低温胁迫对观光木幼苗离体叶片生理特性的影响

摘要

以一年生盆栽观光木幼苗为材料,研究了低温胁迫(12、8、4、0℃)下幼苗叶片有关的生理生化指标变化及其与抗寒性的关系.结果表明,低温对观光木叶片的相对电导率、丙二醛含量、超氧化物歧化酶活性、脯氨酸和可溶性糖含量的影响均达到极显著水平.随温度的降低,观光木叶片的相对电导率、脯氨酸和可溶性糖含量不断升高;丙二醛含量呈先上升后略下降的变化趋势,但总体高于对照(25℃)的含量；超氧化物歧化酶活性也不断升高,且在0℃时达到最大值,为对照的4.43倍.相关性分析结果显示,低温与相对电导率、可溶性糖含量的相关系数均达0.894以上,呈显著的负相关,但低温与丙二醛含量、超氧化物歧化酶活性、脯氨酸含量的相关性不显著.%The relationship between cold-resistance and physiological changes of seedlings leaves under cold stress(12, 8, 4, 0℃) was studied using one-year-old pot Tsoongiodendron odorum as material. The results showed that the effects of low-temperature on relative electric conductivity (REC), malondialdehyde (MDA) content, superoxide dismutase (SOD) activity, proline (Pro) and soluble sugar content in leaves of T. Odorum were extremely significant. With the decreasing of temperature, the REC, Pro and soluble sugar content increased obviously; the MDA content increased firstly and then reduced slightly, but generally was higher than that of control (25 ℃); the activity of SOD increased continuously and reached the peak (4.43 times of that of control) at 0 ℃. Correlation analysis showed that the correlation between low— temperature and REC, soluble sugar content was significantly negative as the correlation efficient was above 0.894. However, the relevance between low-temperature and MDA content, SOD activity, Pro content was not significant.