Impact of training system and harvest date on berry qualityof Frontenac and Marquette grown in Quebec, Canada.

C. Provost1 (cprovost@cram-mirabel.com), F. Dumont1, É. Ouellet2, K. Pedneault21Centre de recherche agroalimentaire de Mirabel; 9850, rue de Belle-Rivière, Mirabel, Québec, J7N 2X8

2Centre de développement bioalimentaire du Québec; 1642, rue de la Ferme, Sainte-Anne-de-la-Pocatière, Québec, G0R 1Z0

ICCWS, Brighton, England, 26-28 May 2016

Northern wine production in Eastern Canada is dominated by cold-hardy, highly productive and vigorous interspecific hybrids. In Quebec, most of these varieties, including Frontenac and Marquette, are grown using vertical shoot positioning. However, seseveral studies showed that high-cordon systems have significant effects on yield and berry quality [1 -3]. Little is known about the impact of training system on in-depth berry chemistry of cold- hardy grape cultivars, especially on secondary metabolitesmetabolites such as volatile

Introduction

The impact of training system was more noticeable on Frontenac than Marquette, with TWC resulting in higher yield in Frontenac. Training system had little impact on juice composition, including anthocyanin extractability and volatile compound prprofile that were mostly affected by harvest date.

Conclusion

The authors wish to thank Richard Kamal and Stephano Campagnaro for their technical support. Funding for this project has been provided by Programme Innov’Action, a program derived from the agreement Cultivons l’avenir 2, concluded between Ministère de l’Agriculture, de l’Alimentation et des Pêcheries du Québec et Agriculture et Agroalimentaire Canada.

Acknowledgement[1] Provost, C. & Zerouala, L. 2012. Effet de trois modes de conduite sur les gels, maturité et rendement de quatre cépages rustiques. PSIH10-1-348.[2] Reynolds, A.G. & Vanden Heuvel, J.E. 2009. Influence of grapevine training systems on vine growth and fruit composition: a review. Am. J. Enol. Vitic. 60: 251-268.[3] Provost, C. & Pedneault, K. 2016. Organic wine production: Current practices for vineyard management and winemaking. Sci Hort. In press.

Reference

Table 2. Juice metrics

Frontenac. Titratable acidity decreased earlier in berries trained as VSP when compared to TWC in 2015 but not in 2014. In 2015, the level of total soluble solids was higher in berries from TWC compared to VSP, at both harvest dates.Marquette. The level of total acidity was rather influenced by the harvest period than the training system (2014). In 2015, no significant effect of treatments was noted on chemical parameters.

Table 1. Agronomic parameters

Frontenac. Clusters were heavier on TWC than on VSP for both years, leading to an higher yield in 2015. Berry weight was higher at early harvest in 2014.

Marquette. The effect of training system varied from a year to another. In 2014, yield was higher in TWC than in VSP. In 2015, TWC harvested early showed higher berry weight and higher yield compared to treatments harvested lately.

Frontenac Marquette

Figure 1. Biplot of the principal component analysis of juice metrics (basic chemistry, nitrogen compounds, extractable anthocyanin, and free volatile compounds) from Frontenac and Marquette berries trained as VSP (T1 = early harvest; T3 = late harvest; blue and yellow diamonds, respectively) and TWC (T2 = early harvest, T4 = late harvest; green and red diamonds, respectively). Variables are highlighted.

Principal component analysis of juice metrics from the year 2014 (including anthocyanins and free volatile compounds) showed a significant impact of harvest date (Fig. 1) for both varieties. Conversely, training system (VSP, TWC) showed little impact on juicejuice characteristics in the course of the 2014 season, for both varieties.

Agronomic parameters

Oenological parameters

Results

In order to increase our understanding of interspecific hybrid grapes physiology, an experimental design involving two hybrid varieties (Frontenac and Marquette) and two training systems (Top Wire Cord and Vertical Shoot Positioning) was implemented at the experimentalexperimental vineyard of Oka (QC, CA) in 2008.Grapes were harvest early (22 -23 °Brix) and late (24 - 26 °Brix).

Method Varieties

Frontenac

Marquette

Top Wire Cord (TWC)

Vertical Shoot Positioning (VSP)

TreatmentsAgronomic parametersCluster weightBerry weightYield/ plant

Juice metricsTotal soluble solidsTitrable aciditypHYANPhenolic compoundsVolatil compounds

Measures