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The endogenous pool of phytoregulators in plant tissues supplied with microbial secondary metabolites may be crucial for the development of winter wheat seedlings during cool springs. The phytohormones may be synthesized by psychrotrophic microorganisms in lower temperatures occurring in a temperate climate. Two fungal isolates from the Spitzbergen soils after the microscopic observations and “the internal transcribed spacer” (ITS) region molecular characterization were identified as Mortierella antarctica (MA DEM7) and Mortierella verticillata (MV DEM32). In order to study the synthesis of indoleacetic acid (IAA) and gibberellic acid (GA), Mortierella strains were grown on media supplemented with precursor of phytohormones tryptophan at 9, 15 °C, and 20 °C for nine days. The highest amount of IAA synthesis was identified in MV DEM32 nine-day-culture at 15 °C with 1.5 mM of tryptophan. At the same temperature (15 °C), the significant promoting effect (about 40% root and shoot fresh weight) of this strain on seedlings was observed. However, only MA DEM-7 had the ACC (1-aminocyclopropane-1-carboxylate) deaminase activity with the highest efficiency at 9 °C and synthesized IAA without tryptophan. Moreover, at the same conditions, the strain was confirmed to possess the strong promoting effect (about 40% root and 24% shoot fresh weight) on seedlings. Both strains synthesized GA in all tested terms and temperatures. The studied Mortierella strains had some important traits that led them to be considered as microbial biofertilizers components, improving plant growth in difficult temperate climates.

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The abilities and keratinolytic activity of saprotrophic microfungi (37 strains) have been investigated. Uniform criteria for the evaluation of this activity have been established.

The frequency and species diversity of keratinophilic fungi in 38 nests of nine species of wetland birds were examined. Nine species of geophilic dermatophytes and 13 <em>Chrysosporium</em> species were recorded. <em>Ch. keratinophilum</em>, which together with its teleomorph (<em>Aphanoascus fulvescens</em>) represented 53% of the keratinolytic mycobiota of the nests, was the most frequently observed species. <em>Chrysosporium tropicum, Trichophyton terrestre</em> and <em>Microsporum gypseum</em> populations were less widespread. The distribution of individual populations was not uniform and depended on physical and chemical properties of the nests (humidity, pH).