Antagonistic activity of fungal symbionts associated with black truffle

Recent decades have seen increased interest in black truffles due to their gastronomic properties, high nutritional value, and potential medicinal properties. An important contribution to the specific aroma and nutritional value of these fungi is made by the community of microorganisms that inhabit truffle fruiting bodies. The present study aims to isolate pure cultures of cultivated fungal symbionts, assess their mutual antagonism, and consider their ecological role. The experiment involved collecting the fruiting bodies of the black truffle, which were used to isolate pure cultures of fungal symbionts. As a result, eight fungal strains were identified. The antagonistic properties of the obtained strains were evaluated using the agar-well method. Six of the eight strains exhibited antagonistic activity. The highest activity was exhibited by the Fusarium sp. strain LPB2023712, which inhibited the growth of six other strains with the maximum inhibition zone of ±3.3 cm. Also, significant activity was observed in the strains of Trichothecium sp. and Hypopichia sp., which inhibited the growth of Clonostachys sp. and Penicillium sp. The obtained results indicate the important role of fungal symbionts in the ecology of truffles, including their ability to regulate the microbial community and inhibit the development of pathogens in fruiting bodies. The Fusarium sp. strain LPB2023712 demonstrated potential to serve as a biocontrol agent, which opens up new opportunities to find biologically active compounds and develop methods for improving the resistance of truffles to disease. This study emphasizes the need for further research on truffles and associated microorganisms to gain a deeper understanding of their ecological functions, interactions, and practical applications in agriculture and biotechnology.

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