TurkJAgricFor 25(2001)311-317 ©TÜB‹TAK AStudyonTurkishRhododendron L.(Ericaceae) SalihTERZ‹O⁄LU,NesimeMEREV,RahimANfi‹N KaradenizTechnicalUniversity,FacultyofForestry,61080Trabzon-TURKEY Received:12.09.2000 Abstract: SomeoftheTurkishRhododendronL.taxaneedwoodanatomicalandpalynologicalstudiesfortheircertaindetermination togetherwithmorphologicalstudies.Therefore,someofthemwerestudiedandarevisedlistofthemisgiven.Newdistribution areas ofanewlyrecordedendemicvarietyof Rhododendronponticum L.( Rhododendronponticum L.subsp. ponticum var. heterophyllum Anflin)weredetermined:A7Trabzon:Maçka,A8Rize:Çaml›hemflinandA8Artvin:Murgul, inadditiontothealready knownA8Trabzon:Ofregion. Morphological,woodanatomicalandpalynologicalfeaturesofveryrarewhite-floweredspecimens ofRhododendronponticum L.werecomparedtothemaintaxaof Rhododendronponticum L.,withpurplish-pinkflowers,and Rhododendronxsochadzeae Charadze&Davlianidze,whichhasnearlythesamecoloredflowersandahairyovary.Thespecimens of Rhododendronponticum L.withwhiteflowerandanakedovary,collectedfromTurkey,werestudiedforthefirsttimefrom anatomicalandpalynologicalpointsofviewandweredeterminedtobeanaturalformofRhododendronponticum L.(Rhododendron ponticum L.subsp.ponticum formaalbum(Sweet.)Zab.). KeyWords: WoodAnatomy,Morphology,Palinology,TurkishRhododendron, Ericaceae. TürkiyeOrmanGülleri(Rhododendron L.),(Ericaceae)ÜzerineBirAraflt›rma Özet: TürkiyeOrmanGülütaksonlar›n›nkimilerikesinteflhislerininyap›labilmesiiçinmorfolojiközelliklerininyan›ndaodunanatomisi vepalinolojikyöndendearaflt›r›lmal›d›rlar.Bubak›mdan,sorunlutaksonlararaflt›r›lm›flverevizeedilmifllistesiverilmifltir .Bu taksonlardanendemikolup,yak›ngeçmifltesaptanan Rhododendronponticum L.subsp.ponticum var.heterophyllum Anflin’unA8 Trabzon:Ofyöresindenbaflka,A7Trabzon:Maçka,A8Rize:Çaml›hemflinveA8Artvin:Murgulyörelerindedeyay›ld›¤›saptanm›flt›r. Rhododendronponticum L.’unender,beyazçiçekliveç›plakovaryumlubireyleritoplanm›fl,morfolojik,anatomik vepalinolojik yöndenaraflt›r›lm›flt›r.Bubireylereaitözelliklerayn›türünmorçiçeklibireyleriilekendisineyak›nçiçekrenginevetüylü ovaryuma sahipolan Rhododendronxsochadzeae Charadze&Davlianidzebireylerikarfl›laflt›r›lm›flt›r.Beyazçiçekliveç›plakovaryumlubu örneklerTürkiye’dentoplanm›flolup, bubireylerinanatomikvepalinolojiközellikleriilkkezçal›fl›lm›fl;bireylerin Rhododendron ponticum L.’undo¤albirformu( Rhododendronponticum L.subsp. ponticum formaalbum(Sweet)Zab.)oldu¤usonucuna var›lm›flt›r. AnahtarSözcükler: OdunAnatomisi,Morfoloji,Palinoloji,TürkiyeOrmangülleri, Ericaceae. Introduction mountainregionsgrowintofairlytalltreesofabout30 Rhododendron L.oftheEricaceae isoneof thelargest minheightand100cmindiameter(SuzukiandOhba, generaofdicotyledons.AccordingtoHeywood 1988;NoshiroandSuzuki,1989). (Heywood,1978),thereareabout700speciesinthe TurkishRhododendron speciesgrownaturallyfromsea areaofChina,Tibet,Burma,AssamandNepal;almost leveltoaltitudesof2500(3100)m.Theytaketheformof 300speciesinNewGuinea;manyinJapan,tropicalAsia shrubs( R.luteum Sweet),dwarfshrubs( R.caucasicum fromIndochinatoIndonesiaandthePhilippines;whilea Pallas)andlargeshrubs(R. ponticum L., R.ungernii smallnumberoccurinEuropeandNorthAmerica.The Trautv., R.smirnovii Trautv.).Leavesevergreenor habitatsof Rhododendron speciesalsoshowawide deciduous,entireorserrate.Flowersinterminalracemes, range,fromlow-mountainforeststoalpineregionsmore usually5,occasionally6-10merous.Corollacampanulate than4000mhigh.Thespeciesareusuallyshrubsoflow and slightlyzygomorphic.Ovary6-8(5-9)-locular,stigma tomediumheight,sometimesdwarfedwithcreepingfine capitate.Fruitisasepticidalcapsule,seedswinged(Çolak, stemsinalpineregions,whilecertainmembersinlow- 1997;Davis,1978;AnflinandÖzkan,1993). 311 AStudyonTurkishRhododendron L.(Ericaceae) Inthelateststudies,allTurkishRhododendron plants whichalsohaswhiteflowers.Itispossibletoseewhite- consistof5speciesand12taxa,fourofwhichare flowered R. ponticum 500-700mabovesealevel, hybrids(AnflinandTerzio¤lu,1994;Milneetal.,1999). togetherwithmixed-deciduousforesttreesandother shrubs,especially withR.luteum. MaterialsandMethods Woodanatomicalcharacters:Tangentialvessel diameter,vesselelementlength,barnumber per Allherbarium,woodandpollensampleswere perforationplate,fiberlength,widthandwallthickness, collectedfromtheBlackSearegioninTurkey.Plant multiseriaterayheightandwidth,multiseriaterayinmm sampleswerestoredinKATOHerbarium(Karadeniz decreasewithaltitude(positivecorrelation),whilepore TechnicalUniversity,FacultyofForestryHerbarium). density(porenumber/1mm 2 incrosssection)increases WoodandpollensampleswerecollectedfromArtvin: (negativecorrelation)withaltitude(MerevandYavuz, Kafkasör,1359mabovesealevelandTrabzon:Maçka, 2000).Inthisstudy,woodanatomicalandpalynological Sümelaarea,900mabovesealevel. traitswerestudiedinsamplesobtainedfromthesame Stemsfromolderpartsoftheplantswerecutinto altitude,900mabovesealevel. piecesofca.1.5x1.5x1.5cm,andimmediatelyboiledin Genericdescriptionofwood:Wooddiffuse-porous, watertosoftenthetissuessufficientlyforsectioning. growthringboundariesdistinctorindistinct.Pores Transverse,radialandtangentialsections(20-25 evenlydistributed withoutanytendencytoaspecific micrometers)wereobtainedbyusingaslidingmicrotome pattern,numerous(pores/sq.mm),verysmalltosmall andthenthesectionswerestainedin1%aqueous (tangentialdiameters),outlineangular,solitaryand safranin.Measurementsofcelllengthwerecarriedouton sometimesradialandtangentialmultiples(2-5pore)in maceratedmaterials(Schultze’smethod)witha crosssection.Vesselelementsshort withthinwalls(1- calibratedocularmicrometer.Pollensofthepurplish-pink st 1.25microns),perforationplatesmostlyscalariformand andwhitefloweredR. ponticum werecollectedon1 sometimesbothsimpleandscalariform(only R.luteum). June1995.Pollenslideswerepreparedaccordingto Helicalthickeningpresentonthewallofthevessel Wodehouse’smethod. elementsbutinconspicuous,usuallyrestrictedtoligulate ends.Imperforatetrachearyelementsintermediateor Results libriformfibers(few),fiber-tracheids(abundant)and tracheids.Libriformfiberswithsimplepits (sometimes Inthisstudy,thepresenceofthe Rhododendron extremelyminutevestigeofborderobservedonpits, ponticum subsp.ponticum formalbumwasestablishedin sometimesinpitted). Turkey.AlltheTurkishRhododendron taxawerelistedby takingintoaccountotherstudies. Fiber-tracheidswithdistinctlyborderedpitsonthe radialandtangentialwalls.Tracheids,heredefinedas Newlydistributionareasof R. ponticum subsp. trachearyelements,resemblenarrowvesselelementsbut ponticum var. heterophyllum werefoundinA7Trabzon: lackperforationplatesoronlyhaveasingleperforation Maçka,A8Rize: Çaml›hemflinandA8Artvin:Murgul,in plateorveryreducedperforation.Parenchyma(axial) additiontoA8Trabzon:Ofregion. apotracheal-diffuse,verysparse,fusiformandstrandsof Accordingtomorphologicalstudies,itwasfoundthat 2-4cells.RaysheterogeneousI,IIorIuniseriateand R. ponticum hasflowersofdifferentcolors.Spotsof multiseriate.Crystalsnotobservedinraycellsor corollachanging fromdeeppurplish-pinktopurewhite parenchymacells(MerevandYavuz,2000). arearrangedregularly.Thecolorsofthesespotsvary Somewoodanatomicalfeatures:White-flowered R. frompinktoorange.Someindividualshavepurewhite ponticum:tangentialdiameterofvesselsis26.80 andpurplish-whiteflowers.However,purewhitecorollas microns,vesselelementlengthis550.85micronsand andfilaments haveconspicuouspurplishbases.White- fiber-tracheidlengthis702.84microns;purplish-pink floweredR. ponticum werecollectedfromA8Trabzon: floweredR. ponticum:Tangentialdiameterofvesselsis Of,Kumluderevillage,25mabovesealevel(Terzio¤lu, 25.96microns,vesselelementlengthis553.14microns, 16May1993,KATO:10206).This localityisoutsidethe fiber-tracheidlengthis693.63microns(Figures1-5). naturaldistributionareasof Rhododendronxsochadzeae, 312 S.TERZ‹O⁄LU,N.MEREV,R.ANfi‹N Figures1-5. WoodofRhododendronponticum L.-1:Crosssection;wooddiffuseporous,bigcells=vessels,smallcells=fibers,multiseriateray ontheright(x200).–2:Tangentialsection;multiseriaterayontherightandleft,procumbentcellsonthecoreofmultiseri aterays, uprightorsquarecellsontheuniseriatewingofmultiseriateraysanduniseriateraywithuprightcells(incenter),andfibercellsinvertical direction(x300).–3:Radialsection;procumbent,squareanduprightcellsintheray(x80).–4:Radialsection;scalariformperforation plate(above),uprightcellswithsimplepits(ontheright)(x500).–5:Radialsection;scalariformperforationplates(SEM, 11square =23.1microns). 313 AStudyonTurkishRhododendron L.(Ericaceae) Pollensof Rhododendron aretetradcalymmate,and DiscussionandConclusion eachofthetetradsistricolporate. Typeoftetradpollen Accordingtomorphologicalinvestigations, isspheroidandeachoneissubprolate.Textureofthe Rhododendronponticum specimenswith whiteflowers pollenistectateandtheectexineandendexinehavetwo differfromRhododendronxsochadzeae withtheirnaked layers.Sculptureisfossulateinpurplish-pink-floweredR. ovaryandpurewhiteflowers.Furthermore,these ponticum (Figures6-9), andfossulateandlisseinwhite- specimenshavesomeothermorphologicalfeatures,such flowered R. ponticum (Merev,1995),(Figures10-13). asheight,leaves,fruits,andseedsincommonwith R. Allthepollendimensionsofpurplish-pinkandwhite- ponticum withpurplish-pinkflowers.Althoughitis floweredR. ponticum weremeasured(Table1). mentionedthat R.ungernii , R. xsochadzeae haswhite Figures6-9. Pollengrainsofpurplish-pink-floweredRhododendronponticum L.(Wodehouse).–6:Opticsectionoftetrad,7-9:-porus,colpusand exineornamentationinsurfaceview(x1300). 314 S.TERZ‹O⁄LU,N.MEREV,R.ANfi‹N Figures10-13. Pollengrainsofpurewhite-flowered Rhododendronponticum L..forma album (Sweet)Zab.(Wodehouse).–10:Opticsectionof