Abstract

In order to understand the effect of water stress and try to select resistant durum wheat genotypes, the present study was conducted on four leaf stage seedlings (parents and F1 hybrids) which were submitted, under semi-controlled conditions, at different stress levels 40, 30, 20, 10 and 6.5% of field capacity (F.C.). The parameters studied are the proline dosage, the stomatal resistance measurement and the heterosis calculation. The results show positive correlations between stomatal resistance and proline accumulation, on the one hand, and the different levels of water stress applied, on the other hand. Under severe water stress, 6.5% F.C., the proline content is in the majority of genotypes, 96 to 246 times the value recorded under basic stress, 40% F.C. With the exception of the hybrid Dek x Hau, it is in the order of 723. The most significant concentrations are recorded in F1 hybrids while parents take intermediate levels. Stomatal resistance increases with the degree of stress and stress is no different really than stress 10% F.C. Hybrid vigor is manifested clearly in the F1. The behavior of genotypes is not associated with an isolated physiological behavior of the variety, but a strategy that includes one or more mechanisms of tolerance and (or) avoidance of water stress