Table 4

Population structure of Erysiphe necator by geographic region and host species.

Populations compared (sample sizes are in parentheses)

Snn1

HST1


Eastern US (103) vs. introduced (43) populations

0.9182

(< 0.001)

0.0627

(< 0.001)

Within the eastern US

by geographic region

northeast (59) vs. southeast (34) vs. central (10)

0.6856

(< 0.001)

0.0280

(< 0.001)

by geographic region on Vitis vinifera and vinifera hybrid hosts

northeast (33) vs. southeast (15) vs. central (9)

0.6384

(< 0.001)

0.0396

(0.001)

by host agro-ecological habitat2

cultivated (59) vs. wild (34) hosts

0.5733

(0.133)

0.0002

(0.407)

by host species within the northeast US

V. vinifera (13) vs. vinifera hybrid (20) vs. V. labrusca (10) vs. V. riparia (8)

0.3532

(0.064)

0.0051

(0.333)

by host species within the southeast US including V. rotundifolia3

V. rotundifolia (5) vs. V. vinifera (11) vs. vinifera hybrid (4) vs. V. labrusca (3) vs. V. aestivalis (9)

0.3529

(0.008)

0.0857

(0.007)

by host species within the southeast US excluding V. rotundifolia

V. vinifera (11) vs. vinifera hybrid (4) vs. V. labrusca (3) vs. V. aestivalis (9)

0.2552

(0.712)

-0.0179

(0.709)


1The nearest neighbour statistic (Snn) measures the proportion of times the most similar sequence ('nearest neighbour') is from the same population [67]. HST is a measure of population subdivision that estimates FST among haplotypes [68]. Significant differentiation between or among populations (α = 0.05) is shown in bold. P-values are in parentheses.

2Isolates from the central US were excluded because all but one were from cultivated species.

3A single isolate from V. riparia was excluded from the southeast population.

Brewer and Milgroom BMC Evolutionary Biology 2010 10:268   doi:10.1186/1471-2148-10-268

Open Data