干旱胁迫对刺五加生长以及光合生理参数的影响

Effect of Drought Stress on Growth and Photosynthetic Physiological Parameters of Acanthopanax senticosus

目的:研究不同干旱胁迫条件对刺五加生长及光合生理参数的共同影响,可为规范化种植和合理开发利用刺五加提供理论依据。方法:该研究使用三年生刺五加为实验样本,通过测定株高、叶片数、叶面积等生长参数以及光合生理参数,研究不同水分条件对刺五加生长及光合作用的影响规律。结果:株高、叶片数在干旱胁迫条件下显著低于空白组,叶面积在干旱胁迫条件高于空白组。净光合速率、气孔导度、蒸腾速率在空白组与中度干旱胁迫组中无显著性差异,这些参数在重度干旱胁迫组中显著降低,而胞间二氧化碳浓度则随着干旱胁迫程度的加深而增加。随着处理时间的进行,初始荧光在重度干旱胁迫组高于空白组,中度干旱胁迫组则低于空白组;最大荧光在重度干旱胁迫组显著低于空白组;潜在光化学效率和最大光化学效率则在中度干旱胁迫组显著升高。结论:干旱胁迫条件可显著抑制刺五加的生长,重度干旱条件可显著抑制刺五加叶片光合作用,这种作用与其调节气孔大小有关,而与光反应中心的活性无关。

Objective: To study the effects of different drought conditions on the growth and photosynthetic physiological parameters of Acanthopanax senticosus,in order to provide the theoretical basis for standardized planting and rational development and utilization of A. senticosus. Method: In this study,threeyear-old A. senticosus was used as experimental samples. The growth parameters,photosynthetic parameters,and photosynthetic physiological parameters were determined to study the effects of different drought conditions on the growth and photosynthesis of A. senticosus. Result: The plant height and leaf number were significantly lower than the control group under drought stress conditions,and the leaf area was higher than the control group under drought stress. Net photosynthetic rate,stomata conductance and transpiration rate were not significantly different between the control group and the moderate drought stress group. They were significantly decreased in the severe drought stress group,while the intercellular carbon dioxide concentration increased with the severity of drought stress. With the treatment time,the initial fluorescence was higher in the severe drought stress group than in the control group,and the moderate drought stress group was lower than the control group,the maximum fluorescence was significantly lower in the severe drought stress group than in the control group,potential photochemical efficiency and maximum photochemical efficiency were significantly elevated in the moderate drought stress group. Conclusion: Drought stress can significantly inhibit the growth of A. senticosus. Severe drought conditions can significantly inhibit the photosynthesis of A. senticosus leaves. This effect is related to the regulation of stomatal size,but not related to the activity of photoreaction center.