SO_2胁迫对紫丁香和连翘叶片生理生化指标的影响

Effects of sulfur dioxide stress on the physiological indexes of leaves of Syringa oblata and Forsythia suspensa

采用两种SO2浓度对紫丁香(Syringa oblata)和连翘(Forsythia suspensa)截枝进行熏气处理,分析了叶片中叶绿素a、叶绿素b和叶绿素(a+b)含量的动态变化以及叶绿素(a+b)与细胞汁液pH值、细胞质膜相对透性(PMP)、脯氨酸(Pro)、丙二醛(MDA)和可溶性糖(SS)含量的相关性.结果表明,在10 mg/m3和30 mg/m3SO2浓度胁迫下,随着胁迫时间的延长和浓度的增加,叶绿素总量有所上升,膜脂过氧化产物丙二醛含量明显增加,细胞质膜相对透性明显增大,脯氨酸含量先降低而后升大,可溶性糖含量有所增大,细胞汁液pH值变小.经相关分析表明,叶绿素含量与可溶性糖、丙二醛含量和细胞汁液pH值呈显著正相关,而与脯氨酸含量呈显著负相关.

SO2 is one of primary pollutant in urban environments, and usually leads to the afforestation plant changes in morphology, structure and physiological metabolism. The branches of Syringa oblata and Forsythia suspensa were fumigated with SO2 of different concentrations and different time as well. Then the dynamic changes of chlorophyll a, b and（a＋b）content in the leaves were detected, aiming at revealing the correlations of chlorophyll content to other physiological indexes such as malondialdhyde（MDA）,proline,（Pro）,plasma membrane permeability（PMP）,pH of the cellular juice and soluble sugar（SS）contents. The results showed that along with the prolongation of stress time and the increasing of the SO2 concentration,chlorophyll content, MDA, PMP and SS were all increased. However, Pro content decreased initially and then increased, but the cellular juice pH decreased. According to correlation analysis, the chlorophyll content had significant positive correlations to SS,MDA and pH of the cellular juice, but a significant negative correlation to Pro content.