![]() ![]() Velocities in the precibaria of these sharpshooters were estimated by dividing time-averaged feeding/excretion rates by representative cross-sectional areas of the precibaria. Early attempts at modeling relied on average daily excretion rate as a proxy for ingestion, for both blue–green sharpshooters and glassy-winged sharpshooters 6, 13. Previous studies have modeled fluid flow in the sharpshooter functional foregut. Better understanding of these mechanisms will aid in interpretation of electropenetrography (EPG) data that is being used to select and breed crop varieties that can resist inoculation of the bacterium by its vectors (Backus, unpublished data). Both the acquisition and inoculation mechanisms involve fluid dynamics in the functional foregut (the narrow precibarium leading to the wider cibarium or food pump) during feeding behaviors 2, 11, 12. Xylella fastidiosa is later inoculated via egestion when the vector feeds on healthy grapevine xylem 9, 10. ![]() fastidiosa bacteria are acquired as fluid passes through and resides in the functional foregut, eventually to attach and form a biofilm. When sharpshooters ingest (take up through the stylets and swallow) xylem sap from an infected grapevine using their stylets, X. Thus, this vector species is used as a model for the present study. A native California vector, the blue–green sharpshooter, Graphocephala atropunctata (Signoret, 1854), has been used in several studies on the mechanism of X. Of the 2,313 catalogued sharpshooter species worldwide, 35 are reported vectors of X. The state of California alone spends $104 million a year to control X. This invasive, pathogenic bacterium causes $100′s of millions in agricultural losses annually worldwide from plant diseases on multiple continents, including olive quick decline syndrome in South America and Europe, citrus variegated chlorosis in South America, and Pierce’s disease of grape in North America 3. (Xanthomonadales: Xanthomonadaceae) during feeding 2. They transmit (acquire, retain, and inoculate) the xylem-limited bacterial pathogen Xylella fastidiosa Wells et al. Sharpshooter leafhoppers (Hemiptera: Cicadellidae: Cicadellinae) feed on plant tissues using their piercing-sucking mouthparts, termed stylets 1. Improved understanding of these processes could lead to new targets for preventing diseases caused by X. The 3D model can also be used in future fluid dynamic simulations to better understand acquisition, retention, and inoculation of X. The vivid 3D illustrations herein and supplementary interactive 3D figures are suitable resources for multidisciplinary researchers who may be unfamiliar with insect anatomy. The model is used to illustrate preexisting and newly defined anatomical terminology that is relevant for investigating fluid dynamics in the functional foregut of sharpshooters. Herein, a 3D model of the blue–green sharpshooter functional foregut is derived from a meta-analysis of published microscopy images. ![]() fastidiosa vector is the blue–green sharpshooter, Graphocephala atropunctata (Signoret, 1854). fastidiosa biofilm formation and fluid dynamics in the functional foregut of sharpshooters, which together result in egestion (expulsion) of fluids likely carrying bacteria. Bacterial acquisition and inoculation mechanisms are linked to X. This pathogen causes economically significant diseases in olive, citrus, and grapes on multiple continents. Sharpshooter leafhoppers (Hemiptera: Cicadellidae: Cicadellinae) are important vectors of the plant pathogenic bacterium Xylella fastidiosa Wells et al. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |