Impacts of SSIIa-A Null Allele on Durum Wheat Noodle Quality

A small increase in amylose content may impact end-product quality of wheat. The effect of elevated amylose content in durum wheat is not known. We surveyed 255 durum wheat accessions and found two genotypes that lacked the SGP-A1 protein. These genotypes were crossed to Mountrail, an adapted durum genotype, to create populations segregating for the SSIIa-Ab null allele. Our goal was to determine the influence of allelic variation at the SSIIa-A locus on semolina properties and end-product quality with noodles as a test product. Amylose content increased 3% and cooked noodle firmness increased 2.8 g-cm for the SSIIa-Ab class compared with the SSIIa-Aa class for the PI 330546 source, but no change in either trait was detected between classes for the IG 86304 source. The SSIIa-Ab class had a 10% reduction in flour swelling compared with the SSIIa-Aa class for both crosses. Grain protein and semolina yield did not differ between SSIIa-A classes. The relationship between flour swelling power and noodle firmness did not differ between SSIIa-A allelic classes within a cross. The different results for amylose content and noodle firmness between these sources may be because the two sources of the SSIIa-Ab null mutation contributed different linkages to the segregating populations. Results show that the SSIIa-Ab allele could be used to produce durum-based products that are slightly more firm in texture. However, the effect of the SSIIa-Ab allele may depend on the source.