A cool climate perspective on grapevine breeding: climate change and sustainability are driving forces for changing varieties in a traditional market

Abstract

A multitude of diverse breeding goals need to be combined in a new cultivar, which always forces to compromise. The biggest challenge grapevine breeders face is the extraordinarily complex trait of wine quality, which is the all-pervasive and most debated characteristic. Since the 1920s, Germany runs continuous grapevine breeding programmes. This continuity was the key to success and lead to various new cultivars on the market, so called PIWIs. Initially, introduced pests and diseases such as phylloxera, powdery and downy mildew were the driving forces for breeding. However, preconceptions about the wine quality of new resistant selections impeded the market introduction. These preconceptions are still echoing today and may be the reason in large parts of the viticultural community for: (1) ignoring substantial breeding progress, and (2) sticking to successful markets of well-known varietal wines or blends (e.g. Chardonnay, Cabernet Sauvignon, Riesling). New is the need to improve viticulture´s sustainability and to adapt to changing environmental conditions. Climate change with its extreme weather will impose the need for a change in cultivars in many wine growing regions. Therefore, a paradigm shift is knocking on the door: new varieties (PIWIs) versus traditional varieties for climate adapted and sustainable viticulture. However, it will be slow process and viticulture is politically well advised to pave the way to variety innovation. In contrast to the widely available PIWIs, competitive cultivars created by means of new breeding technologies (NBT, e.g. through CRISPR/Cas) are still decades from introduction to the market.

Information on disease resistance patterns of grape varieties may improve disease management

“…The vineyard is planted with 16 grape varieties, most of which have one or more loci conferring partial resistance to P. viticola (Rpv) and E. necator (Ren). Some of these varieties are also expected to have loci involved in the resistance to P. ampelicida (Rgb), but the presence of these loci has not been confirmed ( Töpfer and Trapp, 2022 ). The V. vinifera variety ‘Merlot’, which is known to be highly susceptible to DM, PM, GM, and BR, served as the positive control.…”

Phenotyping for QTL identification: A case study of resistance to Plasmopara viticola and Erysiphe necator in grapevine

“…Resistance phenotyping in the vineyard has been performed since the 19th century (Töpfer et al, 2011 ; Yobrégat, 2018 ; Töpfer and Trapp, 2022 ). Candidate vines in a vineyard are assessed starting in the 3rd-year post-planting.…”

“…DM and PM have devastating impacts on grapevine cultivation (Gessler et al, 2011 ; Gadoury et al, 2012 ). Long-lasting research has focused on strategies to control the pathogens of these two diseases (Pertot et al, 2017 ), including the introgression of resistance from wild grapevine accessions into elite wine grape cultivars (Töpfer et al, 2011 ; Merdinoglu et al, 2018 ; Yobrégat, 2018 ; Töpfer and Trapp, 2022 ).…”

Sexually-Driven Combinatorial Diversity in Native Saccharomyces Wine Yeasts

“…Global climate change is exerting an increasingly effect on grape composition, microbiology, chemistry and the sensory aspects of wine, warm regions being profoundly affected [23]. Consequently, the search of autochthonous S. cerevisiae strains adapted to heat-related fermentation stresses is becoming an important approach for making quality wines in these areas.…”