J.LakeSci.2014261131-136http//.jlakes.org.E-mailjlakes@niglas.ac.cn2014byJournalofLakeSciencesAphanizomenonflos-aquae*1211311**143007221000493430010Aphanizomenonflos-aquae..0.5mg/L.BG-113d50%72%.7d43d30mg/L.PhysiologicalresponsetolownitrogenlevelinAphanizomenonflos-aquaefromLakeDi-anchiWUYanlong12ZHENGLingling1LILin1YINDacong3DAIGongyuan1&SONGLirong11StateKeyLaboratoryofFreshwaterEcologyandBiotechnologyInstituteofHydrobiologyChineseAcademyofSciencesWuhan430072P.R.China2UniversityofChineseAcademyofSciencesBeijing100049P.R.China3WaterResourcesDepartmentYangtzeRiverScientificResearchInstituteWuhan430010P.R.ChinaAbstractTwostrainsofAphanizomenonflos-aquaewereisolatedfromspringcyanobacterialbloomsinHaigengBaywhichlocatedinthenorthernpartofLakeDianchi.BoththegrowthcharacteristicsandheterocystformationaswellasnitrogenfixationabilityofA.flos-aquaewereinvestigatedunderdifferentlowconcentrationsofsodiumnitrateandinnitrogen-freeculturemediumrespective-ly.TheresultsshowedthatA.flos-aquaestrainswereabletogrowintheBG-11mediumwithvariouslowconcentrationsofnitrateandthebiomassreachedaveryhighlevel.Thebiomassincreasedwiththenitrate-nitrogenconcentrationincreasingbuttherewasnosignificantdifferencewhennitrate-nitrogenconcentrationwasabove0.5mg/L.InductionofheterocystdifferentiationwasrapidwhenA.flos-aquaewasculturedinN-deficientBG-11mediumandafterreachingamaximumof72%approximatelythefilamentwithheterocystbegantoswinglower.Thetotalnitrogeninnitrogen-freemediumincreasedgraduallyasnitrogenfixationproceedandnitrogenconcentrationwascloseto30mg/Latday43.KeywordsLakeDianchiAphanizomenonflos-aquaenitrate-nitrogenheterocystnitrogenfixation1.、Microcystis2.***NSFCU-0833604、2013ZX07102-00551279011.2013-02-252013-04-22.1984~E-mailljf19841113@163.com.E-maillrsong@ihb.ac.cn.132J.LakeSci.2014261Aphanizomenonflos-aquae、、3-6..1982121983147.198167.73×107cells/L98%“”8.1998340.5m9.2002———4m10.2001200911-12.、、、、、、4613-15.、16-20.、、.、..11.1Aph120104Aph920113.1L30ml50ml.OlympusCX315CT213CT12.20±1℃、12h∶12h、20μE/m2·s.1150mlCT..24°56'43″N102°38'55″E15.1±0.36℃、pH8.92±0.42、7.65±0.14mg/L、28.5±2.0cm、a121.2±39.6μg/L、0.027±0.009mg/L、0.037±0.010mg/L、0.332±0.056mg/L、2.933±0.178mg/L、4.360±1.594mg/L.1.2CT.3BG-1122、20±1℃、12h∶12h、30μE/m2·s..90011001800680nm.OlympusCX31..1.3pH、YSI550AYSIUSA23.1+948h.Aphanizomenonflos-aquae1331.4Origin8.0SPSS18.0One-wayANOVAP<0.05.22.1Aph1Aph90、0.5、2、5、10、20mg/LBG-11274mg/LBG-110.1...Aph140d680nm1.35420、10、52mg/L45dBG-11P>0.050.5mg/LP<0.05.0.9.Aph1Aph945dP<0.05.1Fig.1Theeffectsofdifferentnitrate-nitrogenconcentrationsonthegrowthofA.flos-aquaeisolatedfromLakeDianchi2Fig.2HeterocystcharacteristicsofA.flos-aquaeinducedinN-freestatus2.2.Aph93d50%7d72%.Aph1Aph950%.BG-1110d2.3134J.LakeSci.20142613Aph9Fig.3LightmicroscopeofheterocystformationatdifferentstagesandautofluorescenceofA.flos-aquaestrainAph94Fig.4NitrogenfixationcharacteristicsofthetwostrainsofA.flos-aquae.Aph93A~DBG-113E.Aph93F.2.3Aph1、Aph9.4.1Aphanizomenonflos-aquae1357d..25mg/L.3、aDNA.a2425-26.160、、、、..NH3α-Ca2+.N2NH3NH3-27-29.BG-113d50%.BG-110.5mg/LBG-11.0.5mg/L.30.Schindler31-34、、、30.、、35.30mg/L.--.、、..41..2008322286-289.2.———.20093361140-1144.3CarmichaelWWDrapeauCAndersonDM.HarvestingofAphanizomenonflos-aquaeRalfsexBorn.&Flah.var.flos-aquaeCyanobacteriafromKlamathLakeforhumandietaryuse.JournalofAppliedPhycology200012585-595.4TsujimuraSIshikawaKTsukadaH.EffectoftemperatureongrowthofthecyanobacteriumAphanizomenonflos-aquaeinLakeBiwaandLakeYogo.PhycologicalResearch2001494275-280.5RückerJStükenbANixdorfaBetal.Concentrationsofparticulateanddissolvedcylindrospermopsinin21Aphanizome-non-dominatedtemperatelakes.Toxicon200750800-809.6vegesVTapolczaiKKrienitzLetal.PhotosyntheticcharacteristicsandphysiologicalplasticityofanAphanizomenonflos-aquaeCyanobacteriaNostocaceaewinterbloominadeepoligo-mesotrophiclakeLakeStechlinGermany.Hydrobiologia20126981263-272.136J.LakeSci.20142617.、、.198594359-364.8..2001216540-544.9.19802006.20072535-10.10..201035243-46.11LiuYMChenWLiDHetal.FirstreportofaphantoxinsinChina-waterbloomsoftoxigenicAphanizomenonflos-aquaeinLakeDianchi.EcotoxicologyandEnvironmentalSafety20066584-92.12..2005272172-176.13YamamotoYNakaharaH.TheformationanddegradationofcyanobacteriumAphanizomenonflos-aquaebloomstheim-portanceofpHwatertemperatureanddaylength.Limnology200561-6.14SuikkanenSKaartokallioHHllforsSetal.Lifecyclestrategiesofbloom-formingfilamentouscyanobacteriaintheBal-ticSea.DeepSeaResearchPartⅡTopicalStudiesinOceanography2010573/4199-209.15YamamotoYNakaharaH.LifecycleofcyanobacteriumAphanizomenonflos-aquae.Taiwania2009542113-117.16VahteraEConleyDJGustafssonBGetal.Internalecosystemfeedbacksenhancenitrogen-fixingcyanobacteriabloomsandcomplicatemanagementintheBalticSea.AMBIO2007362186-194.17ConleyDJPaerlHWHowarthRWetal.Controllingeutrophicationnitrogenandphosphorus.Science20093231014-1015.18OliverRLGanfGG.Freshwaterblooms-Theecologyofcyanobacteria.NetherlandsKluwerAcademicPublishers2000149-194.19WoodSAPrenticeMJSmithKetal.Lowdissolvedinorganicnitrogenandincreasedheter