Abstract:

Gliadin composition affects processing quality in bread wheat. CIMMYT and Australian germplasms have made a great contribution to improving yield and quality for Chinese spring wheat, so thirty-three spring wheat (Triticum aestivum L.) genotypes originated from CIMMYT, Australia and China were grown under four environments in 2003 and 2004. The flour sample was separated and quantified by reverse-phase high-performance liquid chromatography method in order to understand the composition of gliadin and the effects on quality properties in spring wheat. The results showed that significant variation in total gliadin and gliadin subgroups were observed among genotypes and environments. Within the subgroups, the α/β-type gliadins were generally presented the greatest amount (43.12%–50.87%), the γ-type gliadins content were the middle (32.71%–43.14%), and the ω-type gliadins content at lower levels (11.89%–21.58%). 1BL/1RS translocation affects the composition and the content of gliadin. High proportion of ω-type gliadins (17.44%–21.58%) was presented in 1B/1R translocation, however, no significant difference was observed on the amount of α/β-type gliadins between the 1B/1R translocation and the non-translocation genotypes. The amounts of total gliadin and the gliadin subgroups were significantly correlated with the protein content in flour of both the translocation and non-translocation lines, while weakly correlated with sedimentation volume, development time, stability time, extensibility and maximum resistance. It is likely that glutenin might play more important role in determining processing quality. In the translocation lines, ω, γ1 and γ-type gliadins had significantly positive correlation with sedimentation volume. Total gliadin, γ2 and γ-type gliadins had significantly positive correlation with dough development time, while ω and γ-gliadins had significantly negative correlation with dough extensibility.

Key words: Spring wheat, Reversed-phase high-performance liquid chromatography, Gliadin, Processing quality