Polyphasic taxonomy of heat-resistant paecilomyces bainier 1907 and related genera isolates from fallow agricultural soils in selected provinces of the Marmara and Ege regions

This study was conducted on 36 soil samples collected from 9 provinces located in the Marmara (Edirne, Istanbul, Sakarya, and Yalova) and Ege (Kütahya, Afyonkarahisar, Uşak, İzmir, and Muğla) regions of Türkiye, aiming to reveal the presence and biodiversity of heat-resistant Paecilomyces and related genera in agricultural soils using both conventional and molecular methods. Türkiye is a country extremely rich in soil biodiversity due to its geographical location. In this context, the presence of heat-resistant Paecilomyces and related genera in soil samples was previously detected during earlier projects, laying the groundwork for this new study. Heat-resistant Paecilomyces species are microfungi that can survive and grow even at high temperatures; therefore, they are of great importance in industrial and biotechnological applications. The fact that these species are resistant to high temperatures offers potential usage opportunities in various fields. In this study, the obtained isolates were first inoculated into selective culture media and their morphological characteristics were observed. Subsequently, multi-locus gene sequencing was performed using DNA barcode gene regions (ITS, Calmodulin, Beta-tubulin, and RPB2), and phylogenetic analyses were conducted with bioinformatics tools (MEGA 11). The results from the Marmara (5 isolates) and Aegean (10 isolates) regions revealed the presence of Paecilomyces niveus, P. divaricatus, P. fulvus, and P. brunneolus species in the soils of these regions in Türkiye. Among these, P. niveus was the most common species, detected in Afyonkarahisar, Edirne, İzmir, Kütahya, Muğla, Yalova, and Sakarya provinces. This was followed by P. divaricatus (Muğla and Uşak), P. fulvus (Uşak), and P. brunneolus (İstanbul). Notably, P. brunneolus had not been previously recorded in Türkiye soils, and this study reports it as a new record for Türkiye. This research reveals the distribution and biodiversity of heat-resistant Paecilomyces species in fallow agricultural soils in the Marmara and Ege regions of Türkiye, thereby contributing to the country's biological richness and providing valuable data for potential industrial and biotechnological applications of these microfungi.