Comparison of Bacterial Communities of Flower Thrips (Frankliniella tritici) and Potato Psyllid (Bactericera cockerelli)

The potato psyllid, Bactericera cockerelli (Sulc), is the primary insect vector of the bacterium Candidatus Liberibacter solanacearum Leifting et al., the causal agent of zebra chip disease in solanaceous crops. Some phloem-feeding insects harbor bacterial communities determined by the food sources of the insects. Horizontal transmission of bacteria between individuals of the same species and insects of different species, with their host plants as reservoirs occurs in several plant insect systems. Ca. L. solanacearum is symbiotic in potato psyllid and can colonize plants before transmitted to its next insect host. Flower thrips, Frankliniella tritici (Fitch), that co-colonize plants have tested positive for Ca. L. solanacearum, although vector status is unknown. The bacterial community of thrips co-colonizing plants infected with Ca. L. solanacearum was analyzed and compared to that of potato psyllids on the same plants. Bacterial communities of samples were sequenced via the Illumina MiSeq platform and analyzed with macQIIME. Of the three thrips samples subjected to 16s bacterial community sequencing, the bacterium Ca. L. solanacearum comprised 6, 1, and 3% of their total bacterial community; of the three psyllid samples screened it comprised 1, 43, and 20% of the total bacterial community. This suggests that thrips can harbor the bacterium Ca. L. solanacearum.