摘要
为明确低温胁迫后恢复过程中水杨酸(SA)对植物光合特性的影响,以黄瓜品种‘津研四号’幼苗为材料,通过沙培试验,研究了外源SA对夜间5℃低温胁迫后常温(25℃)恢复中黄瓜幼苗叶绿素含量、光合速率、叶绿素荧光参数、气体交换参数等的影响。结果显示:(1)与喷施清水处理相比,外源SA处理显著促进了夜间低温胁迫后的常温(25℃)恢复效果,显著提高了恢复速度和水平,表现在黄瓜幼苗叶绿素含量、净光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)和胞间CO2浓度(Ci)显著升高,黄瓜幼苗净光合速率在恢复6h时达到对照水平的82.18%。(2)外源SA还明显加快了恢复过程中黄瓜幼苗叶片最大光化学效率(Fv/Fm)、实际光化学效率(ΦPSⅡ)及非循环电子传递速率(ETR)的恢复,提高了非光化学猝灭系数(NPQ)值,增强了幼苗自身光保护能力。(3)外源SA也促进了黄瓜幼苗叶片表观量子效率(AQY)和羧化效率(CE)的恢复,它们在恢复2d时分别达到对照水平的92.59%和90.62%。研究表明,在夜间低温胁迫后的常温恢复过程中,外源SA可有效地促进黄瓜幼苗光合作用的恢复,增强其对低温环境的适应能力。
To figure out the effects of SA on plant photosynthesis characteristics during the recovery of the day after night chilling,with the ‘Jinyou no.4 ’ cucumber seedlings as materials,we studied the effect of exogenous SA on chlorophyll content,photosynthetic rate,chlorophyll fluorescence parameters and gas exchange parameters etc during the recovery（25 ℃） of the day after night chilling（5 ℃） using sand culture.The results showed that：（1）The exogenous SA treatment significantly promoted the normal temperature （25 ℃） recovery after night chilling stress,significantly improved the speed and level of recovery compared with H2O treatment,which significantly increased contents of chlorophyll,net photosynthetic rate （Pn）,transpiration rate（Tr）,stomatal conductance （Gs）,and the intercellular CO2 concentration（Ci）.At recovery 6 h,the photosynthetic rate of cucumber seedlings reached 82.18％ of control levels.（2）The exogenous SA significantly increased Fv/Fm,ΦPsⅡ and ETR,which improved the NPQ value and enhanced light protec tion.（3）Exogenous SA also contributed to the recovery of the apparent quantum yield（AQY） and carboxylation efficiency （CE） in cucumber seedlings,when recovery 2 d,AQY and CE of cucumber leaves return to 92.59 ％ and 90.62％ of control levels.Therefore,during recovery after night chilling stress,exogenous SA treatment could promote the recovery of photosynthesis of cucumber seedlings,and enhance its ability to adapt to chilling stress.
出处
《西北植物学报》
CAS
CSCD
北大核心
2014年第7期1419-1425,共7页
Acta Botanica Boreali-Occidentalia Sinica
基金
安徽省自然科学基金(1208085QC55)
安徽科技学院引进人才基金(ZRC2009250)
关键词
夜间低温
SA
黄瓜幼苗
光合速率
恢复
night chilling
salicylic acid
cucumber seedlings
photosynthesis rate
recovery
