条浒苔和缘管浒苔对镉胁迫的生理响应比较
DOI:
作者:
作者单位:

作者简介:

通讯作者:

中图分类号:

基金项目:

国家支撑项目(2008BAD95B05); 浙江省近岸水域生物资源开发与保护重点实验室开放课题(2010F30003); 江苏省海洋生物学重点实验室开放课题(JSMK2008-002);江苏省海洋资源开发研究院科技开发基金项目(JSIMR09B10)


Comparative physiological responses of cadmium stress on Enteromorpha clathrata and Enteromorpha linza
Author:
Affiliation:

Fund Project:

  • 摘要
  • |
  • 图/表
  • |
  • 访问统计
  • |
  • 参考文献
  • |
  • 相似文献
  • |
  • 引证文献
  • |
  • 文章评论
    摘要:

    为探讨大型海藻对重金属胁迫的生理响应及耐受机制,以条浒苔(Enteromorpha clathrata)和缘管浒苔(Enteromorpha linza)为试验材料,研究了不同浓度的镉(Cd2+)处理7 d对浒苔的生长、叶绿素(Chl)和类胡萝卜素(Car)含量、叶绿素荧光参数、可溶性糖(SS)和可溶性蛋白(SP)含量的影响。结果表明:随着Cd2+浓度的增加,条浒苔和缘管浒苔鲜重(FW)和相对生长速率(RGR)与对照相比显著下降,且条浒苔的FW和RGR降低幅度均大于缘管浒苔的。镉胁迫下, Chl和Car含量、 Chl a/Chl b、PSⅡ最大光能转化效率(Fv/Fm)、PSⅡ实际光能转化效率(Yield)、最大相对电子传递速率(rETRmaxPm)和光能利用效率(α)、SP含量随着Cd2+浓度的升高均出现下降趋势,除了Chl外,条浒苔的其它指标的降幅要大于缘管浒苔。随着镉胁迫强度的增加,浒苔SS含量呈现逐渐上升。相关分析显示,生长指标除了与Chl/Car无明显的相关性,与SS含量呈显著负相关外,与Chl、Car、Chla/Chlb、Fv/Fm、Yield、rETRmaxα和SP均呈极显著正相关(P<0.01)。上述表明,条浒苔和缘管浒苔对Cd2+胁迫均较敏感,而维持较高的Car含量、Chla/Chlb、Fv/Fm、Yield、rETRmaxα、SS含量、SP含量是缘管浒苔对镉耐性高于条浒苔的重要原因。 而叶绿素含量、类胡萝卜素含量、叶绿素a/叶绿素b、Fv/Fm、Yield、rETRmax、α、可溶性蛋白和可溶性糖含量等均可以作为浒苔耐镉性的评价指标。

    Abstract:

    Cadmium pollution is one of the most extensive and harmful environmental problems all over the world. In recent years, with the continuous economic development, pollution by cadmium and other heavy metals in the coastal water body is becoming more serious. To investigate macroalgae physiological response to heavy metals and its resistant mechanisms, experiments were carried out to study the effects of different cadmium levels on growth, Chlorophyll (Chl) and Carotenoid (Car) contents, Chlorophyll fluorescence parameters, soluble sugar (SS) and soluble protein (SP) contents in Enteromorpha clathrata and Enteromorpha linza. The results were obtained as follows. (1) Growth of two Enteromorpha was sensitive to cadmium stress. With the increase of Cd2+ concentrations, the fresh weight (FW) and relative growth rate (RGR) of E. clathrata and E. linza were both decreased significantly. However, inhibiton of FW and RGR in E. clathrata was more serious than that in E. linza. (2) Chl and Car contents of E. clathrata and E. linza were decreased significantly upon treatment with 20 μmol/L Cd2+; When Cd2+ concentrations increased gradually, Chl and Car contents of two Enteromorpha were decreased more significantly, however, Car contents in E. clathrata decreased more significantly than those in E. linza under all Cd2+ treatments. Chlorophyll a/Chlorophyll b (Chla/Chlb) of E. clathrata and E. linza decreased gradually as Cd2+ concentration increased. However, the former (ie. E. clathrata) decreased more significantly than the latter. Chlorophyll/Carotenoid of E. clathrata was increased gradually as Cd2+ concentration increased; it reached the highest value when treated with Cd2+ at 60 μmol/L, and it started to decrease gradually when Cd2+ concentration increased further more; while Chlorophyll/Carotenoid of E. linza showed no significant change with all treatments of Cd2+. (3) With the increase of Cd2+ concentrations, the maximal photochemical efficiency of PSⅡ(Fv/Fm), the actual photochemical efficiency of PSⅡ in the light (Yield), the maximal relative electron transport rate (rETRmax, Pm) and light use efficiency (α) of both Enteromorpha varieties were decreased significantly. The Pm decrease was much more than the decrease of Fv/Fm, Yield or α in both Enteromorpha. All chlorophyll fluorescence parameters of E. clathrata were decreased more than those of E. linza. (4) Compared with control, the soluble sugar (SS) contents decreased significantly in both Enteromorpha under 20 μmol/L Cd2+ stress. When Cd2+ concentrations were increased, the SS contents of both Enteromorpha were increased too, but the SP contents showed a significant decline. The SS contents of E. linza were higher than those of E. clathrata, but the SP contents of E. linza decreased less obviously than those of E. clathrata. (5) The results also showed no significant correlation between growth indices and Chl/Car, significant and highly significant negative correlation between growth indices and SS content, highly significant positive correlations between growth indices and Chl content, Car content, Chla/Chlb ratio, Fv/Fm, Yield, rETRmax, α and SP content. The above results leads us to a conclusion that E. clathrata and E. linza were both sensitive to Cd2+. However, Growth inhibition of E. clathrata was more than that of E. linza by Cd2+ stress. Better adaptation of E. linza to Cd2+ was mainly achieved by its higher Car contents, Chla/Chlb, Fv/Fm, Yield, rETRmax, α, SS contents and SP contents upon exposure to Cd2+ stress. Chl content, Car content, Chla/Chlb ratio, Fv/Fm, Yield, rETRmax, α, SP and SS content can regard as value indexes of cadmium tolerance of Enteromorpha.

    参考文献
    相似文献
    引证文献
引用本文

蒋和平,郑青松,朱明,刘兆普,姚瑶,刘国红.条浒苔和缘管浒苔对镉胁迫的生理响应比较.生态学报,2011,31(16):4525~4533

复制
分享
文章指标
  • 点击次数:
  • 下载次数:
  • HTML阅读次数:
  • 引用次数: