Isolation and Identification of Endophytic Fungi Associated with Roots of Soybean Plant and Their Antagonist Activity against Fusarium spp.

Abstract

Soybean (Glycine max), an essential oilseed crop, is severely affected by soil-borne fungal pathogens, particularly Fusarium solani, which causes destructive diseases such as root rot and charcoal rot. The growing prevalence of these diseases, along with the negative environmental impacts associated with chemical control strategies, highlights the need for eco-friendly and sustainable disease management solutions. One promising alternative is the use of endophytic fungi as biological control agents. In the present study, healthy soybean root tissues were collected and subjected to surface sterilization followed by culturing on Potato Dextrose Agar (PDA) for endophyte isolation. Five fungal endophytes—Penicillium chrysogenum, Aspergillus niger, Aspergillus flavus, Cladosporium sp., and Curvularia sp.—were successfully isolated. Morphological and microscopic analyses confirmed their identity, and pathogenicity tests indicated that all isolates were non-pathogenic to the host plant. The antagonistic activity of these endophytes against Fusarium solani was evaluated using the dual culture technique. Among them, Penicillium chrysogenum and Aspergillus flavus showed the highest inhibition (55.56%), followed by Aspergillus niger (46.67%), Cladosporium (44.44%), and Curvularia (30.55%). Overall, the findings demonstrate the biocontrol potential of endophytic fungi associated with soybean roots, supporting their application as a sustainable approach for managing Fusarium-induced root diseases in soybean cultivation.