Comparative Responses of Algerian Tetraploid Wheat Cultivars to Salinity at the Seedling Stage

Abstract

Salinity is one of the most abiotic stresses restricting wheat growth and productivity in arid and semi-arid regions. This study was carried out to examine the effect of salt stress induced by sodium chloride (NaCl) at different concentration levels (0, 50, 100 and 150 mM) on seed germination rate, root length, roots number, coleoptile length, root and shoot fresh weights of eleven durum wheat varieties. The results revealed significant differences among the genotypes for all the measured parameters. The increase in NaCl concentrations showed concomitant decrease in all morphological attributes, but varied depending on cultivars and levels of salinity. Seed germination rate and root length demonstrated a linear response to NaCl treatment, while significant linear and quadratic regression on salinity for roots number, coleoptile length, root and shoot fresh weights were observed. The cluster analysis based on Ward’s method sequestrated the studied genotypes into three clusters. Seed germination rate and root length showed the lowest difference among the groups; and the remaining traits: roots number, coleoptile length, root and shoot fresh weights were the most indicative of salt-tolerance. Waha, Megress and GTA dur were the most tolerant genotypes that could be used as donors of choice in wheat breeding programs targeting the improvement of salinity tolerance during the seedling stage.