镉胁迫下两种菊芋幼苗的光合作用特征及镉吸收转运差异的研究  

Effect on the photosynthetic characteristics of Cd uptake and translocation in seedlings of two Helianthus tuberosus varieties

作　　者：陈良[1] 隆小华[1] 郑晓涛[1] 刘兆普[1] 

机构地区：[1]南京农业大学资源与环境科学学院江苏省海洋生物学重点实验室,江苏南京210095

出　　处：《草业学报》2011年第6期60-67,共8页Acta Prataculturae Sinica

基　　金：公益性行业(农业)科研专项经费项目(200903001-05);国家"948"项目(2009-Z9);国家重大支撑项目(2011BAD13B09);江苏省科技支撑项目(BE2011368和BE2010305);教育部博士点基金(20100097120016);中央高校基本业务费项目(Y0201100249)资助

摘　　要：本试验旨在探讨利用菊芋修复重金属镉(Cd)污染的可能性,研究2种菊芋———南芋5号(NY5)和南芋2号(NY2)在不同浓度(0,5,25,50,100和200mg/L)Cd处理下光合作用特征,并比较其对镉的吸收转运差异性。结果表明,1)NY5和NY2在Cd胁迫下生物量明显降低,但NY5生物量的降低幅度明显小于NY2;2)NY5和NY2的叶绿素a和叶绿素b含量均分别在100和25mg/L Cd胁迫下达到最低值,NY5的类胡萝卜素含量在Cd胁迫下较对照均增大,NY2则相反,总体上随Cd浓度的增加呈下降趋势;3)在Cd胁迫下,2种菊芋幼苗净光合速率(Pn)、气孔导度(Gs)、蒸腾速率(Tr)均明显下降,胞间CO2浓度(Ci)比较稳定,NY5的水分利用效率(WUE)和气孔限制值(Ls)变化趋势极其相似,在50mg/L时达到最低值,而NY2的WUE和Ls变化不大;4)2种菊芋对Cd的富集效果较好,NY5较NY2耐镉性和富集性强。由此可见,菊芋对镉有较强的吸收富集能力,利用菊芋修复镉污染具有较好前景。The photosynthetic characteristics and Cd accumulating capacities of two Helianthus tuberosus varieties（NY5,NY2） at different Cd concentrations（0,5,25,50,100,and 200 mg/L）,were investigated for the potential use of H.tuberosus as a candidate for phytoremediation of Cd-contaminated soils.1） The biomass of NY5 and NY2 were significantly reduced by Cd stress,but the reduction was less for NY5 than for NY2.2） The chlorophyll content of NY5 was lowest in the 100 mg/L Cd treatment,while for NY2,the lowest value was observed in the 25 mg/L Cd treatment.The carotenoids content of NY5 under Cd stress was higher than that of the control,while the opposite was observed for NY2.3） With the increase in Cd concentration,net photosynthetic rate（Pn）,stomatal conductance（Gs） and transpiration rate（Tr） significantly decreased,but the intercellular CO2 concentration（Ci） was relatively stable.Water use efficiency（WUE） and stomatal limitation（Ls） of NY5 showed similar change trend under Cd stress with the lowest value observed at 50 mg/L Cd,while for NY2,there was little change.4） NY5 and NY2 had Cd tolerance and accumulation capacity at high concentrations of Cd stress,but the capacity of NY5 was greater than that of NY2.H.tuberosus may therefore be an excellent candidate for phytoremediation on Cd-contaminated soils,and NY5 may be better than NY2.

关 键 词：镉胁迫 菊芋 光合特征 镉吸收转运 

分 类 号：S632.9[农业科学—蔬菜学] X173[农业科学—园艺学]