While foliar application of copper (Cu) containing fungicides can protect vines from fungal infections such as downy mildew (Plasmopara viticola), it can increase soil Cu content which increases disease susceptibility, especially in acidic soils. In this study, we hypothesized that lime (CaCO₃ + MgCO₃) addition may minimize Cu toxicity in vines by increasing pH and reducing Cu bioavailability. We applied two Cu (no Cu added, 50 mg Cu kg⁻¹) and three lime (no lime added, 1.5, 3.0 Mg ha⁻¹) quantities on a Typic Hapludalf soil. After 60 days, root, plant performance, and biochemistry were measured. As expected, high Cu content negatively affected growth, nutrient status, and metabolism of young vines. However, addition of 3.0 Mg ha⁻¹ lime raised the soil pH from 4.5 to 6.1, decreasing Cu toxicity effects in young vines. Thus, lime addition is an effective strategy in protecting young vines in soils with high levels of Cu. Graphical Abstract .

Five plant extracts traditionally used in organic and biodynamic farming for pest control and antifungal (downy mildew) disease management were selected after a farmer survey and analyzed for their chemical composition in LC-PDA-MS-MS and using adapted analytical method from food chemistry for determination of class of component (e.g., protein, sugar, lipids…). Their antifungal activity against Penicillium expansum, Botrytis cinerea, Botrytis allii, brown rot causing agents (Monilinia laxa and Monilinia fructigena), and grape downy mildew (Plasmopara viticola) was examined in vitro. White willow (Salix alba) and absinthe (Artemisia absinthium) ethanolic extracts were found to be the most effective in particular against Plasmopara viticola, with a total inhibition of spores germination when applied at 1000 mg/L. These extracts also showed a relatively low toxicity during preliminary ecotoxicological assays on Daphnia pulex. Extract from the bark of white willow contained some flavonoids, especially flavanones (eriodyctiol and derivates) and flavanols (catechins and derivates), as major compounds, whereas absinthe extract was rich in O-methylated flavanols and hydroxycinnamic acids. Thujone content in this extract was also determined by external calibration in GC-MS analysis, and its value was 0.004% dry extract.