Comparative proteome analysis of Spodoptera litura-infested Zea mays reveals a robust defense strategy targeting insect peritrophic membrane.

ABSTRACT

Herbivorous insects such as Spodoptera litura, pose a constant threat to agricultural crops. The incompetence of contemporary pest management tools and techniques stipulates unravelling of molecular dogma, that drives pest-plant interaction. From our previous observations, we inferred that despite being a voracious polyphagous herbivore, S. litura growth and adaptability is severely hampered on maize foliage diet. In this investigation we explored further and demonstrated the impact of maize diet on the insect gut peritrophic membrane (PM, a crucial membrane involved in compartmentalizing digestive events and absorption of nutrients), its structural analysis using scanning electron microscopy (SEM) revealed damaged and perforated PM. Further, this study delves into the intricate resistance mechanism adapted by Z. mays against S. litura by conducting a comparative proteome analysis. We have detected 345 differentially abundant proteins (DAPs) at p < 0.05 and fold change ≥1. The DAPs were categorized as plant defense, secondary metabolite synthesis, redox homeostasis, cytoskeleton/cell wall biosynthesis, primary metabolism, transport and molecular processes. We remarkably report differential expression of proteolysis- and defense-related proteins that have potential to target insect gut, digestion and absorption of nutrients. Our findings contribute to a deeper understanding of the molecular dynamics governing maize resistance against S. litura. Understanding of such intricate molecular dialogues at these interfaces could provide valuable information on the arms race between plants and herbivores, it may pave the way for innovative pest management strategies.