• The Korean Journal of Mycology
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• v.32 no.1
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• pp.8-15
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• 2004

This study was conducted to discover new phytotoxins which may be used as lead molecules for the development of new herbicides. A total of 187 endophytic fungi were isolated from 11 plant species, which were collected from 8 locations in Korea. Their herbicidal activities were screened in vivo by herbicidal and duckweed bioassays after they were cultured in potato dextrose broth and rice solid media. Both fermentation broth and solid culture extract of Gliocladium catenulatum F0006 isolated from red pine (Pinus densiflora) showed 70% herbicidal activity only against cocklebur (Xanthium strumarium) out of the 10 weeds tested. Solid culture extract of F0034 isolated from arrowroot (Pueraria thunbergiana) exhibited 20 to 100% herbicidal activities against all of the weeds. Especially, shattercane (Sorghum bicolor), barnyardgrass (Echinochloa crus-galli), large crabgrass (Digitaria sanguinalis), and fall pauicum (Panicum dichtomiflorum) were sensitive to the solid culture extract of F0034. In addition, solid culture extract of F0043 isolated from red pine displayed 20% to 70% herbicidal activities only against 5 grass species, but not against 5 broad-leaf plant species. On the other hand, as the results of duckweed assay, 8 fermentation broths showed 100% growth inhibitory activity at concentrations less than 5.0% of culture supernatants and 12 solid cultures had a potent inhibitory activity against duckweed growth. A toxic metabolite was purified from the solid cultures of G. catenulatum F0006 by repeated column chromatography and bioassay. It caused a phytotoxic syndrome only on cocklebur out of the 10 weeds tested; it completely killed cocklebur seedlings at $500\;{\mu}g/ml$ and showed 85% herbicidal activity against cocklebur at $100\;{\mu}g/ml$. The molecular weight of the toxic metabolite is 238 daltons and its structure determination is underway.

• 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.