简介：DNAisthegeneticmaterialofvariousorganisms.ExtracellularDNAadsorbedorboundonsurface-activeparticlesinsoilshasbeenshowntopersistforlongperiodsagainstnucleasesdegradationandstillretaintheabilitytotransformcompetentcells.ThispaperreviewssomerecentadvancesonthebindingandtransformationofextracellularDNAinsoils,whichisfundamentaltounderstandingthenatureofthesoil,regulatingbiodiversity,andassessingtheriskofreleasinggeneticallyengineeredmicroorganisms(GEMs)aswellasbeinghelpfulfordevelopmentofthegeneticevolutionaltheoryofbacteria.Severalinfluencingfactors,suchassoilpH,ionicstrength,soilsurfaceproperties,andcharacteristicsoftheDNApolymer,arediscussed.Todate,theunderstandingofthetypeofmolecularbindingsitesandtheconformationofadsorbedandboundDNAtosoilparticlesisstillinitsinfancy.

简介：Anewinorganicphosphorus(IP)fractionationschemedevelopedbyJiangandGuwasusedinanincubationexperimenttoinvestigatethetransformationofappliedPinacalcareousfluvisol.Theresultsshowthatafteradditionofcommonsuperphosphate(CSP),theCa2-PinthesoildecreasedgraduallyandtransformedlargelytothelessavailableFe-P,Al-PandCa8-P,ratherthantotheunavailableformsofCa10-PandO-P.ThedifferentIPfractionsrankedinthefollowingorderwithrespecttotheincrementbyadditionofCSPafter120daysofincubation:Fe-P>Al-P>Ca8-P>Ca2-P.Afteradditionofpigmanure,thecontentofCa2-Pinthesoilincreasedrapidlyatfirstandthendecreasedslowly,andtheamountofdifferentIPfractionsaccumulatedafter120daysofincubationrankedinthefollowingorder:Ca2-P>Fe-P>Ca8-P>Al-P.Evidently,thevariationincontentofCa2-PandtheorderofincreaseindifferentIPfractionsinincubationinducedbyapplicationofpigmanurewerequitedifferentfromthatofCSP.TheincreaseinIPfractionsintheincubationofbroadbeangreenmanure(BBGM)for120dayswasintherankofFe-P>Ca2-P>Ca8-P;butbecauseorganicphosphorus(OP)ofBBGMdegradedrelativelyslowly,theincrementinIPfractionswaslowerthanthatofpigmanure.WheatstrawwasdifficulttomineralizeandinducedastrongbiologicalfixationofsoilP,resultinginadecreaseofthecontentofCa2-P,evenCa8-P,Fe-PandAl-P.

简介：TheeconomictransformationinChinahascausedsignificantchangestolaborrelations.Ithasmadethelaborrelationsmorecomplexandlaborconflictsapparentandfrequent.Howeverthecoordinationmechanismhasnotbeendevelopedcorrespondingly.Basedontheempiricalresearchuponcurrentdomesticandoverseaslaborrelations,itisconcludedthatthesupplyoflaborforceexceedingthedemandofitisthefundamentalreasonsforexplaininglaborconflictsintheeconomictransformationinChina.Italsosuggestedthatthecoordinationmechanismoflaborconflictshasmechanicaldysfunctionandthestructureofharmoniclaborrelationswouldtakealongtime.

简介：与木头纤维素合成联系的UGPase基因被变成C。用调停Agrobacterium的遗传转化的方法的acuminata，；一个有效转变系统为C被开发。根据几的评估，影响调停Agrobacterium的脱氧核糖核酸转移的因素评估的acuminata。当pre有教养的叶将生物的活组织移植于培养基中培养为10min感染相应于OD600(0.5)的一种Agrobacterium文化时，最高的转变率被完成，；在三天的将生物的活组织移植于培养基中培养新生媒介上有教养。南部的杂交的结果证明到一根UGPase基因探针的kanamycin抵抗的射击的genomic脱氧核糖核酸证实了transgene的集成。转变效率(6%)在优化转变过程下面被完成。这个系统应该便于重要有用基因的介绍进C。acuminata。

简介：Sulfurtransformationin3soilsmaintainedinaclosedincubationsystemanditsavailabilitytoplantswereinvestigatedusingcarrier-free^35S-SO4^2-and^35S-labeledryegrassstraw.Forcarrier-freeNa2^35SO4treatment,78%,70%and64%of^35SappliedwerefoundinCa(H2PO4)2-extractaleSfraction,4%,5%and7%inslowlysolubleinorganicS,11%,15%and18%inC-O-S,5%,7%,and6%inC-bondedS,and5%,7%and6%inunidentifiedorganicS120daysafterincubationinblacksoil,cinnamonsoilandchestnutsoil,respectively.Mostof35Suptakebyplantscamefromextractable35SO4^2-,andlittlefromC-O-^35SandC-bonded^35S,Inthetreatmentwith35S-labeledstraw,51%,46%and36%of35SincorporatedwerefoundinCa(H2PO4)2-extractableSfraction,7%,6%and7%inslowlysolubleinorganicS,13%,15%and18%inC-O-S,8%,8%and6%inC-bondedS,and18%,25%and35%inunidentifiedorganicSattheendofincubationinabove-mentonedthreesoils,respectively.HigheravailabilityofC-O-35S,C-bonded35Sandunidentifiedorganic35Sfrom35S-labeledstrawwasobservedin35S-labeledstrawtreatmentcomparedtocarrier-freeNa2^35SO4treatment.

简介：泥土矿物质捱过是到植物的营养素的来源。Palygorskite是通常发生在干旱区域的土壤和沉积的一种Mg富有的含纤维的泥土矿物质。尽管许多研究检验了为palygorskite的形成和稳定性要求的环境条件，在根地区的这种矿物质的转变的信息(或根围)农业庄稼被限制。这研究在小麦和燕麦的根围探索了palygorskite转变的可能性并且比较了这些庄稼的能力从palygorskite提取结构的Mg。庄稼在从Hamadan区域，伊朗和佛罗里达palygorskite由沙的混合物组成的壶被栽培，与提取的水灌溉了，并且与完全或Mg免费的滋养的答案对待。在100d以后，由庄稼的Mg举起被测量。在每个壶的泥土大小的粒子也与沙被分开并且通过X光检查衍射(XRD)被分析。粒子的X光检查模式与纯palygorskite粒子的相比(在耕作前)。结果证明palygorskite能在与Mg免费的滋养的答案供应的壶为小麦的生长提供足够的Mg。尽管有由从palygorskite结构的两植物的镁举起，显示palygorskite的转变的可检测的山峰都没被XRD认出。在山峰紧张的1.05nm的减少为包含palygorskite的壶是更明显的并且比为与完全的滋养的答案灌溉的壶与Mg免费的滋养的答案灌溉了。尽管在山峰紧张的减少比小麦为燕麦是更大的，显示由燕麦捱过的更大的palygorskite，由燕麦的Mg举起是低的由观察的缺乏症状证实了。

简介：SeveralimportantfactorsaffectingtheefficiencyofAgrobacterium-mediatedricetransformationwerestudiedwithseveralpredominantcommercialindicaandjaponicaricecultivars.Asfarasindicaricecalluswasconcerned,CCmediumwasthebestandthequalityofcalluswasimprovedwiththeadditionof1.0to2.0mg/LABA.Itdecreasedthepercentageofbrowningcalliandimprovedthecallusgrowingstatebyadditionofacertainamountofsorbitoltothesubculturemedium.NBmediumwasthebestforcallusinitiationofjaponicarice,buttheimprovementinthequalityofcallusofjaponicasubspecieswasnotobviousbyaddingABA.Duringtheperiodofsubculture,toacertaindegree,increasingthesucroseconcentrationcouldimprovetheproportionofhygromycinresistantcalli.Furthermore,thetransformationefficiencywouldbehigherbyapplyingselectionpressureintheselectionstage,removingselectionpressureduringtheplantletdifferentiationperiodandapplyingselectionpressureagainduringseedlinghardeningperiod.Besides,suitablecombinationofplanthormoneswasbeneficialforcallusdifferentiation.AnefficientAgrobacterium-mediatedricetransformationsystemhadbeenestablishedforseveralricecultivarsandalotoftransgenicriceplantshadbeenobtained.

简介：Athermostaticincubationexperimentwascarriedouttoestimatetheeffectsoffloodingperiods,stalkapplicationandPadditionofFetransformationandPavailabilityincalcareoussoils.SubmergenceincreasedamorphousFe,especiallyinthecaseofstalkapplication.ThenewlyformedamorphousFewithagreatsurfaceareaplayedanimportantroleinPsorption;andsubmergencealsostimulatedthedissolutionofinorganicP,thusincreasingtheavailabilityofsoilPincalcareoussoils.Meanwhile,apartofsolublePwasabsorbedandfixedagainonthesurfaceofnewlyformedamorphousFe,thusresultinginadecreaseofPavailability.SoilrapidlyavailablePincreasedafter150-dayincubation.ThereexistedsignificantlynegativecorrelationsbetweensoilamorphousFecontentandsoilFe-PandrapidlyavailablePcontents.SubmergedconditionspromotedthetransformationofinorganicPaddedtowardFe-Pincalcareoussoils,especiallyinthecaseofstalkapplication.

简介：InteractionsofN,PandKfertilizersinsoil-plantsystemsarewidelyrecognized.Thisstudyfocusedonthetransformationsofmonocalciumphosphate(Ca(H2PO4)2)(MCP)withco-applicationofammoniumandpotassiumfertilizersinthreedifferentsoils.Theresultsshowedthatafter1dincubationalargeportionoftheMCPappliedinthepaddy,calcareousandredsoilsbecamethewater-insolubleformandtherecoveriesofPappliedasOlsenPvariedgreatlyinthesethreesoils.Applicationofammoniumsulfate((NH4)2SO4)(AS)orpotassiumchloride(KC1)reducedWSPsignificantlyinthesoilswithASmoreeffectivethanKC1inthecalcareoussoil,whilethereverseoccurredintheredsoil.Meanwhile,inthepaddysoil,co-applicationofthetwofertilizersreducedWSPmorethanwhenthefertilizerswereappliedindividually.Theco-applicationofASwithMCPinthepaddyandcalcareoussoilssignificantlyreducedOlsenP,buttheoppositeoccurredintheredsoil.Theexperimentontheeffectofdifferentaccompanyinganionsshowedthattheammoniumfertilizers(PNC1andPNS)reducedWSPmoreeffectivelythanthecorrespondingpotassiumfertilizers(PKC1andPKS)inthecalcareoussoilduetothedifferenceofthecations,whereasintheredsoil,thechloridesreducedWSPmoreeffectivelythanthesulfates.Overall,co-applicationofammoniumorpotassiumfertilizerswithMCPsignificantlydecreasedavailabilityofPfromMCPduringitstransformationinsoils,especiallywhenMCPwasappliedincombinationwithammoniuminthecalcareoussoil.

简介：ThedistributionandtransformationofaddedandnativeNiinpurplesoilswereinvestigatedwithbothsequentialextractionprocedureandisotopictracertechnique.ThedistributionofaddedandnativeNiwasgreatlydependentonsoilproperties.LowsoilpHwasfavorableforsolubleplusexchangeable(EX)Fraction,whileFe/MnoxidesandclayforFe/Mnoxidebound(OX)andresidual(RES)fractions.TheaddedNi,however,hasnotyetreachedthedistributionequilibriumuptothe150thdayafterincubation.ThiswasreflectedinthefactthattheproportionofEXfractionfromaddedNiwas150%-600%asmuchasthatofnativeNi,whilethatofRESfractionwasonlyabout80%,Onceenteringsoil,theappliedsolubleNiwasrapidlytransformedintootherfractions,buttheorganiccomplexe(OM)fractionofaddedNiwasrelativelystableduringincubation.Thecarbonatebound(CAB)fractionshowedaprogressiveincreaseandattainedapeakvalueafter0-14dofincubationandthereafterdecreasedgradually.TheoccurrencetimeofthispeakadvancedasinitialsoilpHincreased.butthepeakwoulddisappearwheninitialsoilpHwashigherthan7.5(orcontainingfreeCaCO3).ThetransformationprocessesoftheEX,OXandRESfractionscouldbedescribedbyElovichandtwo-constantrateequations,andtheratewerepositivelycorrelatedwithsoilpH,CECandclay.ThesefindingcouldexplainwhytherearedifferencesinecologicalandenvironmentaleffectsofNiindifferentsoilsandatvariousintervals.

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简介：Threegoatswerefedwith^15N-labelledricestrawtostudythecharacteristicsofdigestion,assimilation,transformationandexcretionofCandNcompoundsfromricestraw.Itwasshownthattheamountof^15Ntransformedintothebodiesofthetwoslaughteredgoatsaccountedfor38.5and23.6%ofthetotalamountof^15Ndepositionoftheexperimentaldiettakenbyeachgoat.The^15Nexcretedthroughthefecesandurineforthethreegoatsaccountedfor34.8,33.2and33.9%ofthetotalamountof^15Ndepositioninthefeedofthe3goats.Therecoveryoftotal^15Nforthetwoslaughteredgoatswere73.3and57.5%,withthecorrespondingratesof^15Nloss26.7and42.5%respectively.ThedigestibilitiesoftotalaminoacidsforGoats1and3were68.7and54.0%,andthedigestibiltiesofcarbohydratesforthetwogoatswere74.8and67.7%respectively.

简介：Soilnitrogenpools(NP),denitrification(DN),grossnitrification(GN),N2OandCO2fluxrateswiththeirresponsestotemperatureincreasesweredeterminedunderfivedifferentlandusesandmanagementsinasubalpineforest-grasslandecotoneoftheeasternTibetanPlateau.Landusesconsistedof1)sparsewoodland,2)shrub-land,3)naturalpasture,4)fencedpasture,and5)tilledpasturemimickingagradientdegeneratingecosystemundergrazingimpacts.TheNO3--NcontentwashigherthantheNH4+-Ncontent.Comparingtilledpasturewithfencedpastureshowedthathigherintensivemanagement(tillage)ledtoasignificantdecreaseofsoilorganicmatter(SOM)(P＜0.05)inthesoils,whichwasincontrasttothesignificantincreases(P＜0.05)ofDN,GN,N2OandCO2fluxrates.GN(excludingtilledpasture)andCO2fluxratesincreasedwithatemperaturerise,butDNandN2Ofluxratesnormallyreachedtheirmaximumvaluesat12-14℃withtilledpasture(thehighestmanagementintensity)beingverysensitivetotemperatureincreases.TherewasadifferencebetweennetnitrificationandGN,withGNbeingabetterindicatorofsoilnitrification.

简介：土壤drying-rewetting(DRW)事件影响滋养的转变和微生物引起的社区作文；然而，很少对在DRW事件期间弄干紧张的影响被知道。因此，我们在一个试验性的drying-rewetting事件期间与暴露分析了土壤营养素作文和微生物引起的社区到各种各样的弄干的紧张，用从北中国的一块草地的淤泥沃土，在半干旱的气候暴露土壤到大量潮湿条件的地方，并且草地占超过40%国家陆地区域。我们也进行了一个消毒实验检验土壤微生物的贡献到滋养的脉搏。土壤drying-rewetting减少了由9%-27%的碳(C)矿化作用。monosaccharide和矿物质氮(N)内容与更高弄干紧张增加了(弄干到10%gravimetric水内容)，与最高的弄干紧张随增加是204%和110%(弄干到2%gravimetric水内容)，分别地而易变的磷(P)仅仅增加了(在105%)与最高的弄干紧张。而且，微生物引起的生物资源C和N和溶解器官的N的层次与增加弄干紧张减少了并且分别地，而易变的P的增加不与在微生物引起的生物资源P的减小一致，随溶解器官的C和矿物质N的增加被相关。消毒实验结果显示微生物为C和N脉搏主要负责，而非微生物引起的因素是到易变的P脉搏的主要贡献者。Phospholipid丰满的酸分析显示土壤微生物对drying-rewetting事件高度抵抗并且干旱抵抗的组为滋养的转变可能负责。因此，现在的学习证明在drying-rewetting事件期间弄干的中等土壤能改进N，然而并非P的矿化作用，并且不同机制为C，N，和P脉搏负责，这在drying-rewetting期间观察了事件。

简介：Thecalcareousfluvo-aquicsoilwascollectedandamicrocosmstudywascarriedoutwithroot-matandfrozenslicingmethodinlaboratory.ThepHintheroot-soilinterfacewiththecontroltreatmentwasjustslightlylowerthaninthebulksoil.However,theadditionofNH4--NsignificantlydecreasedthepHvalueintheroot-soilinterfaceandtheadditionofNo3-NslightlyincreasedthepHvalueintheroot-soilinterface.ThemagnitudeofpHchangesintheroot-soilinterfacedependedupontheconcentrationsofthenitrogensourcesadded.ThecontentsofCa2-P,Fe-PandAl-Pintheroot-soilinterfaceweremuchloweraftertreatedwithNH4-NandslightlyhigheraftertreatedwithNo3-Ncomparedwithcontroltreatment.Aftertreatedwith100,200and400mg·kg-1NH4+-N,thedeficiencyratesofCa2-Pinthearea0-1mmfromtherootplanewere37.1%,45.9%and57.7%,respectively,thedeficiencyratesofFe-Pwere23.4%,29.1%and38.2%,respectively,andthedeficiencyratesofAl-Pwere25.1%,28.0%and33.2%,respectively.ComparedwiththecontrolthedeficiencyratesofCa8-PinNH4+-NandNo3-Ntreatmentsdecreasedandincreased,respectively,butthedifferenceswerenotobvious.ThecontentsofCa10-PandO-Pintheroot-soilinterfacedidnotsignificantlychangeaftertreatedwithNH4+-NorNo3-N,suggestingthatCa10-PandO-PwereremarkablydifficulttobemobilizedevenatthepresenceofhighconcentrationofNH4+-N.TheloweredpHintheroot-soilinterfaceinducedbytheadditionoftheNH4-Npromotedthetransformationofphosphatesintheroot-soilinterface,enhancedthemobilizationandbioavailabilityofphosphates,andtherebyremarkablyincreasedtheabsorptionofphosphorusbyroots.

简介：Elevatedatmosphericnitrogen(N)depositionhasbeendetectedinmanyregionsofChina,butitseffectsonsoilNtransformationintemperateforestecosystemsarenotwellknown.WethereforesimulatedNdepositionwithfourlevelsofNadditionrate(N0,N30,N60,andN120)for6yearsinanold-growthtemperateforestinXiaoxing’anMountainsinNortheasternChina.WemeasuredgrossNtransformationratesinthelaboratoryusing15NtracingtechnologytoexploretheeffectsofNdepositiononsoilgrossNtransformationstakingadvantageofNdepositionsoils.NosignificantdifferencesingrosssoilNtransformationrateswereobservedafter6yearsofNdepositionwithvariouslevelsofNadditionrate.ForallNdepositionsoils,thegrossNH4+immobilizationrateswereconsistentlylowerthanthegrossNmineralizationrates,leadingtonetNmineralization.Nitrate(NO3-)wasprimarilyproducedviaoxidationofNH4+(i.e.,autotrophicnitrification),whereasoxidationoforganicN(i.e.,heterotrophicnitrification)wasnegligible.Differencesbetweenthequantityofammonia-oxidizingbacteriaandammonia-oxidizingarchaeawerenotsignificantforanytreatment,whichlikelyexplainsthelackofasignificanteffectongrossnitrificationrates.GrossnitrificationratesweremuchhigherthanthetotalNO3-consumptionrates,resultinginabuild-upofNO3-,whichhighlightsthehighriskofNlossesviaNO3-leachingorgaseousNemissionsfromsoils.ThisresponseisoppositethatoftypicalN-limitedtemperateforestssufferingfromNdeposition,suggestingthattheinvestigatedold-growthtemperateforestecosystemislikelytoapproachNsaturation.

简介：ToconstructtheT-DNAinsertionalmutagenesistransformationsystemforricesheathblightpathogenRhizoctoniasolaniAG-1IA,thevirulentisolateGD118ofthispathogenwasselectedasaninitialisolatefortransformation.TheconditionsfortransformationofisolateGD118wereoptimizedinfiveaspects,i.e.pre-inductiontime,co-culturetime,acetosyringone(AS)concentrationattheco-culturephase,co-culturetemperatureandpHvalueofinductionsolidmedium(ISM)attheco-culturephase.Finally,asystem...

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