Secondary metabolites of Siberian phytopathogenic fungi of the genus Corinectria Gonzalez & Chaverri and their phytotoxicity

Ascomycete fungi isolated in Central Siberia from canker lesions of Abies sibirica Ledeb. were assigned to the genus Corinectria Gonzalez & Chaverri. Our earlier research has shown four Corinectria Siberian strains to be significantly different genetically from the known Corinectria spp. This work investigated the secondary metabolites of 23 morphologically similar Corinectria Siberian strains and their phytotoxicity. The strains were divided into two types by their morphological and cultural traits, MCT1 and MCT2. The MCT1 strains synthesized the meroterpenoids ilicicolins A and B, ilicicolin A epoxide and chlorocylindrocarpol; the MCT2 strains produced ilicicolins C, D (ascochlorin), F and ascofuranol. The phytotoxicity of the Corinectria strains showed a significant heterogeneity to Picea obovata seeds and was exhibited by 31% of the MCT1 strains and 50% of the МСТ2 strains. The more phytotoxic strains had an inhibitory effect on A. sibirica calluses. Ilicicolins C, D, and F synthesized by the MCT2 strains significantly inhibited the growth processes of both A. sibirica seedlings and Pinus sibirica Du Tour saplings.