Zhu Xi-Feng, Zou Ding-Hui, Jian Jian-Bo, Chen Wei-Zhou, Liu Hui-Hui, Du Hong
Institute of Marine Biology, Shantou University, Shantou 515063, Guangdong, China.
Ying Yong Sheng Tai Xue Bao. 2009 Jun;20(6):1438-44.
Gracilaria lemaneiformis was exposed to 0, 25, 50, 100, 250 and 500 microg x L(-1) of Cu2+ to study its physiological responses to Cu2+ stress. When the Cu2+ concentration was > or = 50 microg x L(-1), the relative growth rate (RGR) of G. lemaneiformis decreased significantly, and the optimal quantum yield (Fv/Fm), the maximum relative electron transfer rate (rETRmax), and the relative electron transfer efficiency (alpha) exhibited the same variation trend, compared with the control. With the increase of Cu2+ concentration, the maximum net photosynthetic rate (Pmax) and light saturation point (LSP) decreased significantly, light compensation point (LCP) had a significant increase, while chlorophyll a, carotenoid, and phycobiliprotein contents decreased after an initial increase. When the Cu2+ concentration reached 500 microg x L(-1), the chlorophyll a, carotenoid, and phycobiliprotein contents decreased significantly. It was suggested that G. lemaneiformis could tolerate low concentration Cu2+ stress, but its physiological activities were inhibited markedly when exposed to > or =50 microg x L(-1) of Cu2+.
将龙须菜暴露于0、25、50、100、250和500微克/升的Cu2+中，以研究其对Cu2+胁迫的生理响应。当Cu2+浓度≥50微克/升时，龙须菜的相对生长速率（RGR）显著降低，与对照组相比，最佳量子产量（Fv/Fm）、最大相对电子传递速率（rETRmax）和相对电子传递效率（α）呈现相同的变化趋势。随着Cu2+浓度的增加，最大净光合速率（Pmax）和光饱和点（LSP）显著降低，光补偿点（LCP）显著升高，而叶绿素a、类胡萝卜素和藻胆蛋白含量在最初增加后下降。当Cu2+浓度达到500微克/升时，叶绿素a、类胡萝卜素和藻胆蛋白含量显著下降。结果表明，龙须菜能够耐受低浓度的Cu2+胁迫，但当暴露于≥50微克/升的Cu2+时，其生理活动受到明显抑制。
