Dptprmlr'!.tion of the Somatic Chromos')rne Numoar of Polygorlum tel1ue
Ar Honors fhpsis (ID 499)
By
.Janice L. BDby
Dr. The'mas R. Mertens
Ban
3tat,p University
IVjunc-le, Ind i.ana
tv:ay. 1 Q78
3prinp: )uarter,
1(~78
De+>ermi n;:ct ion of +,h'?
~)omat 1c
Chromosome Number of Pol,vgonum I,enue
Int.roduction
Plant taxoJlomists hi'iV8 disagreed for years cor:cerning the sect"ion of
genus Polygonum
has been
~o
whlch
tradit~0nally
f.
tenue should be i'issigned.
Although the species
assigned to genus Pol,vBonum, section Avicularia
(Polyp;onum). sev,?ral resei'irchers have proposed thi'it
TTlember of genus .?olygonum, seetlon Duravia.
fi'ict that several tra} ts of
.E.
E.
tenue is actua1ly a
This pronos;1J
is haSf'd on the
tenUf-? are contradictory to t.hose characteristiC'
of section Avicularia as a whole.
Hedberg (6) established t.he ] 1 mlts of perms Polygonum. sect ion Avicularia
on the b:-'lsis of
snecies from
-:-:0]] 8T'
sec-~ion
mornrnlor;y.
Th):::-, rd j mi!'1i'i ted most North Ameri C'2.n
Avicularia. and pJaced them in section Duravia.
Biosystematic studies donp in thr- 19606 clarified the positions of ,;everal
of those North American snecies
assi~ned
to section Avicularia.
Styles
(13) nerformed a detailed biosystematir study of section Avicularia in the
British Isles wh'ch resulted in estat'lishin,rr SPAdes limits based on floHer
and achene characteristics.
habit, leaf
char~cteristics.
He-dens (q) founel
.E.
StyLes al.Sr. corrplated these trajts with p1a!lt
habitat, ard
rhromoso~p
number.
Raven anrl
ienUI? tel bl? morrJholoP:2cal1y s;mila.r:' t.o four ot.her
memhers of sectinn AVl r 'ularia with reEpect to fruit and pe"ianth rharactpristics,
but fouml the D011,::;n to be of thf' tyne found in plant.s of section Duravia.
1
2
An investi,a:at-,irln by Savarp arrl Mprt(~ns (11), usinf, StvlRs' method""
of other
wp~ber?
of section
study, aJ~,n f 01.: nrl
of
~r=40
.E.
teJ'lW" fe' be lacki"'fY th's ba'lo.
or 2n=60.
they were more
rolygonu~.
~~ture.
revP21ed
order to
5
m~
('0)(1
lonv.
shc'cl{ P1
The
I'("Ie
D
probrvos.
:ips Hero then placed in a 0.002 mol'l: Gollltio)'l 0+'
",x,vqllinol ire for three hO'Jrs tc CCi 1lse thl"' ~f'rC"10S0me~, t,n ('0ntr'l('t.
li1:nn 'Jnt'l
it
Ttl'
rr; i 1 Prj •
Th?
1 :-'.st
1
PH'1
4
(In'? cell was
color film ;81-83.
nh()togT~phod
lJsin,o; i<
Tnp cell
und,?r +he 1 lOx
W;LS
Koc!a~;
15
b:,-ck and Kodak photorricrogra:>hv
TYJ'1
0 i
1
o".i{~cti
factor of 1.2, givl'1f" a t.otal- magnific"ltion of 1200x.
'So spconrls Hith the 11sht at maximll;>l
i'1-i- py]sity
ve. wi I h
~l
zoom
EXIJ('Sllre timp
wl.S
and uS1ng nhilse cantril,,+; oDt1cs.
113t'1 and Discussion
Def1 n; te chrnf!1osome counts wen? obt:l i :'8ri :'or Polyv,onum terpJe fron
two seeds:
p. t.'?r:'Je t Rocheste-C'. Ful Lm Co •• Ind
SomC3..~,i;::-ef)',H:t of'Vl· (Figure 1).
ian~,
(lctnr.)f?r 2, 1 077.
p. ~!let Ro~host.'?r, FuJt'm Co., Ind.iana, Oct.ober 2,1 077.
Somatic:: cf)unt of Jh (Fir;ures ?,~).
the chromnsol'1Ps,,"C', thev ,'1,;:me:tr8d in +J'1J' eel.ls.
Mold ofte'1 g-r8W In tho soeds, m'1kin.n: those root til'S unusahle; "1any seeds
simply did :.ot E:,')rn:irl.t.e 3.t.
many root
thus
t~ns
ma~in7
~t
w?re not.
ClJl;
:1.':rl
~row~n~ f~st
difficult to find
Of'
those' seeds trnt d i c1 ,a:erminat.e,
pnou~h
~811s
w!~h
~0
hqve many cells
chromosoMes.
rtividi~g,
Many of the cells
wi,t,h chromosomes vis i b1e rlir1 no:' have the n '1clF?ilY' membra.neG
ruc'turf~:l,
so
tha+, th0 chromosomes wen; not sDn'ad aTl;j rt suffici ently, or else the chr:Jm0somes
were not flattened enough, ;:t1so
Several
it in section
~evR
rnak~nrr
~t
impossin1e to mak..; an ac(;u,..ate count.
have been constructed for
Av~clJla.:ia.
E.
tenue, all of whleh
~nclude
o·p t.hese keys, the rno'3t recent is one hy Savilp'e
and Mertens (11), whkh uses ;i.shenp cha ncteri~3tics to position the rii fferent
snec~",s
of s,-'cti:m
the k8.v for sect ion
.-
AVlclll~iri.a.
Avi.cl~+ari.a
Savage a:'d Merterls il'Jcluded
E.
tel'Jue 1:1
for conveni enee, ::.1.1 tho'.w;h they fel t +.h'{ +
P. tmllle be1::m9:ec' in ser!tion Duravi.a.
Their
k(~yis ;l~~
follows:
Achene surfE.ce nrrc;dnmi nantl.v smoot h 3.ni shin.v but may havp ~'it 1, DDled
or ~,;tr; ;lted edGes; i :lflo~escences a :lpeilC to he terl1j r!a1, thf' flow':'s
heiClt'; moy'p-(lr-les c c1ustr:rerl at. tlJe <?'"'ris of 2,tr;'~::, :l1'or'grp,1: 1c ed leaves
,
•
..
• I, • • ••
.'
~
,
•,
, , ,• •
•• ,
f ,
~
F'ip;ure 1.
Dia,o;r:rrmaLir: 1 i 'Ie draw:tDp: of cell of Pol onum tenue.
number 2.Q.'-14 (1200x l1HfTnification •
,
Chromosome
,
, ...-- •
, •, ,..
•
.,.•,, •,
,,
•
,
• •
•
f
",
•• •
Fi p:ure 2.
riP dr!~wi ng of cell of Pol v onum tenue.
number 2n=:~4 (120()x mar;nification •
Diavramrrat"ic 1 i
L:hromosorne
Fir::ure '3.
PhotolYraph of chr
l-'i,a:u re 2.
lmOSC''i1(':3
of reI] of J:olyp:onum t',nu.£. as shown
ChroIr.O",ome nu mber 2Q=1 L} (120Cx map"n i fi eel, t
-i
on) •
in
7
or bracts; D~~rianth t i Pc'rt.J y o;Yc'ressed to the achf,me, wh j ch hCls threE'
equal concave s ii es.
E:tsh f~l~'" of bl2.ck, tri,o;or'ous CJ.~hene is smooth ard. shiny but
bordered with st_rlCited or stippled ;na.rgin; plant slenner, stiff'
or wir v : leaves lirear ,
SavaD'p and ~1erte'ls (11) also desr~ribed the habitat of t-.h"" filant, <~indirlf"
i t s'lndv
ilY!c1
hil-v (Flf'llreS 4,5).
Kevs by other
alJ i
,hors, how"Jr-r,
The key 'oy CorreH and ,Johnst.on (2)
1188
different. chara.cteristics.
ohse-y'vl[lO" Lh1.t this snecies prefers slirrht1y acjcl soil, and
exnosed areas wh·'~re few
0;'
n(' other n1·'3.rts
1X'"
i~3
r:r'owing (Figures
Deam (3)
found in
L", til.
Fernald (h) uses the S;lTre stc'm and hr'lnrh t.rQ. its as dops Deam, but ~tls0
does: hOWf';ver,
p(~diceJ
trait" and thE" serr2.t1or of leaves arp 2.1sn 'lsed by
traj t,s to senara - e P. ten)1f' f'rorn C.hr: ()thor species in sect.ion Aviculariq:
axillar.v r;l'Jsters; stem hrancherl. mainly from
achenes ova 1d.
haSei br;lnches erect or
','he general rnnrnhologi ca 1 dpSl",l nt i
authors do not vary greatly.
rl n.
the
Unfnrtu~ately,
0YlS
of ,E.
none of the
tem~~
b:J ;c:11
desc~i~tions
O~
ljowever. llSP cl-tromos0me rurnbp:s in thel r desr:ri pt ions of Pol,v(,;omlm 5'0",
Whi ch 'lre found ',n Eurone am' assi
rr l'0d
to section Avicularia.
This. howevny,.
8
- - - - - - - - - - - - - - - -----------
Fi p:ure L}.
Fhot,cl",;ranh of FolJgonum tenue.
9
Fir;ure '5.
Fhoto,,,;ranh ot Pol,"flODUl1 ~pnuf.'. 3'" found ::It sit,,, of
near Rochester, Fulton Co"
Indiana.
col1(,ct~on
10
AmRric~.
is found only in North
Differ~nces
Avjc'-ll?ri_~
between sections
and Dur'2-yia are descr1 bed
t,h;:lt sect50Y's ----_.
Duravia and
mosLly by Hpdhprg and Small.
there were f,ome specie"', i r
~",~ti ('1",
.!b ::;a.',!1;'\.
1
whose pol1<?r gra ins were vc.-ry
2) the furrow length ~n :'ect:on Dur.'1.via was shorter thar that of' ~"'c+.io!l
the polar axis, while furrows in
]"(i1]
Pll
11" J 1 en
war f01Jnci onl y
w;:J.S founri
Sm~ll
~
n
~o11er
; n nla'l+s f'rorn the
nlant:~
fr0TT1
TT10si
in
Avicularia were from
sect;0~
N(~w
WorJr'
,
whil~
:;:::"l~ti("n
P.vicu~,Ctria
--_.
__._.
rarts of the wer] d.
(12) descrlh<?d thp mornholo~v of n]ants ;:J.ssigned to sections
Aviculari'l Clnd Dllravia.
He founrl +.h" ;'12.nts in th0
tW)
~',ed,jons
to be veY'y
were 1) in sec:tion Du-"';J,V;2, the leaves were not. articul'lted to thr> ocre"'~.
ser.tjon Duravia
-
;Fl..S
f'~Vf'-Di:lrlpd,
hut could be
fiv0-
or six-TBri.ed in
sf'ct~on
11
of all the s-pec:ies i.n question -pe"rnit assip;nrnpnt of these Sp P c1PS to section
Duravia as he dF:scribed the c;ecUon (12).
The more recent keys and dpscri.rt:inns
mel"'t,ioned above ':11so permi.t assip;nment of P. tenue to section Duravia.
There is st,j 11 need for work nn the taxonomy of
~enus
Pol;vgonum.
An attAmnt should be made to r;ather ('hromator:raphic data allri rhro:1:oso1"1e
nu~bers ~or as
m':lny of the snecies currently asslGnF:d to sectlcns Avicul~ria
and Duravia as nossL ble, in order to
determ~ne
wO'lld ,g]so hAlr to
~p!,(>rrn
i
rH~
which sPPcl es hel em!:', to
whether t.h"'rp is a need La subdivide +hA c:ef'llS
at all.
Conclusions
1) The somatic chromosone nUMber of P. tenup is ?n=l4.
'
2) The chrn:nosome number. pollen morpholop;,v. chromatop;raDhic delta,
to section DUraVl':1 of rr,enlls PO]YfWnum.
3) Further lnvesti.o:atiorl
(E.
cioup"J.asji.
4) The wri
I"
ClS
chromaiop;ranhic
!latsori, etc.1 shou1d be done in cH' effort to clilrify the
ter
r(,co[)1mend~, t hct t
section AvicuJaria a,no
Duravia type
of rhr()mo~cme nunbe:rs"nd
t.h;d:~!
s",ct l on Dura via should 1'(>
r:le~;('rir'tjon
cescribecl by Hedberg.
SPDc'lrR
Led from
of t.he f'nrner secLion be marie on
12
Literature Cited
t.
Brnoks.
Geor~e
R. and Thomas R.
st.')OV ,f' FolvF,onum
Irdian.~. Acad~. Sci.
Mer~p~s.
1972.
A
hi0systpm~t10
ramos'Lssimum al!d PolYP'onum tf'nup.
81: 27'7-?8'1.
Frac.
2.
Correll. DO'1ovaY' S. and Marshal] C. Joh:ston. lQ70.
iViarlual s;f. th.r.;.
Vascu};lr Plant-,s of Texas. Texas Hesoarch F'oundat1on. Rem·Qr.
'3.
Deam.
4.
~'prrlald,
5.
Glf?asor, H. A. 1052. ;~ew Britton ano Brr·wn Jllustrat.eri E'10r:. !)f 1l'.t.
Northeast.ern Urd ted St.;jt.es ii.nd_ fanar-!?, Vol 2. New Ynr'k"lota,Yllca]
Garopn, New York.
6.
Herlb::rr, Ol:w. 19h6. "pollen morDholopy in the. fSenw; PoJyP;onum L. s.
lat.. a'1d its t.axnrlomica 1 ,;jrrr.iri 0arce. Svensk. Boian. Tidskr.
Ch~J..:rJ=·s C.
191..1-0. Flora cf Indiana.
Conservation. 1nrJianapol is.
['1. L. 19<:;0.
C"., N?w York.
Indiana De--P3xt.r!pnt of
Crav's Manll§-l of Botany, Ed. 8.
Ampr-jran B00K
1+0: 37t-404.
7.
Jones. funi·:;-l M. and Thomas n. Mertens. 1971. A taxo:lomic sT.udy of
genus .Polygonum employinlf chromato.<:jraphic methods. Proc. lDQiana
Acad. :;3cL 80: 422-1+30.
B.
L~ve, A. anri
9.
MerteN;. ThOr:las R. (3 r'rl Peter H. Raven. 1965. Taxonomy of PoJ. vgonum.
sectio, PoJygo[1um (Avi'C'llaria~1 in North Amprjca. Ma.dro-n(~ 18:
D. L8ve. 1956. Chromosomes and taxonomy of eastern
North American Pol,v&.onum. Can • .T. Bot. 111.: 501-521.
35-92.
,
H. Mertens, 2nd Joyce ~. Highwood. 1970.
Cytotaxonomic note~ on ,-~pr'\Js Pol,v~onum, section PoJ,vp;onum.
Free. Inoiana Acad. Sc i. 79 : ~i96-400.
---,----------
10.
!V;oore, Donald
11.
SavagG, Argyle D. a.wl Thomas R. Mertr",s. 1968. A t.c~xonomic ~3t,ud'.' of
p;pnus ?olYBonum, s0ction Polygonum (Avicularia) in Tndiana and
WiSCOr!3in. ?roc. ndiana Acad. ~cj. '77: 357-369.
12.
Small, J. K. 189'5. A Jl-lanop;ranh 0[' the North Amf'rlcan Species of the
Genus !olygonum. Memoirs frrm t.he Depa.rtment of Botany of Columbia
ColleG'~' Vol 1.
13.
3tyles. B. T. 1062. The taxonomy of Pol,vp;onwr. aviculare 3.nd -its '"-lJ~es
in Br~,ain. Watsonia 5: 177-2F+-.
14.
Tutin, T. G."
\'
1 ~.
et a1.. cds. 19ffi.
Press, Ca.mbridge.
UnivAr~;:ity
?'lora tl,uropa,('a. Vo1. 1.
Cambridge