NEMATODE-ANTAGONISTIC TRICHOTHECENES FROM Fusarium equiseti1
نویسندگان
چکیده
A strain of the fungus Fusarium equiseti isolated from soybean cyst nematode secretes nematode-antagonistic compounds. Bioassay-guided fractionation of an extract of the culture broth was undertaken to identify the compounds. Fractions were assayed for activity against a root-knot nematode (Meloidogyne incognita), a plant pathogen that attacks the roots of numerous plant species. Two trichothecene compounds were isolated that inhibited egg hatch and immobilized second-stage juveniles of this nematode: 4,15-diacetoxy12,13-epoxy-3,7-dihydroxytrichothec-9-en-8-one (4,15-diacetylnivalenol) and 4,15-diacetoxy-12,13-epoxy-trichothec-9-en-3-ol (diacetoxyscirpenol). This is the first published report of these compounds affecting plant-parasitic nematodes. Key Words—Fusarium equiseti, fungus, Meloidogyne incognita, root-knot nematode, trichothecene, nematicide, 4,15-diacetoxy-12,13-epoxy-3,7-dihydroxytrichothec-9-en-8-one, 4,15-diacetoxy-12,13-epoxytrichothec-9-en-3-ol, 4, 15-diacetylnivalenol, diacetoxyscirpenol.
منابع مشابه
Microbial Inhibition of Fusarium Pathogens and Biological Modification of Trichothecenes in Cereal Grains
Fungi of the genus Fusarium infect cereal crops during the growing season and cause head blight and other diseases. Their toxic secondary metabolites (mycotoxins) contaminate grains. Several dozen toxic compounds produced by fungal pathogens have been identified to date. Type B trichothecenes-deoxynivalenol, its acetyl derivatives and nivalenol (produced mainly by F. graminearum and F. culmorum...
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