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ID:32276146
大小:5.33 MB
页数:67页
时间:2019-02-02
《硅、硫对水稻砷吸收、积累的影响机制的的研究》由会员上传分享,免费在线阅读,更多相关内容在学术论文-天天文库。
1、常青晓:硅、硫对水稻砷吸收、积累的影响机制研究盐处理的水稻根部主要形态是砷酸盐外,其它处理后水稻植株中砷的形态均为Ⅱ砷酸盐。在亚砷酸盐处理中,并且低硫预处理的水稻根系中亚砷酸盐积累量低于高硫预处理,但低硫预处理的水稻地上部中Ⅱ砷酸盐浓度显著高于高硫预处理的水稻地上部。在砷酸盐处理中,低硫预处理使根系砷积累显若降低。与高硫处理相比,低硫预处理植株的砷转运系数较高。除此之外,营养液中硫素不足使砷胁迫下水稻根系中非蛋白巯基的浓度降低。这些结果说明水稻根系积累的砷人都以亚砷酸盐的形态存在,且硫素状况直接影响到砷从根系向地上部的转运,这可能与Ⅱ砷酸盐和植物螯
2、合肽形成络合物有关。(3)水稻植物螯合肽合成酶(PCS)基因的克隆及植物表达载体的构建利用RT-PCR方法从水稻总RNA中经反转录克隆出植物螯合肽合成酶(phytochclatinsynthase,PCS)基因。通过序列分析发现该基因是位于水稻的第6号染色体上,并且与已经登陆的水稻(Oryzasativa)NM001063069.1核苷酸序列同源性最高,而与高粱、玉米的亲缘关系较远。同时,为进一步研究PCS的理化性质及生物功能,利用pET-28a、pCam2335分别构建了该基冈的原核表达载体和菲特异性表达载体。关键词:水稻,砷,硅,硫,植物螯合肽
3、,基因克隆2河南农业大学硕士学位答辩论文英文摘要ResearchonlnflunceofSiliconandSulfuronArsenicUptakeandAccumulationofRice(OryzasativaL.)Supervisor:Prof.ZhaoQuanZhi,Author:ChangQingXiaoABSTRACT:Withthecontinuingdevelopmentofindustrialtechnology,moreandmorepeoplearebecomingtoconcelTlthesocialandenvironm
4、entalproblemswhichduetotheheavymetalpollution.Arsenicisawidespreadenvironmentalcontaminant.Nowadays,ChinahasbecomeoneofthemostseriouscontaminationcountriesinthelistofWorldHealthOrganization(WHO).What’Smore,thehealthriskofarsenicinhumanbeingsthroughf.ood—chainisbecomingworse.Th
5、erefore,seekinganeffectivemethodforreducingthearsenicrisktohumanhealththroughfoodchainisimminent.Ontheonehand,RiceisoneofChina’Sthreemajorfoodcrops,whichisalsoatypicalcropofsilicon.Siliconcanpromotericegrowthandhighyield,besidesitcansignificantlyreducearsenateandarseniteuptake
6、byrice.Ontheotherhand,theformationofPCsinresponsetothestresscausedbyheavymetalswasoneofthetrulyadaptiveresponsesoccurredcommonlyinhigherplants.Sulfurisanimportantcomponentofficeproteinandphytochelatins(PCs).Whatisthepossiblemechanismofsulfuraffectingarsenicabsorptionbyrice?The
7、researchaboutthisfieldisnotmuchathomeandabroad,whichisthemainresearchinthisissues.Hydroponicexperimentandpotexperimentwereconductedtostudythedifferencesandmechanismsaboutarsenicuptakeandaccumulationamongfourricegenotypes,inwhichricecultivarsTN1andBaixiangiingwithhighsiliconupt
8、akeefficiencyandJuanyejingandHitomeborewithlowsiliconefficien
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