Vitis vinifera L. Fruit Diversity to Breed Varieties Anticipating Climate Changes

Abstract

The wine industry is facing critical issues due to climate changes since production is established on very tight Genotype × Environment interaction bases. While, some cultivation practices may reduce adverse effects of abiotic stresses on the vines, e.g., the use of irrigation to mitigate drought, the deleterious impacts of warming on fruit development are difficult to manage. Elevated temperature alters grapevine fruit growth and composition, with a critical increase of the sugars/organic acids ratio. Select grapes with improved metabolite balances to offset high temperature effects is a valuable option to sustain viticulture. Unfortunately, the lack of knowledge about the genetic diversity for fruit traits impacted by temperature impairs the design of breeding programs. This study aimed to assess the variation in berry volume, main sugars and organic acids amounts in genetic resources. Fruit phenotyping focused on two critical stages of development: the end of green lag phase when organic acidity reaches its maximum, and the ripe stage when sugar unloading and water uptake stop. For that purpose, we studied a panel of 33 genotypes, including 12 grapevine varieties and 21 microvine offspring. To determine the date of sampling for each critical stage, fruit texture and growth were carefully monitored. Analyses at both stages revealed large phenotypic variation for malic and tartaric acids, as well as for sugars and berry size. At ripe stage, fruit fresh weight ranged from 1.04 to 5.25 g and sugar concentration from 751 to 1353 mmol.L-1. The content in organic acids varied both in quantity (from 80 to 361 meq.L-1) and in composition, with malic to tartaric acid ratio ranging from 0.13 to 3.62. At the inter-genotypic level, data showed no link between berry growth and osmoticum accumulation per fruit unit, suggesting that berry water uptake is not dependent only on fruit osmotic potential. Diversity among varieties for berry size, sugar accumulation and malic to tartaric acid ratio could be exploited through cross-breeding. This provides interesting prospects for improving grapevine to mitigate some adverse effects of climate warming on grapevine fruit volume and quality.

Cutting the Gordian Knot of abiotic stress in grapevine: From the test tube to climate change adaptation

“…Overall, the enhanced response of stress‐related metabolites, such as trehalose, stilbene and abscisic acid (ABA) in ‘Shiraz’ berry‐skin are consistent with its relatively higher susceptibility to environmental cues than ‘Cabernet Sauvignon’ (Degu et al ). The knowledge of these physiological modulations by the environment led to the recent research suggesting the use of cross‐breeding to exploit the diversity among varieties for berry size, sugar accumulation and malic to tartaric acid ratio and develop new varieties able to withstand adverse effects of climate warming on berry volume and quality (Bigard et al ). In experiments performed in Montpellier, France, irrigated and nonirrigated plants of different varieties were analyzed for berry size and composition and a huge variability in the contents of malic and tartaric acids were found, together with some correlation with berry growth (Bigard et al ).…”

Impact of agronomic practices on grape aroma composition: a review

“…[12][13][14][15][16][17][18][19][20][21][22][23][24] Understanding how these factors affect grapes' composition is critical to developing strategies for adapting viticultural practices to climate change. [25][26][27] Plant volatile compounds (VOCs), which are determined by the variety and may be influenced by vineyard management and biotic or abiotic stresses, have a key role in grape quality. They are secondary metabolites, and, as shown in previous research on phenolic compounds, 28 agronomic practices can influence the content and profile of secondary metabolites in two different ways: directly, where biosynthesis of the molecules changes as a result of agronomic practice, and indirectly, as a consequence of a variation in the concentration of the molecules, due to changes in the fruit volume and weight.…”

Genome-wide association and prediction study in grapevine deciphers the genetic architecture of multiple traits and identifies genes under many new QTLs

“…This is a particularly pressing issue for grapevine due to the strong intra-and inter-cluster heterogeneity between berries (Shahood, 2017). New protocols were proposed, requiring temporal sampling, but work remains to be done to automatize them allowing the phenotyping of a large number of genotypes (Bigard et al, 2018).…”