| 摘要: |
| 与低温黑暗处理相比 ,低温弱光处理使黄瓜叶片的放氧活性显著降低,2℃黑暗处理 6.5h后黄瓜叶片的放氧活性降低到处理前的66% ,2℃35μmol/(m2·s)处理6.5h后则降低到处理前的- 50 %。研究结果显示 ,在 5℃低温条件下 100 μmol/(m2·s)光照使黄瓜发生下列变化 :叶片毫秒延迟发光的慢相强度显著降低 ;从叶片中提取的叶绿体的PSⅡ及 PSⅠ+PSⅡ的电子传递速率显著升高;加 NH4Cl和加 ADP+Pi的 Hill反应活性与基础 Hill反应活性相差不大;从叶片中提取的叶绿体 9- AA荧光猝灭能力消失。以上结果证明低温下光照处理使黄瓜类囊体膜解耦联。 |
| 关键词: 黄瓜,低温,弱光,类囊体膜,解耦联 |
| DOI： |
| 分类号:S642.201 |
| 基金项目:国家重点基础研究发展规划项目资助(G1999011708) |
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| Effect of low temperature and low light treatment on the coupling state of cucumber thylakoid membrane |
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CHEN Qi-lin1,SHAN Lun2,CHENG Zhi-hui1,SHEN Yun-gang3,CHEN Qi-lin1,SHAN Lun2,CHENG Zhi-hui1,SHEN Yun-gang3,CHEN Qi-lin1,SHAN Lun2,CHENG Zhi-hui1,SHEN Yun-gang3
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| Abstract: |
| In contrast to treatmentwith low temperature and darkness, treatment of cucumber leaveswith low temperature and low light reduced oxygen evolution activity dramatically.While 2℃& darkness for 6.5 h reduced cucumber leaf oxygen evolution activity to 66% of pre-treatment, 2℃treatment in 35μmol/(m2·s) reduced to -50% of that of the control. The results indicated that illum ination with 100μmol/(m2·s) superimposed on 5℃ low temperature made m illisecond delayed em ission (ms-DLE) from cucumber leaf decrease significantly, that the chloroplants isolated from such treated leaves showed electron transport rate of PSⅠand PSⅠ+PSⅡincreased.Their uncoupled Hill reaction activity with NH4Cl was nearly equal to basic Hill reaction activity without NH4Cl and coupled Hill reaction activity with addition ofADP+ Pi. In addition, chloroplasts from thus treated leaves almost lost the ability to quench 9-AA flourescence. It is concluded that thylakoids from cucumber leaves treated with low temperature and low light were in uncoupled state. |
| Key words: cucumber (Cucumis sativus L.),low temperature,low light,thylakoid membrane,uncoupling |
