Evaluation of susceptibility to powdery mildew (Erysiphe necator) in Vitis vinifera varieties

Susceptibility to grape powdery mildew ( Erysiphe necator Schwein.) was studied in 159 Vitis vinifera foreign and native grape varieties grown in Spain. The relationship between morphological features of vines and their susceptibility to the disease was also studied. The infection was evaluated under natural conditions on leaves and bunches. A total of 35 cultivars were very susceptible to the disease (very low to low resistance on bunches), while another 83 showed low susceptibility (high to very high resistance on bunches). Results provide useful information for grape growers and breeders for the selection of varieties less susceptible to powdery mildew.