Yielding ability, yield stability, and quality of exotic durum wheat germplasm in Sicily

A set of 20 accessions of durum wheat (Triticum turgidum L., durum group), which mostly included exotic landraces from various Mediterranean countries, and four Italian improved varieties were evaluated for grain yield in five environments and for quality traits in two environments of Sicily. Glutenin composition was also assessed electrophoretically on six seeds per entry. The cultivars differed (P less than or equal to 0.01) for yield, protein content and sodium dodecyl sulphate (SDS-sed) sedimentation volume, in the presence of significant (P less than or equal to 0.001) genotype-environment interaction effects. These effects were large for yield and moderately large for protein content relative to genotype main effects following estimation of variance components. Most exotic cultivars yielded comparably with, and some of them showed greater stability than, the best yielding Italian variety 'Simeto'. Some exotic cultivars combined outstanding yield, protein content and SDS-sedimentation values and represent therefore extremely valuable germplasm sources to broaden the local genetic base. The glutenin composition LMW-2 and HMW 7 + 8 was positively associated with gluten quality. Six entries showed heterogeneous electrophoretic patterns, suggesting the presence of different genotypes within the cultivar.