Composition of Subepidermal Mycobiota of Oilseed Rape Seeds

The article presents the results of mycological analysis of 141 samples of oilseed rape from Federal V.R. Williams Scientific Center of Forage Production and Agroecology after their surface disinfection by immersion for 1 minute in a formaldehyde solution followed by double rinsing with an ammonia solution. The subepidermal mycobiota was characterized by micromycetes of the genera Alternaria, Penicillium and Aspergillus, detected in 94,3, 44,7 and 44% of samples, respectively, with an infection rate from 1 to 100%. Alternaria fungi were mainly represented by the species A. tenuissima (in 87,9% of samples), ‘Alternaria infectoria’ (53,2%) and A. alternata (11,3%), and Aspergillus fungi were represented by A. pseudoglaucus and A. niger. Isolated cases of intensive contamination of spring rape seeds by the fungi Alternaria spp. (50…90%) and Penicillium spp. (50…100%), and winter rape seeds by Aspergillus spp. (70…90%) were established. In the winter form, the species A. pseudoglaucus was detected more often (in 48,9% of samples) than in the spring form (8,5%), A. niger was found mainly in spring rape seeds. The species Alternaria japonica, A. brassicicola, A. arborescens, Aspergillus amstelodami, A. chevalieri, A. flavus, A. versicolor, A. ochraceus were found only in isolated samples, as were representatives of the genus Fusarium (F. avenaceum, F. graminearum), Cladosporium, Stemphylium and Verticillium, found in 0,7...8,5% of samples with an infestation of no more than 4%. The mycobiota of the seeds was dominated by two species of micromycetes: Alternaria tenuissima and Aspergillus pseudoglaucus, which are known as active producers of mycotoxins.