| 摘要: |
| 实验用盐藻取自天津塘沽轻工业部制盐研究所，采用ASP2培养液为培养基，研究了盐藻的室温光抑制现象，并探讨了盐藻的光保护反应机理。结果表明，盐藻对高辐照有很强的忍耐力，且光合能力的恢复也很强，氯霉素（CAP）或二硫苏糖醇（DTT）在高光下强烈地加深了对PSII光化学效率（Fv／Fm）和光合量子效率（Φi）的抑制，但CAP或DTT单独作用并不抑制盐藻的光化学系统在低光下的可逆恢复；盐藻在 CAP+DTT共同作用下抑制的程度最深，且光抑制撤除后在低光下的恢复明显减慢，但也不能完全阻止它的恢复。经UTT、CAP＋UTT处理的盐藻在高光下，非光化学荧光猝灭缓慢增加，PSII还原态降低。讨论了低温和光对盐藻光化学效率恢复的影响。 |
| 关键词: 盐藻 光抑制 PSII光化学效率 非光化学荧光猝灭 PSII还原态 |
| DOI：10.11693/hyhz200001007007 |
| 分类号: |
| 基金项目:中国科学院院长基金 |
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| PHOTOINHIBITION AT ROOM TEMPERATURE IN DUNALIELLA SALINA 1009 |
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XIA Li, CHEN Yi-zhu
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Institute of South China Botany, The Chinese Academy of Sciences, Guangzhou, 510650
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| Abstract: |
| Dunaliella salina 1009 possesses a greater tolerance to high irradiance and has a much high rate of photosynthesis after photoinhibition. Changes in photosynthesis rate and photochemical characteristics in response to high irradiance, followed by recovery at low irradiance, were determined in four groups of Dunaliella salina 1009. They were untreated algae, algae treated with either an inhibition of energy dissipation associated with the Xanthophyll cycle (DTT) or an inhibition of ecoded protein synthesis (CAP), as well as algae treated with a combination of CAP+DTT. Treatment of algae with either CAP or DTT resulted in a more pronounced decrease in the rate of photosynthesis subsequent to the treatment at high PFD, but the depression of photochemical efficiency and photo efficiency of photosynthetic oxygen evolution was reversible, i.e., CAP or DTT sensitive process did not prevent the rapid recovery of photochemical system. However, subsequent to the same exposure, the highest level of depression and a low recovery was observed when these algae were treated with a combination of CAP+DTT. This means that CAP- or DTT-sensitive process is not completely related in Dunaliella salina 1009. Meanwhile, in algae treated with CAP+DTT, DTT, further decrease in the PSII reduction state, as well as the slow decrease in Fm' (the slow increase in non-photochemical quenching), would be consistent with the development of an additional Xanthophyll cycle independent process that dissipates excess energy in PSII. This apparently develops during high PFD and persists upon return to low PFD. It may cause the photochemical system to reversibly return to a high functional photosynthetic state. |
| Key words: Dunaliella salina 1009, Photoinhibition, PSII photochemical efficiency, Non-photochemical quenching, PSII reduction state |
