Effects of Exogenous Salicylic Acid on Cold Resistance of Blueberry Flower Buds during Dormancy
In this study,effects of different concentrations of exogenous salicylic acid(SA)on physio-logical and biochemical characteristics of blueberry flower buds during dormancy were studied using 6-year-old blueberry'Northland'as experimental material.The results showed that the contents of osmotic regulation substances,and enzymatic and non-enzymatic reaction systems in blueberry flower buds increased obviously at first and then decreased slowly with the extension of dormancy.Spraying exogenous SA at appropriate concen-tration could alleviate the damage of low temperature on blueberry flower buds during dormancy by increasing the contents of soluble protein,soluble sugar and proline,reducing MDA content,promoting activities of an-tioxidant protective enzymes such as SOD and POD,and up-regulating the ascorbic acid and glutathione(AsA-GSH)circulation system.In conclusion,exogenous SA was involved in the physiological response of blueberry plants to low temperature stress in a concentration-dependent manner;1.0 mmol·L-1 was the opti-mum concentration of SA for alleviating the effects,and damages were aggravated when the concentration was up to 10.0 mmol·L-1.