多年生黑麦草对Pb、Cd胁迫的响应及富集能力研究  

Response and enrichment ability of perennial ryegrass under lead and cadmium stresses

作　　者：冯鹏[1,2] 孙力[1] 申晓慧[1] 姜成[3] 李如来[1] 李增杰[1] 郑海燕[1] 张华[1] 郭伟[1] 韩旭东[1] 洪亚南[1] 

机构地区：[1]黑龙江省农业科学院佳木斯分院,黑龙江佳木斯154007 [2]黑龙江省农业科学院博士后工作站,黑龙江哈尔滨150086 [3]佳木斯大学生命科学学院,黑龙江佳木斯154003

出　　处：《草业学报》2016年第1期153-162,共10页Acta Prataculturae Sinica

基　　金：中国博士后科学基金(2013M541423);黑龙江省政府博士后项目(LBH-Z12239)资助

摘　　要：研究了铅(Pb)、镉(Cd)及Pb-Cd复合胁迫对多年生黑麦草生长发育的影响,了解多年生黑麦草修复Pb、Cd污染土壤的潜能,为农田土壤的污染修复工作提供技术支撑和应用借鉴。以人工盆栽的方法,Pb设0,300,500,1000,1500mg/kg 5个处理,Cd设0,0.3,3,10,50,100mg/kg 6个处理,Pb-Cd复合胁迫设Pb_0Cd_0,Pb_(300)Cd_0.3,Pb_(500)Cd_(0.3),Pb_(1000)Cd_(0.3),Pb_(1500)Cd_(0.3),Pb_(300)Cd_(10),Pb_(500)Cd_(10),Pb_(1000)Cd_(10),Pb_(1500)Cd_(109)个处理。测定Pb、Cd单一及复合胁迫下,多年生黑麦草种子发芽势、发芽率、发芽指数、简化活力指数,叶片叶绿素含量,净光合效率(Pn)、蒸腾速率(Tr)、光合有效辐射(PAR)、光能利用率(LUE),根、茎、叶各器官Pb、Cd含量,并计算各处理富集系数。结果表明,低浓度Pb离子(300,500 mg/kg)对多年生黑麦草种子发芽影响不显著,高浓度Pb离子(1000,1500mg/kg)抑制种子发芽,低浓度Cd离子对种子发芽势及发芽率具有促进作用,Cd离子浓度超过10mg/kg,则表现显著抑制种子发芽;Pb、Cd单一胁迫下,随Pb离子浓度的增加,叶片叶绿素含量呈递增趋势,随Cd离子浓度增加,叶绿素含量呈递减趋势。Pb离子浓度在0~1500mg/kg范围,Cd离子浓度在0~100mg/kg范围,Pb、Cd离子单一胁迫下,净光合效率均表现先降低,后升高的变化趋势,Pb浓度为1000 mg/kg时Pn达到最大值,为21.59μmol CO_2/(m^2·s);Cd浓度为10mg/kg时,Pn达到最大值,为22.67μmol CO_2/(m^2·s);Pb、Cd单一胁迫处理,随Pb、Cd浓度的增加,多年生黑麦草富集系数表现降低趋势。Pb-Cd复合胁迫对种子发芽抑制作用大于Pb、Cd单一元素胁迫;Pb、Cd及Pb-Cd复合胁迫,多年生黑麦草根、茎、叶吸收Pb、Cd离子顺序均为根>叶>茎;多年生黑麦草对Cd离子吸收富集效应较Pb离子更为显著,对轻度Pb、Cd污染土壤修复效果更为明显。The object of this study was to evaluate the effect of lead and cadmium stresses on growth and development of perennial ryegrass and to better understand the potential of perennial ryegrass for phytore mediation of Pb and Cd contaminated soils,and provide technical information for soil remediation planning.In a pot experiment,Pb was spiked at 0,300,500,1000,1500 mg/kg,and Cd was spiked at,0,0.3,3,10,50,100mg/kg.Further,Pb and Cd treatments were combined as follows:Pb_0Cd_0(CK),Pb_(300)Cd0.3,Pb_(500)Cd_(0.3),Pb_(1000)Cd_(0.3),Pb_(1500)Cd_(0.3),Pb_(300)Cd_(10),Pb_(500)Cd_(10),Pb_(1000)Cd_(10),Pb_(1500)Cd_(10).Measurements made included germination vigor,an establishment rate index,chlorophyll content,photosynthetic rate,transpiration,water use efficiencies of seedlings,as well as photosynthetically active radiation,and light use efficiency.The Pb and Cd contents of root,stem and leaf were determined in the seedlings.Compared to CK,there was no significant difference in germination at lower concentrations(300,500mg/kg)of Pb stress,but there was an adverse effect at higher concentrations(1000,and 1500 mg/kg).Lower concentrations of Cd stress promoted seed germination,but where Cd concentration was more than 10mg/kg,there was inhibition of seed germination.With increase in Pb concentration,chlorophyll content also increased,but Cd stress the opposite tendency was noted.Photosynthetic rate decreased at lower concentrations and then increased at higher concentration under Pb or Cd single stress.Photosynthetic rate peaked when Pb concentration was 1000mg/kg or Cd concentration was 10mg/kg.The enrichment coefficient decreased with increase in concentration of the metals Pb or Cd.The Pb and Cd combinations showed stronger inhibitory effects on seed germination than single metal exposure stress.The enrichment ability of perennial ryegrass to Pb and/or Cd was root>stem>leaf.The enrichment coefficient of Cd was greater than that of Pb.Perennial ryegrass showed a better remediative effect on lightly polluted soils.

关 键 词：铅 镉 胁迫 多年生黑麦草 富集能力 

分 类 号：Q945.78[生物学—植物学]