Fig 2. Simulated drag forces acting on individual, surface-attached bacteria in grapevine xylem vessels.
‘Egestion’ and ‘Ingestion’ indicate simulated fluid flow for insect-xylem interactions during these respective activities. ‘Undisturbed’ indicates simulated undisturbed xylem vessels by modeling the water tension gradient as a pressure gradient. The ** symbols on the y-axis are references to key drag forces in the results of a previous microfluidic study [29]. The blue horizontal line is a visual aid at 101.2 pN (15.85 pN) that represents the drag force where less than 1% of individually surface-attached Xylella fastidiosa cells detached in De la Fuente et al. [29]. When the drag forces in that same study were sequentially increased in our model, over 70% of X. fastidiosa detached by the time the drag forces reached 102.6 pN (443.8 pN) [29].