Angiosperm genome comparisons reveal early polyploidy in ...
Chromosome Studies and Polyploidy Analysis in Grasses of West Pakistan I
Transcript of Chromosome Studies and Polyploidy Analysis in Grasses of West Pakistan I
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Caryologia: InternationalJournal of Cytology,Cytosystematics andCytogeneticsPublication details, including instructions for authorsand subscription information:http://www.tandfonline.com/loi/tcar20
Chromosome Studies andPolyploidy Analysis in Grassesof West Pakistan IS. R. Baquara & Manzoor Saeeda
a Cytogenetics Section, Central Laboratories,P.C.S.I.R., Karachi-32, PakistanPublished online: 29 Jan 2014.
To cite this article: S. R. Baquar & Manzoor Saeed (1969) Chromosome Studiesand Polyploidy Analysis in Grasses of West Pakistan I, Caryologia: InternationalJournal of Cytology, Cytosystematics and Cytogenetics, 22:2, 103-111, DOI:10.1080/00087114.1969.10796328
To link to this article: http://dx.doi.org/10.1080/00087114.1969.10796328
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CARYOLOGIA VoLUME 22 APRILE-GIUGNO 1969 NuMERO 2
CHROMOSOME STUDIES AND POLYPLOIDY ANALYSIS IN GRASSES OF WEST PAKISTAN I
S. R. BAQUAR and MANZOOR SAEED
Cytogenetics Section, Central Laboratories, P.C.S.I.R., Karachi- 32, Pakistan
Received: Gtli July 1968
INTRODUCTION
In view of the economic importance and the scarcity of cytological information on the family Graminae in Pakistan, a chromosome survey and polyploidy analysis has been undertaken. Barring a few stray records, practically no work has been done so far on the cytology of grasses in Pakistan. The only record worth mentioning is that of SAKAMOTO and MuRAMATsu (1965) who studied 36 species from Pakistan, Afghanistan and Iran, during the Kyoto University Scientific Expedition to Karakorum and Hindukush in 1955, which includes not more than seven species from West Pakistan. The present work comprises chromosome counts of 20 indigenous species (Table I) four of which are reported for the first time (Chrysopogon aucheri (Boiss.) Stapf; Aeluropus lagopoides (L.) Trin; Sporobolus marginatus Hochst; Urochondra setulosa (Trin.) Hubb.). The last mentioned species represents a genus not studied before. In 8 of the other species our numbers are different from numbers earlier reported ( Brachiaria ramosa ( L.) Stapf; Echinochloa colonum (L.) Link; Setaria tomentosa (Roxb.) Kunth; Cymbopogon jawarancusa (Jones) Schult.; Lasiurus hirsutus (Forsk.) Boiss.; Dactyloctenium aegyptium (L.) Beauv.; Eragrostis pilosa (L.) Beauv.; Chloris barbata Sw.). In the remaining 8 species, our counts corroborate earlier findings.
MATERIALS AND METHODS
In 8 species gametic chromosome counts were made from the pollen mother cells (PMC's) for which buds, collected from the plants growing in their natural habitat, were fixed in Carnoy solution (ethanol-chloroform-acetic acid in a ratio
[Caryologia, Vol. 22, n. 2, 1969
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TAB
LE
I
Show
ing
the
chro
mos
ome
num
bers
, lo
cali
ty
and
date
o
f co
llec
tion
of
pl
ants
in
vest
igat
ed.
Tri
be
-S
peci
es
PA
NIC
EA
E
Bra
chia
ria
ram
osa
(L.)
S
tapf
Cen
chru
s pe
nnis
etif
orm
is H
och
st.
C. s
etig
erus
Vah
l
Ech
inoc
hloa
co
lonu
m
(L.)
L
ink
Pan
icum
an
tido
tale
R
etz.
Loc
alit
y an
d
dat
e o
f co
llec
tion
Kar
achi
, C
entr
al
Lab
s.,
Cam
pus,
24
-4-6
7
Kar
achi
, C
entr
al
Lab
s.,
Cam
pus,
5-
4-67
Kar
achi
, N
azim
abad
, 18
-4-6
7
Kar
achi
, E
xh
ibit
ion
g
rou
nd
, 17
-4-6
7
Kar
achi
, M
alir
, 29
-4-6
7
c :ll ... 0::
n 12*
-- - 9''
9
Pas
pali
dium
gem
inat
um (
For
ssk.
) S
tapf
In
du
s D
elta
, m
oist
fie
lds,
9
Mir
pu
r S
akro
,
Pas
palu
m
scro
bicu
latu
m L
.
Seta
ria
tom
ento
sa (
Rox
b.)
Ku
nth
* N
ew
reco
rds.
21-2
-68
Ind
us
Del
ta,
wat
er l
ogge
d ar
eas,
Mir
pu
r S
akro
, 21
-2-6
8
Kar
achi
, D
um
loti
, 22
-5-6
7 9*
c .!2
~ =
-~
. !2
>
... ~
>
p..
c ......
2n
n 16
17
34
-18
34
27 9 20
40
18
c .g .. -~ ...
Au
tho
rity
>
c ...... 2n
PAT
IL a
nd
GH
OSH
196
2 36
M
uLA
Y
and
LEE
LAM
MA
19
56
AB
BA
SI a
nd
IsL
AM
196
8 34
A
BB
ASI
an
d I
SLA
M 1
968
DE
LIS
LE
19
63
34
}AN
AK
I-AM
MA
L (i
n D
AR
LIN
GTO
N a
nd
WY
LIE
195
5)
36
FISH
ER
et
al.
1954
CH
EN a
nd
Hsu
196
1; Y
AB
UN
O 1
962;
GuP
TA
196
3 36
B
RO
WN
19
50;
NU
NEZ
19
52;
CHA
ND
OLA
19
59
48
K
RIS
HN
ASW
AM
Y a
nd
R.
1949
54
D
E W
ET
195
4; S
ING
H a
nd
GoD
WA
RD
19
60;
PRIT
-CH
ARD
an
d G
oUL
D
1964
; TA
TEO
KA
19
65
72
}AN
AK
I-AM
MA
L (i
n D
AR
LIN
GTO
N a
nd
WY
LIE
195
5)
18
BuR
TON
19
42
RA
MM
AN
et
al.
1959
18
TA
TEO
KA
19
65
CH
EN a
nd
Hsu
196
1; G
uPT
A
1963
40
A
vDU
LOV
19
28;
LAR
SEN
19
63
GuP
TA
19
63
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TAB
LE
I
Show
ing
the
chro
mos
ome
num
bers
, lo
calit
y an
d da
te
of
colle
ctio
11
of
plan
ts
inve
stig
ated
.
Tri
be -
Spe
cies
AN
DR
OP
OG
ON
EA
E
Chr
ysop
ogon
auc
heri
(B
oiss
.) S
tapf
Loc
alit
y an
d da
te
of
coll
ecti
on
Kar
achi
, C
entr
al
Lab
s.,
Cam
pus,
11
-4-6
7
Cym
bopo
gon
;war
ancu
sa (
Jone
s) S
chul
t. K
arac
hi,
Cen
tral
L
abs.
, C
ampu
s,
15-4
-67
Dic
hant
hium
ann
ulat
um (
For
ssk.
) S
tapf
K3r
achi
, N
azim
abad
, 5-
4-67
Las
iuru
s hi
rsut
us (
For
ssk.
) B
oiss
.
AE
LUR
OP
OD
EA
E
Ael
urop
us l
agop
oide
s (L
.) T
rin.
Kar
achi
, U
nive
rsit
y C
ampu
s,
17-1
-67
Kar
achi
, D
umlo
ti,
17-4
-67
1:: 1A " ... Po.
11
LO*
10 9*
c:: .g "' -~ " > c:: >-
< 2n
40*
40
50*
~ 0 ·;; " ... Po. 11
10
10
20
30
28
c:: .g "' -~
Aut
hori
ty
... > c:: >-
< 2n
MEH
RA
et
al.
1962
20
RA
GHAV
AN a
nd A
RORA
195
8; G
uPT
A 1
965
CELA
RIER
et
al.
1958
; M
EHRA
et
al.
1962
C
ELA
RIE
R e
t al
. 19
58;
MEH
RA
et
al.
1962
C
ELA
RIE
R e
t al
. 19
58
20
CEL
AR
IER
and
H.
1957
; C
ELA
RIE
R a
nd M
. 19
59;
SHA
RMA
an
d J.
19
59;
BoRG
AO
NK
ER
and
DE
W
ET
1960
; D
E W
ET
, M
EHRA
and
BoR
GA
ON
KER
19
61;
BoRG
AO
NK
ER a
nd S
. 19
62;
DE
WET
et
al.
1963
; H
ARL
AN
et
al.
1964
; R
oY
et a
l. 19
65
30
DE
WE
T,
MEH
RA a
nd B
oRG
AO
NK
ER 1
961
40
CEL
AR
IER
an
d H
. 19
57;
HA
RLA
N
et
al.
1958
; Bo
RGA
ON
KER
an
d D
E
WE
T
1960
; D
E
WE
T,
MEH
RA
and
BoRG
AO
NK
ER
1961
; Bo
RGA
ON
KER
an
d S.
19
62;
BoRG
AO
NK
ER a
nd D
E W
ET
196
3;
DE
W
ET
and
RICH
ARD
SON
19
63;
DE
W
ET
et
111.
1963
; Bo
RGA
ON
KER
an
d D
E
WE
T
1964
; H
ARL
AN
et
al.
1964
60
CE
LARI
ER
and
HA
RLA
N
1957
; D
E
WE
T,
MEH
RA
and
BoRG
AO
NK
ER
1961
; M
EHRA
19
61
CELA
RIER
19
57
56
CEL
AR
IER
19
57
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TAB
LE
I
Show
ing
he
chro
mos
ome
num
bers
, lo
calit
y an
d da
te
of
colle
ctio
n of
pl
ants
in
vest
igat
ed.
Tri
be
-S
peci
es
Loc
alit
y an
d
dat
e o
f co
llec
tion
ER
AG
RO
ST
EA
E
Dac
tylo
cten
ium
aeg
ypti
um (
L.)
Bea
uv.
Kar
achi
, D
um
loti
, 12
-8-6
7
Ele
usin
e in
dica
(L
.) G
aert
n.
Era
gros
tis p
ilosa
(L
.) B
eauv
.
E.
tene
lla
(L.)
Bea
uv.
CH
LO
RID
EA
E
Chl
oris
bar
bata
Sw
.
SPO
RO
BO
LE
AE
Spor
obol
us m
argi
natu
s H
och
st.
Uro
chon
dra
setu
losa
(T
rin.
) H
ub
b.
Kar
achi
, D
um
loti
, 12
-8-6
7
Kar
achi
, C
entr
al
Lab
s.,
Cam
pu
s,
27-4
-67
Kar
achi
, U
nive
rsit
y C
amp
us,
17
-4-6
7
Kar
achi
, N
azim
abad
, 27
-3-6
7
Kar
achi
, M
alir
, 29
-4-6
7
Kar
achi
, D
um
loti
, 22
-5-6
7
Ind
us
Del
ta,
Gh
aro
, 31
-8-6
8
c::
c; .g ..
:ll -~
... ... p..
GJ >
c:: >-<
n 2n
9*
18
10*
10
Ca5
0*
9*
20*
14*
c:: ;;
.g -~
.. -~
GJ
~
Au
tori
ty
... p..
>
c:: >-<
n 2n
10
-G
oUL
D
1960
20
TH
OM
AS
(in
DA
RLI
NG
TON
an
d W
YL
IE
1955
) 36
S
ee
LoV
E
and
Lo
vE
19
61
40
TA
TEO
KA
19
65
48
AV
DU
LOV
19
31;
}AN
AK
I-A
MM
AL
(in
D
AR
LIN
GTO
N
and
WY
LIE
19
55);
LA
RSE
N
1963
9 -
Gou
LD
19
60;
CH
EN a
nd
Hsu
196
2;
SIN
GH
19
65
18
-Su
BR
AM
AN
YA
M
and
K
AM
BLE
19
67
-18
S
ee L
ov
E a
nd
Lo
vE
196
1 36
M
OFF
ET
an
d H
. 19
49;
LAR
SEN
196
3; M
EHR
A 1
963
40
0H
NO
an
d T
ATE
OK
A
1953
; TA
TEO
KA
19
55
60
BoW
DEN
an
d S
ENN
196
2; T
ATE
OK
A 1
965
10
-C
HEN
an
d H
su
1962
20
LA
RSE
N
1963
; TA
TEO
KA
19
65
20
-
CH
EN
and
Hsu
196
2 20
A
VD
ULO
V
1928
4
0
}AN
AK
I-AM
MA
L (i
n D
AR
LIN
GTO
N a
nd
WY
LIE
195
5)
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CHROMOSOME STUDIES IN GRASSES 107
of 6:3:1) for 24 hours, stored in 75% alcohol and later squashed in acetocarmine. In 10 species somatic counts were made in root cells which were obtained from the transplanted plants. In a few cases roots were taken from the seeds grown on moist filter paper in petri dishes at room temperature (25-28 °C). After the usual process of dehydration and paraffin embedding, blocks were prepared and 10 1..1.
thick sections were cut by microtome. Iron haematoxylin was used as the stain. In 2 species counts were made in both root cells as well as PMCs.
Camera lucida drawings were made at a magnification of approx. 2000 X in all the species. Plants were identified after BaR (1960) and }AFRI (1966). Voucher specimens are deposited in the Central Laboratories Herbarium (CLH), P.C.S.I.R. Karachi.
RESULTS AND DISCUSSION
The occurrence of polyploidy is quite indicative from the previous literature supported by the results of the present investigation as provided in the Table I. It will be evident that no less than 9 species, including our observations, show signs of polyploidy, 3 of them are based on basic number 9 (Echinochloa colonum, Setaria tomentosa, Eleusine indica), 4 on the basic number 10 (Cymbopogon jawarancusa, Dichanthium annulatum, Eragrostis pilosa, Chloris barbata), 1 on the basic number 12 (Brachiaria ramosa), and 1 finally with polyploidy on both the numbers 9 and 10 (Dactyloctenium aegyptium). In Cymbopogon jawarancusa, the chromosome numbers indicate the presence of two chromosome races, a diploid and a tetraploid race, on the same basic number (n=10, 2n=40). In Sporobolus marginatus also the presence of two races, on diploid level, was recorded but with different basic numbers (n=9, 2n=20).
TABLE II
Chromosome numbers counted Number of forms
n 2n (species, races)
14 1 9 18 8
10 20 5 12 1
34 2 40 3
50 (c 50) 2
Including the chromosome races mentioned above the chromosome numbers found in the present investigation may be summarized as given in the Table II. It is very suggestive that in six of the species, the gametic
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108 BAQUAR and MANZOOR SAEED
Figs. 1-22. - Showing gametic and somatic chromosome numbers of the plants investigated.
Fig. 1. - Brachiaria ramosa n = 12 (Met. I) ,. 2. - Cenchrus pennisetiformis 2n = 34 (Met. ) ,. 3. - Cenchrus setigerus 2n = 34 (Met. ) ,. 4. - Echinochloa colonum n= 9 (Met. I) ,. 5. - Panicum antidotale n= 9 (Met. I) ,. 6. - Paspalidium geminatum n= 9 (Met. I) ,. 7. - Paspalum scrobiculatttm 2n = 40 (Met. ) » 8. - Setaria tomentosa n= 9 (Met. I) ,. 9. - Chrysopogon aucheri n = 10 (Met. I) ,. 10. - Cymbopogon iwarancusa n = 10 (Met. I) ,. 11. - Cymbopogon ;warancusa 2n = 40 (Met. ) » 12. - Dichantium annulatum 2n = 40 (Met. ) » 13. - Lasirius hirsutus n= 9 (Met. I) ,. 14. - Aeluropus lagopoides 2n =50 (Met. ) ,. 15. - Dactyloctenium aegyptium n= 9 (Met. I) » 16. - Eleusine indica 2n = 18 (Met. ) ,. 17. - Eragrostis pilosa n = 10 (Met. I) ,. 18. - Eragrostis tenella n = 10 (Met. I) ,. 19. - Chloris barbata 2n = Ca50 (Met. ) » 20. - Sporobolous marginatus n= 9 (Met. I) ,. 21. - Sporobolos marginatus 2n = 20 (Met. ) » 22. - Urochondra setulosa 2n = 14 (Met. )
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CHROMOSOME STUDIES IN GRASSES 109
I t~\'11.- -,. .. tl ~ ,~,··( ''!'!Jt.• • •• •••• ., ••• _,_, :·· • ••• c ~ ~ ,, ., ... , . ••• ... ~~~ ,, •
1 ''!. s. 2 --· \ 4 5 -=-- 3 ,, , .. ~•,.., ••• _,. ~ ''~v ,,, _, -.... ~, .. '= •••• ,-·,.'~~ '-' •• ... ,_ ... '~ ..... 8 •'#:'' \ '' ~ ,~ ,, ,,~ ••• :•. - ' ••• ' .~,' ..,
Is \ _ ..... ~ '7 .,9 -r.-=-· ~' •' ·1o 11
"' •••• .,..,. .. ,, ... ,~ •• ,~ ,,..,, ,J, •• '- J,J)' .... I ,.....,.. .... .J ,, •
'--'~}I\ 13 J ,t' (; ,,., ~\7"'1 ~ 1!~ "~ - .,, ~'~""J, .::· ;; ·~~J., , .... ~· '''"" -~ .J, 12 • 15 I I " ' ' 16 ) - s 1,14
-,,,,
, ~' •••• ~'~-..... , ' ,, ,f,u.• .. 17 ::;\ ,,_ ••• 1-;
I ltl' '~ ••• ~·' ,, _ _,
~. J\; ' ,_ ••• '~~ p,, ·--~··-'
-<Ill ..... 20 '"'21 ,. . ''•,•"' "'19 '22 • 18
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110 BAQUAR and MANZOOR SAEED
number reported here represents the basic number of polyploid series, in whiCh only higher numbers were known earlier (viz. the number 9 in Echinochloa colonum, Setaria tomentosa, Dactyloctenium aegyptium, the number 10 in Eragrostis pilosa and 12 in Brachiaria ramosa; also the number 9 in Lasiurus hirsutus, in which earlier onJly n=28 and 2n=56 were known). Though the material presently investigated is insufficient yet it is worth considering whether this is an indication that the West Pakistan flora contains especially primitive forms.
REFERENCES
(References present in DARLINGTON and WYLIE (1955) and LovE and LovE (1961) hac.re not been included in the list given below) .
.ABBASI Z. and IsLAM A. S., 1968. - Chromosome numbers in two species of Cenchrus. Abst. 20th Pak. Sci. Con£. p. 9.
BoR N. L., 1960. - Grasses of Burma, Ceylon, India and Pakistan. Perg:unon Press, Oxford. BoRGAONKER D. S. and DE WET J. M. J., 1960. - A Cytogenetical study of the hybrid between
Dichanthium annulatum and Dichantium fecundum. Phyton (B.A.), 15: 137-144. -, 1964. - Cytogenetical study of hybrids between Dichanthium annulatum and D. fecundum.
III. Phyton (B. A.), 21: 55-60. BowDEN W. M. and SENN H. A., 1962. -Chromosome numbers in 28 grass genera from South
America. Canad. Jour. Bot., 40: 1115-1124. CHEN C. and Hsu C., 1961. - Cytogenetical study on Taiwan grasses. I. Tribe Paniceae. Bot.
Bull. Acad. Sin. Ser., 2.2: 101-110. DARLINGTON C. D. and WYLIE A. P., 1955. - Chromosome atlas of flowering plants. London. DE LISLE D. G., 1963. - Taxonomy and distribution of the genus Cenchrus. Iowa St. Jour.
Sci., 37: 259-351. DE WET J. M. J., MEHRA K. L. and BoRGAONKER D. S., 1961. - Chromosome association in
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SUMMARY
Chromosome studies in grasses of West Pakistan were initiated with a view to study the role of polyploidy in the evolution of species in this region. The present work comprises the chromosome numbers of 20 indigenous species, out of which counts for the following 12 species are new records or different from the previous findings including the report of Urochondra as a genus: Brachiaria ramosa (L.) Stapf ( n = 12), Echinochloa colonum (L.) Link (n =9), Setaria tomentosa (Roxb.) Kunth (n=9), Chrysopogon aucheri (Boiss.) Stapf (n = 10), Cymbopogon ;warancusa (Jones) Schult. (2n=40), Lasiurus hirsutus (Forssk.) Boiss. (n=9), Aeluropus lagopoides (L.) Trin. (2n=50), Dactyloctenium aegyptium (L.) Beauv. (n=9), Eragrostis pilosa (L.) Beauv. (n=10), Chloris barbata Sw. (2n=Ca50), Sporobolus marginatus Hochst (n=9, 2n=20) and Urochondra setulosa (Trin.) Hubb. (2n= 14).
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