Extraction, stabilization and analysis of stilbenoid-rich grape cane extracts and their effects on Plasmopara viticola, causal agent of downy mildew, in greenhouse and vineyard studies

Organic viticulture seeks eco-friendly alternatives to copper fungicides used against Plasmopara viticola, the causal agent of downy mildew. This dissertation explores the use of grape cane - an underutilized byproduct rich in stilbenoids - for producing bio-based pesticides.
This work investigates stilbenoid variability across cultivars, vintages, and environmental conditions, and addresses challenges in extract stabilization, such as photo-induced isomerization. It introduces protective additives and applies cutting-edge HPLC-TIMS-MS to identify degradation pathways. A ligninsulfonate-based grape cane extract formulation was developed and patented, showing strong antifungal activity alone and in synergy with copper or apple extracts. Greenhouse and field trials confirmed its efficacy without compromising berry quality.
The findings support the valorization of grape cane as a sustainable tool in disease management and organic farming.