The present study investigates the effects of exogenous salicylic acid (SA) on the expression of Vitis vinifera C-repeat binding factor 4 (VvCBF4) gene under low-temperature conditions in an Iranian Vitis viniferea L. 'Sultanina'. The experiment was conducted as a factorial experiment based on a completely randomized design with four replications. 100 μmol/L SA (0, 1, 6 and 12 h before applying cold stress) in temperatures of 1 ± 0.5 °C (for 1, 3, 6 and 12 h) and 22 °C (as control) were applied. The highest expression was observed in plants treated 6 h before sampling. By increasing the duration of low temperature, the expression of VvCBF4 increased. Increasing the duration of cold stress to 6 h in 1 °C increased the expression of VvCBF4 to 24.3 fold. Exogenous application of SA and cold stress treatments increased the expression of VvCBF4. In conclusion, exogenous application of SA in cold stress, increased the expression of VvCBF4 depending on treating time before cold stress. The highest VvCBF4 expression was observed in plants treated 6 h before sampling and increasing the time decreased the expression. By increasing the expression of VvCBF4 the tolerance of plant to cold stress increased.
Keywords: Cold stress; Salicylic acid; Vitis viniferea; VvCBF4; qRT-PCR.