Physiological responses to exogenous ABA & SA in three michelia plants under temperature stress

Taking the 3-year-old saplings of Michelia polyneura C. Y. Wu，Michelia martinii and Michelia cavaleriei as material，a study was carried out on the effect of hardiness physiology characteristics such as Chl content， relative electric conductivity（ REC），soluble protein（ SP） content，MDA content and SOD activity with the spraying of exogenous abscisic acid and salicylic acid under low temperature stress. The results showed that SP content and SOD activity were improved to a certain degree by different concentration of ABA and SA，while the REC and MDA content were reduced. The chlorophyll degradation was reduced，so as to alleviate the damage degree of low temperature on the saplings. The effect with the treatment of 25 mg/L ABA was the most significant