Impacts of Developmental Stages and Infection Status on the Endogenous Microbial Community of *Oppiella nova* (Oribatid Mite) Based on 16S rRNA High-Throughput Sequencing

"This project focuses on exploring the effects of developmental stages and infection status on the structure and diversity of endogenous microbial communities in *Oppiella nova*, a dominant oribatid mite species in soil ecosystems. *Oppiella nova* individuals will be collected from natural forest soil and classified into three developmental stages (larva, nymph, adult) and two infection statuses (infected with target pathogens, non-infected). A total of 180 samples (30 replicates per group) will be prepared: after surface sterilization to eliminate environmental bacterial contamination, total microbial DNA will be extracted from whole-body homogenates of mites. The V3-V4 hypervariable region of the 16S rRNA gene will be amplified for high-throughput sequencing, a reliable molecular marker for bacterial community analysis due to its conserved and variable regions that enable species differentiation. Sequencing data will be processed to analyze bacterial taxa composition (phylum to species levels), alpha/beta diversity indices, and core microbial taxa. The study aims to clarify whether developmental stage-related physiological changes (e.g., molting) or pathogen infection reshape the endogenous microbial community of *Oppiella nova*, and to reveal potential symbiotic interactions between the mite and its associated microorganisms. The results will provide fundamental data for understanding the ecological adaptation mechanisms of oribatid mites mediated by microbiota."