Determination key for Central European Epilobium species based

Determination key for Central European Epilobiumspecies based on trichome morphology

Simona Strgulc Krajsek Marina Dermastia and Nejc Jogan

Department of Biology Biotechnical Faculty University of Ljubljana Vesna Pot 111SI-1000 Ljubljana e-mail simonastrgulcbfuni-ljsi Corresponding author e-mail nejcjoganbfuni-ljsi

Manuscript accepted 23 September 2006

Abstract

Strgulc Krajsek S Dermastia M and Jogan N 2006 Determination key for CentralEuropeanEpilobium species based on trichomemorphology BotHelv 116 169 ndash 178

The distribution and morphology of trichomes was investigated for 14 EuropeanEpilobium species (section synstigma) to evaluate their taxonomic relevance Threekinds of trichomes were detected Tapering trichomes without glandular activityoccurred in all examined species but differed in their distribution on the plant Blunttrichomes with a rounded tip were only present in some of the species Theywere of twotypes one of which possessed glandular activity Together trichomes characteristicsallowed a clear distinction of the 14 species and were included in a determination key

Key words Glandular trichomes micro-morphology plant taxonomy

Introduction

Epilobium (Onagraceae) is a large genus with approximately 165 species worldwide(Maberly 1993) It is divided into eight sections six of which are restricted to NorthAmerica which is the centre of diversity of the genus Only representatives of thesections Epilobium and Chamaenerion occur worldwide Chamaenerion is a sistergroup to the rest of the genus and therefore often treated as a separate genus (Baum etal 1994) with the genus name Chamerion (Holub 1972) In Europe 28 species of thesectionEpilobium are native or naturalized (Holub 1978 Raven 1980 Snogerup 1982)Haussknecht (1884) divided this section into two subsections based on the morphologyof the floral stigma Synstigma comprising all species with a cuneate stigma andSchizostigma with a four-lobed stigma The genus is considered taxonomically difficultbecause of species similarity and frequent interspecific hybridisation

BotHelv 116 (2006) 169 ndash 1780253-145306020169-10DOI 101007s00035-006-0770-yFBirkhGuser Verlag Basel 2006 Botanica Helvetica

The reliable determination of Epilobium species based on the key from FloraEuropaea (Raven 1980) or other classical dichotomous keys (Holub and Kmetova1988 Stace 1991 Fischer andAdler 1994 Smejkal 1997) requires a completely sampledplantUsually determination is not possible ifmaterial was collectedwithout organs forvegetative propagation or without ripe seeds However incomplete specimens arecommon in all herbaria which results in frequent determination errors (persexperience of the authors) Additionally in some cases even a complete specimen isnot sufficient for an accurate determination based only on macro-morphologicalcharacters

A correct determination of Epilobium species is not only important for botanicalstudies but also for pharmacological applications Recent experimental work hasrevealed that extracts of various Epilobium species have antimicrobial activity(Battinelli et al 2001) and inhibit the proliferation of human prostate cells (Vitaloneet al 2003) Some Epilobium species have already long been used in traditionalmedicine The classical drug Epilobii herba used in folk-medicine to treat variousprostate symptoms predominantly consists of fragments of stem leaves flowers andfruits of E parviflorum E montanum E roseum E collinum and other Epilobiumspecies It is mostly collected in Central Europe former Yugoslavia and Romania(Bisset andWichtl 1994) For an accurate identification of suchmaterial determinationkeys based on the macro-morphological characteristics are useless and other micro-scopic traits should be applied instead

Trichomes have already been considered as an important additional micro-morphological character for distinguishing problematic Epilobium species (Holuband Kmetova 1988 Stace 1991 Fischer and Adler 1994 Smejkal 1997) Within thegenus glandular and tapering trichomes have been described (Saukel 1982) and adetermination key based on micro-morphological features including trichomes hasbeen developed for the genus Chamerion and the subsection Schizostigma (Saukel1983a b) However no determination key is available yet for the majority of EuropeanEpilobium species from section Synstigma

The aims of the present studywere (1) to obtain quantitative and qualitative data ontrichomes of about 60 of the European Epilobium species which are widespread inSouthern and Central Europe (2) to evaluate their taxonomic significance and (3) topropose a determination key based on the results

Materials and Methods

The following taxa of Epilobium from Southern and Central Europe wereinvestigated E alpestre E alsinifolium E anagallidifolium E ciliatum E collinumE hirsutum E lanceolatum E montanum E nutans E obscurum E palustre Eparviflorum E roseum E lamyi and E tetragonum s str The plant material wascollected in Slovenia only specimens ofE lanceolatumwere from Italy and Serbia Allvoucher specimens are deposited in the herbarium LJU (Ljubljana Slovenia)

Trichome micro-morphology was studied on a total of 250 specimens from thevarious species The density of trichomes was estimated using stereomicroscope with45x magnification on the following parts of plants (1) stem middle (2) stem in theregion of the inflorescence (3) adaxial surface of the leaf nearest to the stemmiddle (4)adaxial side of the central vein of the same leaf (5) margin of the same leaf (6) calyxand (7) fruit For each part density was classified in one of four classes no trichomes

170 Simona Strgulc Krajsek Marina Dermastia and Nejc Jogan

few trichomes seen occasionally trichomes regularly present surface densely coveredwith trichomes

For measurements of trichome length pieces of surface tissue were cut from leavesstems and fruits of selected herbarium specimens Wrapped in a filter paper the tissuewas boiled in water for 10 min transferred to 16 HNO3 for 5 min and thensuperficially dried on a paper towel It was further transferred to 5NH4OH for 5minagain superficially dried on the paper towel and then washed in running waterMaterial was stored in water overnight On the next day the epidermis was removedfrom the pieces of plant tissue and semi-permanent slides for light microscopy weremade using glycerine gelatine The trichome lengths were measured using lightmicroscopy (microscope Carl Zeiss with digital camera CCD Sony DXC-950P or AxioCam MRc Carl Zeiss Vision) and computer program KS 400 or Axiovision 31 forimage analysis (Carl Zeiss Vision) On every slide up to 20 simple and 20 blunttrichomes were measured

For scanning electron microscopy (SEM) of trichomes on fresh plant material ofEpilobium hirsutum pieces of leaf stem and fruit tissue were fixed in 1glutaraldehyde and 04 formaldehyde in a 01 M cacodylate buffer Later theywere washed in a 01 M cacodylate buffer dehydrated with ethanol and then dried in acritical point dryer Samples were coated with gold and observed with an scanningelectron microscope (JEOL 840A JEOL Ltd Japan)

The glandular activity of trichomes was observed with a stereomicroscope on freshmaterial of Epilobium hirsutum and E parviflorum collected in the field in LjubljanaSlovenia (voucher specimens are deposited in the herbarium LJU numbers 10020418and 10033317)

The determination key was tested on herbarium material from herbaria M MSBWU ZA ZAHO and SOM an unequivocal determination was possible in all cases

Results and discussion

Trichome morphology and glandular activity

Two types of trichomes were easily recognized in both fresh and herbariumEpilobium material tapering trichomes with gradually tapering apices and blunttrichomes with rounded tip (Fig 1) Tapering trichomes were simple and unicellularwith usually partly papillose surface They were appressed or patent and differed inlength and curvature Obviously they did not have any glandular activity Blunttrichomes were unicellular and of two types The most common type was long andpatent (Fig 1a) and possessed a glandular activity visible on fresh material as smalldroplets of exudates on the trichome apices (Fig 2a) After exudate secretion a scarremained on the apex The second type of blunt trichomes had a similar basic shape butit was always shorter and tightly appressed to the epidermis (Fig 1b) no glandularactivity was detected

To our knowledge this is the first direct observation of glandular activity ontrichomes of the genus Epilobium although some authors had previously describedtrichomes of the blunt type as glandular and the simple tapering ones as non-glandular(Saukel 1982 Fischer and Adler 1994 Smejkal 1997)

Botanica Helvetica 116 2006 171

Distribution and density of trichomes

Simple tapering trichomes were present in all 14 Epilobium species (Tab 1) buttheir distribution differed among species In general the upper parts of plants withinflorescences calyces and fruits were more densely covered with tapering trichomesthan the lower parts The exceptions were E hirsutum which possessed only fewtapering trichomes on the upper parts and E parviflorum without tapering trichomeson the upper parts

In all studied species from the Synstigma group except for E lamyi and E palustrethe tapering trichomes were arranged on stems in longitudinal rows Between rowsstems were glabrous These trichome rows were not present in inflorescences Thedistribution and density of tapering trichomes were similar in calyces and fruits

Fig 1 Lightmicrography of (a) stem epidermis ofEpilobium montanum showing tapering andblunt trichomes typical for many Epilobium species and (b) fruit epidermis of Epilobiumcollinum showing blunt trichomes typical for Epilobium collinum and E obscurum

Fig 2 Blunt trichomes on stem of E hirsutum (a) Small droplets of exudates on the trichomeapices visible on fresh material showing the glandular activity of cuneate trichomes (b) SEMmicrography of blunt trichomes


The density of blunt trichomes was also greater on upper plant parts than on lowerparts Their distribution and density was similar on the epidermis of inflorescencescalyces and fruits (Tab 2) but differed between young andmature leaves In some of the14 Epilobium species scattered appressed blunt trichomes were present only on veryyoung leaves and completely absent from mature leaves (Tab 2)

Long and patent blunt trichomes were characteristic for Epilobium alpestre Ealsinifolium E anagallidifolium E ciliatum E hirsutum E montanum E nutans Epalustre E parviflorum andE roseum (Figs 1a 2 Tab 2) Shorter and appressed blunttrichomes were detected only in E collinum and E obscurum Especially on the fruitsof these two species the blunt trichomes were often densely covered by tapering tri-chomes and therefore almost imperceptible E tetragonum s str and E lamyi did nothave any blunt trichomes

Trichome length

The length of tapering trichomes ranged between 006 and 21 mm The longesttrichomes with a length over 1 mm were detected on the epidermis of E hirsutumHowever over 04 mm long trichomes were also present in E parviflorum All otherspecies had similar distributions of trichome lengths (Fig 3a)

Blunt trichomeswere generally shorter than tapering ones with length between 006and 036 mm (Fig 3) The shortest blunt trichomes were present in E collinum(Fig 3b) while the longest ones were present inE parviflorum E collinum is the onlyspecies that reliably differs from many other Epilobium species in length of blunttrichomes (Fig 3b)

Tab 1 Distribution of tapering trichomes on selected parts ofEpilobium plants Symbols indicatethe trichome density and arrangement no trichomes few trichomes may be seen occasio-nally + trichomes present ++ surface densely covered with trichomes L trichomes arranged inlongitudinal rows

Species Stem Inflorescence Adaxialleafsurface

Central vein onadaxial side ofleaves

Leafmargin

Calyx Fruit

E alpestre L+ ++ ++ ++ ++ ++E alsinifolium L+ ++ + + + +E anagallidifolium L+ ++ + E ciliatum L+ ++ ++ + +E collinum ++ ++ ++ ++ ++ ++E hirsutum ++ + + ++ ++ + +E lanceolatum ++ ++ ++ ++ + ++E montanum ++ ++ ++ ++ + ++E nutans L+ ++ + ++ ++E obscurum L+ ++ + ++ ++ ++E palustre ++ ++ ++ ++ ++ ++ ++E parviflorum ++ ++ ++ ++ E roseum L+ ++ ++ ++ ++ ++E lamyi ++ ++ + ++ ++ ++E tetragonum s str L+ ++ ++ ++


Evaluation of taxonomic relevance

Simple tapering trichomes and two types of blunt trichomes were found in all stu-died European taxa of Epilobium Although the length of tapering trichomes is afrequently used character in determination keys (Raven 1980 Holub and Kmetova1988 Stace 1991 Fischer and Adler 1994 Smejkal 1997) the present study revealedthat the general presence and similar length of tapering trichomes makes these traits

Tab 2 Distributionof blunt trichomes on selected parts ofEpilobiumplants Symbols indicate thetrichome density and arrangement no trichomes few trichomes may be seen occasionally+trichomes present ++ surface densely covered with trichomes L trichomes arranged in longi-tudinal rows appressed type of blunt trichomes

Species Stem Inflorescence Fruit Calyx Adaxial leaf surface

E alpestre ++ ++ ++ E alsinifolium + + + E anagallidifolium ++ + E ciliatum + ++ ++ + E collinum + + + + +E hirsutum ++ ++ ++ ++ +E lanceolatum + ++ ++ ++ +E montanum + ++ ++ ++ +E nutans + + E obscurum + + E palustre + ++ + E parviflorum ++ ++ ++ E roseum ++ ++ + E lamyi E tetragonum s str

Fig 3 Length of (a) tapering and (b) blunt trichomes ofEpilobium species frommeasurementson numerous herbarium specimens Boxes indicate first quartile median and third quartile thevertical lines extend up to the 5th and 95th percentiles Other symbols average x 1st and 99thpercentile minimum and maximum Distributions are based on pooled data from measu-rements on stems fruits and leaves


unsuitable as a discrimination criterion among EuropeanEpilobium species Howevertheir distribution on the plant can be used for determination In contrast the di-stribution and types of blunt trichomes proved to be reliable additional characters forthe proper determination within the genus In particular the shortest blunt trichomesamong the examined Epilobium species can be used as a character for distinguishingamong the frequently misidentified species E montanum and E collinum Likewisethe length of blunt trichomes can be applied for the discrimination between E ana-gallidifolium and E alsinifolium species that grow in similar habitats Two pairs ofEpilobium species E roseumE alpestre and E montanumE lanceolatum do notdiffer in trichome distribution abundance and length but differ in many macro-mor-phological and ecological characters

Some methodic problems may occur E collinum and E obscurum have blunttrichomes that can be easily overlooked Especially inE obscurum the blunt trichomesare often hidden under a dense indumentumof tapering trichomes The blunt trichomesare best visible with stereomicroscope (20M magnification) on the calyx and fruitAdditionally it is important to know that only mature leaves are appropriate for tri-chome observations because they are the only ones with fully developed trichomes Thepresence of long patent blunt trichomes can be detectedwith unaided eye especially onfresh material For a detection of the appressed type a hand lens with minimum of 15Mmagnification is needed

Conclusions

Overall the length distribution and abundance of the trichomes prove to be usefulcharacters for a reliable discrimination among Epilobium species and may help toresolvemany problems with the determination of morphologically very similar speciesIt is possible to identify incomplete specimens eg plants before flowering plants inlate autumn after flowering incomplete specimens from herbarium collections andfragments of plants in drugs using a determination key based on the trichome charac-ACHTUNGTRENNUNGteristics The key also enables to avoid a time-consuming preparation of dry flowersOur results encourage further research with additional species and the extension of thestudy to hybrids in the genus

Zusammenfassung

DieAnordnung undMorphologie derHaare von 14 europGischenEpilobiumArtenwurde untersucht um ihre taxonomische Bedeutung und Eignung als Bestimmungs-merkmale zu beurteilen Drei verschiedene Haarformen wurden ermittelt SpitzeHaare ohne glandulGre AktivitGt kamen bei allen NberprNften Arten vor aber es gaboffensichtliche Unterschiede bezNglich ihrer Verteilung auf der Pflanze Die abge-rundeten Haare waren entweder gerade abstehend oder an der Basis gekrNmmt Nurdie abstehenden Haare hatten eine DrNsenfunktion Die abgerundeten Haare warennicht bei allen NberprNften Epilobium-Arten vorhanden Die beobachtetenMerkmaleermccedilglichten eine eindeutige Unterscheidung der meisten untersuchten Epilobium-Arten und wurden in einem BestimmungsschlNssel zusammengefasst


This work was supported by the Ministry of Education Science and Sport Republic of Slovenia (grant NoS4-487-0012124102000 awarded to SSK) and the Slovenian Research Agency (grant No P1-0212) Theauthors thank Dr Kazimir Draslar for scanning electron micrographs of Epilobium trichomes Dr AndrejBlejec for discussion about statistical analyses and Dr Ales Kladnik for help with the preparation of figures

References

Battinelli L Tita B Evandri MG andMazzanti G 2001 Antimicrobial activity ofEpilobiumspp extracts Farmaco 56 345 ndash 348

Baum DA Sytsma KJ and Hoch PC 1994 A phylogenetic analysis of Epilobium (Ona-graceae) based on nuclear ribosomal DNA sequences Syst Bot 19 363 ndash 388

Bisset NG and Wichtl M (eds) 1994 Herbal drugs and phytopharmaceuticals A handbookfor practice on a scientific basis Medpharm Scientific Publishers CRC Press Stuttgart

Fischer MA and Adler W 1994 Weidenrccedilschen Epilobium In Fischer M (ed) Exkur-sionsflora von Psterreich Ulmer Wien 489 ndash 493

Haussknecht C 1884 Monographie der Gattung Epilobium Fischer JenaHolub J 1972 Taxonomic and nomenclatural remarks on Chamaenerion auct Folia Geobot

Phytotax 7 81 ndash 90Holub J 1978 Epilobium komarovianum Leveille Ceskoslovensku Zpr C Bot Spolec 13

77 ndash 85Holub J and Kmetova E 1988 Epilobium L In Bertova L (ed) Flora Slovenska IV4

VEDA Bratislava 433 ndash 489Maberly DJ 1993 The plant book A portable dictionary of the higher plants Cambridge

University Press CambridgeRaven PH 1980 Epilobium L In Tutin TG (ed) Flora Europaea 5 Cambridge University

Press Cambridge 308 ndash 311Saukel J 1982 Pharmakobotanische Untersuchungen von Arzneidrogen IIHerba Epilobii 1

Mitteilung Sci Pharm 50 179 ndash 200Saukel J 1983a Pharmakobotanische Untersuchungen von Arzneidrogen II Herba Epilobii

2 Mitteilung Sci Pharm 51 115 ndash 132Saukel J 1983b Pharmakobotanische Untersuchungen von Arzneidrogen II Herba Epilobii

3 Mitteilung Sci Pharm 51 132 ndash 156Smejkal M 1997 Epilobium L Evrbovka In Slavik B (ed) Kvetena Ceske Republiky

Academia Praha 99 ndash 132Snogerup S 1982 A new species of Epilobium (Onagraceae) from Northern Greece Wil-

denowia 14 227 ndash 229Stace CA 1991 New Flora of the British Isles Cambridge University Press CambridgeVitaloneAGuizzettiM Costa LG andTitaB 2003 Extracts of various species ofEpilobium

inhibit proliferation of human prostate cells J Pharm Pharmacol 55 683 ndash 690

Appendix Dichotomic determination key for Central European Epilobium speciesusing trichome morphology

The following determination key for Epilobium species is based only on the pre-sence of trichome types their distribution and length It is applicable for the determi-nation of incomplete plant material or when only a single specimen is available Astereomicroscope with 20M magnification is needed for a reliable determination

All native species of Epilobium from Central Europe and the widespread natur-alizedNorthAmerican speciesE ciliatum are included in the determination key so it isappropriate for determination of Epilobium species in Central Europe Two species


from the Balkan Peninsula E gemmascens and E vernonicum and one from westernEuropeE duriaei are not included in the determination key All three species are rareand can be found only in small local populations at high altitudes

The determination key does not include species from genusChamerion (Epilobiumsect Chamaenerion) They can easily be determined using macro-morphological cha-racters and a determination key based on micro-morphologicalcharacters has alreadybeen published by Saukel (1983a)

1 Plant completely without obvious patent blunt trichomes 21 Plant with visible patent blunt trichomes 52 Plant covered only with tapering trichomes 32 Plant covered by at least some very inconspicuous ap-pressed blunt trichomes present on the fruit andor calyxandor adaxial leaf surface

4

3 Stem uniformly covered with tapering trichomes leafmargins and primary vein pubescent

E lamyi

3 Stemglabrous (but can be pubescent in the inflores-cence) only few trichomes on the longitudinal ridgesleaves glabrous

E tetragonum s str

4 Stem trichomes arranged in longitudinal rows adaxial leafsurface of young leaves without appressed blunt trichomesblunt trichomes on the calyx and fruit 010ndash016 mm long

E obscurum

4 Stem uniformly covered with tapering trichomes adaxialleaf surface of young leaves with some appressed blunttrichomes blunt trichomes on the calyx and fruit 008ndash011mm long

E collinum

5 Adaxial leaf surface densely covered with tapering tri-chomes

6

5 Tapering trichomes on the adaxial leaf surface absent orpresent only on the veins andor leaf margin

8

6 Upper part of plant without tapering trichomes but denselycovered with the blunt trichomes

E parviflorum

6 Upper part of plant with tapering and blunt trichomes 77 Some tapering trichomes longer than 1 mm E hirsutum7 All tapering trichomes shorter than 05 mm E palustre8 Stem uniformly covered with trichomes 98 Stem trichomes arranged in longitudinal rows 119 Some tapering trichomes longer than 1 mm E hirsutum9 All tapering trichomes shorter than 05 mm 1010 Blunt trichomes on the calyx fruit and stem frequent and

patent 010ndash017 mm longE montanum or Elanceolatum

10 Blunt trichomes on the calyx fruit and stem short ap-pressed and inconspicuous 008ndash011 mm long

E collinum

11 Adaxial side of the central leaf vein glabrous 1211 Adaxial side of the central leaf vein at least with some tri-

chomes14

12 Fruit densely covered with tapering trichomes 1312 Fruit covered only with some tapering trichomes and more

numerous blunt trichomesE anagallidifolium


13 Upper part of plant and fruit densely covered with the blunttrichomes

E ciliatum

13 Upper part of plant and fruit with scattered blunt trichomes E nutans14 Leaf margin glabrous E anagallidifolium14 Leaf margin pubescent 1515 Short appressed and inconspicuous blunt trichomes pre-

sent only on the calyx and fruitE obscurum

15 Blunt trichomes longer patent and present on all upperparts of plant

16

16 Calyx and fruit with scattered tapering and blunt trichomes E alsinifolium16 Calyx and fruit densely covered with tapering and blunt

trichomesE alpestre or E ro-seum


The reliable determination of Epilobium species based on the key from FloraEuropaea (Raven 1980) or other classical dichotomous keys (Holub and Kmetova1988 Stace 1991 Fischer andAdler 1994 Smejkal 1997) requires a completely sampledplantUsually determination is not possible ifmaterial was collectedwithout organs forvegetative propagation or without ripe seeds However incomplete specimens arecommon in all herbaria which results in frequent determination errors (persexperience of the authors) Additionally in some cases even a complete specimen isnot sufficient for an accurate determination based only on macro-morphologicalcharacters

A correct determination of Epilobium species is not only important for botanicalstudies but also for pharmacological applications Recent experimental work hasrevealed that extracts of various Epilobium species have antimicrobial activity(Battinelli et al 2001) and inhibit the proliferation of human prostate cells (Vitaloneet al 2003) Some Epilobium species have already long been used in traditionalmedicine The classical drug Epilobii herba used in folk-medicine to treat variousprostate symptoms predominantly consists of fragments of stem leaves flowers andfruits of E parviflorum E montanum E roseum E collinum and other Epilobiumspecies It is mostly collected in Central Europe former Yugoslavia and Romania(Bisset andWichtl 1994) For an accurate identification of suchmaterial determinationkeys based on the macro-morphological characteristics are useless and other micro-scopic traits should be applied instead

Trichomes have already been considered as an important additional micro-morphological character for distinguishing problematic Epilobium species (Holuband Kmetova 1988 Stace 1991 Fischer and Adler 1994 Smejkal 1997) Within thegenus glandular and tapering trichomes have been described (Saukel 1982) and adetermination key based on micro-morphological features including trichomes hasbeen developed for the genus Chamerion and the subsection Schizostigma (Saukel1983a b) However no determination key is available yet for the majority of EuropeanEpilobium species from section Synstigma

The aims of the present studywere (1) to obtain quantitative and qualitative data ontrichomes of about 60 of the European Epilobium species which are widespread inSouthern and Central Europe (2) to evaluate their taxonomic significance and (3) topropose a determination key based on the results

Materials and Methods

The following taxa of Epilobium from Southern and Central Europe wereinvestigated E alpestre E alsinifolium E anagallidifolium E ciliatum E collinumE hirsutum E lanceolatum E montanum E nutans E obscurum E palustre Eparviflorum E roseum E lamyi and E tetragonum s str The plant material wascollected in Slovenia only specimens ofE lanceolatumwere from Italy and Serbia Allvoucher specimens are deposited in the herbarium LJU (Ljubljana Slovenia)

Trichome micro-morphology was studied on a total of 250 specimens from thevarious species The density of trichomes was estimated using stereomicroscope with45x magnification on the following parts of plants (1) stem middle (2) stem in theregion of the inflorescence (3) adaxial surface of the leaf nearest to the stemmiddle (4)adaxial side of the central vein of the same leaf (5) margin of the same leaf (6) calyxand (7) fruit For each part density was classified in one of four classes no trichomes




















Trichome length






Leafmargin

Calyx Fruit












Conclusions


Zusammenfassung




References
























4


E lamyi


E tetragonum s str


E obscurum


E collinum


6


8


E parviflorum




E collinum


chomes14





E ciliatum




16






















Trichome length






Leafmargin

Calyx Fruit












Conclusions


Zusammenfassung




References
























4


E lamyi


E tetragonum s str


E obscurum


E collinum


6


8


E parviflorum




E collinum


chomes14





E ciliatum




16












Trichome length






Leafmargin

Calyx Fruit












Conclusions


Zusammenfassung




References
























4


E lamyi


E tetragonum s str


E obscurum


E collinum


6


8


E parviflorum




E collinum


chomes14





E ciliatum




16






Trichome length






Leafmargin

Calyx Fruit












Conclusions


Zusammenfassung




References
























4


E lamyi


E tetragonum s str


E obscurum


E collinum


6


8


E parviflorum




E collinum


chomes14





E ciliatum




16













Conclusions


Zusammenfassung




References
























4


E lamyi


E tetragonum s str


E obscurum


E collinum


6


8


E parviflorum




E collinum


chomes14





E ciliatum




16






Conclusions


Zusammenfassung




References
























4


E lamyi


E tetragonum s str


E obscurum


E collinum


6


8


E parviflorum




E collinum


chomes14





E ciliatum




16





References
























4


E lamyi


E tetragonum s str


E obscurum


E collinum


6


8


E parviflorum




E collinum


chomes14





E ciliatum




16







4


E lamyi


E tetragonum s str


E obscurum


E collinum


6


8


E parviflorum




E collinum


chomes14





E ciliatum




16





E ciliatum




16




Documents

Determination key for Central European Epilobium species based