LAUSR

MYB transcription factors play diverse roles in plant development and responses to abiotic stresses. However, the biological roles of MYB family members in rose (Rosa hybrida) are still unknown. Here, we reported the isolation and functional characterization of a novel rose RhMYB96 gene. RhMYB96 have a close relationship to Arabidopsis AtMYB96, including the presence of typical R2- and R3-domains at the N-terminal. Salt, dehydration, or ethylene signaling induce the expression of RhMYB96. RhMYB96 localized in the nucleus when expressed in Arabidopsis thaliana. We generated three independent transgenic Arabidopsis overexpressing RhMYB96 to explore the function of RhMYB96 in salt tolerance. Overexpression of RhMYB96 in Arabidopsis resulted in NaCl insensitivity during germination. Furthermore, RhMYB96-overexpressing seedlings under salt stress had longer primary root length and increased biomass. Specifically, the RhMYB96-overexpressed Arabidopsis plants displayed higher capability of scavenging the reactive oxygen levels H2O2 and O2− under salt stress. In addition, overexpressing RhMYB96 improved abscisic acid (ABA) sensitivity during germination. Expression of abiotic stresses and ABA-related genes was stronger in RhMYB96-overexpressing plants. These findings suggest that the RhMYB96 plays and regulates salt stress tolerance modulating an ABA-mediated pathway. Main Conclusion The novel rose RhMYB96 regulates salt stress through the modulation of an ABA-mediated pathway in Arabidopsis.