Infection levels of the petioles collected from +10 and +90 cm above the point of inoculation (POI) for each cultivar.

<p>Open bars refer to the infection levels at 10-cm above the point of inoculation. Filled bars represent the infection level of the petiole samples taken 90-cm above the point of inoculation. Error bars represent ±1 SE.</p

Variations in Spearman rho correlations between symptom severity and infection level of the 10 evaluated grape cultivars over time.

<p>Variations in Spearman rho correlations between symptom severity and infection level of the 10 evaluated grape cultivars over time.</p

Categorization of <i>Vitis vinifera</i> cultivars in relation to their bivariate X. fastidiosa infection level and symptom severity means at A) 8, B) 12, and C) 16 weeks post inoculation.

<p>Error bars represent 95% confidence intervals. Note that the scale of axes differ among panels.</p

Cultivar clusters on week 8 (A), week 12 (B), and week 16 (C) showing similarity in response to <i>X. fastidiosa</i> infection.

<p>Numbers represent approximate unbiased confidence values for a given node based on multiscale bootstrap resampling.</p

Relative prevalence of grapevine leafroll-associated viruses in tested vineyards.

<p>Data for individual vineyards in each of three regions are shown, with the number of positive plants and the total number of plants tested indicated on the right side of each column. Numbers in parentheses indicate the number of plants with mixed infections, if any. Acronyms; SLO, San Luis Obispo County; LODI, San Joaquin County; AMEL, Amador and El Dorado Counties.</p

Relative prevalence of grapevine leafroll-associated virus species by region.

<p>Data for the North Coast region were obtained from Sharma et al. 2011; GLRaV-7 was not tested in that survey. The map was generated by authors with R version 3.2.0.</p

Determining the geographic origin of invasive populations of the mealybug <i>Planococcus ficus</i> based on molecular genetic analysis

<div><p>Determining the most likely source of an invasive pest species might help to improve their management by establishing efficient quarantine measures and heading the search of efficient biological control agents. <i>Planococcus ficus</i> is an invasive mealybug pest of vineyards in Argentina, California, Mexico, Peru and South Africa. This mealybug pest had a previously known geographic distribution spanning southern Europe, the Middle East, and parts of northern Africa. In North America, <i>Pl</i>. <i>ficus</i> was first discovered in the early 1990s and soon thereafter in Mexico. To determine the origin of invasive populations in North America, <i>Pl</i>. <i>ficus</i> from California and Mexico were compared with material throughout its presumptive native range in the Mediterranean region, as well as material collected from an older invasion in South Africa and recently invaded Argentina. From each sample location, genomic DNA was sequenced for the nuclear internal transcribed spacer one (ITS1) and the mitochondrial cytochrome c. oxidase one (CO1). Phylogenetic analyses of CO1, ITS1 and concatenated CO1 and ITS1 data-sets using Bayesian and neighbor-joining analysis support two major divisions: a European grouping (Europe, Tunisia, Turkey) and a Middle Eastern grouping (Israel and Egypt). The invasive populations in Argentina and South Africa align with the European group and the invasive populations in North America align with the Middle Eastern group, with one Israel sample aligning closely with the North American clade, suggesting that Israel was the origin of those populations.</p></div

DNA sequence variation.

<p>DNA sequence variation.</p

Geographical distribution of the CO1 haplotypes for populations of <i>Planococcus ficus</i> collected in Europe, Africa, the Middle East, Argentina, California and Mexico.

<p>Geographical distribution of the CO1 haplotypes for populations of <i>Planococcus ficus</i> collected in Europe, Africa, the Middle East, Argentina, California and Mexico.</p

Neighbor-joining network of CO1 data.

<p>Haplotype network for the CO1 region for populations of <i>Planococcus ficus</i> collected in Europe, Africa, the Middle East, Argentina, California and Mexico. Each circle represents a different haplotype and the sizes of circles correspond to the number of individuals sharing this haplotype. Colors indicate sampling country. The crossbeam on the connecting lines between haplotypes represents a substitution. Black dots symbolize hypothetic haplotypes not sampled in the data set.</p