From seed to bread: variation in quality in a set of old durum wheat cultivars

BACKGROUND: Old durum wheat varieties are being appreciated again because of their interesting genetic diversity and low fertilizer needs. RESULTS: The agronomic and bread-making performances of 14 old Italian durum wheat varieties grown under two low nitrogen (N) inputs (46 and 86 kg ha −1 ) were determined and the relationships among grain, semolina, dough and bread quality parameters were established. The old varieties yielded similarly to the check modern variety Svevo under both N levels. Increasing N fertilization from 46 to 86 kg ha −1 did not increase grain yield or the mg of N in the grain, although grain protein percentage increased as a result of a decrease in grain weight and an increase in gliadin content. Despite the resulting decrease in the gluten index, dough and bread quality improved at the higher N rate, highlighting the influential role of protein percentage and gliadin in bread quality. The genotypic variation in grain protein percentage among old varieties was more strongly associated with glutenin than with gliadin content. Variation in the gluten index was high (4–54); indeed, it was the most variable semolina parameter, and proved to contribute the most to variation in bread quality. This variation was independent of the glutenin alleles (HMW 20, 20*, 7, 13+16, 6+8) and was linked to the quality of the grain in terms of grain weight and the associated mg of N per grain. Remarkably, two old varieties, namely Calabria and Cappelli, were able to produce both a good yield and high-quality bread. CONCLUSION: Old Italian durum wheats continue to boast significant biodiversity and are worth exploring in low-input production systems. © 2019 Society of Chemical Industry.