Field performance of fungal resistant crop varieties under diverse integrated pest management approaches in northern Spain

Abstract

Grapevine production in the EU faces increasing pressure from climate change, high pesticide dependence, and the need to maintain grape and wine quality while reducing environmental impact. Within this context, the SHIELD4GRAPE project aims to develop sustainable Integrated Pest Management (IPM) strategies and exploit resilient or resistant grapevine genotypes to reduce reliance on synthetic fungicides against downy mildew (DM), powdery mildew (PM) and trunk diseases.

This study focused on grapevine disease management through the combined use of powdery and downy mildew-resistant varieties and low-risk plant protection products. The objective was to assess the impact on yield, vine balance, disease control, and oenological traits of two treatments (orange oil and potassium bicarbonate, and Cu and S were used as controls) in two resistant varieties, with Viura included as a susceptible control, across two experimental locations (Valdegón and Arkaute). The interaction between variety, treatment, and environment was also evaluated.

Treatments significantly influenced must and wine composition. Linear discriminant analysis, using treatment as the grouping factor, clustered samples with the same treatment together in the two-dimensional representation. In must samples from Valdegón, the orange oil treatment increased yeast assimilable nitrogen (YAN) in resistant varieties, while wines produced under this treatment showed lower alcohol content and volatile acidity. Wines from Cu–S treatments exhibited lower malic acid concentrations, whereas those treated with potassium bicarbonate showed higher total SO₂ levels. In the Arkaute samples, the IPTs were much higher for the Cu-S treatment, and the tartaric acid and volatile acidity was lower in the samples treated with orange oil.

Multivariate analysis of variance (MANOVA) demonstrated a notable interaction between variety and location, yield-related parameters were consistently higher in Valdegón compared to Arkaute. YAN value in the musts and the ethanol content in wines were also different between the two locations. The interaction between variety and treatment was not significant for either the productivity variables or the physicochemical parameters of the must or wine.

Implications of these results will be further discussed. The expected results will help the transition to a more diverse, environmentally-safer viticulture in the EU.

Acknowledgements

This work was supported by the European Commission in the frame of the Horizon Europe program, project ‘Shield4Grape’ (grant agreement number 101135088). Views and opinions expressed are those of the authors only and do not necessarily reflect those of the European Union. Neither the European Union nor the granting authority can be held responsible for them.