Evaluation of the influence of nitrogen sources on the growth characteristics and cultural-morphological characters of Triangularia setosa and Sordaria fimicola in culture

The study of coprophilous ascomycetes is highly relevant due to their biotechnological potential, including metabolite production, biodegradation, and roles in nutrient cycling. Aim. The introduction of Triangularia setosa and Sordaria fimicola into culture, as well as the evaluation of the effects of nitrogen sources on their growth characteristics and cultural-morphological traits. Methods. The moist chamber method was used to detect and obtain fruiting bodies of ascomycetes. Mycelial cultures were isolated from the obtained ascocarps. Colonies were cultivated on solid agar media to assess the impact of nitrogen sources on radial growth rate and morphological characteristics. Cultural and morphological features of the mycelial colonies were described according to the classification by J.A. Stalpers. Results. For the first time, it was found that morphogenesis and growth of T. setosa and S. fimicola significantly depend on the type of nitrogen source, which is manifested in the growth rate, expressed morphological, and strain-specific variability. Conclusions. The revealed sensitivity to the nitrogen regime indicates these species' potential as mo dels for studying adaptive mechanisms of metabolic regulation in coprophilous ascomycetes.