中文摘要：

通过叶绿素荧光技术和气体交换测量技术,研究了铜胁迫对菜豆（Phaseolus vulgaris.L）幼苗叶片叶绿素荧光及光合气体交换的影响.结果表明：铜胁迫处理菜豆幼苗24h,并未对光适应下叶片的最大光化学量子产率（F′v/F′m）、PSⅡ的实际的量子效率（ΦPSⅡ）、光合电子传递速率（RET）、光化学猝灭系数（qP）和非光化学猝灭系数（CNPQ）造成显著性影响.气孔导度（Gs）和细胞间CO2浓度（Ci）在上述处理下也未发生显著性变化,但净光合速率（Pn）显著下降.铜胁迫处理菜豆幼苗48h后,F′v/F′m,ΦPSⅡ,RET,qP均显著下降,而CNPQ和Ci有所上升;净光合速率（Pn）进一步下降,但气孔导度（Gs）未发生显著性变化.说明光合固定CO2较光系统Ⅱ对于铜胁迫更加敏感,延长铜胁迫的时间均可对二者产生抑制作用.

英文摘要：

The effects of copper stress on the chlorophyll fluorescence and photosynthetic gas exchanges of bean leaves （Phaseolus vulgaris. L） were studied in the present work. The results showed that copper stress for 24 h had no significant effects on maximal PSⅡ quantum yield of light adaptation （F′v/F′m）, effective PSⅡ quantum yield （ ΦPSⅡ ）, photosynthetic electron transfer rate （Rr＋）, photochemical quenching （qP）, non-photochemical quenching （CNpQ）, stomatal conductance （G,）, and intracellular COz concentration （Ci） of the leaf. However, the same. treatment caused a significant decrease of net photosynthesis rate （P,,）. After treatment with copper stress for 48 h, the values of ,F′v/F′m,ΦPSⅡ,RET and qP were significantly decreased,while CNpQ and C1 increased to some extent. Copper stress for 48 h caused further decrease of Pn but had no significant effect on G. These results indicate that photosynthetic CO2 fixation Could be more sensitive to copper stress than photosystem Ⅱ , but an increase in the times of copper stress would inhibit photosynthetic COz fixation and the operation of photosystem Ⅱ.