Spatial Genetic Structure of a Vector-Borne Generalist Pathogen

Abstract

Vector-borne generalist pathogens colonize several reservoir species and are usually dependent on polyphagous arthropods for dispersal; however, their spatial genetic structure is generally poorly understood. Using fast-evolving genetic markers (20 simple sequence repeat loci, resulting in a total of 119 alleles), we studied the genetic structure of the vector-borne plant-pathogenic bacterium Xylella fastidiosa in Napa Valley, CA, where it causes Pierce's disease when it is transmitted to grapevines from reservoir plants in adjacent

Temporal and Spatial Scaling of the Genetic Structure of a Vector-Borne Plant Pathogen

“…After DNA denaturation for 5 min at 95°C, followed by cooling in ice for 2 min, samples were submitted to capillary electrophoresis in an ABI 3730xl DNA sequencer (Life Technology) with the LIZ500-3730 standard setting on GeneScan module with filter set G5. Data capture from sequencer and analysis of allele size followed previously described methodology (10).…”

“…Fourteen SSR loci were used to type isolates, based on repeats previously identified (Supplemental Table 1) (10,31). We used polymerase chain reactions (PCRs) with three or four multiplexed primer sets each.…”

“…Fast-evolving simplesequence DNA repeat (SSR) markers were used, because they have been previously shown to provide adequate resolution for X. fastidiosa populations (10). These analyses provide information on the genetic diversity of field populations, as well as the consequences of vector transmission of X. fastidiosa on the structure of these populations.…”

Genomic Insights into Xylella fastidiosa Interactions with Plant and Insect Hosts

“…Several short sequence repeats (SSR) have been identified in the chromosome (ColettaFilho et al 2001). These loci tend to evolve quickly, and several have been confirmed as having variable number of tandem repeats (VNTR), making them useful for high-resolution studies of population structure (Coletta-Filho et al 2011). …”

Spatial Genetic Structure of Coffee-Associated Xylella fastidiosa Populations Indicates that Cross Infection Does Not Occur with Sympatric Citrus Orchards

“…AMOVA showed that 56% of the variance was attributed to within-population and 44% to among-population variability, reflecting a high value of genetic differentiation at the population level (F STAT = 0.44, P £ 0.01). Similarly to others studies with X. fastidiosa in citrus Coletta-Filho et al 2014), and grapevine (Coletta-Filho et al 2011), no correlation was found between genetic differentiation index (D est and R ST ) and geographical distances among populations using the Mantel test (r = 0.012, P = 0.50). Based on a Bayesian clustering analysis used to infer the number of genetically homogeneous groups, three subpopulations (K = 3) were identified (Fig.…”