Vineyard damage due to grape phylloxera, Daktulosphaira vitifoliae Fitch, has been controlled by resistant rootstocks for over 100 years. There are now a wide range of rootstocks used in California vineyards since the collapse of AXR#1. To study the effect of this rootstock diversity on phylloxera genetics and possible host adaptation, a set of microsatellite primers were developed to augment the four produced by Corrie and colleagues (2002). In order to develop more microsatellite loci to improve the sensitivity and effectiveness of these markers for use in genetic diversity and rootstock adaptation studies, a subtractive-based hybridization strategy was used to construct microsatellite enriched genomic libraries from grape phylloxera DNA. Fifty loci were identified for primer design. Nineteen produced good PCR products, seven of which reliably detected polymorphisms across the 32 grape phylloxera populations tested. These seven SSR loci were used to distinguish genetic diversity in California and European grape phylloxera populations. Results confirm the utility of these loci for analyzing genetic diversity, “finger-printing” strains, and studying host associations. A significant deviation from the Hardy-Weinberg equilibrium for the tested California populations suggests that parthenogenesis is perhaps the primary, if not only, reproductive system in California.
- Copyright © 2006 by the American Society for Enology and Viticulture