乙酰水杨酸对增强UV-B辐射下长春花光合作用及抗氧化酶活性的影响  

Effects of Acetosalicylic Acid on Photosynthesis and Antioxidant Enzyme Activities in Catharanthus roseus Leaves under Enhanced UV-B Radiation

作　　者：张扬欢[1] 孙金春[1] 温泉[1] 张楠[1] 马红群 吴能表[1] 

机构地区：[1]西南大学生命科学学院,重庆400715 [2]成都睿智化学研究有限公司,成都610041

出　　处：《西南大学学报（自然科学版）》2011年第2期17-22,共6页Journal of Southwest University(Natural Science Edition)

基　　金：国家自然科学基金资助项目(30500041);中央高校基本科研业务费专项资金资助项目(XDJK2009C195);三峡库区生态环境教育部重点实验室自由探索基金资助项目(EF200516)

摘　　要：为探讨乙酰水杨酸(ASA)对增强UV-B辐射条件下长春花光合功能的调控作用,以长春花幼苗为试材,喷施一定浓度的乙酰水杨酸溶液,测定其在UV-B辐射增强下叶绿素含量、光合参数、叶绿素荧光参数、MDA含量及抗氧化酶活性的变化,结果表明:UV-B辐射降低了长春花叶片叶绿素含量、净光合速率(Pn)、原初光能转化效率(Fv/Fm)、光化学猝灭系数(qP)、实际光化学效率(ΦPSⅡ)及光合电子传递速率(ETR),提高了类胡萝卜素的含量和非光化学猝灭系数(qN).UV-B辐射引起了长春花叶片丙二醛(MDA)含量增加,超氧化物歧化酶(SOD)和过氧化物酶(POD)活性升高,过氧化氢酶(CAT)活性降低.2 mg/L的乙酰水杨酸处理则降低了UV-B辐射胁迫下上述指标的变化幅度.分析认为,乙酰水杨酸可能直接或间接地通过清除O2-.而使类囊体膜保持完整及光合色素免受UV-B的伤害,进而使PSⅡ维持较高的光化学活性和电子传递速率,这可能是乙酰水杨酸提高增强UV-B辐射下长春花光合速率的内在原因.In order to elucidate the regulatory roles of acetosalicylic acid（ASA） in the photosynthesis of Catharanthus roseus under enhanced UV-B radiation,the seedlings of C.roseus under UV-B radiation were foliar-sprayed with ASA,and the chlorophyll content,photosynthetic parameters,chlorophyll fluorescence parameters,MDA content and antioxiant enzyme activities were measured.The results showed that chlorophyll content,net photosynthetic rate（Pn）,conversion efficiency of primary light energy（Fv/Fm） of PSⅡ,the photochemical quenching coefficient（qP）,the quantum yield of PSⅡelectron transport（ΦPSⅡ） and photosynthetic electron transport（ETR） were decreased while carotenoids and the non-photochemical quenching coefficient（qN） were enhanced by UV-B stress.UV-B radiation also led to the increase in leaf malondialdehyde（MDA） content and the activities of superoxide dismutase（SOD） and peroxidase（POD） and the decrease in catalase（CAT） activity.A certain concentration（2 mg/L） of acetosalicylic acid alleviated the inhibition of high dosage UV-B treatment of the above-mentioned indexes,suggesting that acetosalicylic acid can remove O2-· directly or indirectly and help to preserve the integrity of thylakoid membranes and photosynthetic pigments from UV-B damage,thereby maintaining a relatively high photochemical activity of PSⅡand electron transport rate.Such might be the primary reason why acetosalicylic acid could increase the net photosynthetic rate in C.roseus leaves under enhanced UV-B radiation.

关 键 词：乙酰水杨酸 UV-B辐射 长春花 光合速率 抗氧化酶 

分 类 号：S636.1[农业科学—蔬菜学]