Isolation and Identification of Entomopathogenic Fungi from Chili Rhizosphere Against Fall Armyworm

Background and Objective: Chili (Capsicum annuum L.) is an economically important horticultural crop that is frequently damaged by Spodoptera larvae, leading to substantial yield losses. Pest management in chili cultivation relies heavily on chemical pesticides, which pose environmental and health risks. Although entomopathogenic fungi are known to be diverse in Indonesian soils, their potential as biological control agents in chili rhizospheres remains underexplored. This study aimed to isolate and identify entomopathogenic fungi from the chili rhizosphere and to evaluate their pathogenicity against Spodoptera larvae. Materials and Methods: Soil samples were collected from the rhizosphere of chili plants and cultured to isolate fungal species. Fungal isolates were identified based on macroscopic and microscopic morphological characteristics using standard taxonomic keys. Pathogenicity assays were conducted following Koch’s postulates by inoculating Spodoptera larvae with fungal suspensions at a concentration of 10⁷ conidia/mL. Larval mortality was observed daily to assess pathogenic effects. Data were analyzed descriptively and quantitatively, with larval mortality expressed as mean percentage and evaluated using one-way ANOVA followed by Duncan’s Multiple Range Test at α = 0.05. Results: Three fungal genera, Trichoderma sp., Aspergillus sp., and Penicillium sp. were successfully isolated from the chili rhizosphere. Morphological features of the isolates were consistent with previously reported descriptions in the literature. All isolates caused mortality in Spodoptera larvae, with average death occurring on the fourth day after inoculation. Mortality was mainly associated with fungal secondary metabolites rather than visible external mycelial growth, suggesting opportunistic entomopathogenic behavior. Conclusion:The findings demonstrate that fungi inhabiting the chili rhizosphere possess pathogenic activity against Spodoptera larvae and represent promising candidates for biological control. These results support the potential use of indigenous soil fungi as environmentally friendly alternatives to chemical pesticides. Further studies focusing on metabolite characterization, field efficacy, and non-target effects are recommended to advance their application in sustainable pest management.