Secondary Metabolites of the Siberian Strains Heterobasidion annosum sensu lato

The composition of secondary metabolites from strains Heterobasidion genus isolated in central and western Siberia and in South Korea were studied. Morphological–cultural and molecular-genetic methods were used to assign the cultures to the species of H. annosum (Fr.) Bref. (five strains), H. abietinum Niemela & Korhonen (four strains), and H. ecrustosum Tokuda, T. Hatt. & Y.C. Give (one strain). Fomannoxin predominated in the metabolome profiles of three H. annosum strains and all H. abietinum strains. Two strains of H. annosum synthesized fomannoxin-related compounds: 2-(2-hydroxypropan-2-yl)-2,3-dihydrobenzofuran-5-carbaldehyde and 2-(2-hydroxypropan-2-yl)benzofuran-5-carbaldehyde. Fomannosin and its precursors were identified in H. annosum 45-2. It was shown that the composition of the fermentation medium affected the number and range of the synthesized metabolites. Under in vitro conditions, all H. annosum and H. abietinum strains exhibited phytopathogenic effects on Pinus sylvestris L. seedlings, causing necrotic damage to stems of various degrees and plant death. Higher phytopathogenicity is characteristic of H. annosum strains: maximal aggressiveness was observed in H. annosum 45-2 with the greatest diversity of compounds in the metabolome profile and active fomannoxin production.