Metagenomic analysis reveals Ca. Phytoplasma spp. in Empoasca fabae indicating ability to vector multiple species

Leafhoppers (Cicadellidae) are among the largest insect families within Hemiptera and pose a significant threat to agricultural crops worldwide. Canada serves as a hotspot for Nearctic leafhopper species, harboring approximately 35% of the reported diversity. The changing climate has profound implications for these insects, suggesting potential shifts in their population dynamics across the Canadian Nearctic range. Certain Cicadellidae species, such as the migratory leafhopper Empoasca fabae, are highly polyphagous, damaging various crops while also acting as vectors for plant pathogens. Among these pathogens, phytoplasmas—obligate bacteria transmitted by leafhoppers—can cause malformations in plant reproductive structures, thereby posing risks to crop yields.In this study, we analyzed Illumina sequencing data from E. fabae specimens collected in southwestern Québec. An initial metagenomic analysis using Kraken2 taxonomic classification indicated that E. fabae may act as a vector for multiple phytoplasma species. Molecular cloning of the 16S rRNA region confirmed the presence of two distinct phytoplasma species within the samples. This study represents the first report of multiple ‘Candidatus Phytoplasma’ species in the migratory leafhopper E. fabae. Our findings underscore the importance of understanding leafhopper-mediated transmission dynamics, particularly in the context of climate change and shifting migratory patterns.