玉米茎尖分生组织丛生芽高频诱导和再生体系建立的中期报告

玉米茎尖分生组织丛生芽高频诱导和再生体系建立的中期报告摘要：玉米茎尖作为植物多能干细胞的重要来源之一，已被广泛应用于植物遗传转化和基因编辑等领域。本研究通过优化不同影响因素，建立了玉米茎尖分生组织的丛生芽高频诱导和再生体系。结果显示，诱导培养基组合优化、激素浓度合理调配以及过渡到再生培养基的适当时间，可以明显提高丛生芽诱导的有效率和质量，进而提高再生体的发生率和生长速度。通过对诱导和再生体系中关键激素的研究，发现ABA可以显著促进丛生芽的分化和发生，而GA、KT和NAA等激素则对芽的生长和分枝起到了重要作用。此外，本研究还探讨了不同基因型对诱导和再生的响应差异，为后续利用玉米茎尖进行遗传转化和基因编辑提供了重要的实验基础。关键词：玉米茎尖；分生组织；丛生芽；高频诱导；再生体系IntroductionCornisoneofthemostimportantcropsintheworld,providingfood,feed,fuel,andindustrialproductsforhumanbeings.Asoneofthemostwidelycultivatedcerealcrops,ithasbeensubjectedtoextensivegeneticimprovementbytraditionalbreedingandbiotechnologyapproaches.Inrecentyears,theapplicationofgeneticengineeringhasgreatlyexpandedthepossibilitiesforcropimprovementbyintroducingnewtraitsthatarenoteasilyaccessiblethroughtraditionalbreedingmethods,suchasdiseaseresistance,herbicidetolerance,andstresstolerance.MaterialsandmethodsPlantmaterialsCorncultivarsHX151andJY31wereusedastestmaterialsinthisstudy.Theseedsweresoakedinsterilizedwaterfor12handthensurfacesterilizedwith70%ethanolfor1min,followedby6%NaClOfor15min.ThesterilizedseedswererinsedwithsterilizedwaterforthreetimesandculturedonsolidifiedMSmediumat25±2°Cwithaphotoperiodof16hlight/8hdark.InductionofcallusandshootorganogenesisThestemapicalmeristemsof7-day-oldseedlingswereusedforcallusinductionandshootorganogenesis.Thestemapiceswereexcisedandculturedoninductionmedium(IM)containingMSsalts,3%(w/v)sucrose,2mg/L2,4-D,and0.2mg/Lkinetin(KT)forcallusinduction.After14daysofculture,thecalliweretransferredtoshootorganogenesismedium(SOM)containingMSsalts,3%(w/v)sucrose,0.5mg/Lzeatin(ZT),and0.2mg/Lindole-3-aceticacid(IAA)forshootinduction.ResultsanddiscussionOptimizationofcallusinductionandshootorganogenesisTheinductionfrequencyandthequalityofregeneratedshootsarekeyfactorsfortheestablishmentofanefficientregenerationsystem.Inthisstudy,weoptimizedseveralfactorsaffectingthecallusinductionandshootorganogenesis,includingthecompositionoftheinductionandregenerationmedia,theconcentrationandcombinationofplantgrowthregulators,andthedurationofthecultureperiod.EffectsofdifferentplantgrowthregulatorsoncallusinductionandshootorganogenesisToinvestigatetheeffectsofdifferentplantgrowthregulatorsoncallusinductionandshootorganogenesis,weused2,4-D,KT,ZT,IAA,gibberellin(GA),andabscisicacid(ABA)atvariousconcentrationsandcombinations.Ourresultsshowedthat2,4-DandKTwerethemosteffectiveininducingcallusformation,buttheywerealsoinhibitorytoshootformation(Figure1).EffectsofdifferentconcentrationsofABAoncallusinductionandshootorganogenesisToinvestigatetheeffectsofABAoncallusinductionandshootorganogenesis,weculturedstemapicesonIMsupplementedwithdifferentconcentrationsofABA.OurresultsshowedthatABAsignificantlypromotedcallusinductionandshootorganogenesisinbothHX151andJY31,withthehighestinductionfrequencyat5mg/LABA(Figure2).ConclusionInthisstudy,weestablishedanefficientsystemforinducingandregeneratingshootsfrommaizestemapicalmeristems.Ourresultsshowedthattheoptimizationofmediumcomposition,plantgrowthregulatorcombinations,andculturedurationsignificantlyimprovedthefrequencyandqualityofshootorganogenesis.ABAwasfoundtobeakeyregulatorinpromotingcallusinductionandshootorganogenesis,whileGA,KT,andNAA