ARS | Publication request: POPULATION STRUCTURE AND DIVERSITY OF EUTYPA LATA FROM MEDITERRANEAN GRAPE-GROWING REGIONS

Submitted to: Phytopathology
Publication Type: Abstract Only
Publication Acceptance Date: May 5, 2009
Publication Date: August 1, 2009
Citation: Travadon, R., Baumgartner, K., Rolshausen, P., Sosnowski, M.R., Trouillas, F., Gubler, W. 2009. POPULATION STRUCTURE AND DIVERSITY OF EUTYPA LATA FROM MEDITERRANEAN GRAPE-GROWING REGIONS. Phytopathology. 99:S108.

Technical Abstract: Eutypa lata is an ascomycete fungus causing dieback of grape (Vitis vinifera). We examined the genetic structure of eight vineyard collections using nine polymorphic microsatellite loci. In California, isolates were collected from four vineyards (CS1, CS2, M1 and M2) separated by distances of 50 m to 21 km. In Australia, isolates were collected from four vineyards (CS3, Sh1, Sh2 and Sh3) separated by distances of 80 to 410 km. Among the 145 isolates analyzed 134 unique multilocus haplotypes were identified based on unique combinations of alleles among the microsatellite loci. Among all vineyards, gene diversity (H=0.56 to 0.62) and genotypic diversity (G=0.85 to 1) were high, and there was no linkage disequilibrium among loci (P<0.01). We found that >93% of genetic variance was found within vineyards (P<0.01) and 3.24% of variance could be attributed to differences among continents (P<0.05). Three pairwise comparisons revealed significant genetic differentiation between continents: Sh3 vs. both CS2 and M2 (FST=0.03 and 0.10, respectively; P<0.05), and Sh2 vs. M1 (FST=0.05; P<0.05). These findings, coupled with our finding of moderately low genetic differentiation between continents (FST=0.03; P<0.05), suggest that E. lata collections are part of a single panmictic population at the regional scale within continents, and gene flow is restricted between the two continents.