为探讨外源水杨酸(SA)对高温胁迫下葡萄幼苗耐热性的影响,以二年生克瑞森无核葡萄扦插苗为试验材料,对清洗干净的葡萄叶片喷施浓度为150μmol/L的水杨酸(SA)溶液,之后置于45℃高温胁迫10,30,60,120,240,480min,以喷施蒸馏水后置于45℃高温胁迫10,30,60,120,240,480min为对照,研究外源水杨酸对可溶性蛋白含量、蛋白激酶活性、游离脯氨酸含量、电解质渗透率、丙二醛含量生理指标的影响。结果表明,高温胁迫下外源水杨酸(SA)增加可溶性蛋白和游离脯氨酸的含量;外源水杨酸诱导葡萄叶片蛋白激酶活性,促进蛋白磷酸化反应。可溶性蛋白含量变化与蛋白激酶活性的变化具有高度的一致性,即胁迫60min时可溶性蛋白含量增加到最大,蛋白激酶活性也同时增高到最大值;随着胁迫时间的延长(〉60min),外源水杨酸显著降低丙二醛的含量和相对电导率。外源水杨酸随着高温胁迫时间的延长(〉60min)可以显著增加葡萄幼苗叶片内可溶性蛋白和游离脯氨酸含量,降低丙二醛含量和电解质渗透率,显著降低细胞膜质过氧化伤害;增强蛋白激酶活性,促进蛋白磷酸化的反应,提高葡萄的耐热性。
Effect of exogenous salicylic acid(SA) on the heat tolerance in grape seedlings under high temperature stress was studied. Took two years old Vitis vinifera (Crinson) seedless grape cuttings as experimental material, took with 7-9 leaves of seedlings, cleaning and spring 150 μmol/L SA, then put them in 45 ℃ high temperature environment at different treatment time, such as 10 min, 30 min, 1 h, 2 h, 4 h and 8 h.And with the plant spaying distilled water, put them in 45 ℃ high temperature environment at different treatment time, such as 10 min, 30 min, 1 h, 2 h, 4 h and 8 h as control. The effects content, activity of the protein kinases, free soluble protein content and free proline of SA on soluble content, leakage protein rate ofelectrolyte, malondialdehyde(MDA) content were studied in Vitis vinifera (Crinson) seedlings leaves. The results showed that exogenous SA could enhance the contents of soluble protein and free proline, modulate the kinase activity, and promoted protein phosphorylation reaction. Changes of the soluble protein contentand the activity of protein kinase was consistent, the soluble protein content reached the peak when 1 h, meanwhile the activity of protein kinase reached the peak too. With the increase of high temperature stress (〉1 h), exogenous SA significantly decreased the leakage rate of electrolyte and malondialdehyde(MDA)content. In summary, exogenous SA could effectively increase the soluble protein content and free proline content, reduee the leakage rate of electrolyte and malondialdehyde(MDA) eontent significantly, decrease the ceil membrane lipid peroxidation injury, enhance the activity of protein kinase, and promote proteinphosphorylation reaction and improve the heat resistance of grape.