Gluten protein response to heat and drought stress in durum wheat as measured by reverse phase-High performance liquid chromatography

Drought and heat stress during the grain-filling period has been found to significantly alter gluten protein composition in wheat. Reversed phase-high performance liquid chromatography was used to assess the effect of environmental stress conditions (moderate and severe drought and heat stress) on variation of gluten proteins in six durum wheat cultivars with the same high molecular weight (HMW) and low molecular weight (LMW) glutenin subunit composition. The gliadin fractions were highly affected by genotype, and the LMW glutenins not at all. The LMW glutenins and gamma-gliadin were significantly reduced by all stress treatments. The gamma-gliadins were highly significantly correlated with dough strength and other alveograph characteristics, and mixograph development time under all growing conditions. All stress treatments caused an increase in alpha-gliadins. HMW glutenins were significantly and negatively correlated with dough strength under all treatments except severe heat stress conditions. The gamma-gliadins showed positive significant correlations with dough strength, alveograph tenacity and mixograph peak time for most treatments. The omega- and alpha-gliadins had a negative influence on alveograph characteristics, irrespective of the conditions the wheat was grown under.