盐胁迫对盐生杜氏藻生长及叶绿素荧光特性的影响3期王帅,等:盐胁迫对盐生杜氏藻生长及叶绿素荧光特性的影响35

Effects of Salt Stress on The Growth and Chlorophyll Fluorescence of Dunaliella salina

以盐生杜氏藻（Dunaliella salina）为实验材料,研究在不同盐度（5,10,20,30,40,50,60,70,80,90,100,110,120,130）下处理不同时间后（12、24和48h）,该藻的生长及叶绿素荧光特性的变化情况。结果表明,盐生杜氏藻生长和进行光合作用的最适盐度为100,适宜盐度范围为20-110。在盐度过低（〈20）和过高（〉110）的胁迫条件下,盐生杜氏藻PSII的荧光指标（Fv/Fm、ΦPSII、Fv/Fo和rETR）显著降低。该藻的细胞密度和叶绿素含量均在盐度100时达到最大值。相关性分析结果表明,盐生杜氏藻的荧光指标（Fv/Fm、ΦPSII、Fv/Fo和rETR）与细胞密度呈极显著的正相关性,因此可通过PSII荧光指标的变化来反映该藻对盐胁迫的耐受性。本文还对盐胁迫下盐生杜氏藻的响应机制和叶绿素荧光技术在筛选耐盐微藻品种中的应用进行了初步探讨。

In this experiment,the changes in growth and fluorescence characteristics of Dunaliella salina after exposure to different salinities（5,10,20,30,40,50,60,70,80,90,100,110,120 and 130）were investigated at different times（12,24 and 48h）.The results showed that the optimal salinity for the growth and photosynthesis of D.salina was 100.The optimum salinity ranged from 20 to 110.Both low（20）and high（110）salinity stress caused a strong depression of the fluorescence parameters（Fv/Fm,ΦPSII,Fv/Foand rETR）in D.salina.The cell density and chlorophyll content of D.salinareached the highest at salinity 100.The fluorescence parameters（Fv/Fm,ΦPSII,Fv/Foand rETR）of D.salinapositively correlated with cell density.Therefore,the tolerance of D.salinato salt stress could be reflected by the PSII fluorescence parameters.The response mechanism of D.salinaunder salt stress and the possibility of determining the salt resistance of marine microalgae using chlorophyll fluorescence technique were also discussed.