高温对海带(Saccharina japonica)抗氧化酶及叶绿素荧光参数的影响

Effects of High Temperature on the Antioxidant Enzymes and Chlorophyll Fluorescence Parameters of Saccharina japonica

中文关键词: 海带  高温  抗氧化酶  叶绿素  叶绿素荧光

英文关键词: Saccharina japonica  High temperature  Antioxidant enzyme  Chlorophyll  Chlorophyll fluorescence

中文摘要:

      以海带(Saccharina japonica)幼苗为材料，研究了高温(25℃)条件下其抗氧化酶、叶绿素含量、叶绿素荧光参数的变化。研究表明，(1)高温组的可溶性蛋白含量在处理12 h后达最大值(P<0.05)，相比初始含量升高了37.9%。(2)随着胁迫时间的延长，高温组的丙二醛(MDA)含量呈增加趋势，在48 h时达最大值，与对照组差异显著(P<0.05)。(3)高温组海带幼苗的叶绿素含量随胁迫时间延长呈下降趋势，胁迫48 h时，叶绿素含量达最小值，与初始值相比下降了38.5% (P<0.05)。 (4)在高温条件下，过氧化物酶(POD)活性随胁迫时间延长逐渐下降，在48 h时达最小值，与初始值相比下降47.2%，呈显著性差异(P<0.05)；超氧化物歧化酶(SOD)活性呈现波动趋势，处理8 h后，SOD活性达最小值；40 h后，SOD活性达最大值，与初始值相比上升了36% (P<0.05)。过氧化氢酶(CAT)活性随胁迫时间延长呈下降趋势，处理36 h后，海带幼苗的CAT活性略有升高；处理48 h后，CAT活性达最小值，与初始值相比下降了75.8% (P<0.05)。(5)高温条件下，海带幼苗的光化学最大量子产量(Fv/Fm)随着胁迫时间延长呈现下降趋势，处理48 h后，高温组的Fv/Fm达最小值，与初始条件相比下降了56.8%，呈显著性差异(P<0.05)。本研究可为海带的耐高温品种选育提供理论依据。

英文摘要:

      The aim of this study was to identify the effects of high temperature (25℃) on the activity of antioxidant enzymes, the chlorophyll content, and the chlorophyll fluorescence parameter of Saccharina japonica young sporophytes. Samples were taken every 4 h over a 48 h period. The major results included: (1) after 12 h culture the content of soluble proteins of the 25℃ group reached the maximum value that was 37.9% higher than initial level (P<0.05). (2) MDA content of the 25℃ group increased over the time and reached the highest value after 48 h, which was significantly different from the control group (P<0.05). (3) The chlorophyll content of the 25℃ group decreased during prolonged culture, the lowest value appeared after 48 h and was 38.5% lower than the initial level (P<0.05). (4) At high temperature the POD activity decreased over the time, the minimum appeared after 48 h and was 47.2% lower than initial (P<0.05); The SOD activity fluctuated, reached the minimum after 8 h, and the maximum activity was observed after 40 h which was 36% higher than the initial level (P<0.05); The CAT activity declined to the lowest level after 48 h and was 75.8% lower than initial (P<0.05). (5) The value of Fv/Fm of the 25℃ group dropped to the lowest after 48 h and was 56.8% lower than initial (P<0.05). Our results provide important information for the selection of heat-resistant S. japonica.