koningii mostly did not increase or decreased their control effect vis-$\`{a}$-vis that of the nematodes or antagonistic fungi being used alone. The results suggest that the fungivorous nematodes may play a leading role in the disease control, and that the activity of the fungivorous nematodes may be activated by T. harzianum, but inhibited by T. koningii and T.virens.

• Journal of Microbiology and Biotechnology
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• v.7 no.3
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• pp.161-166
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• 1997

Nuclei were isolated from the protoplasts of Trichoderma harzianum T95 and treated with colchicine, a polyploid inducer. The nuclei were transferred into the protoplast of multi-auxotrophic Gliocladium virens G88 which cannot grow in minimal medium. The protoplast of G. virens G88 carrying the transferred nuclei were regenerated in a regeneration minimal medium containing $17{\mu}g/ml$ of chloroneb as a haploid inducer. Six intergeneric hybrids between G. virens and T. harzianum were isolated from the regeneration minimal medium. The hybrids could be classified into three types according to morphology, those with an isozyme pattern, those with an protein band and those with an randomly amplified polymorphic DNA(RAPD) pattern produced by random primers and repetitive sequences. The first group was identified to be a haploid recombinant, the second group a heterokaryon, and the third appeared to be petite.

• Mycobiology
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• v.31 no.3
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• pp.139-144
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• 2003

This study was conducted to investigate physiological characteristics of Trichoderma spp. isolated from Pleurotus spp. Damage tests of Pleurotus spp. and mycotoxins tests of Trichoderma spp. were also done. The optimal growth temperature of Trichoderma spp. was $27{\sim}30^{\circ}C$. Although, T. longibrachiatum was able to grow at $37^{\circ}C$ and grew $30{\sim}40$ times faster than Pleurotus. The colony colour on PDA medium of T. cf. virens was yellowish green, T. longibrachiatum was yellow, and T. harzianum was turning to bright green. In damage tests of Pleurotus by Trichoderma, T. cf. virens caused the most severe damage to Pleurotus. T. longibrachiatum and T. harzianum caused less damage on Pleurotus but were able to cause greater damage to P. eryngii. One of the mushroom cultivars, P. ostreatus 8 was the most resistant to all Trichoderma spp.. Chitinolytic mycotoxin released by Trichoderma spp. caused 52.7% damage to Pleurotus. Mycotoxins released by T. longibrachiatum caused the greatest damaged(78.6%) on P. eryngii.

• Journal of Mushroom
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• v.12 no.2
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• pp.132-137
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• 2014

Green mold disease caused by Trichoderma species has recently caused considerable damage to oyster mushroom industries in Korea. This disease Trichoderma, Penicillium, Aspergillus, such as in (genus) to be included in a disease caused by a species that collectively the largest incidence and damage is caused by the pathogen Trichoderma genus. T. longibrachiatum, Trichoderma koningii, Trichoderma virens, T. hazianum, T. atroviride, and T. pseudokoningii were detected on oyster mushroom beds and, of them, T. virens, T. hazianum, T. longibrachiatum was the most frequently detected. The knowledge concerning physiological and ecological properties of Trichoderma spp. was essential for their effective control. T. longibrachiatum hyphal growth is very fast, spore formation, and, particularly well-chlamydospore formation characteristics, and reviews are dark green discoloration. T. koningii, fast mycelial growth, aerial hyphae and spores in aerial hyphae formation is concentrated. T. virens, especially if the color change caused by spore-forming, slow, late in infection, the more severe the damage is discovered. T. hazianum fast mycelial growth, white aerial hyphae and late turns dark green. After spore formation hyphae glob of white pustules or tufts on the top of the formation. T. atroviride. aerial hyphae usually the mycelial growth and spore formation in the unlikely event of the formation and smells similar to the smell of coconut is that. Fast T. pseudokoningii mycelial growth, spore formation is formed around the inoculation site, discoloration of the medium color and well formed chlamydospores.

• The Korean Journal of Mycology
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• v.22 no.3
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• pp.276-280
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• 1994

To obtain hybrids producing antagonisms and plant growth promoting effects by intergeneric nuclei transfer, the nuclei were isolated from the protoplasts of Trichoderma harzianum T95 and treated with colchicine. The nuclei were tranferred into protoplast of multi-auxotrophic Gliocladium virens G88 which cannot grow in minimal medium. The nuclei tranferred into protoplasts of G. virens G88 were selected on the regeneration minimal medium containing chloroneb as a haploid inducer. Low transfer frequency of 0.08% was observed with three chemical treatment, however no segregants were found in the intergeneric nuclei transfer. The various types of hybrids with different morphology were detected when different concentration of chloroneb were treated. These morphologies were classified as parental, recombinant and petite type.

• The Plant Pathology Journal
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• v.21 no.3
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• pp.221-228
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• 2005

A total of 179 isolates of Trichoderma spp. were collected from oyster mushroom substrates in Korea. On the basis of morphological and cultural characteristics, Trichoderma isolates were divided into seven groups, namely T. atroviride, T. citrinoviride, T. harzianum, T. longibrachiatum, T. virens, and two unidentified species, referred to as Trichoderma sp. 1 and 2. The predominant species was Trichoderma sp. 2 (n=86) followed by Trichoderma sp. 1 (n=52). Trichoderma sp. 1 and 2 were morphologically distinct not only from the other species of Trichoderma reported but also from each other in the characteristics such as mycelial growth rate, colony appearance, shape of conidia and conidiophores and branching pattern of phialides, although branching pattern of phialides of Trichoderma sp. 1 was similar to that of T. harzianum. In virulence test, the degree for compost colonization of Trichoderma sp. 2 was significantly greater than that of the other Trichoderma species. Trichoderma sp. 2 was found to be the main cause of green mold disease in oyster mushroom production. More work including molecular characterization is needed to confirm the species of Trichoderma sp. 1 and 2.

• Journal of Microbiology and Biotechnology
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• v.21 no.1
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• pp.5-13
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• 2011

In this study, seven Trichoderma species (33 strains) were classified using secondary metabolite profile-based chemotaxonomy. Secondary metabolites were analyzed by liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS-MS) and multivariate statistical methods. T. longibrachiatum and T. virens were independently clustered based on both internal transcribed spacer (ITS) sequence and secondary metabolite analyses. T. harzianum formed three subclusters in the ITS-based phylogenetic tree and two subclusters in the metabolitebased dendrogram. In contrast, T. koningii and T. atroviride strains were mixed in one cluster in the phylogenetic tree, whereas T. koningii was grouped in a different subcluster from T. atroviride and T. hamatum in the chemotaxonomic tree. Partial least-squares discriminant analysis (PLS-DA) was applied to determine which metabolites were responsible for the clustering patterns observed for the different Trichoderma strains. The metabolites were hetelidic acid, sorbicillinol, trichodermanone C, giocladic acid, bisorbicillinol, and three unidentified compounds in the comparison of T. virens and T. longibrachiatum; harzianic acid, demethylharzianic acid, homoharzianic acid, and three unidentified compounds in T. harzianum I and II; and koninginin B, E, and D, and six unidentified compounds in T. koningii and T. atroviride. The results of this study demonstrate that secondary metabolite profiling-based chemotaxonomy has distinct advantages relative to ITS-based classification, since it identified new Trichoderma clusters that were not found using the latter approach.

• The Korean Journal of Mycology
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• v.27 no.3 s.90
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• pp.191-197
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• 1999

The phylogenetic position of Gliocladium and its related taxa were investigated, using the neighbor-joining method of the sequences from internal transcribed spacers (ITS1 and ITS2) and 5.8S ribosomal DNA (rDNA). It was focused especially on the generic concept by comparing with the related genera such as Trichoderma, Hypocrea, Verticillium, Penicillium and Talaromyces. Gliocladium species and its related genus were divided into three groups by the phylogenetic analysis using the neighbor-joining method. The first group includes Penicillium-like strains such as Penicillium, Tararomyces, Verticillium and one species of Gliocladium (G. cibotii JCM 9203 and JCM 9206). Especially, Gliocladium cibotii JCM 9203 is thought to be the similar species with Verticillium bulbillosum JCM 9214. Between these two species, Gliocladium cibotii and Verticillium bulbillosum, the intraspecies concept needs to examined with culture condition. and morphological properties. The second group includes two species Verticillium, Verticillium tricorpus and Verticillium albo-atrum which extracted from the GenBank database in NCBI (National Center for Biotechnology Information). Trichoderma-like strains, such as Trichoderma, Hypocrea and several species of Gliocladium are included in the third group. Also, Gliocladium penicillioides IFO 5869 and Gliocladium catenulatum ATCC 10523 formed the subgroup of Trichoderma-like strains. The species of Gliocladium were dispersed in Trichoderma-like and Penicillinum-like group, and only one species of Gliocladium cihotii used in our study was located in Penicillium-like genus group. The species of Verticillium appeared in all three groups and the species of Trichoderma formed the monophylogeny with Hypocrea (telemorph). Also, Gliocladium virens was grouped with Trichoderma harzianum with a high bootstrap value, supporting that Gliocladium virens is to be placed in Trichoderma. The results suggest that Gliocladium is polyphyletic, and is more Trichoderma-like than Penicillium-like.