A study of the relationship between wild rice(Oryza rufipogon) and japonica rice varieties(Oryza Sativa L.): Using phytoliths to investigate tubercle forms developed from the upper epidermal cells of Oryza rufipogon and japonica rice varieties hulls

THEBULLETINOFOKAYAMAUNIVERSITYOFSCIENCENo､５１App53-56(2015）

Astudyortherelationshipbetweenwildrice(0F:Ｗ〃J《/2p､即"）

肌d’UMP伽加ricevarieties(ｏｒﾘﾉｚａＭｶﾞＷＪＬ.）

－UsingphytolithstoinvestigatctuberclefbrmsdcvelopedfromtheUpper

epidermalcellso缶Ｏ卵a7z(/iipOgMandﾉ叩○"jcaricevarictiesllulls-ＨｉｒｏａｋｉＫＯＢＡＹＡＳＨＩ Ｄｅｐα'T"ＤＣ"/q/SbcjMZ/blmα/ｊｏ",FtJc"/iyq/Y)ybmzaZ姻 ○ノヒI〕’α"ｚａＵ)､ﾉelm〕ﾉQ/・Sbie"Ｃｅ ／－１Rjdbj-cAo,Kim-Az‘,OAzIWmzα700-000ｺ｡ﾉtJpα〃 (ReceivedSeptember29,2015;acceptedNovember9,2015）

FocushasbeenrecentlyplacedontherelationshipofbetweenwildriceａｎｄＯｒｿZdusaZiwuL．,withsomestudies,using

DNAanalyses,suggestingthat血PC"JcduwasoriginatedfromO帆０，１/mpmgo"・ThiSstudyaimedtoexanmnevariations intuberclefUrmsdevelopedfmmtheupperepidermalcellsofOD:ﾘﾉZａ'u《/zpQg⑪〃couectedfromdifferentareasofthe

world，usingphytolithsextractedfromtheirhulls･Ｔｈｅｒｅｈａｖｅｂｅｅｎｖｅｌｙｆｅｗｒｅｐｏｒｔｓｏｎｔhistopic･Moreove喝a

comparisonwithtuberclefDrmsof”PC"JcUuvarietieswasattemptedtoinvestigatetherelationshipbetweencultivated

● ﾉｕＷ"JcuuandOJyZaJⅥ《/mpQgwo・TheresultsuggeststhatthetuberclefUrmofOJyZuzlu《/ZIMgwUismuchthesameasthatof

tropicalﾉＵＷ"たα;howevemtisquitedifferenttothatoftemperateﾉUUpo"妃α・ThisindicatesthatOP:ﾘﾝZdmvZpq即〃and

temperateﾉｂＷ"Jcuucultivatedinpaddyfieldshavenodirectrelation・Ontheotherhand,theO帆α'J《/;pQgo〃typeｏｆ

● tuberclefDrmcurrentlyoccursinuplandriceinJapan． Keywords:phytolith;。'Ｗα'Y(/ipogo";/ZJpo"にα;hulL LIntroduction

AsisthecasefbrOﾉﾂｍＭｊｗＪＬ,ithasbeenconsideredthatﾉ”o"jcaandj"此ahaveacommonorigin(Oka，

1988)ｏｒﾉﾋ柳"zcawasoliginatedmmj"血cα(Tin9,1957).However,accordmgtorecentDNAanalyses(Sato，

1996,2008,2013),itissuggestedthattheancestorisnotconunon,witMIpo"icaoriginatmg仕ｏｍＯｒ〕/２，W/ipogD"，

andtheemelgenceofm此aistheresultofhybridizationbetween/ZZpo"jcaandanunknownwildOﾉﾌﾉ、､Tb

exammewhetherdifferencesbetweentuberclefbnnsofOﾉﾌzzzz〃〃ogo〃collectedffomdiffbrentareasofthe

worldexistornot,phytolithsorigmatingffomtheirllullswereexamined・Aphytolithismostlyconsistedofsilica

andistherefbrecalleda“silicabody.”TY1isstudyexammessiliceousphytolithsofmberclefbmlsdeveloped凸om

theupperepidermalcellsofO叩arz4/ipogo"hullsandexammesitsrelationshipwiththatof/apo"icavarieties．

２.MaterialsandMethods

FourkindsofOryza'１(/iipogD〃sanmD1eaccessionsanalyzedinthisstudyoriginatedBomtheNational

BioresourcePrqject,ＭＥXT,Japan・Thesesampleswereidentifiedasfbllows(Figlandnblel):Ｗ0593,Ｗ1236,

Ｗ1294,andW1954(thecodelistedherearethesamplecodesusedmthesourceinstimtion).Thesefbursamples

werecollected丘omfbura１℃asmAsiaandOceania,namelyChina,thePhilippmes,Malaysia,andPapuaNew

GuineaEachsamplewasseparatelyashedfbrextractmgsiliceousphytolithsoftuberclefbnnshmtheirhulls．

5４ HiroakiKoBAYAsHI １２３４ Fig.１FoursamplesofOrl！ZuuM/ZpQgmDusedfbrextractingphytoliths:1-VⅧ503;2-Ｗ1236;3-Ｗ1294;4-Ｗ1954． （Scale:ｍ、） 3.PhytoUthextraction (1)Eachsamplewascleanedmdeiomzedwaterfbr 30nnusinganultrasoniccleaningmachine.(2)Each samplewasdriedmanelectricfiJrnanceat85oCfbr 4h(3)Usmgasetoftweezersandasmgicalknifb,all segmentsofthehullwereremovedmmeachsample， andthesesegmentswerebumtmanelectricfUmaceat 315oCfbr9-19huntilUlecolorchangedtowhiteorgrayB nblelPlacesoforiginofO'yZuJM/ipa印〃 ＳａｍplesusedfDrextractingphytoHths． ＮＣ Ori2inalplace WO593BinjaiRcndah,Malaya(Malaysia Ｗ1236Madang,AustlalianNewGuinea（Papua NcwGuinea Ｗ1２９４Mususan,Mindanao,thePhilippines Wl954 China ThetimereqUireddependedonthetllicknessorhardnessofthehulL(4)Thehullsweretreatedwith30mlof30％ H202so1utiontoremovetlleircarbonsThehullsegmentswerethenheateduntiltheybecamealmostwhitein colorb(5)Afterrelnovmgcarbons,deionizedwater(50ｍl)wasaddedtothisresidue,and20IL1aliqUotsofliqUid containingphytolithcomponentswereplacedonslidesuslngamicropipetteorstandardpipette,anddriedma desiccatorfbr3-4h(6)Coverglasseswereplacedoverdriedsampleswithamountingreagentandwereobserved underanopticalmicroscopeat200×ａｎｄ４００ｘｍａｇｍｆｉｃations・MicrophotographswereobtamedwithaSIR digitalcameramountedonthemicroscope． ４.Resmtsanddiscussion nbe１℃lesandtheirmorphologicalcharactershavebeenclassifiedbyTakahashietaL(2005)andreviewedby Kobayashi(2013).Theclassificationofmberclesinthissmdyisbasedonthesereports､Atotalofl2-24slides weremadepersample,with70slidesandl40危amesexaminedoverall・A11tuberclefbmlsofOr)ﾉzzJ7z4/iipogo〃 samples丘omdifferentareaswereoftypicaltypeC(Fig.２).Considerablylargerpapillaedevelopedwithfbnns similartostrumaePapillaeonadjacentlateralbranchesoflongcellsdidnotfbrmintricatepatterns,butfacedeach otherandfbrmedcircularconesTheseremarkablecircularconeswereconcentratedatonespotandweresimilar mappearancetocloselypackedmountainswithsharppeeksDetaileddiHerenceswerenotobservedmtypeCof tllefbursamples・TypeCistypicalmtropicaMIpo"jca(THkahashietaL,ｏｐ､Cit.).InJapan,thistypecanbe observedmuplandriＣｅ;thesericevarietieshavedescendedhPomtropicalﾉﾋIPO"jca(Tnkahashi2008,2011)The ratioofuplandriceiscurrentlyextremelysmallmJapan・Incontrast，mostricevarietiescomprisetheIice cultivatedmpaddyfields,withthedominantspeciesbeingtemperate/ＺＷｍｃａ・ThetUberclefbrmoftemperate ﾉ〃o"jcaistypeS(TakahashietaLop､Cit.;Kobayashi2008).Amarkedstrumacanbeobservedatthelateral branchoftllelongcellandthepapillaexitsBPomthisstruma､Strumaeonadjacentlongcellsfblmanintricate pattern・Thistypedoesnotoccurintropical/ZZpo"zcaandmdIcavarieties・Therefbre,theresultofinvestigating

Astudyoftherelationshipbetweenwildrice(O”zαγz(/iiPOgo")andjtJPo"jczzricevarieties(OがｚａＭ伽Ｌ､）５５ tuberclefbrmssuggeststhattropical/qpo"icqhasadirectrelationtoOr〕/za7z4/zpogo",anditissuggestedthatthe latteristheancestorofthefbrmerandthatthelatterhasnorelationtotemperate/ZZpo"ｊｃａ・Recentstudies (Takahashi2008,2010)haveshownthattypeCandSalreadyexistedintheearlyJomonperioddated7,600-5,500 yearsagoinJapanTheappearanceofbothtypesseemstobeancient・ＡｓｆｂｒｔｙｐｅＳ,othervarietiesofOﾉﾌﾉzZJ “/ipogo"mayhavethistype・Otherwise,typeSispossiblytheresultofhyblidizationofOﾉｯz、綴z4/ipogo〃with typeCandotherunknownOｸﾞﾂzzzspecies．

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Z 4 Fig・ZMicrophotographshowsphytolithsoftuberclesofupperepidermalcellsofO'TZaruﾘｶﾞpQgo〃hulls:1-Ｗ593； ２－Ｗ1236;３－Ｗ1294;４－Ｗ1954． （MagnifncationapproxmateIy400x） 5.ConcluSion ThetuberclefbnnofOr〕』zα'１(/fpogo〃wasoftypeCTherefbre,itissuggestedthatO'Ｗα'Ｔｌ/iipogo〃isthe ancestoroftropicaljaponicaandthistypeoccursin叩landricemJapan・Furtherinvestigationisrequiredtoclarify therelevanceofOﾉｯzzJrU/ipogo"andtemperate/”o"icacultivatedmpaddyfields． Acknowledgements lthanktheNationalBioresourcePrqject,ＭＥXT,Japan,fiPomwhichsamplesofOﾉﾌﾉzzzrz(/1ipogo"weresou1℃ed fbrthissmdyB References Kobayashi,Ｈ・’２００８ThestudyofOIyzzlsativzL､fbundatsitesinJapan:Plantopalanalysisoftuberclesatepidermalcells oftheglumesofOI:yzzIsZI〃vzHL・MemorialcollectedpapersfbrProfChousukeSerizawa“Archaeology)Ethnologyand History>''RokuichiSyobouCo.,Ｌｔｄ,Tbkyo:５95-606(ｉｎJapanese） Kobayashi,Ｈ・’2013.SpeciesofOI:yzzYsativHLstoredinAoyamacastledestroyedinthelatel6thcentｕｒｙＡＤ,Okayama， westernJapan-P1antopalanalysisoftuberclesdevelopedhFomtheepidermalcellsoftheglumesofOIyzasativziL.－ ThebulletinofOkayamaUniversityofScie､Ce,ｎｏ､49,Ａ:１－４

5６ _{HiroakiKoBAYAsHI} Oka,Ｈ・’1988.OriginofCultivatedRice・JapanScientificSocietiesPress,Ibkyo:２５４

Oka,Ｈ､,(ed・andtranslater)1997.TheoriginofricecultivationatsitesmChmaYasakaShobouCo.,Ltd.,Ibkyo.(ｍ

Japanese） Sato,Ｙ,1996.RicecroppingcivilizationthroughDNAanalysis・ＮＨＫPress,Tbkyo.(ｉｎJapanese） Sato,Ｙ,2008.HismryofRice・町otoUnvPres8,Iqroto.(ｉｎJapanese） Sato,Ｙ,２０13.Letisknowandeatricecultivatedinalloftheworld・IwanamiJuniorPaperbacks・IwanamisyotenCo.,Ltd.， Ibkyo(ｉｎJapanese） Tnkahashi,Ｍ､,ThUjima,Ｍ､,Kobayashi,Ｈ・’2005.TheexcavationofHikozakisheU-mound,Okayamaprefecture・KDukogaku JOurnalno,527:28-31(ｉｎJapanese） IbIkahashi,Ｍ，2008.EpidemictissuesathuUsofAsianriｃｅａｎｄｉｔ,sclassification・MemorialcoUectedpapersfbrProf ChousukeSerizawa"ArchaeologyEthnologyandHistory>''RokuichiSyobouCo.,Ltd.,Ibkyo:57-66(ｉｎJapanese） 脳kahashi,Ｍ,,2010.P1antcultureatHikozakisheU･moundBulLCenterfDrOkayamacityArchaeologicaloperations,ｎｏ、 ２:19-46(ｉｎJapanese） Tin9,Ｙ，1957．TheoriginofcultivatedriceanditistransitioninChina、AcademicBuUetmofAgriculture，vol８，ｎｏ､３ （translatedmtoJapanesebyUtida,Ｊｋ.,1989ａｎｄOka,Ｈ1,1997） Zheng,Wen･Hwa.,Watabe,、,Ｓ(ｅｄ),1989.TheoriginofRicecultivationinChma・RokkouPressCo.,Ltd.,Ibkyo.(in JapanesemPanslatersareUtida,』.ｋ､ａｎｄothers.）