J. Plant Anat. Morph. Vol. 7 No. .1, pp. 9-19Scientific Publishers. Jodhpur (India), 1997

MORPHOLOGICAL AND ANATOMICAL STRUCTURE OF THE CYPSELAS OF

SOME SPECIES OF THE TRIBE EUPATORIE,AE (ASTERACEAE)

SosHnN Kn. MuxHPRJEE & A.K. SlnrnnDept. of Botan\', Universih' of Kctlt'ani, Kalt'ani, Nadicr - 74I 235 W Bengal

ABSTRACT

The cypselas of seven species under three generit (Eultatorium, Liatris nd Mikania\ are studied rnorphologically

and anatomically by SEM antl light rnicroscopy. According to SEM, some morphological t'eatures of the cypselas are

diacritical fbr sorne taxa. Structure of trichome, bordered pit-like phytornelan ring, stylopodium, carpopodium ancl

pappus bristles are studied in detail. The pericarp is clearly distinguished into two zones. A unique resinous continttousp; cliscontinuous ring of phytomelan layer is found within the pericarp. Testa is usually undil'tbr:entiated except in

Liatris. Structure of endosperm is not significant taxonomically. An artiflcial key to the species is prepared based on the

olrservcd f'catulcs of these cvpselas.

INTRODUCTION

An cxtensive systelnatic revision of the tribe

Eultcrtoricuc has bcen done by Robinson and King(1911). In nrajority of the earlier stLrdies, a brieferomor;lhic teatures 01' cypselas have heen

inclLrded, except the work ol' Blake (19281 who

only has described in details the external

morpholo-eical f'eatures of cypselas o1' sotlte

Astcraccac. Sirnilarly little attention has been paid

to the anatornical f'eatures of cypselas of the tribe

Enpotoricue in the earlier works fbr identificationpurposes. The only exception is a coritribution by

Pandey and Singh (1919). f'hercfbt'e, an extensive

colnparative morphologrcal and anatomical studles

of cypselas are neccssaLy 1or proper characteri-

zation of these taxa.

The objective of the present study is two fold;first. to desclibe tlte exontorphic and anatotnical

features <rl' cypselas of seven spccics of the tribe

Eultcttoriaue; sec:ond. to contpare and idcntify the

species based ott observecl chat'actet's.

This paper is concet'tted rvith three genera

belonging to three groups i.e. Ertpttloriinat, Liatris

-urcrup ancl Mikania, group whioh are potential

subtribes among the l9 groulls done by Robinson

and King (1.c.).

MATERIALS AND METHODS

Seven species uncler three genera

(Eupatoriunt, Lintris'. M ikanin) were int,esti-eated

with respect to their cypselar structure. These are

listed in Table L Mature dLy cypsclas were.

obtaineil from four Herbalia ol' thc world, i.e..

Queensland Herbarium, Queensland, Australia(BRI); Jardin Botanico do Rio de Janeiro, Brazil(RB); The Herbariurrr. Dept. of Botany, NationalTaiwan University, Taiwan, Republic of China(TAI); Botanischer Garten der Universitat Zurich.Zurich, Switzerland (Z), Some cypselas were

preselvecl in FAA. For morphological study. ten

randomly selected cypselas lionr dry, FAApreset'ved and NaOH (l-5Vr,) cleared were takcn

fionr each collection. Fot' histological studlr,

softened mature cypselas wer-e sectioned by

nricrotome (standard paraffin methods) and by hand

with the help of sharp razor blacle. In majority otthe spec'ies, it was r,ery dil'ficult to cut transverse

section in microtonre as the cypselas have a thickbrittle, black. phytontelln liryer. Tltelefore, at least

ior this group hancl section is suitablc for'

anatonical study. Sections were statned in safianin

fast green contblnation. For the proper

identification o1- the vascular bundles in thc

pericarp, cypsclas wcre clearecl and staitted in Io/c

Mukherjee & Sarkar

Eupatorium cttrutabiruunL. Z

E. chinense L- var. tozatTense TAI(Hay.)Kitamura

E. forntosanumHay. TAI

basic fachsin solution in l}Va KOH after WILCOX(1977). Cypselas were processed followingstandard method for SEM and thephotomicrographs were taken fiom RSIC, Bose

Institute, Calcutta and USIC, Burdwan University.Terrninology is self- explanatory and followsKynclova (1970).

Table 1. DifTerent taxa of the tribe Eupatctrieae.

Taxa Source CollectionNo.

lrorizontally oriented phytomelan plates. Borderedpit-like phytomelan rings have been noted by Robinsonand King (1.c.).

The structure of stylopodium is more or less

uniform in most of the studied species. The stylopodiumis usually narrow or wide cylindrical tube like stlucture.

Robinson and King (1977) have reported that inEqtatoriwn the carpopodiun is poorly difl'erentiated orunditl-erentiated hut it has been observed that walldeveloped carpopodium with thick walled cells exist rn f.riparium (Fi-c. 2H) and E. vitalbae (Fig. 2N), whilepoorly developed carpopodia are noticed in other three

species of Eupatoritrru. A cup like carpopodium wrth

unequal labes at the base is seen in Mikanis (Fig. 30). InE. chilrcnsc vat. toaonense (Fig. 1J) the lowermost row ofcells in corpopodiurn is differentiated. Similar type ofstructure has been reported by Robinson and Kin.e (1.c.)

in other genera (Ayaparu4 Ayapanopsis) of this tribc. Inall the studied species carpopodia are complete ring likein appearance, Haque and Godward (1984) heve also

reported the presence of conplete rrng like carpopodia inother species rn the tribe Ettpoiorieae.

Pappus bristles alc uniseriate and usually thin,scahrous, persistent and united in a narrow or wide lingexcept in Liotris tFig. 3E), rvhere the bristles are thick.biseriate and subplunose to plutrose type.

SEM studies of cypselas provide rnany interesting

t-eatures of which some are mentioned below ; I In E..

formosanurn (PM- lD), glandular trichomes are distinctlypedicellate. Cells of the pedicel are arranged in two rows

with a terminal bulbous gland. 2. ln E. c:cumabinunt

(PM-lB) cypselar .[lands are sessile, dome shaped and

sub globose with nearly srnooth surface. 3. ln Liatrispappus Lrnstles are biseriate and plumose to subplumose.

Main axis of the bristle is multi-channelled (PNI-lH).Surface of the twin hair is nricro-papillate type (PM-1G).

Micropapillate type of trichomes have been observed inmany members of Brusslcaceae by Barthlott (1981). 4.

Twin hairs near the ribs in I or 2 rows, acroscopic withunequal short cells are tbund in E. ripcu'iunr (PM-lE).

Cvltselar Anatonty

Anatomically the pericarp o1'the tnbe [iultatnritatcould be distingurshed into three cltegoriescorresponding to the gettera o[ groups. Nevertheless the

basic sttuctural pattern of tlte pericarp is more or less

identical in all the species.

Pericarp may be moderately thick in liupntorilurt(Fig. 4A2, 82; -5A2, 82, Cl) and Litttris (Fig' 6.{2) oL

tlrick in Mikatiu (Fig, 682). Pericarp is clearlY

distinguishcd into two zones.

Epicarpic cclls are uniseriate, parenchymatous and

Nr. 392

Y.F. Chen

3898

Y.F. Chen

3819

SN 252

Nr,4l4SN 253

E. ripariwn Regal

E. vitqlboe DC.

Liai ri s s p ic a ta\N illd.

Mikanh trinervis Hook. et Clus.

BRI

RB

Z

RB

OBSERVATIONS AND DISCUSSION

Ct'1t s c I ar M o t'p h o I o g:'

ln Etqtatorieae lhe cypselas are homotnorphic,

usually oblong or oblanceolate, either tapered at base or

at both ends. Cross section of cypsela usully sltows fiveprominent ridges in Eupatoriunr (Fig.4A1, Bl;5A1, Bl)but they are inconspicuous in !l4ikaniq (Fig. 68l) whichis pentangular.ln Liatris, (Fi-e. 64l) cypselas are lnore or

less circular with ten prominent ribs.

Cypsela surface usually bears dilferent types oftrichomes. Trichomes may be glandular or non glandular

type. Each species bears only one type of trichome. Twintypes of hairs are fbund in E, ripariunr. (Fig. 2FG), f'vitalbae tFig. 2K), Liatris, (Fig. 3D) while rest of the

species possess glandular trichotnes. Unbranched,

multicellular, filamentous, and non glandular trichome is

found only in E. rfitariwn, (Fig. 5B4) whereas glandular

uniseriate, unbranched, multicellular with terminal

glandular cells and subsessile subglobose vesiculate type

trichome is tbund in Mikania (Fig.3 M,N). A unique type

(biseriatc c:apitate) of glandulaL trichome is noticed in E.

fornrosrnturr (Fig, IST). Sahu t1984) has lepofted the

above typed (except uniseriate non glandular type) of

hairs lrom the genus Erqtatoriunt.

Atier clearing the cypselar wall, surf-ace shows

nuurerous bordered pit-like phytomelan dn-es which are

usually systentatically arranged in several vertical rows,

except in Liatris (Fig. 3C) where lhe wall surlace shows

10

J. Plant Anat. Morph. Vol.7 No. l, lg97

Figurel.A-E. ErytatoriumcannetbinumL.A.Cypsela;B.Cypselarapicalpartshowingstylopodium;C.Cypselarbasalpart showin.g carpopodium and carpopodial projection; D. Cypselar wall after clearing; E. Apical parl of pappusbristle; F-L. E. chinenseL. var, tozcutense (Hay.) Kit. F. Cypsela; G- Cypselar apical part; H. Cypselar basalpart;I. Cypselar wallafier clearing;J. Carpopodial cells; K. Cypselar basal part after clearing; L. Middle parr of pappusbristle. M-T. E. fonnosuttum Hay. M- Cypsela;N- Cypselarbasal part; O- Cypselar aprcal parl; P. Cypselarwallaticr clearing; Q- Part of pappus bristle; R- Cypselar vascular traces. S,T- Cypselar glandulirr hlirs.

WL

o lJ.P'

/ff

11

Mukheriec $ Srrrftai

ff-!grfiirlB

Figure 2. A-H. Eqtarcriwn rilturiturtR-egel, A- Cypsela; g -cyrylotjurlace;

c- cypselar wall al'tet cle aring; D- Basrl

part ot pappus t,ririi.r;'Ll Apical fiart "f pJ;p*l*u.; F,c cypselar twin liairs; H- carpopodiat cells' I-o' f'

t'talbocDC. l- Cypsela; J- Cypseta ort., ,r.tIJ1-'.,r poppura K- Clpselar twin hair; L- Bnsal part oi pappus bristlcs;

Ivl- cypsetar rvall after c.learing: N- CaLpopodial cells: o- Part of pappus bristle

12

J. Pl.ant Anat. Morph. Vol. 7 No. l, 1997

J.o-o-x-o'3 A

Figure 3. A-C. Liatris spicaraWilld. A-Cypsela; B- Cypselar surface; C- Cypselar wall after clearing; D- Cypselar twtn

harr; E- part of pappus brrstle; F- Ciipopoclial cells; G- CypselaL wall showing nb & furrows atier clearing. H-P.

Mikrmiutritrervis iiook. et Clus. H- Cypsela; l- Cypselar wall after clearing;J- Papprrs bristle; K- Apical part of

pappus bristle; L- Basal part of puppur 6ristle; M- Cypselar unbranc:hed multicelluar hair; N- Cypselar subsessile

veiictrlate hair; o- carpopodiurn (diagramrnatic): P- carpopodial cells'

.rI

Ir(r

:l,t

I

13

-zPPL

g artfta: rji:t +& $eii*r:ir'

)- _--__;

I- FP'Pt! s'cL I__ scL

T

Jt'

J"E

-'c()

ceqpn)PT

PA-SCL8

-O-Z-nl-. Ar.tll,tl4.QO25 a2,Al.B?.H1,p15,,86,87

' Figure 4. Cross scciion of cvpselas.

Al-A3. Eupatorium catunbinun L. Al- Diagrammatic A2- A part ol cypselar rvall at the rib; A3- Cypselar

_clanclularhait.Bl-B7. E.chinenscL.var.toianensc(Hay.)Kit.Bl-Diagrammatic; B2-Apartof c1'pselarwall ltllrr: f uu'ow; B3-A part of cypsclar wall at the rib; 84- Cotyledons & testa; B5-87- Glandular hairs of cypsela,

14

.1. Plant Anat. Morph. Vol. 7 No. I, tggT

-o ,-t1- -- a,o-o25 -_82.85.84,E}5,C I

o-2 - Ato o25 - a4.a5,a6,a 7

.oo? - A2.a3

A I -A7 - Dupcttoriunt.fonrrosununrcndospenn;

'A4 At iypserar grana .rJii,il,x#,,1lJlI.i'?i-,;iTJi.1cypselar wall at the rib; 83-85- Cyps cypselar wall a*he rib.

rrore or less unifbrm throughout cxcept iu Euparoriurnriparium, (Fig. 5 B2) where 2-3 coiourless enlargedperenchyma cells are lbund at the tip ol'each rib. Outermesocarpic zone is quite distinct in thrce seneta,

Hypodelmal uniseriate plrenchyrnatous cells maybe present as in E, chinense (Fi.g. 48i, 83) or absent in

discrete bundles; 'uvhereas in Mikcmiu (Fig. dB2)hypodermal mesocarpic zone is very ra,ide and inade up

Accordin-cs to Crau (19g0), ',in some tribes thelnteguments de-uenerate by tbrming a testa ol a collapsed

15

Mukheriee & Sorknr

o-{rrnr -

-@l*-ci1l - -r':.9-95 . az

Figute 6' Cross section of-cypselas

Al,A- Liatrisspicqtawilld.A niugiur*"utrc;nr-npaftof;i;selarwall'Bl '82-Mikuniatrineruis Hook'et

Clus. Bl- Diagrammatic;82- A

led bY genes.

ffiffi*'ffi: coNcLUSro

of the

genus

an the

l, Bl; 5Al' Bl)' Eunatoriunt and ' of l0

id of crystals as ,iUr, tt i.t plumose to subplumose biseriate pappus

bristles' cypselar wall surface with horizontally

On the basis of presence of conttnuous or

16

,les

icaItonin

rpus

ally

the

nus

the

l0

J. Plant Anat. Morph. Vol.7 No. I, 1997

PM.l. A-H. SEM survey of cypselas.A, B- Eupatoriwn cannabinum L. A- Cypsela, x 50; B- Surtace sessile gland, x 1600. C,D- Eupatoriwnfornqsanum Hay. C- Cypsela, x 50; D- Pedicellate glandular trichome, x 400. E- eupatorium riparium Regel,Surface with twin hairs at the rib x 800. F-H. Liatris spicata Willd. F- Cypsela, x 25; Q. Twin hair in surface; H-Subplumose pappus bristles, x 200.

17

Mukheriee & Sarkar

oriented phytomelan plates and discontinuous features or cypsela are very much stable and

deposition of phytomelanin in cS and inner diacritical and are of much value in ascertaining

mesocarpic fiber zone being biseriate. On the other distinct groups or subtribes or even specific limits

hand the genus Mikania (Mikania group) more oI within the lttbe Eupatorieae' Therefore' these

less resembl es Eupatoriunr (Eupatorinae). ' f'eatures of cypselas can be used for imploving

It is clear from these studies that some classification and recognition of taxa together with

external nricromorphological and unuio*ilti conventional othel features'

KEY TO THE SPECIES

A. Cypselas pentangslar usually with 5, ralely 6 ribs; pappus bristles uniseliate, tltin, scabtous to capillaceous: innet'

rnesocurprc zone unrseriate; cypseltr wall possess ilur.rout botdered pit-like phytomelan tings; cypsela always less

than L0 rnm wide.

B Cypselas pentangular.with inconspicuous [ibs; outer mesocarpic zone vety.wide composed clf 3-5 rows of lalge

par.enchymatic cells ani inncr phytometon tny.i-ttrio multiiayered, cellular "Mikania linen'rs

BB. Cypselas pentangular with very conspicuous ribs, ourer mesocatpic zone very nal'row, cornposed of phytonelan layer'- -

ol6i.'g witti uniser."iate parenchymatoui cells; testa unilayered, cellular or collapsed layers.

c. car.popodiurn poorly developed: cypselas tluncate at apex: pubescent glandular; pappus bristles united at basc in a very

nan'ow llng.

D. Carpopodium diameter mol.e o[ less same as the base of the cypsela; thick-walletl cells absent in calpopodiutn; cl'oss

section of cypselas pentangular'.

E Cypsehs 2.5-3.5 mm x 0.6-0.g rnm: glands sessile to short pedicellate; tip of the latelil] cells of bristles mot'e ot'less

EE.Cypselas t.5-2.0mmx0.4-0.5mm;glandulaltrailswittrlongbisedatepedicel;tipofthelateralcellsof thebristles

DD. CaLpoporlium diameter. sliglrtly wider than the base of the body; uniseliate, thick-walled cells found in i;arpopodium;

cr.oss section of cypselas usually pentangular, tafOo* hexanguiar; """""Etr1tcttot'iuntchinente vat" foTolen'\e

CC. Calp0podium well developed; cypselas not tl'uncate at apex; pubescent nonglilndtrlar: pappus bristles united at base in

a vely wide ring.

F. Clr.popodiunr diameter more ol'less salne as the base of the cypsela; pubescence two types' "Twrn type" with unequal

body cells on.t unt ronJe6 ririi"ir r'ulticellularlioiil pt.t.n.. of i-3 colourless lalge cells at the tip of each

FF. carpopodiurn widel than the base of the cypsela; pubescence on[y "Twin type" with lrlore ol' less equal body cells;

AA Cypselu mole ot less cylindr.ic with l0 pr.ominent dbs; pappus'bristles,biseriate' thick, subplumose to plulnose. innel

nresocar.pic ,un. uirJ,lili!",il;.il;;;J;;;;;r h;i;;nioiiy oti"nt.o phvtomelan plates; cvpsela alwavs I 0 mm .t'................Liatri s spicu tn

tnore in diarnetet'

ACKNOWLEDGEMENTS

The authors are grateful to the Directors and

Curators of the four Herbaria (BRI,RB,TAI &- Z)

for sending identified mature cypselas and to the

Incharge, R.S.l.C., Bose Institute, Calcutta for

pLoviding SEM facilities.

REFERENCES

BARTHLOTT, W. 1981. Epiderrnal and 'seed surfacc

characters of plants : systematic applicability and

ABBREVIATIONS

VT=Viiscular h'ace'

18

J. Plant Anat. Morph.

some evolutionary aspects. Nora'. l. Bot. l(3) :

345-355.

BLAKE, A.M. 1928. The akenes of some Compositae. MDak. Agr. Coll. Bull. 218: 4-19.

GRA.U, J. 1980. Die testa der Mutisieae und ihresystematische bedeutung. Mitt. Bot. Munchen 16 :

269-332.

HAQUE, M.Z. & M.B.E. CODWARD 1984. Newrecords of the carpopodium in Compositae and itstaxonomic use. Bot lour. Linnean Soc. 89(4) :

321-340.

PANDEY, A.K. 1989. Phytomelanin-Heliantheae,Asteraceae. Proc. 87th Ind. Sci. Cong. (Sect. Bot.).lll:2M.

Vol.7 No. 1, 1997

PANDEY, AiK. & R.P. SINGH, 1979. Development ofseed and fruit in Compositae : Eupatorieae. J. IndianBol Soc,68 (Suppl.): 5.

ROBINSON, H. & R.M. KING, 1977. Eupatorieae-statematic review. In V,H. Heywood et al. (eds.),

The Biology and Chemisul, of the Compositue,\ol.L Academic Press, London.

SAHU, T.R. 1984. Studies on the trichomes of someEupatorium species. J. Econ. Taxon. Bot. 5(5) :

I 175-l 180.

WILCOX, B.H. 1977. A systematic study of thekucanthemutn - Chnsanthemum complex in NorthAfrica. Ph.D. thesis, Universiry of Reading.

19