Changes in protein abundance during powdery mildew infection of leaf tissues of Cabernet Sauvignon grapevine (Vitis vinifera L.).

A comparative analysis of differentially expressed proteins in a susceptible grapevine (Vitis vinifera 'Cabernet Sauvignon') during the infection of Erysiphe necator, the causal pathogen of grapevine powdery mildew (PM), was conducted using iTRAQ. The quantitative labeling analysis revealed 63 proteins that significantly changed in abundance at 24, 36, 48, and 72 h post inoculation with powdery mildew conidiospores. The functional classification of the PM-responsive proteins showed that they are involved in photosynthesis, metabolism, disease/defense, protein destination, and protein synthesis. A number of the proteins induced in grapevine in response to E. necator are associated with the plant defense response, suggesting that PM-susceptible Cabernet Sauvignon is able to initiate a basal defense but unable to restrict fungal growth or slow down disease progression.