Entomopathogenic, antifeedant, and repellent activities of indigenous Trichoderma sp. LB1 for managing common cutworm, Spodoptera litura (Fabricius)

Spodoptera litura (Fabricius), commonly known as the common cutworm, is a polyphagous pest that poses a significant threat to global agriculture. The widespread use of synthetic insecticides has led to the development of resistance in S. litura populations, necessitating the exploration of sustainable pest management strategies. This study investigated the biocontrol potential of an indigenous Trichoderma sp. strain LB1, isolated from the cadaver of a fifth instar S. litura larva in broccoli fields in West Java, Indonesia. Laboratory experiments, including conidial susceptibility assays, antifeedant assays, and dual-choice behavioral assays, were conducted to assess the biocontrol efficacy of Trichoderma sp. LB1. Results demonstrated significant larval mortality rates of up to 94.29 % following conidial infection. Furthermore, the antifeedant activity test revealed a 62 % reduction in leaf consumption by S. litura larvae, while the repellent activity test indicated a strong preference for avoiding cabbage leaves treated with Trichoderma sp. LB1 conidia, with a preference index of 58 %. These findings strongly suggest that Trichoderma sp. LB1 holds considerable promise as a sustainable and effective biocontrol agent for managing S. litura populations in agricultural systems. • Spodoptera litura poses a major threat to global agriculture as a polyphagous pest. • Synthetic insecticide overuse has driven resistance in S. litura populations. • Trichoderma sp. LB1 exhibited larval mortality rates up to 94.29 %. • Antifeedant activity reduced leaf consumption by S. litura by 62 %. • LB1-treated leaves showed good repellence with a preference index of 58 %.