Multi-dimensional evaluation of responses to salt stress of <i>Berbet</i> introgression lines of wheat (<i>Triticum aestivum</i> L.)

Abstract Soil and irrigation water salinity represent major abiotic stressors limiting global cereal production. This study aimed to assess the variability in salt tolerance among 78 Berbet introgression lines ( Berbet-ILs ) of wheat and four commercial cultivars at both seedling (controlled laboratory) and adult plant (field) stages. Twelve-day-old seedlings were evaluated for morpho-physiological traits, including germination percentage, root/shoot length, fresh/dry biomass and seedling vigour indices (I and II). Salinity significantly affected all seedling traits ( P ≤ 0.01), including germination percentage. At the adult stage, plants were grown in fields irrigated with saline canal water (electrical conductivity [EC] = 3.8–4.2 dS · m⁻ 1 ) and non-saline tubewell water (EC = 0.3–0.4 dS · m⁻ 1 ). They were assessed for plant height, spikelets per spike, grains per spike, 1000-grain weight, grain yield, harvest index, phenological traits (days to flowering and maturity) and total leaf chlorophyll measured as Soil Plant Analysis Development (SPAD) values. Analysis of variance revealed significant effects of salinity on all parameters ( P ≤ 0.01), except chlorophyll content at 20 days after anthesis and days to maturity. Salt Tolerance Index (STI) was calculated for each trait, and Pearson’s correlation analysis was performed on STI values. Hierarchical cluster analysis, based on the mean membership function value, identified L1, L6, L10, L45, L47, L72, L76, L77 and L79 as the most salt-tolerant Berbet-ILs , comparable to the commercial cultivars KRL 210 and PBW 803. Further physiological and biochemical characterization is recommended to understand the mechanisms driving salt tolerance. These findings can aid in developing high-yielding, salt-tolerant wheat varieties suited for saline-prone regions.