The greater wax moth, Galleria mellonella, is a significant pest in apiculture and a well-established model organism for immunological and ecotoxicological studies. This investigation explores the individual and combined effects of the ectoparasite Bracon hebetor (B.h.) and the entomopathogenic nematode Steinernema carpocapsae (S.c.) on G. mellonella larvae. We evaluated the activity of oxidative stress enzymes, including superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione S-transferase (GST), malondialdehyde (MDA) levels, cytochrome P450 activity, cell viability using Annexin V-FITC, DNA damage via comet assay, and larval morphology through scanning electron microscopy (SEM). Control larvae exhibited higher GPx and GST activities compared to those treated with B.h., S.c., or the B.h. + S.c. combination. Conversely, MDA levels displayed the opposite trend. SOD activity was reduced in the B.h. and S.c. groups but significantly higher in the combined treatment. Cytochrome P450 activity increased in response to parasitism by B. hebetor. The Annexin V-FITC assay revealed decreased cell viability in parasitized groups (B.h. 79.4%, S.c. 77.3%, B.h. + S.c. 70.1%) compared to controls. DNA damage analysis demonstrated significant differences between groups, and SEM observations confirmed severe cuticle abnormalities or malformations in G. mellonella larvae. These findings highlight the complex interactions between B. hebetor, S. carpocapsae, and their host, G. mellonella. Additionally, they illuminate the intricate physiological responses triggered within the host larvae.

RNA interference (RNAi) is a sequence-guided approach to insect pest management, but its efficacy depends on more than the choice of an essential target gene. The biological activity of exogenously applied double-stranded RNA (dsRNA) is shaped by its molecular properties, extracellular stability, interactions with delivery materials, cellular uptake, intracellular trafficking, and access to the RNAi machinery. This review examines these linked determinants and considers how differences in insect physiology contribute to variation in RNAi susceptibility. We discuss target-gene selection and sequence specificity alongside nuclease activity, gut barriers, endosomal processing, and systemic transport. Particular attention is given to nanomaterial-based formulations, including chitosan, liposomes, and layered double hydroxides, as well as microbial, symbiont-mediated, host-induced gene silencing (HIGS), and spray-induced gene silencing (SIGS) platforms. Their potential benefits are assessed in relation to formulation reproducibility, production costs, environmental fate, non-target exposure, and regulatory requirements. By connecting dsRNA structure–function relationships with delivery biology and application performance, this review identifies mechanistic questions and validation steps that must be addressed to develop reliable RNAi-based tools. RNAi is best regarded as a complementary component of integrated pest management, with field deployment requiring species-specific optimization and evidence-based environmental assessment.

This study investigates the impact of soil pollution exposure on the physiological and cellular homeostasis of Pentodon bispinosus larvae. The beetle larvae were collected from two distinct environments: an organic site (control) and a chemical-treated site (insecticides & mineral fertilizers). The larvae were subjected to physiological, biochemical, histological, and ultrastructural analyses to evaluate stress markers, DNA damage, cell viability, and morphological changes. SEM-EDX microanalysis revealed elemental variations in larval midgut from treated soil. Apoptosis and necrosis were measured, a significant differences in cell viability observed between the polluted and control groups. Comet assay was utilized to assess DNA damage, showing increased genotoxic effects in the treated group. Biochemical assays for oxidative stress markers, including ALT, AST, MDA, SOD, CAT, GPx, and APOX, indicated a higher oxidative burden in larvae from polluted soil. Statistical analysis revealed significant physiological and biochemical disruptions in the treated larvae, supporting the hypothesis that soil pollution exposure adversely affects cellular and molecular integrity, leading to potential disturbances in homeostasis. Histological and ultrastructural examinations demonstrated cellular disruptions in the larvae exposed to polluted soil. This research unveils and highlights the novel impacts of soil pollution on the larvae of white grub beetle, with implications for ecosystem health, and the potential use of these larvae as a promising assessment bioindicator for soil pollution.