Multi-Omics Analysis of Bombyx batryticatus Formation Reveals Strain-Dependent Host Molecular Responses and Biomass Variation

Bombyx batryticatus is a traditional Chinese medicinal material derived from Bombyx mori infected by Beauveria bassiana; however, its formation mechanism remains poorly understood. This study compared infection processes in silkworms by two B. bassiana strains with markedly different virulence (highly virulent ZY027 and ARSEF2860). Integrated transcriptomic and proteomic analyses were employed to uncover, for the first time, the molecular basis of B. batryticatus formation at the systems biology level. The results demonstrated significant weight variations in B. batryticatus derived from different fungal strains. ZY027-induced stiff silkworms exhibited higher wet and dry weights than those infected by ARSEF2860. Large-scale gene reprogramming occurred in silkworm hemolymph post-infection, involving marked activation of Toll/Imd immune signaling pathways, ribosome biogenesis, and endoplasmic reticulum stress responses. A notable “uncoupling” between transcriptomic and proteomic profiles was identified, highlighting the critical role of post-translational regulation in host responses. The two strains triggered distinct metabolic reprogramming patterns: ZY027 notably suppressed oxidative phosphorylation and activated detoxification mechanisms, whereas ARSEF2860 presented characteristics of “immune–metabolic optimization.” These findings suggest that B. batryticatus formation involves complex fungus–silkworm molecular interactions in hemolymph, and that fungal strain characteristics are associated with significant differences in host molecular responses and product biomass. The study provides a theoretical foundation and innovative guidance for selecting strains with high B. batryticatus production potential and developing novel entomopathogenic fungal resources.