Traceability of Sicilian Durum Wheat Landraces and Historical Varieties by High Molecular Weight Glutenins Footprint

Over the last new decade, there has been a strong interest in landraces and historical wheat varieties from farmers, manufacturers and consumers. They are agronomically and nutritionally interesting but the supply chain (from seed to end-product) is not solid and traceable. High molecular weight glutenins (HMW-GS) can act as markers to trace the varietal correspondence and to verify the genetic purity of the grain and consequently of the flours, marketed and labeled as mono-varietal. In the present work, HMW-GS of different durum wheat Sicilian landraces (Timilia, Russello, Perciasacchi) and one historical variety Margherito were analyzed. At first, specific protein profiles were assigned to each Sicilian landrace by SDS-PAGE and MALDI-TOF/MS analyses, thanks to the availability of pure seeds. Analysis of the protein profiles were then carried out from random samples of seed batches of the same landraces grown on a farm in South-East Sicily. The results highlighted the presence of different protein bands within the individual seed batches, which are reflected in complex profiles in the corresponding commercial flours labelled as mono-varietal. The bread wheat landrace Maiorca cultivated in the same farm was also found as a contaminant at different percentages in the durum wheat batches. The results of this study offer opportunities to improve the supply chain of the different Sicilian landraces or historical varieties cultivated, underlining the need for accurate controls from the field to the transformation process to be labelled as mono-varietal products.