Characterization of Triticum turgidum sspp. durum, turanicum, and polonicum grown in Central Italy in relation to technological and nutritional aspects

Sulphur-mediated iron homeostasis in four tetraploid wheats (Triticum turgidum L.)

Sulphur (S) deficiency is known to hinder iron (Fe) uptake and distribution in wheat, mainly by reducing phytosiderophores (PS) synthesis and release. This study investigated the impact of S supply on Fe accumulation in four tetraploid wheat genotypes with different genetic backgrounds: a modern genotype, Svevo (Triticum turgidum subsp. durum), two ancient Khorasan wheats, Turanicum_21 and Etrusco (T. turgidum subsp. turanicum) and an ancient Polish wheat, Polonicum_2 (T. turgidum subsp. polonicum). Plants were grown hydroponically for 20 days under adequate (S = 1.2 mM) or limiting (L = 0.06 mM) sulfate levels, while receiving sufficient Fe (80 μM). Most genotypes exhibited reduced Fe accumulation under low S conditions, as expected. However, Polonicum_2 showed a unique response, accumulating significantly more Fe in both shoots and roots. This increased Fe accumulation was associated with a higher rate of PS release and upregulation of both TdYSL15 and TdIRO2 in roots of Polonicum_2, suggesting altered regulation of Fe deficiency responses. However, the expression pattern of TdIDEF1 was not correlated with TdYSL15 expression in this plant, suggesting the involvement of additional regulatory pathways beyond Fe supply. Finally, there was a strong correlation between O-acetylserine(thiol)lyase activity in shoot tissues and PS release rate across all genotypes. There is increased interest in Khorasan and Polish wheats as alternative crops for marginal areas, hence, these findings are noteworthy from a biofortification perspective and could potentially lead to innovations in agriculture that benefit food security.

Identification of Genomic Regions Conferring Enhanced Zn and Fe Concentration in Wheat Varieties and Introgression Lines Derived from Wild Relatives

Wild and cultivated relatives of wheat are an important source of genetic factors for improving the mineral composition of wheat. In this work, a wheat panel consisting of modern bread wheat varieties, landraces, and introgression lines with genetic material of the wheat species Triticum timopheevii, T. durum, T. dicoccum, and T. dicoccoides and the synthetic line T. kiharae was used to identify loci associated with the grain zinc (GZnC) and iron (GFeC) content. Using a BLINK model, we identified 31 and 73 marker-trait associations (MTAs) for GZnC and GFeC, respectively, of which 19 were novel. Twelve MTAs distributed on chromosomes 1B, 2A, 2B, 5A, and 5B were significantly associated with GZnC, five MTAs on 2A, 2B, and 5D chromosomes were significantly associated with GFeC, and two SNPs located on 2A and 2B were related to the grain concentration of both trace elements. Meanwhile, most of these MTAs were inherited from At and G genomes of T. timopheevii and T. kiharae and positively affected GZnC and GFeC. Eight genes related to iron or zinc transporters, representing diverse gene families, were proposed as the best candidates. Our findings provide an understanding of the genetic basis of grain Zn and Fe accumulation in species of the Timopheevi group and could help in selecting new genotypes containing valuable loci.

Characterization among and within Sicilian Tetraploid Wheat Landraces by Gluten Protein Analysis for Traceability Purposes

The criteria of "Distinctness, Uniformity and Stability" as well as a high "overall quality index" are used to register the Italian modern varieties to the national register. Differently, local conservation varieties can be certified under different EU Directives that facilitate, as an overall objective, the preservation of biodiversity and the containment of genetic erosion. In recent years, products derived from ancient grains are perceived to be healthier and more sustainable by consumers, especially in Italy, with consequent higher market prices. The ancient tetraploid wheat varieties registered in the national register of conservation varieties amount to 28, 24 of which are Sicilian. They are supposed to have wide genetic variability compared to modern ones, making them vulnerable to fraud because they are difficult to trace. It is therefore important to have tools able to discriminate between autochthonous Sicilian varieties. This can be completed by gluten proteins composition, which also provides information on the technological properties of derived products. Fifty-one accessions belonging to twenty-two ancient varieties of Sicilian tetraploid (mostly durum) wheat were analyzed. Although wide intra-accession and intra-varietal variability measurements were assessed, the gliadin pattern of bulks of seeds belonging to each variety was discriminatory. Moreover, differences in technological attitudes were found between landraces. This paves the way to use gluten protein patterns for traceability, allowing local farmers and producers to valorize their products and assure consumers regarding the transparency of the entire supply chain.