Deciphering salt stress responses in Solanum pimpinellifolium through high‐throughput phenotyping.

SUMMARY: Soil salinity is a major environmental stressor affecting agricultural productivity worldwide. Understanding plant responses to salt stress is crucial for developing resilient crop varieties. Wild relatives of cultivated crops, such as wild tomato, Solanum pimpinellifolium, can serve as a useful resource to further expand the resilience potential of the cultivated germplasm, S. lycopersicum. In this study, we employed high‐throughput phenotyping in the greenhouse and field conditions to explore salt stress responses of a S. pimpinellifolium diversity panel. Our study revealed extensive phenotypic variations in response to salt stress, with traits such as transpiration rate, shoot mass, and ion accumulation showing significant correlations with plant performance. We found that while transpiration was a key determinant of plant performance in the greenhouse, shoot mass strongly correlated with yield under field conditions. Conversely, ion accumulation was the least influential factor under greenhouse conditions. Through a Genome Wide Association Study, we identified candidate genes not previously associated with salt stress, highlighting the power of high‐throughput phenotyping in uncovering novel aspects of plant stress responses. This study contributes to our understanding of salt stress tolerance in S. pimpinellifolium and lays the groundwork for further investigations into the genetic basis of these traits, ultimately informing breeding efforts for salinity tolerance in tomato and other crops. Significance Statement: While wild tomato relative, Solanum pimpinellifolium, has been previously used for agronomic improvements of cultivated tomato, its contributions in abiotic stress tolerance remain underexplored. Here, we developed a well genotyped diversity panel of S. pimpinellifolium and screened it under greenhouse and field conditions for salt stress tolerance. This study provides genetic resources, as well as initial identification of accessions and genetic loci underlying salt tolerance in wild tomato. [ABSTRACT FROM AUTHOR]