Biological characteristics of Fusarium isolates, received from Triticum aestivum L. grains, during cultivation in different media

The main goal was to extract the isolates of the Fusarium genus from the grain of Triticum aestivum L. and to explore some particular biological characteristics under conditions of cultivation on various nutrient media with different chemical composition. Methods. In this paper, the cultural and morphologic features of received isolates of mycelial fungi were defined in order to explore how different components of cultivation media affect mycelial characteristics and growth. For the detailed description of isolates, the speed of the radial growth of mycelium in different media was also determined. Results. Based on discovered cultural and morphological features, extracted from the grain of Triticum aestivum L. Isolates were classified as Fusarium genus. It was determined that the chemical composition of nutrient media significantly influences the cultural characteristics and the rate of linear growth of isolates. A semi-synthetic medium, Potato-Dextrose Agar, was the most favorable for active colonies formation and pigment production of studied isolates. The rate of linear growth was the highest for all explored isolates during cultivation in this medium. During cultivation in synthetic media, the cultural characteristics and growth were more stable, although the growth rate and colonies formation were slowed down: less pigment production was also observed. High levels of carbohydrates in nutrient media promote active and rapid growth of colonies, nevertheless it excess led to the lysis of some studied Fusarium strains. It was also found out that different source of nitrogen in media did not affect cultural characteristics and the growth rate. Conclusions. The linear growth rate is substantially dependent on the composition of the media and characterizes the individual nutritional needs of the Fusarium sp. The studied biological features of isolates expanded the spectrum of characteristics, which allows to prognose a strategy of their behavior in agrocenoses in the future.