生物農(nóng)藥中芽孢桿菌的研究進展

生物農(nóng)藥中芽孢桿菌的研究進展

關于哈夫，chem然控制包括計劃內(nèi)的定居員位控制。有時，這是一個緩慢的，可以使用谷物受體控制。正因為如此，授權的數(shù)量、高、低等級和分配的chem然產(chǎn)品反映了人類和其他人類，而非授權的數(shù)量、水和土壤。就其他的漢納而言，它是一個新的進入領域和控制、錯誤的結果。計劃中的pe低下和未決受害者。這是正因為如此。Innature,thereexitextensiveantagonisticmicroorganismswhicharetightlyconcernedwithplantpathogenicmicrobes,anditisofsignificancetosearchforbiologicalpesticidestocontrolrelatedpathogenicmicrobesfromitsmetabolites.It’sanimportantresearchdirectionofnewpesticidedevelopment.Tocontrolplants’diseaseswithbeneficialmicroorganismcanbedatedbackto1921whenHartelycontrolledPythiumdebaryanumdamping-offwithfungus.Theconcernedmicroorganismsareexpandedthereafter,involvingfungi,actinomycetes,bacteriaandviruses.Bacteriumisfeaturedbylargerpopulation,highpropagation,complexmetabolicactivities,diversifiedeffectsonpathogensandeasilybeingcultivated.Hence,antagonisticbacteriumandmetaboliteplayimportantrolesinbiologicalcontrol.Atpresent,Bacillusspp.,Pseudomonasspp.andAgrobacteriumradiobacterarefrequentlyresearchedandapplied,ofwhichBacillusspp.canbemadeintopowderorwettablepowderandwouldmaintainactivityeventhoughmixedwithchemicalpesticides,thanksforthecharacteristics,suchasheatresistance,droughttolerance,anti-ultravioletandorganicsolvent.ItisclearthatBacillusspp.hasbeenanidealobjectofbio-controlbacterium.ThereportedonesincludeB.subtilis,B.polymyxa,B.cereus,B.megateriumandB.pumilus.Inthisresearch,thebio-controlmechanism,problemsandapplicationprospectoftheBacilluswerereviewedtoprovidereferencesforBacillusspp.applicationinplantpathogenicfungibiocontrol.stwellingfistsmeBiologicalcontrolmechanismofBacillusspp.includesgrowth-promotingeffect,colonization,antagonismandinductionofplantresistance.Itisnotablethatvariedstrains’mechanismsmightdifferevenofthesamespecies,forexample,disease-controllingofsomestrainsmightonlydependononemechanism,butofsomemightbecontributedbymultiplemechanisms.Inaddition,antibacterialmechanismsarenotthesameofdifferentantibioticsubstances,andtheantibioticsubstanceswithsimilarstructures,secretedbysomestrains,stillhavesynergisticeffectsinresistantbacteria.phosphorus/potassitysofterfixationsiph/at生成sytohengexationsivixItwasresearchedin1998thatbiocontrolstrainswouldpromoteplantsgrowthandstrengthendiseaseresistancetofurtherreducediseasedplants.Thepossiblereasonsareasfollows:Thestrainswouldsupplynutrientsforplantsfortheirspecialpropertiesbecauseofphosphorus/potassiumdissolvingactionsandnitrogenfixation;thestrainsproducephysiologicalactivatorstoadjustplantgrowth,suchassecretingauxin,cytokinin,vitaminandphenolicsubstance;thestrainswouldstimulatepropagationoffunctionalbacteriatoreinforcesoilfertility.Heetal.madeatesttoimmersepeppersandcabbagesinB-subtilisBS-2,whichshowedthatIAA,ZR4andGA3contentswerehigher,butA-BAcontentwaslowercomparedwiththecontrol,suggestingthatstrainswouldpromoteplants’growthbyadjustingendogenoushormoneafterenteringplants.bacteriadiph等號,作品分析,計劃設計,使用細則染色,共同進路,ueargation,順利開發(fā),uear種植Competitioneffectincludesspatialandnutrientcompetitions,concerningcolonization,propagation,populationestablishmentofbiocontrolmicroorganisminrhizosphere,onorwithinplantsandinteractionwithpathogenicmicroorganisms.ItisresearchedthatBacillusspp.wouldcolonizeandpropagaterapidlyinplantsandshapeastablepopulationtoreducepathogenicbacteriadisseminationonplantsbycompetitionofspatiallocations.TheresearchmadebyHeetal.indicatedthatBacillussubtilisBS22andBS21wouldcolonizeinnon-naturalreservoirs,suchastomatobyseedsoaking,rootirrigationandleafcoating.However,thereisnobreakthroughinsightonnutrientcompetitionofbiochontrolBacillusspp.andmoreeffortsshouldbepaid.bacillusspp.4和which-those/pertiesindto采用最u.4.3.4.3.4和which-those/pertiege/雙4.4.3.4.3.4.3.4.3.4.3.4.3.4.3.4.3.4.3.4.3.4.3.4.3.4.3.4.3.4.3.4.3.4.3.4.3.4.3.4.3.4.3.4.3.4.3.4.3.4.4.4.4.3.4.3.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.3.4.4.3.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.4.Bacillusspp.hasawiderangeofprotectioneffectsonplantsdiseasedbybacteriaandfungi,andthemechanismhasbeeninterpretedfromdifferentpointofviewsbygeneticexperimentsandbiochemicaltests.ItisresearchedthatantibacterialeffectsofBacillusspp.involveleadingtodeformityofpathogenicbacteria,producingbubble-likematerials,destructiononcellwallsofpathogenicbacteria,overflowofmaterialsincells,hyphadistortion,protoplasmcondensation,expansionofgrowingpoint,andruptureofcellwall.Ingeneral,antagonismofBacillusspp.istocontrolgrowthofpathogenbyassimilationortokillthepathogensdirectly.MostactivesubstancesproducedbyBacillusspp.areofpolypeptide,withfewexceptions,whicharemainlytocontrolgram-positive/negativebacteriaandyeasts.Inaddition,somearecharacterizedbyresistancetobacteria,tumour,andmycoplasma.Theproducedsubstancescanbeconcludedintotheonessynthesizedbynon-ribosomeandtheonessynthesizedbyribosomeaspersyntheticposition.Itisnotablethattheresearchonnon-ribosomalpeptidesofBacillusspp.hasbeenahotissuerecently.Antibioticsubstancessynthesizedbynon-ribosomeofBacillusaredominatedbypeptideswhichconsistofmostcyclicpeptides,somelinearpeptidesandfewaminosugars,suchasAPS.Inaddition,thoseantibioticsubstances,insteadofsynthesizinginribosome,aresynthesizedbyphosphorothioatetemplatemethanism,leadingtoabundantchemicalvariations,forexample,theproductmightbehydroxylation,orhaveL-aminoacid,D-aminoacidandcommonaminoacids.Theseantibioticsubstances,differentwithpreviousantibioticsinmechanisms,wouldovercometheissueofpesticideresistance,andcanbeclassifiedintolinear,cyclicandlinear-cyclicpeptidesasperarrangementofaminoacidsandintosurfactinantibiotics,peptideantibioticsandothersubstancesfromsecondarymetabolism(volatileantibioticsubstances).Itisnotablethatlipopeptidesandpeptideantibioticsaremostimportant,whichareofhighvalueinbiologicalengineering.Lipopeptidesaremetabolitesofgrampositivebacteriaandalipopeptideconsistsofahydrophilicpeptidebondandanoleophilicaliphatichydrocarbonchain.Hence,thespecialchemicalcompositionandmolecularstructurecontributetopromisingfutureinmedicine,food,cosmetics,andmicrobialenhancedoilrecovery.Currently,lipopeptidebiosurfactantsavailablecanbeconcludedintosurfactin,iturinandfengycin.Sincesurfactinwasreportedin1968,newlipopeptidemembersareincreasinglydiscovered,suchasiturinA,B,C,D,E,bacillomycinF,L,baeillopeptin,mycosubtilinandBacillomycinD.Biologicalactivityofisomeridediffersuponsurfactins.Antimicrobialpeptidesarefoundamongallclassesoflifeandarepotent,broadspectrumantibioticswhichhavebeenprovedpotentialasnoveltherapeuticagents.Themechanismsofantimicrobialpeptideactivityhavebeenexplored,namely,antimicrobialpeptideistochangepermeabilitythroughattackingcytomembraneoftargetmicrobesandinnercontentswouldexpose,resultingindeath.What’smore,theantibioticsincellmembraneswouldeffectivelypreventstrainresistance(todrugs)fromproducing.Itisbelievedthatthemechanismoflipopeptideantibioticsistheionchannelbyinteractionwithphospholipids,andchelationofmonovalentanddivalentcationswouldinhibitCyclicAMPphosphodiesteraseandPLAactivity.Itisalsoreportedthatantibioticsubstanceswouldleadtoleakageofprotoplastandruptureofhyphaethroughdissolvingcellmembraneorcellwall.AntifungalproteinssynthesizedbyBacillusspp.ribosomearemainlybacteriocin,chitinase,glucanase,somenon-identifiedproteins.Bacteriocins,ofautoimmunity,arepolypeptideorprotideantibioticsubstancesbygenecoding.Bacilluswouldproducemorebacteriocins,forexample,SubtilinandSubtifosin,producedfromB.subtilis,arehighlyresistanttogrampositivebacteria;chitinase(includingincisionandexcisionenzymes),producedfromBacillusbacteria,isofbiocontroleffect.G3selectedbyGuetal.hasbeendevelopedtobiocontrolagentstocontrolleafspotoftomato.OtherbacisubinsfromBacillusaremainlytodefendpathogenicbacteriafromenteringtomaintainplantliving,andthemechanisminvolvesdegradationofcellwall,injuryofcellmembranechannelsandribosome,inhibitionofDNAsynthesisandcellcycle.Ingeneral,theantibioticsubstancesarediverse,forexample,antibioticsubstances,inthesametypeortotallysame,canbeproducedevenfromdifferentspecies,whichactuallyprovidesmorediversifiedchoicesfordiseasecontrolcausedbyplantpathogeny.Ontheotherhand,aBacillusspp.wouldproducetwoormoreantibioticsubstances,whichwouldenhancepreventioneffectofdiseaseandpostponeplantresistancetokeeppathogenicityofpathogenicbacteriabalanceandstableandtocontroldiseaseeffectivelyforalongterm.bactorlusspp.InducedplantresistanceplaysanimportantroleinbiocontrolofBacillusspp.,whichinvolvesPAL,POD,PPOandSOD,aswellasproteinexpression,tissuelignifications,andphytoalexinproduction.RelatedresearchconcernedendophyticBacillusandrhizosphereBacillus.bacteriogaci制約了新型活性劑和出口品種Bacillusisoneofbiocontrolfactorspreventingplantdiseases.With60yofhistory,someexcellentbiocontrolstrainshavebeeninthestageofindustrializedproductionsincethe1980s,andextensivelypopularizedinfields.B.subtilis,inparticular,hasdrawnthemostattention.However,longtermuseofanantagonisticbacteriummightinfluencemicro-ecologybalance.Therefore,toresearchanddevelopotherBacilluswithbacteriostaticactivitywouldimprovebiodiversityinbiologicalcontrolandbebeneficialforplantgrowth.Withprogress,manyproblemsinbiocontrolBacillusshouldbeconcernedinpractice.國際醫(yī)學回收體meanwhileAnewbiocontrolbacteriumtobeintroducedwouldbehardtobecomeapartoforiginalecosystem.Hence,itiskeyfordiseasepreventioninintroducinganewbiocontrolbacteriuminecoenvironmentasforwhetherthebacteriumwouldcolonizeintheplantsinfectedbypathogenicbacteria,propagatestablyandwhetherthecompetitionwithlocaloneswouldbesuccessful.Meanwhile,biocontroleffectofantagonisticbacteriaisrestrictedbyecologicaladaptability,resistanceandthetime.Hence,itisnecessarytoexploreamoreeffectivesystemorselectintrinsicantagonisticendophyticbacteriainordertopreventinfluencefromexternalenvironmenttominimizeplantdiseases.學生兩組so受保護的stinci生物Beneficialmicroorganismsusuallygrowinspecificenvironmentsinvolvingsoiltype,temperatureandpH.Therefore,itisachallengeforscientificresearcherstosolvetheissueofnarrowadaptationofantagonisticbacteriatoenvironmentandsensitivityofsomestrainstopesticides.Inpractice,effortshavebeenpaidtotransformbeneficialmicroorganismsbygeneticengineeringandmutationbreedingtoachieveidealbio-controlstrainswithhighernutritioncompetiveness,moreproductionofantibioticsubstancesandfastergrowth,whichiskeyforresearchingandapplicationofbiocontrolstrains.u2004范圍Antagonismisoneofimportantindicesofbio-controleffect.Itisdemonstratedthatsomemicroorganismsexistinrhizosphereandleaf,whichwouldpromotegrowthofplants.However,itisstilldifficulttocombineantagonismandgrowth-promotionforbio-controlresearches.Recently,reportshavebeenmadeonantagonisticstrainswhichareofantagonismandgrowth-promotion,simultaneously.Itisprovedthattheseantagonisticbacteriaplayk