Knockout of a novel salt responsive gene SlABIG1 enhance salinity tolerance in tomato

Salt stress can seriously reduce crop yield and quality, causing huge economic losses. Identification and functional of salt stress regulator could provide us a way to improve plants tolerance to salt stress. The HD-ZIP II subfamily is plant-specific transcription factors, plays a crucial role in plant development and abiotic stress. In this study, we analyzed the expression profiling of all HD-ZIP II members response to salt, drought, high temperature and cold stress using publicly accessible transcriptome data, and identified a novel salt stress negative regulator SlABIG1 in tomato. Under salt stress, knockout of SlABIG1 significantly improved the salt tolerance of tomato, with higher chlorophyll content and photosynthetic capacity, root dry weight and proline; decreased the accumulation of ROS, MDA and Na+. Collectively, our results revealed that SlABIG1 plays a key role in tomato tolerance to salinity stress and provide a candidate novel gene to create salt-tolerant tomato varieties in future.