Grape phylloxera, Daktulosphaira vitifoliae (Fitch), is the most important insect pest of grape and continues to impact the world’s vineyards. It is native to North America but has spread to every region where grapes are grown, causing billions of dollars in damage by feeding on the roots. Rootstocks, bred from resistant North American grape species, have been used to control phylloxera for over 100 years, but rootstocks with partial Vitis vinifera parentage now fail to phylloxera. This project focuses on the phylloxera resistance of the American grape V. rupestris and the susceptibility of V. vinifera by examining progeny from a remake of the rootstock AXR#1 (V. vinifera ‘Aramon' X V. rupestris ‘Ganzin’). The number and type of root gall formed in response to phylloxera may be associated with a plant’s level of resistance. Plants from the F1 generation were selected for a series of sibling crosses among resistant and susceptible individuals as well as backcrosses to ‘Aramon’ and ‘Ganzin’. A subset of the resulting F2 progeny was selected from these crosses and infested to identify resistant and susceptible plants and to determine inheritance of gall formation. Preliminary data suggest that more than one gene is likely responsible for gall formation, and hence resistance or susceptibility. Marker analysis is also in progress to correlate ISSR, AFLP, and SSR markers with resistance and susceptibility and to create a linkage map. These markers will be useful in resistance breeding and serve as the basis for more detailed studies of resistance mechanisms in Vitis.
Species 1: Homoptera Phylloxeridae Daktulosphaira vitifoliae (grape phylloxera)
Keywords: Vitis species, molecular markers
The ESA 2001 Annual Meeting - 2001: An Entomological Odyssey of ESA