Résumé:
Generally,drought is the most significant and limiting factor for crops in general and for soft wheat in particular, especially in semi-arid zones. The present study aims to study the mechanism of tolerance to abiotic stress in some varieties of wheat. To do this, a global strategy was followed, combining phenotypic and genotypic studies by integrating different physiological, morphological and agronomic characteristics. The study made it possible to provide an overall view of the behavior of 5 varieties of common wheat (Triticum aestivum L.) with respect to water deficit and to distinguish the varieties least affected by this constraint. The plant material consisted of two local varieties ARZ and Ain Abid and three newly introduced varieties from Italy (Anforeta, Anafo, Palésio),
Conducted in randomized blocks with five repetitions and subjected to different water stress treatments with three levels of irrigation , control T1 (100% CR), moderate stress T2 (70% CR) and severe stress T3 (40% CR), by carrying out a comparison of some tolerance mechanisms. The results obtained show that the germination rate was relatively high, with a depressing effect on the growth of the plant, in particular; the number of roots, the height of the plant and the aerial Biomass, whichare thus observed in stressed plants, compared to controls. For the greenhouse study, the effect of water stress is very significant on almost all of the morphological and agronomic traits analyzed. In conclusion, the study showed that water stress provokes the same response mechanisms in the genotypes studied but to different degrees, and are all the more important, as the intensity and duration of the stress are high.
