低温驯化对低温胁迫下茄子幼苗生理活性的影响

Effect of cold acclimation on physiological activity of eggplant seedlings under low temperature stress

【目的】为探明低温驯化与茄子幼苗抗寒性的关系.【方法】利用人工气候箱模拟低温条件,研究了低温驯化的茄子幼苗在低温胁迫、常温恢复和恢复之后再次胁迫时相对电导率、丙二醛(MDA)、渗透调节物质及抗氧化酶活性的变化.试验设置3个处理,25℃常温处理为对照;T_1:未经低温驯化;T_2:3d12℃低温驯化.【结果】3d12℃低温驯化期间,与CK相比各指标均升高,脯氨酸(Pro)含量与对照差异显著;5d5℃低温胁迫期间,与CK相比各指标均显著升高,T_2处理Pro、可溶性糖、可溶性蛋白含量、SOD、POD、CAT活性的升高幅度显著高于T_1处理,MDA含量和相对电导率的升高幅度显著低于T_1处理;25℃恢复3d,T_2处理各指标恢复速度显著高于T_1处理;恢复3d转移到低温胁迫处理1d,茄子幼苗相对电导率、MDA、Pro、可溶性糖、可溶性蛋白及抗氧化酶活性进一步升高,T_2处理升高幅度显著高于T_1处理,而MDA含量和相对电导率的升高幅度显著低于T_1处理.

[Objective] In order to discuss the relationship between cold acclimation and cold resistance of egg- plant seedlings. [Method] The experiment used artificial climate box to simulate low temperature condition and re search the change of the relative conductivity,malonaldehyde（MDA）, osmotic adjustment substance and antioxidant enzyme activities of eggplant seedling by cold acclimation under cold stress, recovery at normal temperature and af- ter recovery again cold stress. Three treatments were designed including CK（25 ℃ constant temperature treatment） ;T1 （without cold acclimation） and T2 （3 d after cold acclimation at 12 ℃ for 3 d ）. [Result] The result showed that all indicators increased during cold acclimation under 12 C for 3 d compared with the CK and proline content （Pro） was significantly greater than the control. During cold stress under 5 ℃ for 5 d the indicators all significantly increased and the Pro, solute sugar content, solute protein content SOD, POD, CAT activity were greater under Tz than T1, and MAD and relative conductivity were opposite. The recovery rate of tile indicators under T2 were signif- icantly higher than those under T1 after recovery at 25 C for 3 d, then transferring the recovered seedlings to low temperature for 1 d, the increase amplitude of Pro, soluble sugar, soluble protein and activity of antioxidant enzymes was significantly higher after cold acclimation than that without cold acclimation, and the increase amplitude of rela tive conductivity and MAD content was opposite.