增強(qiáng)UV-B輻射對(duì)喜樹(shù)生理指標(biāo)及喜樹(shù)堿含量的影響

王玲麗，周曉君，劉文哲

(1 運(yùn)城學(xué)院 生命科學(xué)系，山西運(yùn)城 044000；2 西北大學(xué) 生命科學(xué)學(xué)院，西安 710069;3 洛陽(yáng)師范學(xué)院 生命科學(xué)學(xué)院，河南洛陽(yáng) 471022)

增強(qiáng)UV-B輻射對(duì)喜樹(shù)生理指標(biāo)及喜樹(shù)堿含量的影響

王玲麗1，2，周曉君2，3，劉文哲2*

(1 運(yùn)城學(xué)院 生命科學(xué)系，山西運(yùn)城 044000；2 西北大學(xué) 生命科學(xué)學(xué)院，西安 710069;3 洛陽(yáng)師范學(xué)院 生命科學(xué)學(xué)院，河南洛陽(yáng) 471022)

摘要:喜樹(shù)(Camptotheca acuminata Decne.)隸屬于藍(lán)果樹(shù)科(Nyssaceae)喜樹(shù)屬(Camptotheca),為抗癌藥物喜樹(shù)堿的主要資源，提高喜樹(shù)堿的積累以滿足臨床需求是喜樹(shù)堿開(kāi)發(fā)的重要途徑。該研究運(yùn)用UV-B輻射對(duì)2年生喜樹(shù)進(jìn)行每天8 h輻射處理，對(duì)1年生喜樹(shù)分別設(shè)置每天2 h、4 h、6 h和8 h的輻射處理，連續(xù)處理12 d后分別測(cè)定各處理喜樹(shù)葉的葉綠素、MDA、游離脯氨酸 (Fpro)含量和SOD活性，以及幼葉、幼枝和根中喜樹(shù)堿含量，分析UV-B輻射對(duì)喜樹(shù)生理指標(biāo)和次生代謝物的影響，以揭示喜樹(shù)堿為喜樹(shù)適應(yīng)UV-B輻射逆境的防御產(chǎn)物。結(jié)果顯示：(1)2年生喜樹(shù)經(jīng)UV-B每天8 h輻射處理12 d后，葉綠素含量較對(duì)照顯著降低，而MDA、Fpro和喜樹(shù)堿含量均增加，說(shuō)明每天8 h UV-B輻射對(duì)2年生喜樹(shù)產(chǎn)生了較強(qiáng)的脅迫傷害。(2)1年生喜樹(shù)經(jīng)UV-B輻射處理12 d后，隨著每天UV-B輻射時(shí)間的增加，葉綠素含量不斷降低，F(xiàn)pro含量顯著增加；每天2～6 h處理的MDA含量與對(duì)照無(wú)顯著差異，但總體隨處理時(shí)間增加呈上升趨勢(shì)；每天8 h UV-B輻射的MDA含量較對(duì)照顯著增加；SOD活性隨每天處理時(shí)間的延長(zhǎng)呈先下降、后上升、再下降的變化趨勢(shì)，說(shuō)明每天8 h的UV-B輻射對(duì)一年生喜樹(shù)也產(chǎn)生了脅迫傷害。(3)1年生喜樹(shù)幼葉、幼枝和根中喜樹(shù)堿含量隨著每天UV-B輻射時(shí)間的延長(zhǎng)均呈遞增趨勢(shì)，而且每天8 h輻射處理的喜樹(shù)堿含量均最高，其中幼葉和幼枝中喜樹(shù)堿含量顯著高于根中含量。實(shí)驗(yàn)結(jié)果表明，增強(qiáng)UV-B輻射對(duì)喜樹(shù)造成了一定的傷害，而喜樹(shù)通過(guò)改變生理以及次生代謝機(jī)制，以進(jìn)一步產(chǎn)生喜樹(shù)堿來(lái)響應(yīng)增強(qiáng)UV-B的脅迫。

關(guān)鍵詞:喜樹(shù)；UV-B輻射；喜樹(shù)堿含量；生理指標(biāo)

Camptotheca acuminataDecne.belongstotheNyssaceaefamilyandisaperennialdeciduousplantthatisuniquetoChina,andismainlydistributedalongtheYangtzeRiverandSouthwestprovincesofChina[1].Theplantisknowntobotanyandmedicinebecauseitsvariousorganscontainthealkaloidcamptothecin(CPT)anditsderivativeswhichhaveimportantbiologicalactivities.

CPT,apentacyclicquinolinealkaloid,isaneffectivemedicineincancertreatment,whichwasfirstisolatedfromthestemofC. acuminata,andthestructuresofthisalkaloidweredeterminedbyWallandhiscollaborators[2].CPTisknownforitsremarkableanti-canceractivitytoinhibittheeukaryoticDNAtopoisomeraseI[3].Italsoinhibitsretrovirusessuchasthehumanimmunodeficiencyvirus(HIV)andtheequineinfectiousanemiavirus[4].CPTisavaluablecompoundasachemicalprecursoroftopotecanandirinotecanwhichwereapprovedbytheUSFoodandDrugAdministrationin1996forthetreatmentofovarianandcolorectalcancers[5].

AlthoughmuchisknownaboutmanyfactorswhichaffecttheaccumulationofCPTinC. acuminata,stillonlylittleisknownabouttheeffectofUV-BradiationonCPTaccumulation.BecauseofthepromisingclinicalusesofCPT,itisimportanttoinvestigatethefactorsaffectingCPTyieldinplantmaterial.Inthepaststudy,droughtcanincreasedCPTcontentinleavesofC. acuminata[6].MethyljasmonicacidandthetreatmentsofyeastextractonleafdiscspunchedfromC. acuminataseedlingspromotedthemRNAexpressionoftryptophandecarboxylase(TDC),akeyenzymeinvolvedinCPTbiosynthesis[7].Similarly,methyljasmonicacidandyeastextracttreatmentsonC. acuminatacellsuspensionculturesincreasedCPTaccumulation[8].ItcanenhanceCPTproductionbyethanoladditioninthesuspensioncultureoftheendophyte, Fusarium solani[9].Wanget al[10]reportedCPTcontentdecreasedafter10daysUV-Bradiation,andincreasedafter40daysUV-Bradiation.ButtheydidnotstudythechangeofCPTcontentbetween10daysUV-Bradiation.ThisstudyinvestigatedtheeffectsofUV-Bradiationbetween12daysontheaccumulationofCPTinC. acuminata,whichwouldprovideabasisformaximizingCPTyieldanddesigninganaffectiveCPTproductionsystem.

1Materials and methods

1.1Plant materials

One-year-oldandtwo-year-oldC. acuminataplantsweregrownfromseeds.SeedsofC. acuminatawereselectedtogatherfromBotanicalGardenofXi’aninNovemberof2012and2013,thenrespectivelyembeddedinwetsandat25 ℃inMarchthenextyear.Aftertheseedsgeminated,theuniformseedlingswereselectedandtransplantedintoflowerpotsinthebotanicalgardenofNorthwestUniversity(Xi’an,China).

1.2UV-B radiation

SupplementalUV-BradiationwasprovidedbyfilteredGucunbrand(GucunInstrumentFactory,Shanghai,China) 30Wsunlamps.Lampsweresuspendedaboveandperpendiculartotheplantedrowsandfilteredwitheither0.13mmthickcellulosediacetate(transmissiondownto290nm)forUV-Birradianceor0.13mmpolyesterplasticfilms(absorbsallradiationbelow320nm)asacontrol.Thedesiredirradiationwasobtainedbychangingthedistancebetweenthelampsandtheplants.ThespectralirradiancefromthelampswasdeterminedwithanOptronicsModel742 (OptronicsLaboratories,Orlando,FL,USA)spectroradiometer.Thespectralirradiancewasweightedwithageneralizedplantresponsespectrumandnormalizedat300nmtoobtainthedesiredlevelofbiologicallyeffectiveUV-Bradiation.Thelampheightabovetheplantswasadjustedtomaintainadistanceof0.15mbetweenthelampsandthetopoftheplantsandprovidedsupplementalirradiancesof2.1effectiveuw·cm-2.Two-year-oldplantswereirradiatedfor12daysand8hdaily.InordertofurtherillustratetheeffectsofsupplementalUV-Birradiance,one-year-oldplantswereirradiatedfor12daysandrespectivelyarranged2h, 4h, 6hand8hradiationdaily.FilteredUV-Bradiationwasregardedasthecontrol(CK).

1.3Determination of physiological parameters

PhysiologicalparametersweredeterminatedinleavesofC. acuminata.Chlorophyllwasextractedwith96%alcohol,andchlorophyllcontentwasmeasuredaccordingtothemethodofZhang[11].Malonaldehyde(MDA)contentwasdeterminedaccordingtothemethodofHeathandPacker[12].Fprocontentwasextractedfromleavesin3%aqueoussulphosalicylicacidandestimatedusingninhydrinreagent[13].Superoxidedismutase(SOD)activitywasdeterminedaccordingtothemethodofGiannopolitisandRies[14].

1.4CPT content analysis

1.4.1HPLCanalysisTheHPLCsystemconsistedofaHPLCpump(LC-10ATvp),areversedphasecolumn(VP-ODS, 150mm×4.6mm, 5μm)andaUV-VISdetector(SPD-10Avp)forthedetectionofCPTat254nm[15].Sampleinjectionvolumewas10μLaccordingtothepresumablealkaloidcontent.Theflowratewas1.0mL·min-1.Themobilephaseusedwasmethanol/water(62/38,V/V).Columntemperaturewas25 ℃.Underthiscondition,theHPLCchromatogramsofthestandardandsamplesolutionswereshowedinFig.1.CPTstandardwaskindlysuppliedbyDr.H.BischoffofBoehringerIngelheimPharmaKG.inGermany.

Fig.1　The HPLC chromatograms of the standard and sample (peak 1: camptothecin)

1.4.2StandardcurveCPTstandard2.5mgwasputin50mLvolumetricflask,suitableamountofchromatographicmethanolwasadded,andmeteredvolumeaftertheultrasonichelpingdissolve.Thesolutionwasshakedandfilteredwith0.45μmmicroporousmembrane,then0.05mg·mL-1standardsolutionwasgot. 2, 3, 5, 8and10mLofCPTstandardsolutionwerepreciselymeasuredandputin10mLvolumetricflask,dilutedwithchromatographicmethanol,thenrespectivelymeteredvolume.ThestandardcurveforCPTwasconstructedbyseparateinjectionof10μLoftheabove-mentionedstandardsolutionaccordingtotheabovechromatographyconditions.TheregressionequationbetweenpeakareaYandtheconcentrationofcamptothecinX (μg·mL-1)was: Y=16 686X-6 577.5, R2=0.999 3.

1.4.3DeterminationofCPTcontentThesamplesweredriedintheshadeandgroundedinamortar. 100mgofthesampleswastransferredtoacentrifugetubeand4mLmethanolwasadded.Afterextractedwithsonicationfor10minatroomtemperature, 30mLwaterand40mLdichloromethanewereaddedandthiswasmixedvigorouslyfor5minonamagneticalstirrer[16],centrifugationfor10minat2 000r·min-1yieldedtwophases.ThedichloromethanephasewhichwasprovedtocontainCPT,wasrecoveredandevaporatedtodrynessinvacuumusingarotavapor.Theremainingresiduewasre-dissolvedinHPLC-grademethanol(1mL),filteredwith0.45μmmicroporousmembranethengotsamplesolutionwhichwasusedforthedeterminationofCPTcontent.Samplepeakswiththesameretentiontimetostandardswereverifiedbyspectralscananalysis．

2Results

2.1Effects of UV-B radiation on two-year-old C. acuminata

Thecontentsofchlorophyll,MDAandFproaswellasSODactivityweremeasuredaftertwo-year-oldplantswereirradiatedwithUV-Bradiation.TheresultsshowedinTable1,chlorophyllaandbcontentswerereduced,chlorophylla/bratiohadalesserextentincreaseunderenhancedUV-B.MDAandFprocontentsincreased.TheactivityofSODwasreduced.CPTcontentsinyoungleaves,youngshootsandrootofC. acuminatahadobviouslyincreasedafterUV-Btreatmentcomparedwiththecontrol,CPTcontentinroothasnosignificantdifferencecomparedwiththecontrol.

2.2UV-B radiation effects on chlorophyll contents in one-year-old C. acuminata

TheeffectsofenhancedUV-Bonchlorophyllcontentsinone-year-oldC. acuminatawereshowninFig.2.Thesametotwo-year-oldplant,chlorophyllcontentsdecreasedafterUV-Bradiation,andwiththetreatmenttimeprolonging,thechlorophyllaandchlorophyllbcontentsgraduallydecreased.Thetotalchlorophyllcontentof2h, 4h, 6hand8hUV-Btreatmentdailywasrespectivelyreducedby9.4%, 10.8%, 15.7%, 26.8%thanthecontrol.While8hUV-Btreatmentdaily,chlorophyllaandbcontentsdecreased26.4%and27.8%,respectively.Chlorophylla/bratiohadalittlechangecomparedwiththecontrol,itissuggestedthatthedifferenceofdestroyedextentaboutchlorophyllaandbisnotobvious.

Table 1　Effects of UV-B radiation on physiological indices

Note:Eachassaywasrepeatedthreetimesfromthreeindependentexperiments.Thedataarethemeans±SEMofthreereplicates.Asterisk(*)indicatesstatisticallysignificantdifference(P< 0.05;ANOVA,Tukeytest).

2.3UV-B radiation effects on MDA, Fpro contents and SOD activity in one-year-old C. acuminata

Each assay was repeated three times from three independent experiments. The data are the means ± SEM of three replicates. Different letters indicate statisticallysignificant differences (P< 0.05; ANOVA, Tukey test).The same as belowFig.2　Effect of UV-B radiation on chlorophyll content in one- year-old C. acuminata

Fig.3　Effects of UV-B radiation on MDA, Fpro contents and SOD activity in one- year-old C. acuminata

Fig.4　Effect of UV-B radiation on CPT content in one-year-old C. acuminata

2.4UV-B radiation effects on CPT contents in one-year-old C. acuminata

UV-BradiationalsohadobviouseffectsonCPTcontentsinyoungleaves,youngshootsandrootsofone-year-oldC. acuminata (Fig.4).WhenthetimeofenhancedUV-Btreatmentreachedto8hdaily,theCPTcontentsweresignificantlyincreasedcomparedwiththecontrol.WiththetimeofUV-Bradiationprolonging,CPTcontentsinyoungleavesandshootsincreasedfasterthanthatintheroot,andCPTcontentofyoungleavesincreasedto0.230%from0.106%ofthecontrolgroupafter8hradiationdaily,youngstemincreasedfrom0.064%to0.158%,andtheincreaseofCPTcontentinroothadalittlechange,increasedfrom0.036%to0.065%.

3Discussion

UV-Bradiationhasmanyeffectsonplants.AlthoughtherearesomesignificanteffectsaboutUV-Bradiationonplantgrowthanddevelopmentincertainspeciesandecosystems,itturnedoutthattheoveralldamagingeffectsofabove-ambientUV-Baremodestordifficulttodetectundernaturalconditions[17].Anexaminationofmorethan200plantspeciesrevealsthatroughly20%aresensitive, 50%aremildlysensitiveortolerantand30%arecompletelyinsensitivetoUV-Bradiation[18].UV-Bradiationactsasakindofenvironmentalstress,andtheplantwouldhavetoadapttoUV-Bradiationtominimumthedamagewhenthestresslevelreachtoalimitation.WithashortperiodofUV-BradiationinArabidopsis thalianaseedlings,rootswereelongatedandchlorophyllandsolubleproteincontentwereincreasedinleaf,butprolongedUV-Bradiationinhibitedtheelongatedrootlength,causedleafchlorophyllcontent,solubleproteincontentdecrease[19].TheeffectsofenhancedUV-Bradiationonplantphysiology,morphology,growthandbiomasshavebeeninvestigatedextensively.EnhancedUV-Bradiationmayexertanadverseinfluenceonthephysiologicalandbiochemicalprocessesofplants.Inthisstudy,wereportedtheresponsesofC. acuminataplanttoenhancedUV-Bradiation.ThisissupportedbytheearlierfindingsofintraspecificresponsesinflavonoidmetabolisminCucumis sativus[20],soybean[21]andA. thaliana[22]andinflavonoidcontentandchlorophyllcontentdecreasedinrice[23].

UV-BradiationhadobviouseffectsonchlorophyllcontentsofC. acuminata.TheUV-Bradiationmechanismofdecreasingchlorophyllcontentswasstillnotclear.ChangesinchlorophyllcontentshaveoftenbeenusedasanindextoassessthedegreesofUV-Bradiationsensitivity.Inthisstudy,chlorophyllcontentsinC. acuminataleaveswerealsosensitivetoenhancedUV-Bradiation.UV-Bradiationsignificantlydecreasedchlorophyllcontents,primarilybecauseUV-Bradiationdestroyedthestructureofthechloroplast,inhibitedthesynthesisofnewchlorophyllanddestroyedthestructureofchloroplastenvelopemembraneandincreasedthedegradationofchlorophyll.Yanget al.[24]reportedthatUV-Bradiationreducedthephotosyntheticpigmentinleaves(includingthecontentsofchlorophyllandcarotenoid,especiallythecontentofchlorophylla).ZhangindicatedthatUV-Bradiationofdifferentintensitycanmakethegrowth,chlorophyllcontentsdecreaseinVicia fabaseeding[25].TheseresultsshowedthatenhancedUV-Bradiationmadetheplantchlorophylldamage,changedtheproportionofchlorophyllaandchlorophyllb,affectedtheformationofphotosyntheticproteincomplexes,andinhibitedtheformationoforganelles.

Freeprolineaccumulationhasbeenobservedinresponsetoawiderangeofabioticandbioticstressesinplants.Prolineisconsideredtobeoneofthefirstmetabolicresponsestostress,andisperhapsasecondmessenger[29].Environmentalfactorsincludingwaterdeprivation,salinization,highandlowtemperature,heavymetaltoxicity,pathogeninfection,nutrientdeficiency,atmosphericpollutionandUV-radiationinducetheelevationoftheprolinelevelinplants.InC. acuminataplant,enhancedUV-BradiationmadeFprocontentincrease,itmaybeanadaptiveresponsetoresistUV-Bradiationstress.AnegativecorrelationbetweenSODactivityandFprocontentwasfoundunderUV-BstressconditioninC. acuminata.

MDAistheproductofmembranelipidperoxidationwhentheplanttissuesufferedoxidativestress,whichreflectsthedegreeofcellmembranelipidperoxidationandtheplanttorespondtostress.Inthispaper,MDAcontentshavenosignificantdifferencebetween6hUV-Bradiationcomparedwiththecontrol,however,MDAcontentwassignificantlyincreasedafter8hUV-Btreatment.AlowdoseofUV-BstressinducedtheproductionofacertainamountofROS,whileinherentSODinC. acuminatarapidlyeliminatedtheseROS,andresultedinthedecreaseofSODactivity.WhenthetimeofUV-Btreatmentreachedto8hdaily,alargenumberofROSweregeneratedandcausedmembranelipidperoxidation,soMDAcontentwassignificantlyincreased.Inconclusion,thereisacertaincorrelationamongthechangeofSODactivity,FprocontentandMDAcontentunderUV-Bstress,thedecreaseofSODactivityisaccompaniedbytheincreaseofMDAor/andFprocontent.

Undertheconditionofadversity,inadditiontotheplantphysiologicalindicescanbeinducedsomechanges,thesecondarymetabolismofplantwillalsobechanged.Plantsinteractwiththeirenvironmentbyproducingadiversearrayofsecondarymetabolites,oneofwhichisalkaloid.Bioticandabioticenvironmenthaveimportantrolesinthesecondarymetabolizingofplant.Asasecondarymetabolite,CPTmayplayacrucialroleduringbioticandabioticstresses,whichposeagreatimpactonalkaloidbiosynthesisandaccumulation[30].TheincreaseofalkaloidaccumulationduringseedlingsdevelopmentwasobservedandthisshowedthatCPTmayplayadefensivefunctionfortheplantsduringthisvulnerablestageoftheirlifecycle.UVlightresponsiveregionsinthepromoterofthetryptophandecarboxylase(tdc)geneinCathatranthus roseushadbeenidentified[31].Inourstudy,UV-BradiationcanobviouslyenhanceCPTcontentinC. acuminata,wehypothesizethatUV-BmightstimulatetheexpressionoftdcgeneandincreaseCPTaccumulationinC. acuminata.CPTaccumulationinducedbyUV-BradiationdemonstratedthatCPTwasinvolvedinplantdefenseagainstUV-Bradiation.WhenC. acuminatasufferedUV-Bradiationinalowdose(2h, 4h),CPTcontentwasincreasedslowly;withthetimeofUV-Bradiationincreasing(6h, 8h),CPTcontentwasincreasedrapidly,whichillustratedthatthelongtimeofUV-BradiationcausedcertaindamagetoC. acuminata,andC. acuminatadefensedprimarilybyincreasingthesecondarymetabolites-CPT.Moreover,CPTcontentsinyoungleavesandshootswereincreasedmoreobviouslythanthoseinroot,itindicatedthatenhancedUV-BradiationcouldpriorityimproveCPTaccumulationofaerialorganinC. acuminata,becauseaerialorganmainlysufferedUV-Bstress.

EnhancedUV-BradiationcausedcertaindamagetoC. acuminata,notonlyaffectsthemorphologyofC. acuminata[10],butalsoaffectsthephysiologicalandbiochemicalmetabolism.UnderthestressofUV-B, C. acuminataitselfdefensedthisstressbychangingphysiologicalindices(i.e.,SODactivity,MDAandFprocontent)andsecondarymetabolismtoaccumulateCPT.Therefore,thechangesofphysiologicalindicesandCPTaccumulationarealsotheadaptivemechanismtoresponsetothestressofenhancedUV-BradiationinC. acuminata.Furthermore,intheindustryplantingofC. acuminata，themethodofsupplementing8hUV-BradiationdailytopromotetheincreaseofCPTcontentisfeasible.

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(編輯:潘新社)

EffectsofEnhancedUltraviolet-BRadiationonPhysiologicalIndicesandCamptothecinContentinCamptotheca acuminataDecne

WANGLingli1，2,ZHOUXiaojun2，3,LIUWenzhe2*

(1DepartmentofLifeScience,YunchengUniversity,Yuncheng,Shanxi044000,China; 2CollegeofLifeScience,NorthwestUniversity,Xi’an, 710069,China;3SchoolofLifeSciences,LuoyangNormalUniversity,Luoyang,He’nan471022,China)

Abstract:Camptotheca acuminata Decne. (Nyssaceae) is a major source of anticancer camptothecin (CPT). It is imperative to induce CPT accumulation in order to develop CPT production strategies to satisfy clinical uses of CPT. In this study, two-year-old C. acuminata were dealt 8 h each day with UV-B radiation for 12 days, and one-year-old C. acuminata were respectively arranged to radiate 2 h，4 h，6 h and 8 h with UV-B radiation each day for 12 days. The contents of chlorophyll, MDA and free proline (Fpro), the activity of SOD in leaf and CPT content in young leaves, young shoots and root were separately measured after UV-B treatment. In order to reveal that camptothecin is the defense product of UV-B stress, the effects of UV-B radiation on the physiological indices and secondary metabolites were analyzed. The results showed that: (1) in two-year-old C. acuminata, chlorophyll content was significantly decreased, MDA, Fpro and CPT contents were significantly increased after 8 h UV-B treatment daily. It indicated that 8 h UV-B radiation caused great stress influences on two-year-old C. acuminata. (2) In one-year-old C. acuminata, with the time of UV-B radiation increasing, chlorophyll content was gradually decreased; Fpro content was significantly increased; MDA content had no significantly difference between 2 h and 6 h UV-B radiation, but significantly increased after 8 h radiation compared with the control; SOD activity decreased firstly, then increased, lastly decreased with the time of UV-B radiation prolonging every day. It showed that 8 h UV-B radiation also caused stress influences on one-year-old C. acuminata. (3) CPT contents in vegetative organs of one-year-old C. acuminata were gradually increased with the time of UV-B radiation prolonging, and the contents were the highest after 8 h UV-B radiation each day. Moreover, CPT content increased more obviously in young leaves and young shoots than those in roots. It confirmed that enhanced UV-B radiation caused certain damage to C. acuminata, and C. acuminata responded to this stress by not only changing physiological indices, but also changing secondary metabolism to accumulate CPT.

Key words:Camptotheca acuminata; ultraviolet-B (UV-B) radiation; camptothecin (CPT) content; physiological index

文章編號(hào):1000-4025(2016)05-0979-08

doi:10.7606/j.issn.1000-4025.2016.05.0979

收稿日期:2015-10-12;修改稿收到日期:2016-03-28

基金項(xiàng)目:國(guó)家自然科學(xué)基金(31270428)

作者簡(jiǎn)介:王玲麗(1980-)，女，在讀博士研究生，講師，主要從事結(jié)構(gòu)植物學(xué)研究。 E-mail：wanglingli_521@163.com *通信作者:劉文哲，教授，博士生導(dǎo)師，主要從事結(jié)構(gòu)植物學(xué)與繁殖生態(tài)學(xué)研究。E-mail: lwenzhe@nwu. edu.cn

中圖分類(lèi)號(hào):Q945.79;

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