Yield Related Traits and Tolerance Indices to Screen Salinity Tolerant Genotypes in Cultivated and Wild Barley
Salinity is one of the major abiotic factors limiting crop production worldwide. To assess salinity stress tolerance of wild (Hordeum vulgare ssp. spontaneum L.) and cultivated (H. vulgare ssp. vulgare L.) barley genotypes, a two-year field experiment was carried out. Plant height, days to heading, days to anthesis, days to maturity, spike length, grain yield, and yield components were evaluated under normal and salinity stress conditions. The stress stability index (SSI), tolerance index (TOL), yield index (YI), stress tolerance index (STI), geometric mean productivity (GMP), mean productivity (MP), and yield stability index (YSI) were the tolerance indices used in this study. The results showed significant effects of salinity stress and genotype on the measured and calculated variables. The wild genotypes were less affected by salinity stress than the cultivated ones and thus were far superior for the stability indices for yield (STI and YSI). On the other hand, barley cultivars were superior for yield obtained under normal (Yp) and saline (Ys) conditions, MP, GMP, and TOL. A strong relationship was found between grain yield and three indices (STI, YI, and YSI). Ultimately, cluster and principal component analyses suggested that the implementation of STI and YSI in the screening of the wild genotypes for salinity tolerance results in a more robust determination of the most salinity tolerant genotypes.