FutureWheatProtein: Grain protein stability and agronomic performance of winter wheat under elevated CO₂ and drought

Climate change threatens both yield stability and grain quality in winter wheat (Triticum aestivum L.). Rising atmospheric CO₂ concentrations can increase biomass accumulation and grain yield. At the same time, grain protein content may decrease as increased carbon uptake is accompanied by reduced conversion of nitrate-N into leaf protein. Meanwhile, drought alters phenological development, plant growth, biomass formation, yield, and grain protein content. In the FutureWheatProtein project, we investigate the genotype-specific responses to elevated CO₂ and water limitation at physiological and genetic levels, with a particular focus on grain protein content and agronomic performance.
In controlled greenhouse experiments, we evaluate winter wheat genotypes under contrasting CO₂ levels and water availability conditions to characterise variation in development, growth, biomass, leaf carbon-to-nitrogen ratio, and grain protein content. We also conduct complementary experiments using the PlantArray facility, a lysimeter phenotyping system in which plants are grown under defined soil moisture while continuously monitoring plant water use. The system enables the dynamic study of drought responses, including changes in daily transpiration, water demand, and the timing of stress responses during early vegetative development. Together, these measurements provide a quantitative basis for identifying genotypes with contrasting water use patterns and drought responses.
Phenotypic data are combined with single nucleotide polymorphism (SNP) markers to identify QTLs associated with responses to elevated CO₂ and drought. Molecular markers are then developed, and candidate genes are identified within the corresponding genomic regions. Genotypes with contrasting responses identified under greenhouse conditions are evaluated in the field using the Free-Air CO₂ Enrichment (FACE) system, where the canopy is exposed to elevated atmospheric CO₂ in open-field conditions. By combining physiological phenotyping, genetic analysis, and field validation, FutureWheatProtein aims to identify genotypes, traits and genetic factors associated with maintaining grain protein content and agronomic performance under future climate conditions.