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The pyrabactin resistance (PYR)/PYR-like (PYL)/regulatory component of ABA receptor (RCAR) proteins are the core components in ABA signaling pathway. A salt and cold induced ABA receptor gene VsPYL5 from common vetch was identified in the present study. Transgenic Arabidopsis overexpressing VsPYL5 had increased ABA sensitivity and higher levels of seed germination rate, survival rate, and the maximal photochemical efficiency of photosystem II (F v /F m) than the wild type (WT) under salinity conditions. Lower levels of the temperature that leads to 50% electrolyte leakage (TEL 50) and higher levels of survival rate after freezing treatment were observed in transgenic lines compared with WT. The results indicated that VsPYL5 regulated salt and cold tolerance positively. Lower levels of Na+ and Na+/K+ ratio but higher levels of K+ and AKT1 , GORK , KAT1 , HKT1 and KUP4 transcripts were observed in transgenic lines compared with WT under salinity conditions. The results indicated that the increased salt tolerance in transgenic lines was associated with the altered Na+ and K+ levels as a result of improved expression of genes involved in Na+ and K+ homeostasis. Antioxidant enzyme activities and their encoding gene transcripts, proline concentration and reactive oxygen species (ROS) levels were increased after treatment with salinity or cold, with lower levels in transgenic lines compared with WT. It is suggested that VsPYL5 -regulated salt and cold tolerance was associated with the increased proline level and antioxidant defense capacity for maintenance of ROS as a result of improved the relevant gene expression under salinity and cold conditions. Overexpression of VsPYL5 led to increased salt and cold tolerance through improved expression of genes involved in Na+ and K+ homeostasis and ROS homeostasis and increased antioxidant defense capacity • Transgenic Arabidopsis overexpressing VsPYL5 had increased ABA sensitivity and enhanced salt and cold tolerance. • Transgenic lines had lower levels of Na+ but higher levels of K+ under salinity conditions. • Maintenance of ROS were associated with cold and salt tolerance in transgenic lines. [ABSTRACT FROM AUTHOR]