Etude de tolérance au stress hydrique chez quelque variété de blé dur (Triticun durum Dest)

Abstract

Actually,water deficit constitutes the main abiotic stress considerably limiting the productivity of durum wheat (Triticum durum Desf.) in Algeria. The development of new wheat varieties adapted to climate change, particularly tolerant to water stress, has become a strategic issue for agricultural production in the coming decades. This work has two main parts. First, we studied in semi-controlled conditions the response variability of six genotypes of durum wheat (Triticum durum Desf.) subjected to three levels of water regime (100%, 70% and 40% of the retention capacity). The plant material used is originally introduced and conducted in randomized blocks with four repetitions. Morphophysiological traits were used to evaluate the tolerance of genotypes to water stress such as: germination and growth parameters. The second part of our work consisted of evaluating the agronomic performances of our genotypes in greenhouses, based on pheno-morphological and agronomic characters. For the first study, the results obtained show that the germination rate was relatively high, in addition to the depressive effect on the height and growth of the plant, in particular; the number of roots, the leaf area, and also the height of the plant, which are also observed in stressed plants compared to controls. These effects are all the more important as the intensity and duration of stress are high. For the greenhouse study, the results obtained show that the water deficit caused a drop in the height of the stem, the length of the neck of the ear, and also a reduction in the length of the last node, in addition to a decrease in both the number of seeds per ear and the weight of thousand seeds. The study showed that all varieties have the same response to water stress, but to varying degrees.