中国生态农业学报2016，Vol.24Issue(4)：517-523,7.DOI:10.13930/j.cnki.cjea.151045
不同锌水平对低剂量镉在水稻中迁移能力的影响*
Effectsofzinclevelonlowdosecadmiumtransportinriceplant
摘要
Abstract
Theinteractionofzinc(Zn)andcadmium(Cd)insoiliscriticalfortheuptakeandtransportofCdinriceplants.However,theeffectofZnlevelsontheinteractionsofZnandCdorontherateoftransportofCdinriceplantsisstillnotentirelyclear.Inthisstudy,riceplantbiomass,andCdtransportanddistributioninriceplantwereinvestigatedinhydroponicexperimentofmildCdpollutionwithexogenousZnaddition.Intheexperiment,Cdconcentrationswere0.01mg·L-1(lowdose),0.03mg·L-1(mediumdose),0.09mg·L-1(highdose),and0mg·L-1(control);andexogenousZnwere0.025mg·L-1,0.05mg·L-1,0.1mg·L-1,0.2mg·L-1.TheaimofthestudywastodeterminethemechanismofinteractionsbetweenZnandCdandtoidentifytheoptimalZnconcentrationthateffectivelyreducedCdpollutioninrice.TheresultsshowedthatbiomassesofdifferentpartsofriceplantincreasedsignificantlywithincreasingconcentrationofZn.Theincreaseofbiomasswashighestin0.05mg·L-1exogenousZntreatment.However,therewasnosignificantincreasewhenZnconcentrationexceeded0.05mg·L-1.Due to the low dose of Cd in the experiment, there was no significant variation in rice plant biomass with increasing CdconcentrationwithoutexogenousZn.UnderZn-freecondition,theratioofcytoplasmCdtocell-wallCdinricerootreducedfrom2.88to1.04withincreasingCdconcentration.WiththeapplyingofexogenousZn,theratioofcytoplasmCdtocell-wallCd showed increasing tendency, especially under 0.03 mg·L-1 Cd. Under medium-to-low Cd dose (0.01–0.03 mg·L-1), ZnsignificantlyinhibitedtheuptakeandtransportofCdinroot,whichsignificantlyreducedCdconcentrationinricecytoplasmandcellwall.ComparedwithZn-freetreatment,0.05mg·L-1ZnsignificantlyreducedCdcontentinrice.TheconcentrationofCdinplantroot,stemandleafreducedby38%,71%and65%underlow-doseCdandby44%,79%and69%undermedium-doseCd,respectively.TherateoftransportofCdbetweenrootsandstems,andbetweenrootsandleavesdecreasedby53%and44%underlow-doseCd,andby62%and40%undermedium-doseCd,respectively.WhenZnconcentrationexceeded0.05mg·L-1,therewasnoobviouschangeintheconcentrationofCdinroots,stemsandleavesalongwiththerateofCdtransportinrice.UnderhighconcentrationofCd(0.09mg·L-1),therewasnoobviousdeclineinCdconcentrationinroots,stemsandleavesduetoadditionofexogenousZn.AdditionofZnpromotedtheabsorptionofCdbyricestemandleaf.TherewasnoobviousantagonismbetweenZnandCdunderhighCdconcentration,althoughthesynergieswereobvious.Thusundermedium-to-lowdoseCdconditions,Zncontrolledthephyto-availabilityofCdduetoobviousantagonisticeffectsbetweenZnand Cd. Application of 0.05 mg·L-1 Zn significantly reduced Cd phyto-availability and migration in rice and maximallyincreasedplantbiomassunderlowconcentrationsofCdinhydroponiccultures.关键词
水稻/镉/锌/拮抗/镉迁移Key words
Rice/Cadmium/Zinc/Antagonism/Cadmiumtransfer分类
资源环境引用本文复制引用
曲荣辉,张曦,李合莲,马义兵..不同锌水平对低剂量镉在水稻中迁移能力的影响*[J].中国生态农业学报,2016,24(4):517-523,7.基金项目
国家科技部支撑计划项目(2015BAD05B01)和公益性环保行业专项(201509032)资助* ThestudywassupportedbytheNationalKeyTechnologiesR&DProgramofChina(No.2015BAD05B01)andtheSpecialFundforEnvironmentProtectionResearchinthePublicInterest(No.201509032). （2015BAD05B01）
