Effects of Salicylic Acid on Winter Freezing Tolerance in Grapevine (Vitis vinifera cv. Shahani)

The present study was conducted to evaluate the effects of salicylic acid on freezing tolerance in Grapevine (Vitis vinifera cv. Shahani) as a factorial based on randomized complete block design with three replications in 94 and 95 years. Factors in the first year included SA (0, 0.5 and 1 mM) foliar application at the time of the veraision, harvest, one month after harvest and three times. Freezing treatments were 4 (control), -15, 18- and 21- °C on cuttings that collected in January and March. Second year experiment based on the results of the first year and spraying with concentrations of 0, 0.5 and 1.5 mM in the stage of one month after harvest and freezing at 4, -17, -19 and -21 °C on the cutting that collected in January and March. Based on the results of this study, the use of the SA 0.5 and 1 mM in the first year and 0.5 and 1.5 mM in the second experiment reduced the peroxidation of membrane lipids and thus reduced the level of ionic and phenolic leakage and malondialdehyde after freezing stress and increased carbohydrate solution, proline and phenolic compounds at both sampling times in January and March. So it seems that SA could decrease effects of low temperatures and damage to cell lipids. Also, the results showed which deduction the temperature to -21°C reduced the vegetative parameters of cuttings and it seems that SA could improve the cold stress damages in cuttings by increasing some of the biochemical parameters.