Plant roots play an important role in response to drought stress. Under this condition, plant roots can swiftly adjust to cope with water deficiency. We used anatomical, morphological and physiological analyses to investigate changes in the main growth to identify some mechanisms behind drought resistance among two cultivars, ancient wheat Saragolla and modern one, Svevo. Based on the root architecture traits (primary/lateral root and root hair) and all anatomical properties examined in this work, such as cross sectional area, stele area, aerenchyma area, metaxylem`s cross sectional area, we found that both cultivars were affected by drought stress. Nevertheless, the traits of Saragolla, did not diminish significantly, indicating that under drought stress it gives priority to the normal growth of the root system to maintain a superior biological performance, compared to Svevo. Confronting physiological parameters, “ancient” wheat showed notably a stronger antioxidant defense scavenging of ROS activities, more proline and a low ion leakage release after drought treatment. We concluded that Saragolla can have a better control obtaining the necessary water to maintain root growth, by augmenting regulation of biosynthetic enzymes and antioxidant or by reducing the damage caused by drought, thanks to a greater activity of ROS scavenging system.

To ascertain the origin of this better functionality of root system and sink-source arrangement inside the plant, further investigations are needed, considering hormonal cues and not only.