Assessing the Various Antagonistic Mechanisms of Strains against the Brown Root Rot Pathogen Infecting Heritage Fig Trees.

A wide range of phytopathogenic fungi exist causing various plant diseases, which can lead to devastating economic, environmental, and social impacts on a global scale. One such fungus is , causing brown root rot disease in over 200 plant species of a variety of life forms mostly in the tropical and subtropical regions of the globe. The aim of this study was to discover the antagonistic abilities of two strains (#5001 and #5029) found to be closely related to against . The mycoparasitic mechanism of these strains against involved coiling around the hyphae of the pathogen and producing appressorium like structures. Furthermore, a gene expression study identified an induced expression of the biological control activity associated genes in strains during the interaction with the pathogen. In addition, volatile and diffusible antifungal compounds produced by the strains were also effective in inhibiting the growth of the pathogen. The ability to produce Indole-3-acetic acid (IAA), siderophores and the volatile compounds related to plant growth promotion were also identified as added benefits to the performance of these strains as biological control agents. Overall, these results show promise for the possibility of using the strains as potential biological control agents to protect infected trees as well as preventing new infections.