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作 者 ：朱喜锋¹;邹定辉^1,2;简建波¹;陈伟洲¹;刘慧慧¹;杜虹¹

期 刊 ：应用生态学报 2009年 20卷 06期 页码：1438-1444

关键词：龙须菜；

摘 要 ：研究了大型海藻龙须菜(Gracilaria lemaneiformis)对不同浓度重金属铜(0、25、50、100、250和500 μg·L^-1)胁迫的生理响应.结果表明:当Cu²⁺浓度≥50 μg·L^-1时，龙须菜藻体的相对生长速率显著下降，最大光化学量子产量、最大相对电子传递速率和相对电子传递效率呈相同的变化趋势.随着Cu²⁺浓度的升高，龙须菜藻体最大净光合速率和光饱和点显著降低，而光补偿点显著升高，叶绿素a、类胡萝卜素和藻胆蛋白含量则呈先升高后下降的趋势；当Cu²⁺浓度达到500 μg·L^-1时，叶绿素a、类胡萝卜素和藻胆蛋白含量显著下降.说明龙须菜在低浓度Cu²⁺胁迫下具有一定的抵抗能力，而当Cu²⁺浓度≥50 μg·L^-1时，会对藻体生理活动造成显著的抑制作用.

Abstract:Gracilaria lemaneiformis was exposed to 0, 25, 50, 100, 250 and 500 μ
g·L-1 of Cu2+ to study its physiological responses to Cu2+ st
ress. When the Cu2+ concentration was ≥50 μg·L-1, the relative gr
owth rate (RGR) of G. lemaneiformis decreased significantly, and the optimal
quantum yield (Fv/Fm), the maximum relative electron transfer rate (r
ETRmax), and the relative electron transfer efficiency (α) exhibited th
e same variation trend, compared with the control. With the increase of Cu2+
 concentration, the maximum net photosynthetic rate (Pmax) and l
ight saturation point (LSP) decreased significantly, light compensation poin
t (LCP) had a significant increase, while chlorophyll a, carotenoid, and phy
cobiliprotein contents decreased after an initial increase. When the Cu2+
concentration reached 500 μg·L-1, the chlorophyll a, carotenoid, and phy
cobiliprotein contents decreased significantly. It was suggested that G. leman
eiformis could tolerate low concentration Cu2+ stress, but its physiolog
ical activities were inhibited markedly when exposed to ≥50 μg·L-1 of C
u2+.

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