Selecting Sesame Genotypes for Drought Tolerance Based on Some Physiochemical Traits

To assess drought tolerance, an understanding of sesame (Sesamum indicum L.) physiological properties is needed. The objective of this study was to determine the physiological responses of sesame accessions to drought stress. The experiment was conducted as a two-way factorial arranged in a randomized complete block design with three replications. All of the measured traits were accession-and drought-level-specific and discriminated the accessions into tolerant (Isfahan4, Rashtkhar, and Borazjan), moderately tolerant (Isfahan1, Ahvaz, Shiraz, Ardestan, and Kal), and sensitive (Markezi, Ultan, Khaf2, Khaf1, and Shahreza) groups.The results also showed that Khaf2 and Isfahan4 were the best accessions under normal and drought conditions, respectively. In addition, based on the correlation coefficient of the traits with seed yield, root proline and leaf carotenoid content were the superior markers with regard to drought tolerance in sesame. This study showed that accessions' differences in drought tolerance could be attributed to the ability of sesame plants to accumulate metabolites under drought conditions, and these metabolites could be a useful tool for depicting water-deficit tolerance of sesame genotypes, which could be useful to plant breeders for selecting and developing drought-tolerant cultivars.