Seasonal dynamics and enzyme profiles of diverse endophytic fungi in Sterculia urens Roxb.: insights into host-associated trends.

Sterculia urens Roxb., well known for its medicinal uses, remains largely unexplored in terms of its fungal endophytic communities. This study is the first comprehensive assessment of fungal endophyte diversity in S. urens. Sampling was conducted across different plant parts, seasons, and study sites. Molecular identification of fungal isolates was carried out using ITS sequencing. Additionally, colonization frequency and endophytic fungal diversity were analyzed. These isolates were evaluated for extracellular enzyme. A total of 31 different endophytic fungal species, representing 16 genera, were identified based on > 97% ITS sequence similarity. Colonization frequency was significantly influenced by season (P ≤ 0.0001), tissue type (P ≤ 0.0001), and site (P ≤ 0.0001). Diversity indices revealed a significant difference in relation to season and tissue type, but not with respect to location. Furthermore, this study reports, for the first time globally, the identification of Chaetomium meridiolense and Crinipellis wandoensis as endophytic fungi. Extracellular enzyme analysis revealed enzymatic activity in 29 morphotypes. The diverse enzymatic profiles of these fungal endophytes highlight their potential for various biotechnological applications. In addition, molecular and genomic investigations will provide a deeper understanding of the functional roles and symbiotic mechanisms of these fungal endophytes. Potential applications of this research include enhancing plant growth and stress tolerance, developing sustainable biofertilizers and biocontrol agents, promoting eco-friendly bioremediation strategies for dye-contaminated environments, and discovering novel enzymes suitable for industrial biotechnological processes.