Background: Cultivated wheat exists in two ploidies: allotetraploid pasta wheat and allohexaploid
bread wheat. Ploidy is known to modify plant metabolism, yet studies comparing metabolomic
profiles of allotetraploid and allohexaploid wheat are scarce.
Objective: To characterize the ploidy and metabolomic profiles of selected Afghan wheat landraces
collected in the 1960’s and preserved in Japan and elite wheat cultivars.
Methods: Ploidy was determined in cell nuclei of wheat seedlings using flow cytometry. Metabolic
profiles of polar compounds were obtained with 1H NMR. Metabolite identification was performed
with 2D NMR and comparison against databases.
Results: We identified allotetraploid and allohexaploid variants of wheat landraces collected in Afghanistan
half a century ago. 1H NMR metabolomics discovered a separation between the allotetraploid
and allohexaploid metabolic profiles. 2D NMR based compound identification showed
that the most variable metabolites were low molecular weight sugars, compounds that were more
abundant in seeds of allotetraploid wheats.
Conclusion: We discovered a correlation between ploidy and metabolomic profiles with higher concentrations
of soluble sugars in allotetraploid wheat.