«Aztec» – the new white table grape resistant variety

It is well known that free varietal thiols, in particular 3-mercaptohexanol (3MH) and 3-mercaptohexyl ace-tate (3MHA), are important constituents to the aroma of New Zealand Sauvignon blanc wines.

With contemporary climate change, cultivated Vitis vinifera L. is at risk as climate is a critical component in defining ecologically fitted plant materiel. While winegrowers can draw on the rich diversity among grapevine varieties to limit expected impacts (Morales-Castilla et al., 2020), replacing a signature variety that has created a sense of local distinctiveness may lead to several challenges. In order to sustain wine identity in uncertain climate outcomes, the study of intra-varietal diversity is important to reflect the adaptive and evolutionary potential of current cultivated varieties. The aim of this ongoing study is to understand to what extent can intra-varietal diversity be a climate change adaptation solution. With a focus on early (Sauvignon blanc, Riesling, Grolleau, Pinot noir) to moderate late (Chenin, Petit Verdot, Cabernet franc) ripening varieties, data was collected for flowering and veraison for the various studied accessions (from conservatory plots) and clones. For these phenological growing stages, heat requirements were established using nearby weather stations (adapted from the GFV model, Parker et al., 2013) and model performances were verified. Climate change projections were then integrated to predict the future behaviour of the intra-varietal diversity. Study findings highlight the strong phenotypic diversity of studied varieties and the importance of diversification to enhance climate change resilience. While model performances may require improvements, this study is the first step towards quantifying heat requirements of different clones and how they can provide adaptation solutions for winegrowers to sustain local wine identity in a global changing climate. As genetic diversity is an ongoing process through point mutations and epigenetic adaptations, perspective work is to explore clonal data from a wide variety of geographic locations.

Aims: Agroscope investigated the efficiency of nitrogen fertilization via foliar urea application at veraison with the aim of raising the YAN (yeast assimilable nitrogen) content in the musts. The observations were conducted on the white grapevine cultivar Doral (Chasselas x Chardonnay) in several pedoclimatic conditions of the Leman wine region, Switzerland, in the years 2012 and 2013. Knowing that the YAN in must plays a key role in wine quality, the aim was finding the main parameters affecting the final YAN level in order to better control them.

Among the Vitis vinifera L. cv. Moscato, Moscato Bianco is the oldest and most cultivated one in Europe (1). According to the OIV Focus 2015, Italy is the country with the largest cultivated area of Moscato Bianco with about 12500 hectares (2), that is used to produce well-known wines (i.e., Moscato Passito in Piedmont, Moscato di Trani in Puglia, and Moscatello di Montalcino in Tuscany), mainly obtained from partially dehydrated grapes (1). Different dehydration techniques can strongly modify the chemical compounds of oenological interest, among which Volatile Organic Compounds (VOCs) (1) that are the main responsible for the varietal sensory character of the final wine.

Multispectral unmanned aerial vehicle (UAV) has been successfully applied in monitoring vine vegetative growth, however, there are still potential relationships between remote sensing vegetation indexes (vis) and vine condition or grape quality, so it is worthy a deeper investigation to make a better use of UAV. One of the purposes of the study is to find out vis that could denote the severity of downy mildew (DM), so that precise and differentiated control strategies would be adopted subsequently.