镉胁迫对龙葵幼苗光合特性和营养元素吸收的影响  

Effect of cadmium on photosynthesis and nutrient elements uptake of Solanum nigrum L. seedlings

作　　者：郭智[1,2] 原海燕[3] 奥岩松[1] 

机构地区：[1]上海交通大学农业与生物学院植物科学系,上海200240 [2]江苏省农业科学院农业资源与环境研究所,江苏南京210014 [3]江苏省中国科学院植物研究所(南京中山植物园),江苏南京210014

出　　处：《生态环境学报》2009年第3期824-829,共6页Ecology and Environmental Sciences

基　　金：上海市科学技术委员会科技攻关计划(07DZ19604)

摘　　要：采用模拟镉污染土壤培养法研究了镉对龙葵(Solanum nigrum L)幼苗光合特性及营养元素吸收的影响。结果表明:镉处理显著降低龙葵幼苗叶片色素含量。T1-T4镉处理下,龙葵叶绿素a、叶绿素b和类胡萝卜素含量的降幅分别为4.53%～32.39%、5.12%～29.89%和4.54%～19.82%。随镉处理浓度的增加,龙葵幼苗叶片净光合速率(Pn)、气孔导度(Gs)和蒸腾速率(Tr)均呈下降趋势,T1-T4镉处理下,分别较对照(CK)下降6.01%～61.71%、17.94%～55.32%和17.68%～68.10%,而胞间CO2浓度(Ci)则增加8.19%～30.04%。同时,可变荧光和最大荧光之比(Fv/Fm)显著降低。镉处理还导致龙葵植株营养元素吸收紊乱。镉促进龙葵叶片和根系K吸收,对Na吸收影响不显著。同时,镉促进根系Mg吸收,但抑制其向地上部转运。低浓度镉处理促进叶片Ca吸收。龙葵根、茎、叶Zn含量随镉处理浓度的提高均表现为低促高抑。根系Cu吸收随镉浓度提高而增加,叶片先增后降,各器官Fe含量随镉浓度提高逐渐降低,而根系Mn含量受镉抑制。Effects of Cd stress on the leaf photosynthesis and macro- and micro-nutrient elements uptake in the hyperaccumulator plant Solanum nigrum L were investigated in a soil pot experiment. Results showed that Cd significantly decreased leaf pigments contents ofS. nigrum seedlings. Under T1-T4 Cd treatments, the Chla, Chlb, and Car contents decreased, respectively, 4.53%-32.39%, 5.12%-29.89%, and 4.54%-19.82%. Under these treatments, net photosynthesis rate （Pn）, stomatal conductance （Gs）, and transpira- tion rate （Tr） decreased respectively, 6.01%-61.71%, 17.94%-55.32%, and 17.68%-68.10%; while intercellular CO2 concentration （Ci） increased 8.19%-30.04%. Significant Fv/Fm decrease was also observed in these Cd treatments. Moreover, Cd application led to a disturbance of macro- and micro-nutrient elements uptake. Cd application increased K content in both S. nigrurn root and shoot, but had no significant effect on Na. Mg content were increase in nigrum root but not in shoot. Moreover, low Cd concentration treatment increased Ca content in the leaves of 5： nigrum. Zn content in the roots, stems, and leaves were increased under low Cd treatment, while high Cd decreased them. Following the T1-T4 treatment, Cu content in root was increased, but in leaf it increased firstly and then decreased. Furthermore, Fe content in the root, stem, and leaf decreased with increasing Cd concentration in the soils. Cd significantly decreased Mn concentration in the root ofS. nigrum.

关 键 词：龙葵(Solanum nigrum L) 镉 光合特性 营养元素 

分 类 号：X171.5[环境科学与工程—环境科学] Q945.78[生物学—植物学]