Drought and Heat Stress Impacts on Phenolic Acids Accumulation in Durum Wheat Cultivars

Droughts and high temperatures are the main abiotic constraints hampering durum wheatproduction. This study investigated the accumulation of phenolic acids (PAs) in the wholemeal flourof six durum wheat cultivars under drought and heat stress. Phenolic acids were extracted fromwholemeals and analysed through HPLC-DAD analysis. Ferulic acid was the most represented PA,varying from 390.1 to 785.6 g/g dry matter across all cultivars and growth conditions, followed bysinapic acids, p-coumaric, vanillic, syringic, and p-hydroxybenzoic acids. Among the cultivars, Cirnohad the highest PAs content, especially under severe drought conditions. Heat stress enhanced theaccumulation of minor individual PAs, whereas severe drought increased ferulic acid and total PAs.Broad-sense heritability was low (0.23) for p-coumaric acid but >0.69 for all other components. Positivecorrelations occurred between PA content and grain morphology and between test weight andgrain yield. Durum wheat genotypes with good yields and high accumulation of PAs across differentgrowing conditions could be significant for durum wheat resilience and health-promoting value.