Agro-morphological, physiological and biochemical performances of two new durum wheat cultivars under salt stress conditions

Soil salinization requires developing genetically salt-tolerant and high-yielding genotypes, especially in semi-arid and arid regions. In this study, two new Tunisian durum wheat cultivars, INRAT100 and Dhahbi, were tested for the first time in a semi-closed environment against salinity (0, 6 and 12 dS m-1). Dry weight of aerial and root parts, plant height, number of tillers per plant, spike and awn length, grain yield and its components, relative water content, relative membrane permeability, chlorophyll content, leaf chlorophyll fluorescence, i.e., initial fluorescence (F0) and the quantum yield of photosystem II (Fv/Fm), potassium (K+) and sodium (Na+) accumulation and the ratio K+/Na+ were assessed. Overall, most of growth and yield performance, physiological and biochemical attributes were affected by salinity. Notably, INRAT100 was characterized by a higher K+ content, K+/Na+ ion selectivity, relative water content and Fv/Fm, grain yield and lower membrane permeability than that of Dhahbi under saline conditions. However, Dhahbi exhibited higher spike and awn length and a number of spikelets per spike. These findings suggest that INRAT100 is more tolerant to salinity than Dhahbi and might be recommended to farmers of marginal environments.