Evolutionary Metabolomics Reveals Domestication-Associated Changes in Tetraploid Wheat Kernels

Area of Science:

• Plant genetics and breeding
• Agricultural science
• Metabolomics

Background:

• Domestication and breeding drive genetic changes in plant populations for adaptation to agriculture.
• Tetraploid wheat (Triticum turgidum L.) domestication involved distinct stages, including wild emmer, emmer, and durum wheat.
• Understanding metabolite changes during domestication is crucial for improving crop quality.

Purpose of the Study:

• To investigate the impact of selection on kernel metabolite content and relationships during tetraploid wheat domestication.
• To identify molecular signatures of selection for metabolic traits.
• To assess the role of wild and exotic germplasm in enhancing wheat quality.

Main Methods:

• Development of a methodological pipeline to detect selection signatures in molecular phenotypic traits (metabolites, transcripts).
• Analysis of 51 primary kernel metabolites across wild emmer, emmer, and durum wheat subspecies.
• Examination of metabolic correlation networks to understand restructuring due to domestication.

Main Results:

• Selection during emmer domestication (primary) was associated with a reduction in unsaturated fatty acids.
• Selection during durum wheat domestication (secondary) was linked to changes in amino acid content.
• Metabolite alterations were partially independent of other domestication-related kernel traits, indicating significant metabolic restructuring.

Conclusions:

• Domestication significantly reshaped wheat kernel metabolism, with distinct metabolite changes at different domestication stages.
• Selection signatures for metabolites provide insights into the evolutionary history of wheat.
• Wild and exotic wheat germplasm hold potential for improving nutritional and quality traits in modern wheat varieties.