Physiological response of Chirita eburnea Hance seedling to chilling stress.

Objective Physiological response of Chirita eburnea Hance seedling to chilling stress was clarified to provide references for artificial cultivation. Method Young plants were treated under 5 ℃ for 12h, 24 h and 36 h respectively, and then recovered at 25℃ for 24 h and 48 h. The physiological indexes such as photochemical efficiency (Fv/Fm), leaf relative water content, electrolyte leakage, SOD activity and MDA content were measured. ResultThe results showed that Fv/Fm decreased along with the increasing of chilling time and could be recovered to normal level after chilling. Water content of leaves had a slight descending trend. The electrolyte leakage increased with the increasing of low temperature treating time and dropped again during the recovery. SOD activity and MDA content increased along with the treating time but could recover gradually. Conclusion The continuous low temperature treatment for 36 h at 5℃ caused a certain physiological stress but not critical damage, so the young plants of Chirita eburnean could gradually recover to normal growth.