Induced resistance as a strategy for vineyard protection

National audience

Inglés. As most grown grapevine <em>Vitis vinifera</em> varieties are susceptible to diseases such as downy and powdery mildews, numerous treatments are required to ensure a satisfactory yield and harvest quality. However, the use of phytochemical fungicides has serious drawbacks: some of them are potentially harmful for the environment and human health and contribute to the selection of resistant pathogen strains. Nowadays, in an objective of sustainable viticulture, there is increasing societal request, political incitation and winegrower’s awareness to reduce the use of pesticides. For these reasons, alternative strategies of protection are under research. In our laboratory, we are studying one alternative consisting in the activation of the grapevine defense reactions by compounds called elicitors. Plants are almost constantly in contact with potentially pathogen microorganisms such as oomycetes, fungi or bacteria. However, due to defense mechanisms, disease is finally an exceptional outcome in plant-pathogen interactions. General elicitors are compounds of different biochemical families capable of inducing plant defense reactions. Their perception by the plant triggers signaling events that allow the activation of defense genes encoding PR proteins and other proteins involved in phytoalexin production and cell wall reinforcement. Elicitors possess a potentially high interest for crop protection since they can not only elicit defenses in a broad spectrum of plants, but are also mostly deprived of toxicity and suitable for industrial production from abundant sources. Such a strategy could therefore be included in an integrated pest management or biological control strategy. We propose to sum up the main axis of our research about elicitors and the identification of the key mechanisms involved in induced resistance against downy mildew.