Composition of the Gut Microbiome and Its Response to Rice Stripe Virus Infection in Laodelphax striatellus (Hemiptera: Delphacidae)

The small brown planthopper (SBPH), <i>Laodelphax striatellus</i>, transmits rice stripe virus (RSV), a devastating pathogen that causes significant yield losses in rice. The components of the gut microbiota in SBPH and the effects of RSV infection on gut microorganisms are unclear. In this study, high-throughput sequencing of 16S rRNA was utilized to evaluate the composition of gut microorganisms in SBPH. The gut microbiota of SBPH was primarily composed of Proteobacteria, Firmicutes and Bacteroidetes at ratios of 94.79%, 3.04% and 1.39%, respectively; furthermore, the composition of bacteria in the gut microbiota was relatively conserved with differences at the genus level. To elucidate the response of the SBPH gut microbiota to RSV infection, we compared its composition and abundance in viruliferous and naïve SBPH. Interestingly, RSV infection was associated with increased diversity in the SBPH gut microbiota. Comparative analysis demonstrated that RSV infection elevated the relative abundance of Proteobacteria while reducing that of Firmicutes. Population counts demonstrated that RSV infection reduced the gut loads of <i>Stenotrophomonas</i>, <i>Brevundimonas</i>, and <i>Brevibacillus</i>, whereas the gut load of <i>Staphylococcus</i> was significantly increased. Further functional predictive assays revealed that RSV infection enhanced the functions of the SBPH gut microbiota in terms of metabolism, cellular processes, genetic and environmental information processing, and organismal systems. Our results indicate that RSV reshapes the composition, abundance, and functions of the SBPH gut microbiota, offering insights into virus-host-microbiome interactions.