Chiang Mai Journal of Science

This study was conducted to identify in vitro plant growth promoting traits and antagonistic activities of endophytic fungi from Oncosperma sp. Sixty-two endophytic fungi were isolated from leaves, roots, petioles, and spines of Oncosperma sp. Ten strains [Colletotrichum sp. (1), Daldinia spp. (6), and Diaporthe spp. (3)] showed efficient plant growth-promoting traits as well as in vitro antagonistic activities. Daldinia strains MFLUCC 20-0215, MFLUCC 20-0211, and MFLUCC 20-0210 produced higher Indole-3-acetic acid (IAA) concentrations of 120.3, 96.5, and 87.5 μg/mL, respectively. Quantitative estimation of phosphate solubilization for these taxa ranged between 2.6-3.6. A dual culture technique was used to determine the in vitro antagonistic activities against pathogenic strains of Colletotrichum sp. isolated from oil palm and coffee, and Corynespora sp. from tomato. Daldinia strains MFLUCC 20-0207 and MFLUCC 20-0216 showed strong antifungal activities with 60.6-87.3% inhibition. Diaporthe strains MFLUCC 20-0206, MFLUCC 20-0208 and MFLUCC 20-0214, and Daldinia strains MFLUCC 20-0210, 20-0211, and 20-0215 exhibited moderate antifungal activity against all test pathogens. Endophytic fungi associated with Oncosperma produced positive results in plant growth activities and biocontrol potential, providing a base for further investigation. Three isolates of Daldinia (MFLUCC 20-0210, MFLUCC 20-0211, MFLUCC 20-0125) were especially promising due to their significantly high IAA production, highest phosphate solubilization, and moderate antagonistic activities. Thus, future research should focus on Daldinia as they possess great potential for a wide range of applications.