Bees & Insects

Beyond Borders, Across Generations: Hybridization Effects on Reproduction Performance, Adult Longevity and Larval Growth in Tenebrio molitor

---

Abstract

The yellow mealworm, Tenebrio molitor L. (Coleoptera: Tenebrionidae), is a promising species for large-scale rearing and has been extensively studied. Despite recent expansion in its production, optimization of rearing practices remains incomplete. Crossbreeding, a selective breeding strategy to enhance desirable traits, has only recently been applied to edible insects, and its long-term effects are still unknown. This study investigates the impact of hybridization on reproductive performance, adult longevity, and larval growth across generations, using four purebred T. molitor. strains, originating from Greece, Italy, German, and the USA. Although genetic differentiation among strains is currently under evaluation, previous phenotypic assessments have demonstrated significant differences in reproductive performance and larval growth, supporting their use as distinct parental lines for hybridization. Reproductive traits and longevity were assessed through weekly measurements of egg production, hatchability and adult survival in the F0 and F1 generations. Larval performance was evaluated in the F3 generation by measuring larval weight and survival every 14 days until the emergence of the first pupa. Results revealed that the inbred Italian strain consistently exhibited higher fertility and fecundity across generations. Two hybrid strains, i.e., German (♀) à— USA (♂) and USA (♀) à— German (♂), demonstrated heterotic effects in both fecundity and fertility, while reciprocal effects were observed in several outbred lines. Adult survival varied significantly among strains in both generations. In the F3 generation, the inbred Italian strain again outperformed all other inbred and outbred strains in larval weight and survival, followed by the German (♀) à— USA (♂) hybrid, whereas the Greek (♀) à— German (♂) hybrid displayed the shortest development time. These findings highlight the potential of crossbreeding strategies to enhance T. molitor mass rearing and to develop strains with traits suited for industrial-scale production.

Keywords: 2026

How to Cite:

Soulioti, P., Skreti, E., Rumbos, C., Mathiopoulos, K. & Athanassiou, C., (2026) “Beyond Borders, Across Generations: Hybridization Effects on Reproduction Performance, Adult Longevity and Larval Growth in Tenebrio molitor”, World Congress on Genetics Applied to Livestock Production Digital Archive 2026(1): 2294745. doi: https://doi.org/10.31274/wcgalp.24326

Rights: 1