Exploring magnesium defficiency in Welschriesling grapevines: A multi-omics approach to address viticultural challenges

Abstract

Magnesium (Mg) deficiency poses a significant challenge to viticulture, particularly affecting Welschriesling (WR), a key grape variety in Austrian and Central European vineyards. This issue is especially pronounced in regions with light soils and sufficient precipitation, where Mg is easily leached, resulting in reduced photosynthesis, lower sugar content, and consequently, diminished vine health and wine quality. Existing WR clones exhibit limited Mg uptake efficiency, necessitating innovative solutions to identify genotypes that offer a better Mg uptake and metabolism.

Our interdisciplinary study aims to identify WR genotypes with enhanced Mg uptake efficiency and to uncover the genetic and epigenetic mechanisms underlying this trait. Combining cutting-edge bioinformatics, and a comprehensive multi-omics approach, we compared Mg-efficient (Mg+) and Mg-deficient (Mg-) clones across genetic, epigenetic, and transcriptomic levels.

Using PacBio long-read sequencing, we identified small variants with DeepVariant and structural variants with DeBreak, alongside assessing DNA methylation profiles via the IPDsummary tool. Gene expression analysis was performed with Illumina short-read sequencing, and Mg-related candidate genes were identified through weighted gene co-expression network analysis (WGCNA). A pivotal gene located on chromosome 11 potentially involved in Mg uptake efficiency, was among the identified candidates.

These insights lay the foundation for the development of biomarkers to distinguish Mg-efficient clones, enabling more targeted vineyard management strategies and contributing to the sustainability and resilience of viticulture. Furthermore, this research provides valuable insights applicable to other viticulture regions facing similar challenges, enhancing the global sustainability of grape production.