SlARF4 Under Expression Improves Tolerance to Salinity in Tomato (Solanum lycopersicum)

Abstract

Understanding physiological and molecular basis of plant response and tolerance to environmental constraints and abiotic stresses is important to improve plant survival, crop yield and quality. Auxin controls many aspects of plant growth and development. This phytohormone acts on the transcriptional regulation of target genes, mainly through Auxin Response Factors (ARF). However, its role in stress responses remains so far poorly studied. The current study provide clues supporting the involvement of an auxin response factor; ARF4 in tomato tolerance to salt stress. Using a reverse genetic approach, we found that the down-regulation of an auxin response factor; SlARF4 improves tomato tolerance to salt by promoting root development and density and maintaining good development and high chlorophyll content under salt stress conditions. Our results bring new elements on auxin involvement in plant stress responses and underline the role of ARF4 in salt tolerance. These provide
new insights into tomato selection and breeding for environmental stress-tolerant.