Hydroponic and in vitro screening of wheat varieties for salt-tolerance

Abstract

Salt-tolerant wheat cultivars are essential for sustainable wheat production and global food security. The present study aimed to establish a reliable screening protocol as well as successfully isolated the potential salt-tolerant wheat varieties by discerning morpho-physiological parameters with multivariate analysis. Seventeen wheat varieties were evaluated at 0, 12, 15 and 18 dSm-1 salinity levels in a hydroponic culture system at the seedling stage. Moreover, in vitro callusing responses of four selected varieties were determined to clarify the salt tolerance capability at 0, 9, 12 and 15 dSm-1 salt treatments. The seedling growth of most wheat varieties was highly interrupted and reduced by the toxic effects of salinity, however, some varieties such as BARI Gom-32, BARI Gom-33, BARI Gom-31, BARI Gom-30, and BARI Gom-28 showed the lowest reduction under all salinity stress conditions. The total salt tolerance index (TSTI) showed that the cultivar BARI Gom-33 was the most salt-tolerant followed by BARI Gom-32 and BARI Gom-30 whereas BARI Gom-25 was identified as the most sensitive. These results were strongly supported by the principal component analysis (PCA) and Ward’s Methods Euclidean based clustering. In vitro results revealed that the lowest reduction of callus induction was recorded in BARI Gom-33 which might show the greatest tolerance to salinity by improving morpho-physiological characteristics against salt stress. Therefore, the identified genotypes might be employed as donor parents to develop salt-tolerant and high-yielding cultivars in the wheat breeding programme.