VvRefPanel field trial reveals new genetic determinants for abiotic stress tolerance in Vitis vinifera

Abstract

Despite the urgent need for boosting grapevine breeding to face the threat of climate change, the genetic determinism of key traits related to phenology and leaf physiology have yet to be explored in a large diversity panel in the field. To fill this gap, we established near Narbonne (South of France) a representative panel of > 250 V. vinifera varieties, the VvRefPanel, in four randomized complete blocks. We measured budburst, flowering and veraison dates, as well as traits related to carbon gain and water loss at the leaf level, including morphological and ecophysiological traits. We performed GWAS with resequencing data and millions of markers. We found several new phenology QTLs, most with limited individual effects.

For leaf traits, the QTLs detected in the field experiment differed from those previously found in a greenhouse experiment involving the same panel. However, multi-environment GWAS revealed shared QTLs with similar or opposite effects across experiments. These results emphasize the potential of this large diversity field trial, but also of joint analysis in several environments, to decipher the genetic architecture of key traits useful for breeding better adapted grapevine varieties.

Acknowledgements

These studies have been funded through the “Key Initiative Muse” (University of Montpellier, France), the “key challenge Vinid’Occ” (funded by French Occitanie Region and led by the University of Montpellier), the FruitRescue project (BNP Paribas foundation), the G2WAS project (French National Research Agency) and Institut Agro Montpellier. We thank all the other persons also involved in plant establishment, management and phenotyping, from CA11, UE Vassal, UMR AGAP Institut, UE PR and UMR LEPSE.