Abstract

Tomato (Solanum lycopersicum) is one of the most important vegetable crops worldwide; however, environmental stressors severely restrict tomato growth and yield. Therefore, it is of great interest to discover novel regulators to improve tomato growth and environmental stress adaptions. Here, we applied a comprehensive bioinformatics approach to identify putative tomatoC-TERMINALLY ENCODED PEPTIDE(CEP) genes and to explore their potential physiological function in tomato root development and abiotic stress responses. A total of 17 tomatoCEPgenes were identified and grouped into two subgroups based on the similarity of CEP motifs. The public RNA-Seq data revealed that tomatoCEPgenes displayed a diverse expression pattern in tomato tissues. Additionally,CEPgenes expression was differentially regulated by nitrate or ammonium status in roots and shoots, respectively. The differences in expression levels ofCEPgenes induced by nitrogen indicate a potential involvement ofCEPs in tomato nitrogen acquisition. The synthetic CEP peptides promoted tomato primary root growth, which requires nitric oxide (NO) and calcium signaling. Furthermore, we also revealed that CEP peptides improved tomato root resistance to salinity. Overall, our work will contribute to provide novel genetic breeding strategies for tomato cultivation under adverse environments.Keywords:Solanum lycopersicum;CEP peptide;root growth;nitric oxide;nitrogen;salinity