Identifying reliable traits for screening tomato genotypes under salt stress conditions

Salinity is considered as complex stress and plants show different reactions to this stress based on their genetic structure. Therefore, it is possible to achieve the salinity-tolerant genotype in plants through creating changes in the genetic structure and breeding activities. Tomato is in the group of plants sensitive to salinity stress. Distinct studies have been explained different indicators for tolerance to salt stress in tomato. Identifying a reliable indicator in the early stages of plant growth under salt stress is necessary to evaluate a large number of samples in plant breeding projects. Based on this, in the current project, 10 tomato genotypes were evaluated under salt stress in the form of a randomized complete block design with three replications. The results of variance analysis showed a statistically significant difference between genotypes for the stress tolerance index in the traits of root dry weight (RDW), root fresh weight (RFW), leaf dry weight (LDW), leaf fresh weight (LFW), stem fresh weight (SFW), total dry weight (TDW) and total fresh weight (TFW). The results of cluster analysis and GGEbiplot analysis classified the genotypes into four groups. Based on the results of multiple regression analysis, the index of stress tolerance with total dry weight (STI-TDW) and total fresh weight (STI-TFW) was recognized as a suitable index for evaluating tolerance to salt stress in tomato genotypes. It seems that these index can be used for the screening of tomato germplasms under salt stress for plant breeding projects.