Abstract: Reserve starch, the main component of durum wheat semolina, is constituted by two glucan homopolymers (amylose and amylopectin) that differ in their chemical structure. Amylose is mainly a linear structure formed of α-1,4 linked glucose units, with a lower polymerization degree, whereas amylopectin is a highly branched structure of α-1,4 chains linked by α-1,6 bonds. Variation of the amylose/amylopectin ratio has a profound effect on the starch properties which may impact wheat technological and nutritional characteristics and their possible use in the food and non-food sector. Therefore, some breeding programs were focused on the production of high (HA) and low amylose (LA) genotypes using transgenic and conventional strategies. A great interest was aroused by new genotypes enriched in amylose for their beneficial effects for human health in the prevention of non-communicable diseases. Differently the low-amylose genotypes find applications in different industrial sectors (i.e. frozen and baby foods; starch-based sweeteners and industrial alcohol) for their unique properties. In this work a set of genotypes, with a range of amylose from 14.9 to 57.8%, derived from the durum wheat cv. Svevo was characterized at biochemical and rheological level and used for the production of pasta. A negative correlation was observed between amylose content and semolina swelling power, starch peak viscosity and pasta stickiness. A worsening of the firmness was observed in the low amylose pasta compared to the control (cv. Svevo), whereas no difference was highlighted in the high amylose samples. The resistant starch was higher in the HA pasta compared to the control and LA pasta. Noteworthy, the extent of starch digestion was reduced in the high amylose pasta while the low amylose genotypes offered a higher starch digestion, suggesting other possible applications.

A bread wheat line (N11) and a disomic 2D(2R) substitution triticale line have been crossed and backrossed four times. At each step electrophoretic selection for the seeds that possessed, simultaneously, the complete set of high molecular weight glutenin subunits of N11 and the two high molecular weight secalins of rye, present in the 2D(2R) line, was carried out. Molecular cytogenetic analyses of the BC4F5 generation have revealed that the selection carried out had produced a disomic addition line (2n=44). The pair of additional chromosomes consisted of the long arm of chromosome 1R (1RL) from rye fused with the satellite body of the wheat chromosome 6B. Rheological analyses revealed that the dough obtained by the new addition line had higher quality characteristics when compared with the two parents. The role of the two additional high molecular weight secalins, present in the disomic addition line, in influencing improved dough characteristics is discussed.

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 having, as overall objective, the preservation of biodiversity and the containment of genetic erosion. In recent years, products derived from an-cient grains are perceived to be healthier and more sustainable by consumer, especially in Italy, with consequent higher market prices. Ancient tetraploid wheat varieties registered in the national reg-ister of conservation varieties are 28, 24 of which are Sicilian. They are supposed to have a wide genetic variability compared to modern ones, making them vulnerable of fraud because they are difficult to trace. It is therefore important to have tools able to discriminate the autochthonous Si-cilian varieties. This can be done by gluten proteins composition, which also gives information on the technological properties of derived products. Fifty-one accessions belonging to 22 ancient va-rieties of Sicilian tetraploid (mostly durum) wheat were analyzed. Although a wide intra-accession and intra-varietal variability was 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 about the transparency of the entire supply chain.