简介:氮使用效率(NUE)在中国是很低的,差不多70%应用的氮化肥的损失在high-yielding稻田被报导。以便调查高亲密关系的铵运输或举起的分子的基础进米饭(OryzasativaL.),我们分析了九铵的表示侧面transporters(AMT),OsAMT1的三各个,OsAMT2和OsAMT3,根据外部N地位在象在这些表示模式的变化一样的米饭生长的二个不同N要求阶段(年轻幼苗阶段和tillering阶段)使用即时反向的抄写聚合酶链反应(RT-PCR)。结果建议九OsAMT基因在米饭植物的不同机关被表示,包括成熟的根,新根,茎,旧叶子和新叶子并且表示模式是相应蛋白质的位置在种系发生的树上特定、独立的机关。OsAMT1;1,3;2和3;3在根和射击被表示,首先旧的叶子,OsAMT1;2和1;3主要在根,和OsAMT2;1,2;2,2;3和3;1主要在射击,首先在新叶子,并且相对更在里面茎比另外的基因。在二个不同N要求阶段的表示模式是一样;在有更大的N要求的tillering阶段,然而,OsAMTs抄本层次比在有低N要求的年轻幼苗阶段的那些大。为48h的N饥饿起来调整的OsAMT1;1,1;2,3;1,3;2,3;3并且下面调整的OsAMT1;3mRNA丰富。后面的N饥饿,NH4+和NH4NO3再供给下面调整的OsAMT1;2和3;3并且起来调整的OsAMT1;3,而NO3再供给下面调整的OsAMT1;1和1;2。这些建议OsAMT的器官特定的表示模式能被N要求和外部N地位调整。
简介:Aerobicstaticpilecomposting(mechanicalturningevery3days)ofpigmanurewaspreparedat8m3windrowheaps.Sawdustwasusedasthebulkingagenttoprovideadditionalcarbonandtoincreasetheporosityofthesubstrate.TwotreatmentsatinitialC/Nratiosof30and15,respectively,weredesignedinthestudy.Dissolvedorganiccarbon(DOC),solubleNH4+-N,C/Nratiosinsolidandaqueousphases,E4/E6ratios,andseedgerminationindex(GI)weredeterminedtoevaluatethematurityoftheco-composts.Seedgerminationindex,abiologicalparameter,wassuggestedasoneofthemostreliablematurityindicatorsfororganiccompost.TheresultsshowedthatthetreatmentattheinitialC/Nratioof30reachedmaturityafter49daysofcomposting;however,thetreatmentattheinitialC/Nratioof15shouldrequirecompostingtimeoflongerthan63daystoobtainmaturation.Chemicalmulti-indicatorevaluationwasnecessary,andtheGImeasurementwastherecommendedapproachformaturityevaluationinthestudy.
简介:温室条件下,向盆栽山毛榉幼苗中施加192g.m·^-2^15N示踪物,研究连续两个生长季沉积氮在森林土壤(含森林地被物)、沥出物、以及地上和地下部分生物量的分配。模拟了四种处理(栽培和非栽培)下的NH4^+和NO3^-沉积情况,每种处理各自标记为^15N-NH4^+或者^15N-NO3^-。在整个体系中施加15N的总回收率分别是,盆栽处理的^15N-NH4^+为67.3%~74.9%,非盆栽处理的^15N-NO3^-为85.3%~88.1%。两种^15N示踪物主要沉积在森林土壤(包括森林地被物)中,其中盆栽处理的森里土壤中^15N-NH4^+为34.6%~33.7%,^15N-NO3^-为13.1%~9.0%,说明异养微生物有很强的固氮作用。森林土壤微生物对^15N-NH4^+的固定能力比^15N-NO3^-的固定能力强三倍。^15N-NH4^+的优先异养利用造成土壤中^15N-NH4^+的沉积量是植物体保存量的两倍而土壤中^15N-NO3^-的沉积量却低于植物体的。总之,植被-土壤系统中15N-NH4+的沉积量比^15N-NO3^-的沉积高了60%,说明了沉积氮的形式在森林生态系统中氮保存中的重要性。
简介:FieldlysimetermethodwasemployedtoinvestigatethedownwardmovementandleachingofNappliedtosummercorn(ZeamayL.)ondrylandsoilinBeijing,AN-fertilizer(120kgNhm^-2)andacontroltreatmentwerarrangedforthestudy.Soilsolutionwascollectedatdepthsof20,40,60,120and170cm,whileleachtewasollectedatthebottom(220cm)ofthelysimeter,TheresultsshowedthatthedownwardmovementofNO3^-Ninsoilprofilewasgreatlyaffectedbyrainfallpattern.ThepeakofleachedNO3^-Nfrombothtreatmentscoincidedwiththepeakoftherainfall.Inaddition,leachedNO3^-Nfrombothtreatmentsandrainfallweresignificantlycorrelated(P<0.05).TheamountofleachedNO3^-NwasnotgreatintheN-fertilizertreatment,TheresultsalsosuggestedthatNfertilizationcouldcauseNO3^--Ncontaminationofgroundeaterduringtherainyseason.
简介:测定了6个N-硝基二苯基脲衍生物(Ⅰ)在500mg/L浓度下对稗草Echinochloacrusgalli和绿苋Amaranthusviridis的除草活性,从中筛选出两个化合物Ⅰb、Ⅰe做系列浓度试验.结果表明,它们对稗草、绿苋均表现出一定的抑制活性,且随着浓度增加,抑制活性增强.
简介:Nitrogenousfertilisersareunderconsiderationforpromotingthegrowthofnursery-rearedhooppine(AraucariacunninghamiiAitonexA.Cunn)seedlingsintheestablishmentphaseofsecondrotation(2R)plantations.Using15N-labelledfertilisers,weinvestigatedtheeffectofdifferentforms(ammoniumsulphate,ammoniumnitrate,potassiumnitrateandurea)andratesofapplication(0,150and300mgNkg-1driedsoil)offertilisersonthegrowth,15Nrecoveryandcarbonisotopecomposition(δ13C)ofhooppineseedlingsina12-monthglasshousetrialinsoutheastQueensland,Australia.The15N-labelledfertiliserswereappliedtonursery-rearedhooppineseedlings,whichwerethengrowninpots,containingca.1.2kgdriedsoil,underwellwateredconditionsfor12months.Fourseedlingsfromeachtreatmentwereharvestedat4-monthintervals,dividedintoroots,stemandfoliage,withafurthersubdivisionfornewandoldfoliage,andthenanalysedfor15N,totalN,δ13CandtotalC.Therewasnosignificantresponseintheseedlinggrowthtotheformorrateofapplicationofnitrogen(N)fertiliserwithinthe12-monthperiod,indicatingthattheseedlingsdidnotexperienceNdeficiencywhengrownonsecondrotationhooppinesoils.Whilethecombined15Nrecoveryfromsoilandplantremainedataround70%throughouttheexperiment,theproportionof15Nrecoveredfromtheplantsincreasingsteadilyovertime.Nitratecontainingfertilisersat150mgNkg-1soilgraduallyincreasedseedlingfoliageδ13Coverthe12-monthperiod,indicatinganincreaseinseedlingwateruseefficiency.
简介:Natural^15NabundancemethodwasusedinthisstudytoinvestigatetheN2-fiingcapacitiesofseveralherbaceousandshrublegumesbyafieldexperiment,Forherbaceouslegumes,theresultswereinconsistentwiththoseobtainedbyapotexperiment.CrotalariamucronataDesv.hadahigher,N2-fixingcapacitythanVignasinensis(L.)Savi.Forshurublegumes,N2-fixingCapacityunderfieldconditionwasslightlydifferentfromthatinpotexperiment.Theseresultsdemonstratedthatthenatural^15NabundancemethodwasapplicabletoevaluatingN2-fixingcapacitiesofherbaceousandshrublegumes,andthatpotexperimentwassuitableforevaluatingtheN2-fixingcapacitiesofnotonlyherbaceouslegumesbutalsoshrublegumes.LeguminousN2-fixingplantsdifferedinresponsetophosphorusfertilization,Phosphorusfertilizerappicationgreatlyincreasedthepercentageofnitrogenderivedfromair(%Ndfa)andtotalamountofN2fixedbyLespedezformosa(Vog.)Koehne(Jiangxi),PhosphorusfertilizershowednosignifcanteffectontheN2-fixingpercentageofCajanuscajan(L.)Millsp.butincreaseditstotalbiomass,thusincreasingthetotalamountofN2fixed.
简介:Theeffectsofsimulatednitrogen(N)depositiononsoilexchangeablecationswerestudiedinthreeforesttypesofsubtropicalChina.FourNtreatmentswiththreereplicationsweredesignedforthemonsoonevergreenbroadleafforest(matureforest):control(0kgNha-1year-1),lowN(50kgNha-1year-1),mediumN(100kgNha-1year-1)andhighN(150kgNha-1year-1),andonlythreetreatments(i.e.,control,lowN,mediumN)wereestablishedforthepineandmixedforests.Nitrogenhadbeenappliedcontinuouslyfor26monthsbeforethemeasurement.ThematureforestrespondedmorerapidlyandintensivelytoNadditionsthanthepineandmixedforests,andexhibitedsomesignificantnegativesymptoms,e.g.,soilacidification,Almobilizationandleachingofbasecationsfromsoil.ThepineandmixedforestsrespondedslowlytoNadditionsandexhibitednosignificantresponseofsoilcations.ResponseofsoilexchangeablecationstoNdepositionvariedintheforestsofsubtropicalChina,dependingonsoilNstatusandland-usehistory.
简介:高温(〉28℃)可引起含N基因的免疫寄主对TMV抗性丧失,导致TMV系统侵染。本研究以枯斑三生(Nicotianatabacumvar.SamsunNN)烟草为研究材料,采用代谢组学方法,系统研究25℃和31℃条件下,TMV未侵染和TMV侵染12h、24h和48h枯斑三生烟草的代谢差异。应用气相色谱与质谱联用(GC-MS)技术,结合主成分分析(PCA)和正交偏最小二乘-判别分析法(OPLS-DA)对不同温度下代谢产物的差异性进行分析。结果表明:GC-MS技术共检测到49种代谢物包括氨基酸类、糖类、有机酸类、脂肪酸类、醇类以及多胺类等。在25℃常温条件下,TMV侵染枯斑三生烟引起苹果酸、水杨酸、γ-氨基丁酸、脯氨酸和乙醇胺等代谢物含量上调,而在31℃高温处理N基因失活后,TMV侵染导致组织蔗糖和肌醇含量下调、葡萄糖和果糖含量上调以及伴随氨基酸类含量普遍上调。
简介:AfieldexperimentwasconductedonChinesecabbage(BrassicacampestrisL.ssp.pekinensis(Lour.)Olsson)inaNanjingsuburbin2003.Theexperimentincluded4treatmentsinarandomizedcompleteblockdesignwith3replicates:zerochemicalfertilizerN(CK);ureaatratesof300kgNha-1(U300)and600kgNha-1(U600),bothasbasalandtwotopdressings;andpolymer-coatedureaatarateof180kgNha-1(PCU180)asabasalapplication.Theacetyleneinhibitiontechniquewasusedtomeasuredenitrification(N2+N2O)fromintactsoilcoresandN2Oemissionsintheabsenceofacetylene.ResultsshowedthatcomparedtoCKtotaldenitrificationlossesweresignificantlygreater(P≤0.05)inthePCU180,U300,andU600treatments,whileN2OemissionsintheU300andU600treatmentsweresignificantlyhigher(P≤0.05)thanCK.IntheU300andU600treatmentspeaksofdenitrificationandN2OemissionwereusuallyobservedafterNapplication.Inthepolymer-coatedureatreatment(PCU180)duringtheperiod20to40daysaftertransplanting,higherdenitrificationratesandN2Ofluxesoccurred.Comparedwithurea,polymer-coatedureadidnotshowanyeffectonreducingdenitrificationlossesandN2OemissionsintermsofpercentageofappliedN.Astemperaturegraduallydecreasedfromtransplantingtoharvest,denitrificationratesandN2Oemissionstendedtodecrease.Asignificant(P≤0.01)positivecorrelationoccurredbetweendenitrification(r=0.872)orN2Oemission(r=0.781)fluxdensitiesandsoiltemperatureintheCKtreatmentwithastablenitratecontentduringthewholegrowingseason.
简介:polyolefin涂的脲的有效性(Meister-5和Meister-10;CU)在小麦(TriticumaestivumL.)玉米(ZeamaysL.)旋转系统在为收割季节的三连续maize-wheat-maize位于北方中国平原的溶度计阴谋被学习。一个同位素的方法被用来把CU的命运比作非涂的脲(NCU)的,并且N申请0,100,150和225kgNha−1评价被评估。结果证明CU的氮使用效率(15NUE)是比为第一庄稼的NCU的大的13.3%–21.4%。或者,当差别方法被使用时(明显的NUE),没有重要变化在所有三个季节在处理之中被观察。尽管无机的N从1.3m层沥滤,不到1%总数被使用N,15N的未辩别出的损失(=15N作为化肥–15N使用了的15N的损失由留在0–0.2m层–15N的庄稼–15N吸收了从1.3m层沥滤)在对待CU的阴谋是24.2%–26.5%比那些低对待NCU的阴谋。在在实验的结束的CU阴谋的0–1.3m层的硝酸盐集中是53%比对待NCU的阴谋的低。因此,CU从化肥增加了庄稼N举起并且减少了应用N的未辩别出的损失,它能减少地下水污染的风险。
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.