Work

Cornmeal-based artificial diet improves development and reduces rearing costs of Spodoptera litura

Year: 2025

Type: article

Abstract: The tobacco cutworm, Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae), is a major defoliating pest in East and South Asia and serves as an alternative host for the mass propagation of the parasitoid Telenomus remus . Therefore, optimizing the rearing cost of S. litura is critical for large-scale production to enhance efficiency and reduce costs. We evaluated 18 artificial diet formulations derived from a standard diet by incorporating corn flour and adjusting the ingredient ratios. The diets were grouped into high-, medium-, and low-cost categories, and their biological performance was assessed under controlled laboratory conditions (26 ± 1 °C, 70 ± 5% RH, and a16:8 h L:D photoperiod). Among the tested diets, formulation 15 produced the best results, yielding shorter larval (19.52 d) and pupal durations (10.46 d), higher pupal mass (500 mg), greater fecundity (2,658 eggs/female), and improved egg hatch (73.77%) compared with the control. Population parameters, including the intrinsic ( r ) and finite ( λ ) rates of increase, were significantly improved, whereas the mean generation time ( T ) and net reproductive rate ( R 0 ) decreased. Importantly, formulation 15 lowered rearing costs by 5.9% relative to the original diet. These findings demonstrate that replacing soybean flour with corn flour as the primary protein source provides a cost-effective and biologically robust diet for S. litura . This optimized diet will facilitate large-scale rearing of S. litura and mechanized production of T. remus , providing a model for reducing artificial diet costs in other insect systems.

Source: Frontiers in Insect Science

DOI: 10.3389/finsc.2025.1732857