Geographical Survey of the Mycobiome and Microbiome of Southern California Glassy-winged Sharpshooters

The glassy-winged sharpshooter, Homalodisca vitripennis Germar, is an invasive xylem-feeding leafhopper with a devastating economic impact on California agriculture through transmission of the plant pathogen, Xylella fastidiosa . While studies have focused on X. fastidiosa or known symbionts of H. vitripennis , little work has been done at the scale of the microbiome (the bacterial community) or mycobiome (the fungal community). Here we characterize the mycobiome and the microbiome of H. vitripennis across Southern California and explore correlations with captivity and host insecticide-resistance status. Using high-throughput sequencing of the ribosomal internal transcribed spacer (ITS1) region and the 16S rRNA gene to profile the mycobiome and microbiome, respectively, we found that while the H. vitripennis mycobiome significantly varied across Southern California, the microbiome did not. We also observed a significant difference in both the mycobiome and microbiome between captive and wild H. vitripennis . Finally, we found that the mycobiome, but not the microbiome, was correlated with insecticide-resistance status in wild H. vitripennis . This study serves as a foundational look at the H. vitripennis mycobiome and microbiome across Southern California. Future work should explore the putative link between microbes and insecticide-resistance status and investigate whether microbial communities should be considered in H. vitripennis management practices.