• Microbiology and Biotechnology Letters
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• v.30 no.4
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• pp.339-345
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• 2002

Antifungal substances were isolated from solid cultures of Fusarium equiseti FO-68 obtained from arrowhead and Fusarium sp. FO-510 obtained from egg plant, and then their antifungal activities were investigated against plant pathogenic fungi in vitro and in vivo. An antifungal substance was purifed from rice solid cultures of F. equiseti FO-68 and identified as equisetin. In addition, two antibiotic substances were isolated from solid cultures of Fusarium sp. FO-510 and their chemical structures were determined to be zearalenone and 8'-hydroxyzearalenone. in vitro, equisetin and zearalenone inhibited mycelial growth of most of the plant pathogenic fungi tested, whereas 8'-hydroxyzearalenone hardly inhibited fungal growth. In vitro, equisetin effectively controlled the development of tomato gray mold and tomato late blight. Zearalenone exhibited in vivo antifungal activity against rice blast, rice sheath blight, tomato gray mold, and tomato late blight. However, 8'-hydroxyzearale-none did not control the development of plant diseases except tomato gray mold. This is the first report on the antifungal activities of equisetin, zearalenone, and 8'-hydroxyzearalenone.