Figure 6.

Overview of demonstrated transmission routes in the L. villosa – Burkholderia symbiosis. The beetles can transmit the reduced-genome symbiont Lv-StB vertically, as well as horizontally to plants. In addition, they can transmit unidentified B. gladioli strain(s) to leaf litter. Lv-StA, the culturable strain without signs of genome erosion, is capable of infecting and surviving in different plant hosts and can be acquired from the leaf litter by the insect. The numbers in parenthesis indicate the section of the manuscript, or the published reference, in which evidence for each transmission route is provided.