香木莲对短时低温胁迫处理的生理生态响应

Ecophysiological Response of Manglietia aromatica to Short-term Low Temperature Treatment

通过测定木兰科植物香木莲在人为短时低温处理下的一些生理生化指标的变化情况,可以分析香木莲苗木的抗性生理情况,以期对香木莲的抗寒性进行评价。实验结果表明,香木莲的叶片在经短时低温处理后,其脯氨酸含量、丙二醛含量及相对电导率均表现为不同程度的上升。而叶片的叶绿素荧光指数的变化则表现为随处理时间的延长,叶片的原初荧光(Fo)上升,其光化学效率(Fv/Fm)及可变荧光/原初荧光比率(Fv/Fo)则表现为随处理时间的延长而降低。这表明,短时低温处理对叶片的叶绿体光系统的潜在活性及量子传递效率造成了一定的影响,结合生理生化指标的变化,可以部分解释香木莲抗寒机制。

The variation of the physiological indices at low temperature of the Manglietia aromatica leaves have been measured in this experiment. The results indicate that the concentration of the free Proline. the malondialdelyole（MDA）, soluble sugar and the relative dectrical conductivity in leaves increased with the extended time of treatment. Among the chlorophyll fluorescence Parameters（Fv/Fm） and the variable fluorescence/initial fluorescence ratio（Fv/Fo）decreased, which could be explained by the influence of the low temperature on photosystem Ⅱ （PSⅡ）. In leaves of Manglietia aromatica, the maximum quantum efficiency of PSⅡ primary photochemistry （ Fv/Fm）was significantly affected after 4h exposure to the low temperature of 2℃. The results could be used as the criterion for evaluation of the mechanism of winter resistance of Manglietia aromatica.