Abstract:
(CoUpe ofHorticulture，China Agr／cuhura／ ，~／j／ng 100094，Ch／na)
Thennotolerance and antioxidation induced by heat acclimation or exogenous SA treatment were studied in grape(Vitis vinifera CV．Jingxiu)seedlings． e results showed that thermotolerance of grape~ mngs was enhanced by heat acclimation or exogenous SA． en seedlings were acclimated under 38℃ for lh．the content of free SA in grape leaves rose from 3．086 gg‘g FM to 19．081 gg。g FM ．then declined to 8．269 gg。g FM after 6 h of heat cclimation．Activities of antioxidant enzymes including superoxide dismutase(SOD)，per0 一
dase(POD)，glutathione reductase(GR)and ascorbic pemxidase(APX)were elevated，but the activtity of catalase(CAT)Was decreased． e content of hydrogen peroxide(H202)in grape leaves were drastically elevated at lh．then rapidly declined ． e results suggested that SA ma y take part in heat acclimation that induced thermo tolerance through induction activity of antioxidative enzymes， SA treatment an d heat acclima tion showed common
mechanism of inducing theromotolerance of plants．

Key words: vinifera, Salicyhc acid, Heat acclimation, Thermotoleranee, Antioxidant nzyme