Plant Pathogenic Bacteria Transmission and Biofilm Life Cycles Influenced By Fluid Dynamics inside Insect Mouthparts and Plant Xylem

Xylella fastidiosa is a global plant pathogenic bacterium vectored between plants by sharpshooter leafhoppers (Hemiptera: Cicadellidae: Cicadellinae) and other insects. The bacteria forms biofilms in plant xylem and insect mouthparts. There are varying hypotheses for mechanisms of X. fastidiosa transmittal reported in the literature. In this poster, transmittal via flow driven detachment mechanisms is supported by comparing 3D fluid dynamic simulations with previously reported colonization patterns of insect mouthparts. These simulations were developed for both grapevine xylem and the blue-green sharpshooter mouthparts. Results are combined with an estimate for water hammer to infer a cohesive narrative on X. fastidiosa acquisition, transmission, and biofilm formation. Based on the model, acquisition and transmission are likely to occur during sharpshooter X wave feeding behaviors. This novel mechanistic understanding clarifies reasons for previously reported transmission variables while emphasizing new targets for disease prevention.