Screening of Triticum turgidum genotypes for tolerance to drought stress.

Drought is one of the major abiotic stresses leading to reduced yields and economic losses. Effective germplasm screening for drought tolerance particularly under managed water-deficit conditions is an effective way of selecting materials for advanced breeding programs. Here, 37 Triticum turgidum genotypes, including landraces, ancient and modern genotypes, along with 2 tritordeum cultivars, were subjected to water-deficit stress through the application of 10% (w/v) PEG 6000 and to re-watering treatment in controlled environment, and at the end of each treatment, several physiological and morphological traits were investigated. Our results revealed large variation in shoot and root fresh weight, proline, chlorophyll, and MDA concentration, and also in root morphological traits across the 37 genotypes. The hierarchical clustering of the physiological and morphological traits led to the identification of tolerant and sensitive genotypes to water-deficit stress and also reveals those genotypes characterized by deep-rooting and shallow-rooting systems. By integrating both datasets, three outstanding genotypes, namely Karim, Svems 20, and Svems 18 were identified as the most tolerant genotypes with deep-rooting system. On the other hand, Iride and Bulel tritordeum, were introduced as the most sensitive genotypes with shallow-rooting system.