| effects of temperature on the flight activity of graphocephala atropunctata (hemiptera: cicadellidae). | graphocephala atropunctata (signoret) is the principal vector of xylella fastidiosa (wells, raju, hung, weisberg, mandelco-paul and brenner), the bacterium that causes pierce's disease of grapevine in coastal california. monitoring the activity of c. atropunctata in the early spring is important for timing insecticide sprays and assessing the potential for disease spread to adjacent vineyards. trapping studies with yellow sticky traps over 3 yr in napa valley, ca, established a significant corre ... | 2000 | 14658516 |
| effects of date of inoculation on the within-plant movement of xylella fastidiosa and persistence of pierce's disease within field grapevines. | abstract the effects of date of inoculation on the development of pierce's disease (pd) were evaluated in california grapevines during 1997 through 2000 at four locations. some vines that had been inoculated either by using blue-green sharpshooters (graphocephala atropunctata) as vectors or mechanically by needle puncture with the pd causal bacterium xylella fastidiosa became infected during each month and at each location where infection was attempted. vines inoculated on the earliest inoculati ... | 2003 | 18943140 |
| differential genome evolution between companion symbionts in an insect-bacterial symbiosis. | obligate symbioses with bacteria allow insects to feed on otherwise unsuitable diets. some symbionts have extremely reduced genomes and have lost many genes considered to be essential in other bacteria. to understand how symbiont genome degeneration proceeds, we compared the genomes of symbionts in two leafhopper species, homalodisca vitripennis (glassy-winged sharpshooter [gwss]) and graphocephala atropunctata (blue-green sharpshooter [bgss]) (hemiptera: cicadellidae). each host species is asso ... | 2014 | 25271287 |
| de novo transcriptome assemblies of four xylem sap-feeding insects. | spittle bugs and sharpshooters are well-known xylem sap-feeding insects and vectors of the phytopathogenic bacterium xylella fastidiosa (wells), a causal agent of pierce's disease of grapevines and other crop diseases. specialized feeding on nutrient-deficient xylem sap is relatively rare among insect herbivores, and only limited genomic and transcriptomic information has been generated for xylem-sap feeders. to develop a more comprehensive understanding of biochemical adaptations and symbiotic ... | 2017 | 28327966 |
| diffusible signal factor-repressed extracellular traits enable attachment of xylella fastidiosa to insect vectors and transmission. | the hypothesis that a wild-type strain of xylella fastidiosa would restore the ability of rpff mutants blocked in diffusible signal factor production to be transmitted to new grape plants by the sharpshooter vector graphocephala atropunctata was tested. while the rpff mutant was very poorly transmitted by vectors irrespective of whether they had also fed on plants infected with the wild-type strain, wild-type strains were not efficiently transmitted if vectors had fed on plants infected with the ... | 2014 | 24571393 |
| genetic structure of graphocephala atropunctata (hemiptera: cicadellidae) populations across its natural range in california reveals isolation by distance. | the genetic structure of 23 populations of graphocephala atropunctata (signoret) (hemiptera: cicadellidae: cicadellinae), a vector of the plant pathogenic bacterium xylellafastidiosa wells et al., was investigated using ribosomal 28s and mitochondrial cytochrome c oxidase i gene sequences. the 28s sequences were identical across all g. atropunctata specimens and populations, but 16 mitochondrial haplotypes were detected and significant interpopulation differences were found in the distribution o ... | 2011 | 21404869 |
| pierce's disease bacterium: mechanism of transmission by leafhopper vectors. | the bacterium that causes pierce's disease of grapevines is isolated most consistently from the foregut of its leafhopper vector graphocephala atropunctata. as seen in light and scanning electron microscopy of infective leafhoppers, the bacteria are attached to the cibarial pump and the lining of the esophagus in the foregut where they appear to multiply. these findings suggest that the bacterium is transmitted from the foregut by egestion during feeding by infective leafloppers. | 1979 | 17820765 |