Báo cáo " ảnh hưởng của Stress Naci lên sự ổn định của cấu trúc Genome tế bào lúa Oryza sativa nuôi cấy dài hạn In Vitro " potx

Tgp chi Cdng nghi Sinh hpc 1(1):
235-240,
2009
ANH
HirONG
CUA STRESS
NACI
LEN SlT ON DINH CUA
cAu
TRUC GENOME TE
BAO LUA ORYZA SA
TIVA
NUOI
CAY
DAI
HAN IN VITRO
Nguyen Tbanb Thuy,
D6
Quang Binh
Viin Cdng nghi sinh hoc
:•
TOMTAT
Nudi cay in vitro cac te bao thuc vat la mdt cdng cu hiiu ich cho cac nghien
ciiu
lien quan tdi chuyen hda
sinh hpc tir mdt te bao dan le den cay hoan chinh in vitro. Sit dung cdng nghe in vitro nay, cac nha nghien ciru
khdng chi cd the kiem soat cac chudi phan
iing
sinh hgc ma cdn tao ra nhieu san pham mdi khac vdi nhiing san
pham cua cac vat lieu khdi dau. Tuy nhien, sinh trudng frong cac dieu kien nhan tao in vitro frong thdi gian
dai,

te bao thuc vat khdng franh khdi hien tugng bien di soma.
Miic
do bien di cua cac te bao nudi cay phu
thupc vao nhieu yeu td khac nhau gdm cd kieu gen va frang thai sinh ly cua vat lieu thuc vat khdi diu, cac
diSu
kien nudi cay, thdi gian nudi cay Nghien
ciiu
nay trinh bay cac ket qua hen quan tdi nhiing bien ddi phan ttr
frong genome
ciia
te bao
liia
(Oryza sativa) ma chiing da dugc nudi cay frong mdt thdi gian
dM
frong cac dieu
kien cd sfress mudi
(NaCI)
khac nhau bang ky thuat RADP. So sanh vdi vdi vat heu khoi
diu
khdng
bit
ngudn
tir
nudi cay cac te bao phan lap in vitro, genome cua cac te bao nudi cay frong dieu kien khdng cd sfress
NaCI
mang nhieu bien ddi phan tu han genome cua cac te bao nudi cay lien tuc frong
diSu
kien cd sfress mudi. Mac
dii
cac te bao cua hai dang nudi cay nay chia se mdt sd

sir
bien ddi dac thu gay ra bdi nudi cay in vitro dai han,
cac te bao thich nghi vdi sfress mudi chia se nhieu su tuang ddng chung vdi vat heu khdi dau han la cac te bao
khdng bi sfress. Cac ket qua thu dugc tir nghien
ciiu
hien tai phu hgp vdi cac quan sat trudc day cua chimg tdi
dupc tien hanh d
miic
dp te bao la tinh toan nang cua cac te bao
liia
phan lap dugc dn dinh frong dieu kien nudi
cay cd stress mudi thich hgp tdt han frong dieu kien khdng cd yeu td sfress nay.
Tie
khoa:
Bien di
khde
Met,
nuoi cdy te bdo ddi
hgn,
Oryza
sativa,
stress NaCI
su
on
dinh
cua
genome
MdDAU Cvi \M
Nhihig phat hien ca ban ve su sinh truang khong
giai han cua te bao thuc vat frong nuoi cay in vitro

va tinh toan nang cua chiing da tao ca so cho hang
loat huong nghien
ciiu
nhu: te bao hpc, sinh ly, hoa
sinh te bao, cac qua frinh sinh truang va phat frien
cua te bao, nhan dong ca the, san xuat cac chat
thii
cap,
loai bo benh virus, nghien cuu tuong tac giiia
mo thuc vat va cac loai vi khuan tao u - not san
o
cay
va cac nghien cuu di truyen ve bien di, dot bien soma
frong te bao nuoi cay,
iing
dung kha nang tao cay
dan boi, dong thuan frong chpn giong, dung hap
protoplast tao dong lai soma hay lai te bao chat va
chuyin DNA, (Gautheret, 1985).
Tinh toan nang cua te bao cay
liia
tiong chau A
(O. sativa L.) ciing da dupc nghien
ciiu
va chiing
minh bang ky thuat nuoi cay mo, te bao in vitro. Sau
thi nghiem tao mo seo tit npi nhii cua cay ngo do La
Rue
(1949)
thuc hien thanh cong,

Fujiwara
va Ojima
(1955) da tiSn hanh thi nghiem nuoi cac doan re lua
tach rai. Nam 1956, Amemiya va dong tac gia tien
hanh nuoi ciy phoi non cua loai cay luong thuc quan
frong nay. Tuy nhien, tien bp frong nuoi cay mo te bao
cdc loai cay luong thuc mpt la mam bat dau tir viec bd
sung vao moi truang nuoi cay mpt lupng chat dieu
hoa sinh trudng ngoai sinh (Stieet, 1957). Furuhashi
va Yatazawa (1964) da tao duac mo seo tit dot than,
tiong khi Yatazawa va dong tac gia
(1967)
tao duoc
mo seo tit re cua cay ma tiong moi truang co bo sung
2.4-D. Nam 1968 la nam danh dau su truang thanh
quan frpng cua ky thuat nuoi cay mo te bao doi voi
cay
Ilia.
Nhieu phong thi nghiem da tai tao duac cay
Ilia
hoan chinh tir mo, te bao c6 nguon goc tit viing re
cua hat (Nishi et al,
1968),
tii rl (Kawata,
1968)
va tii
phoi Ilia (Maeda, 1968; Tamura, 1968). Dac biet,
Nuzeki
va Oono (1968) da tai smh duoc cay lua don
bpi tir nuoi cay bao phan, tao

tiSn
de cho kha nang
ling dung mpt
each
huu hieu phuang phap nuoi cay
don bpi frong viec nit ngan thoi gian tao dong thuan
va chpn giong
liia.
Nhung nam tiep theo duoc danh
dau bang cac tien bp frong viec chpn dong te bao va
tai sinh cay
liia
tir nuoi cay te bao frong dung dich
long (Abe et al,
1991;
Binh, Heszky,
1990;
Gobel
et
al, 1985). Nhiing thi nghiem ve nuoi cay te bao fran
cua lua cung da dupc tien hanh tir dau nhung nam
1970 (Ham, 1973; Deka, Sen, 1976). Thanh cong
frong viec tai tao cay lua hoan chinh tii nuoi cay te bao
fran bat dau dat duac tir giiia nhirng nam 1980
(Abdullah et al, 1986; Datta et al, 1992;
Fujamura
et
235
Nguyin Thanh Thuy &
D6

Quang Binh
al, 1985; Jenes, Pauk, 1989). Ben canh do, nhiing
nghien
ciiu
ve anh huang cua cac loai sfress khac
nhau
(NaCI,
t°, ) len su tai tao lai thanh te bao
ciia
tl
bao tian va
jkha
nang phan chia te bao cua chiing ciing
da
duac quan tam (Binh, 1995). Ky thuat nuoi cay mo
te bao in
vitro
da duac ung dung mpt
each
co hieu qua
tiong nghien cim te bao, chpn dong chong chiu cac
loai sfress sinh hpc va cac loai sfress moi truang, tao
cac
giSng liia
mai a Viet Nam (Phan Thi Bay et al,
2001;
Nghiem Nhu Van, 1983; Phong et al, 2001)
ciing nhu a mpt so nuac khac (Heszky et al. 1996;
Lestari, 2006).
Cimg vai thatih cong frong viec dieu khien qua

trinh sinh
trudng
va phat trien cua te bao thuc vat
trong dieu kien nuoi cay in vitro nhan tao, cac nha
nghien cim con phat hien ra cac hien tuang bien di
va dot bien di truyen
6
mirc dp te bao va cay tai sinh
CO
nguon goc nuoi cay mo in vitro (Kabir et al,
2008;
Nishi et al, 1968) ciing nhu
o miic
dp phan tu
DNA (Ngezahayo et al, 2007; Rasheed et al, 2005).
Larkin va
Scowcroft
(1981) da dung thuat ngii bien
di ddng soma cho cac cay tai sinh co nhiing su thay
ddi nhat dinh so vdi nguyen lieu gdc ban dau.
Scowcroft (1985) coi nhiing su thay ddi d
miic
dp
nhiem sac the, hinh thai, sinh hoa hay phan tit la su
bat dn dinh do nudi cay in vitro gay ra.
Nghien
ciiu
nay trinh bay cac ket qua ve anh
hudng cua stiess
NaCI

len su dn dinh cua cau
true
genome te bao lua Oryza sativa nudi cay dai han in
vitro bang ky thuat RADP (Random
AmpUfication
of Polymorphic DNA). Ket qua thu dupc
phii
hop
vdi cac quan sat trudc day cua chung tdi dupc tien
hanh d
miic
dp te bao la tinh toan nang cua cac te
bao
Ilia
phan lap dupc nudi cay tiong dieu kien cd
stiess
NaCI
thich hpp da duy tri su dn dinh cua tinh
tiang nay lau dai han so vdi cac te bao sinh trudng
frong dieu kien nudi cay in vitro tuong ddng nhimg
khdng cd yeu td stiess nay (Binh, 1995; Binh,
Heszky, 1990; Binh
e/a/.,
1990, 1992, 1993).
NGUYEN LIEU VA PHUONG PHAP '
Nguyen lieu
Hai ngudn md
liia
nudi cay in vitro dai han frong
mdi trudng cd va khdng cd sfress mudi

(NaCI)
cd
ngudn gdc tir hat
ciia
mdt gidng
liia
faponica cd
ngudn gdc tii Hungary (Binh, Heszky,
1990).
Hat
liia
dupc bdc vd,
khii
tning, rdi duoc cay chuyin len mdi
trudng MS (Murashige, Skoog,
1962)
cd bd sung 2%
saccharose, 2 mg/l 2.4-D, 0,5 mg/l kinetin va
1
mg/l
thiamine, pH 5,6 - 5,7 va 0,8% agar dl tao md so cap
trudc khi dua vao nudi
cdy
dung dich long. Trong
qua tiinh nudi ciy dai han, 2 nam dau tien te bao
liia
dugc
nudi ciy tiong mdi trudng dung dich ldng
khdng cd sfress mudi
NaCI

(Binh, Heszky, 1990).
Sau nam tiep theo, mdt phan te bao nay dupc cay
chuyen vao mdi trudng dung dich ldng cd bd sung
1,5%
NaCI
va phin cdn lai
vin
tilp tuc duoc duy tii
tren mdi trudng ldng khdng cd stress mudi nhu cii.
Nhumg nam sau cua giai doan nudi cay tiong dieu
kien dung dich long cd va khdng cd sfress mudi nay,
cac cum te bao duoc chuyen len nudi cay fren mdi
trudng thach (0,8% agar) voi ndng dp mudi tuong tu
nhu trong mdi trudng dung dich ldng da dung trudc
do (Binh, 1995). Md dupc cay chuyen sau 4 tuan va
sinh trudng d nhiet dp 27 - 28°C trong dieu kien anh
sang khuech tan yeu, khoang 100
lux/lO
h/ngay. Cay
ddi chiing cd ngudn gdc tir hat cua gidng
liia
ban dau
dupc duy tri d dang cay non in vitro.
Pbuong
pbap
Phan ling RAPD dupc dung tiong nghien
ciiu
bien dpng genome cua te bao lua nudi cay in vitro
dai
han.

Phan
iing
nay dupc tien hanh frong the tich
dung dich hdn hpp la 25
|^1
vdi thanh phan
ciia
phan
ling: 10 mM
Tris-HCl
(pH 8,3), 50 mM
KCl,
1,5
mM
MgClz,
0,01% gelatin, 200
\iM
moi loai dNTP,
0,5 don vi enzyme Taq DNA polymerase (Promega),
0,25
|ag
mdi
oligo
ngau nhien (Bang 1) va 20 ng
DNA tdng sd cua mdi mau. Phan
iing
dupc thuc hien
theo chu trinh nhiet: bien tinh ban dau d 96°C frong
3 phut, lap lai 35 lan chu trinh co ban (bien
tinh

d
96°C/45 giay, gan mdi vao khudn d
42°C/1
phiit, keo
dai d 72°C/2 phiit), keo dai d
72°C/8
phiit d giai
doan cudi cua phan
iing.
San pham cua cac phan
iing
RAPD nay dupc bao quan d
-20°C
de dung cho
nhiing nghien
ciiu
tiep theo.
Bang
1.
Cac doan moi oligonucleotide dung trong phan u'ng
RAPD.
STT Trinh
tiF
base (5' - 3')
gaggcctacgccccatagaa
aatgcgttgaggcgcagcag
cggaagcaatttgcttggct
gcaattactatggctcggca
ctccctcatgattcttggga
ttgttcctgaccctggttca

caattcgaggatccagagac
tgccttgatccacttggcta
236
Tgp
chi Cong nghe Sinh hpc
1(2):
235-240, 2009
^
Cac phan
iing
duac lap lai 3 lin, cac bang hinh
on
dmh
dupc ghi nhan va so lieu duac phan tich
bang phan mem NTSYS-pc 1.80
(Rohtf,
1993).
KET QUA
VATHAO
LUAN
Nhiing bien ddng trong ciu tiiic cua genome tl
bao lua nudi ciy dai han frong cac dilu kien cd va
khdng cd sfress mudi
NaCI
dupc khao sat bing ky
thuat RAPD vdi 8 mdi oligo (Bang 1). San phim cua
phan ling RAPD vdi hai
mlu
tl bao tren duoc so
sanh vdi san phim tuong ddng cua cay ddi chiing.

Kit
qua dien di cac san phim RAPD cho thiy cac
mlu
DNA cd ngudn gdc md, tl bao khac nhau tao ra
cac san phim cd mlu bang da hinh DNA khac nhau
(Hinh 1, 2).
Hinh 1. Bien di (gel agarose 1%) cac san pham RAPD vdi
doan mdi oligo so 3
(1
- 3) va 4 (4 - 6) cua: genome cay ddi
chiing (1, 4), ti bao nudi cly in vitro dai han trong mdi
trudng khdng cd stress mudi NaCI
(2,
5) va cd stress mudi
NaCI (3, 6).
M:
thang DNA chuan
123
bp
(Gibeo).
Trong sd cac bang da hinh, mdt sd bang DNA
chi dac trung cho md cua cay
liia
ddi chiing, hay cac
bang dai dien chung cho cac loai tl bao lua nudi ciy
in vitro ma khdng phu thudc vao dieu kien nudi ciy
co hoac khdng cd stress mudi
NaCI
cua chiing. Mpt
sd bang khac

dac
trung cho cac tl bao nudi ciy trong
mdi trudng khdng cd stress mudi, hay cac bang chi
cd mat trong san pham
ciia
phan
iing
RAPD vdi
DNA cua te bao nudi cay cd stress mudi va mo cua
cSy
ddi chiing, Tdng hop ket qua
ciia
phan
iing
RAPD vdi 8 mdi oligo va ba loai miu md, tl bao thi
nghiem, chiing tdi thu duoc tdng s6 bang DNA la 50,
trong sd do 20 bang la bang da hinh, chiim ty le 40%
(Bang
2),
Tren co sd cdc sd lifu thu duac tii phan
ling RAPD, cay lidn ket phan tii
nhirng "viing
genome
duoc khao sat bang 8 mdi oligo diing trong thi
nghiem nay, ciia ba loai md, te bao khac nhau ndi
tren duoc xay dung theo chuang trinh NTSYS-pc
1.80 (Hinh 3).
1107
Hinh 2. Dien di (gel agarose 1%) cac san pham RAPD vdi
doan mdi oligo sd 2 (1 - 3), 7 (4 - 6) va 8 (7 - 9) cua:

genome cay ddi chiing
(1,
4,
7),
td bao nudi cay in vitro dai
han trong mdi trudng
l<hdng
cd stress mudi NaCi (2,
5,
8)
va cd stress mudi NaCI (3, 6, 9). M: thang DNA chuan 123
bp
(Gibeo).
Bang 2. Ty
l#
bang da hinh dua tren chi thj RAPD cua
genome cd ngudn gdc
tCr
cay ddi chiing, te bao nudi
ciy
in
vitro dai han trong mdi trudng khdng cd stress mudi NaCi,
va cd stress muoi
NaCI.
STT
1
2
3
4
5

6
7
8
Tong
Mdi
1
2
3
4
5
6
7
8
8
Tdng
9
7
8
5
7
5
5
4
50
s6 bang S6 bang da
hinh
7
3
4
2

1
0
2
1
20
Qua hinh cay lien ket dua tren cac chi thi phan tir
RAPD, chiing tdi nhan thay nhung vimg genome
dupe khao sat cua te bao liia nudi cay trong dilu kien
cd stress mudi
NaCI
cd mirc dp tuang ddng vdi
237
Nguyen Thanh Thuy & Dd Quang
Binh
nhiing viing genome tuong
iing
cua md cay ddi
chiing ldn hon nhiing viing genome tuong tu cua te
bao nudi cay frong mdi trudng binh thudng khdng cd
stiess mudi
NaCI.
Ket qua thu dupc frong thi nghiem nay phan anh
nhiing bien ddng frong cau tnic phan tir xay ra tai
nhung
viing nhat dinh frong genome dupc khao sat
cua cac loai te bao
liia
nudi cay dai han in vitro trong
cac dieu kien cd va khdng cd stiess
NaCI

la khac
nhau. -Genome cua quan the cac te bao sinh trudng
frong dieu kien cd stress mudi
NaCI
cd
miic
dp dn
dinh cao hon so vdi genome cua quan the cac te bao
sinh trudng frong mdi trudng co ban khdng cd stiess
mudi
NaCI.
Kit
qua nay phu hpp vdi nhung ket qua
da dupc cdng bd trudc day cua chimg tdi (Binh,
1995;
Binh, Heszky, 1990; Binh et al, 1990, 1992,
1993) ve tinh dn dinh cao tiong sinh trudng va tiem
nang tai sinh cay hoan chinh
ciia
cac te bao tien phdi
Ilia
da thich nghi vdi dieu kien nudi cay in vitro dai
han cd sfress muoi
NaCI
thich hpp. Bien ddng tiong
cau
tnic genome cua te bao lua nudi cay in vitro
cung da dupc ghi nhan qua phan img RAPD vdi cac
ddng
liia

tai sinh tii nhiing ddng md nudi cay ngin
han hon frong cac dilu kien chpn lpc khac
(Ngezahayo et al, 2007; Rasheed et al, 2005; Phan
Thi Bay et al,
2001;
Phong et al,
2001).
Co
chi
cua
hien tuong biln di soma hien cdn chua duoc hieu
biet day du. Tuy nhien, nhiing nguyen nhan cd kha
nang dan tdi bien di soma (Barr, Jain,
1998)
bao
gdm: (1) Thay ddi d
miic
dp nhiem sac the; (2) Dot
bien diem; (3) Su bat cheo va trao ddi doan cua
nhiem sac the chi em; (4) Su tai sap xep vi tri cua
gen; (5) Su bdi nhan DNA; (6) Hoat ddng cua cac
"gen nhay"; (7) Su methyl hda DNA; (8) Nhiing
thay ddi tiong DNA cua co quan tii; (9) Bien di chiic
nang cua gen,
Nghien cim nay ghi nhan dupc nhiing bien ddng
phan tu tiong genome cua cac te bao
liia
nudi cay in
vitro dai han phu thudc rat nhieu vao dieu kien nuoi
cay frong dd cd stiess mudi

NaCI.
Co che cua hien
tupng bien di soma trong nudi cay in vitro hien van
dang dupc tiep tuc nghien cim.
Ksh
Cn
Co
Hinh
3. Cay
lien
ket dua
tren
cac
chi
thj
phan
tu
(RAPD)
cua hai
ddng
te bao
nudi
cay in
vitro
dai han
trong
mdi
trudng
khdng
cd

stress muoi
NaCi
(Co) va cd
stress muoi
NaCi
(Cn) vdi cay doi
chiing
(Ksh).
KET LUAN
Mudi
NaCI,
d ndng dp thich hpp nhu 1,5%
NaCI
dung tiong nghien cim hien tai vdi md, te bao cd
ngudn gdc tir hat lua, cd nhiing anh hudng tich
cue
nhat dinh len su dn dinh
ciia
genome te bao - mdt
frong nhiing yeu td quyet dinh de duy fri tinh toan
nang
ciia
chiing frong nudi cay in vitro dai han.
Loi cam
on.
Cdng trinh dupc hodn thdnh vai su hd
tra kinh phi mpt phdn cua di tdi nghien cieu cdp ca
so Viin Cdng nghe sinh hpc vd Quy hpc bdng
UNIDO/ICGEB,
Italy.

TAI
LIEU
THAM
KHAO
Abdullah R, Cocking EC, Thompson JA (1986) Efficient
plant regeneration from rice protoplasts through somatic
embryogenesis. BioTech 4: 1087-1090.
Abe T, Futsuhara Y
(1991)
Regeneration of rice plants
from suspension culture. In: Bajaj YPS (Ed.)
Biotechnol
AgricultFores
14:
3S-45.
Barr DS, Jain SM (1998) Somaclonal variation:
mechanism and application in crop
improvement.
In: Jain
SM, Barr DS, Ahloowalia BS Eds. Somaclonal
Variation
and Induced Mutation in Crop Improvement. Kluver
Academic
Pubhsher:
15-38.
Binh DQ (1995) In vitro selection and
characterization
of
salt tolerant cells in monocotyledonous plants. PhD
Thesis, Hungarian Academy of Sciences, Budapest,

Hungary.
Binh DQ, Heszky LE (1990) Restoration of the
regeneration potential of long-term cell culture in rice
(Oryza
sativa L.) by salt prefreatment. J Plant Physiol 136:
336-340. '•
Binh DQ, Heszky LE,
Simon-ICiss
I
(1990)
Increased plant
238
Tgp chi Cdng nghe Sinh hpc 1(2): 235-240, 2009
regeneration in immature inflorescence tissue culture of
different rice hybrids by
NaCI
used in callus mduction.
Oryza
27:
409-414.
Binh DQ, Heszky LE, Gyulai G, Csillag A (1992) Plant
regeneration of
NaCl-prefreated
cells from long-term
suspension culture of rice (Oryza sativa L.) in high saline
conditions. Plant Cell Tiss Org
Cult
29:
75-82.
Binh DQ, Fabian F, Heszky LE (1993) Responses to

continuous and discontinuous
NaCI
sfress of long-term
cultured rice (Oryza sativa L.) cells. Acta Biologica
Hungarica
44(2-3):
197-210.
Datta K, Potrykus I, Datta SK (1992) Efficient fertile
pknt
regeneration from protoplasts of indica rice breeding line
IR72
(Oryza
sativa L.). Plant
Cell Rep
11:
229-233.
Deka PC, Sen SK (1976) Diffrentiation in calli originated
from isolated protoplast of rice (Oryza sativa L.) through
plating technique.
Moi Gen
Genet
145:
239-243.
Fujamura T, Sakurai M, Akagi H, Negishi T, Hirose A
(1985) Regeneration of rice plants from protoplast. Plant
Tiss Cult Lett
2:
74-75.
Gautheret RJ (1985), History of plant tissue and cell
culture: A personal

account.
In:
Vasil
IK (Ed.) Cell
Culture and Somatic Cell Genetics of
Plants.
Academic
Press,
Inc., New York
2:
1-59.
Gobel E, Ozias-Akins P, Lors H (1985) Cell and protoplast
culture of
rice.
In: Adersen PG, Withers LA (Eds.) Plant
Tissue Culture and Its Agricultural Application.
Butterworth, Kent., 359-365.
.
Ham C (1973) Fusion of protoplast isolated from rice
callus.
SABRAONews
5:
107-110.
Heszky LE, Simon-Kiss I, Binh DQ
(1996)
Release of rice
variety 'DAMA' developed through haploid somaclone
breeding. In: Bajaj YPS (Ed.) Biotechnology in
Agriculture and Forestry. Vol. 36. (Somaclonal variation
in Crop Improvement II.) Springer Verlag, Berlin-

Heidelberg-New York: 46-54.
Jenes B, Pauk J (1989) Plant regeneration from protoplast
derived calli in rice
(Oryza
sativa L.) using dicamba. Plant
Sci
63:
187-198.
Kabir AH,
Mahfiiz
I, Razvy MA, Ahmed MB, Alan MF
(2008) Indirect organogenesis and somaclonal variation in
four rice cultivars of Bangladesh.
/
Appl Sci Res 4(4):
451-458.
Kavi'ata
S, Ishihara A (1968) The regeneration of rice
plant, Oryza sativa L., in the callus derived from the
seminal root.
Proc Jpn
Acad
44:
549-553.
Larkin PJ, Scowcroft WR (1981) Somaclonal variation-a
novel source of variability from cell cultures for plant
improvement. Theor Appl
Genet
60:
197-214.

Lestari EG (2006) In vitro selection and somaclonal
variation for biotic and abiotic sfress
tolerance.
BIODIVERSITAS 7
(3):
297-301.
Maeda E (1968) Subculture and organ formation in the
callus derived from rice embryos in vitro. Proc Crop Sc
Jpn 37: 51-58.
Murashige T, Skoog F
(1962)
A revised medium for rapid
growth and bioassays with tobacco tissue cultures. Physiol
Plant
15:
473-497.
Ngezahayo F, Dong Y, Liu B (2007) Somaclonal variation
at the nucleotide sequence level in rice
(Oryza
sativa L.) as
revealed by RAPD and
ISSR
markers, and by pairwise
sequence analysis. J Appl
Genet 48
(4): 329-336.
Nishi T, Yamada Y, Takahashi E (1968) Organ
redifferentiation and plant restoration in rice callus. Nature
219:
508-509.

Nghiem Nhu Van (1983) Tao cay liia luang bgi
tir
md seo
nhan tii than cay dan
bpi.
Tgp chi Sinh
hoc 5(3): 16-17.
Phan Thi
Bay,
Le Thi Mudi, Nguyin
Diic
Thanh (2001)
Nhiing bien ddi phan tir d cac ddng
liia
khang dich nam
gay benh dao dn Pyricularia oryzae. Tgp chi Sinh hoc
23(2):
32-38.
Phong DT, Muoi LT, Binh LT (2001) RAPD variability in
rice (Oryza sativa L.) plants derived from desiccation-
tolerant calli.
Euphytica
121:
297-303.
Rasheed S, Fatima T, Husnain T, Bashir K, Riazuddin S
(2005) RAPD characterization of somaclonal variation in
indica Basmati rice.
Pak J
Bot
37(2):

249-262.
Rohlf
FJ (1993) NTSYS-pc Numerical taxonomy and
multivariate system. Version 1.80. Applied Biostatistics
Inc.,
New York.
Scowcroft WR (1985) Somaclonal variation: the myth of
clonal uniformity. In: Bohn B, Denis ES (Eds.) Plant Gene
Research, Genetic-fluxes in Plants. Springer, Berlin
Heidelberg New York
Tokyo:
217-245.
Sfreet HE (1957) Excised root culture. Biol Rev 32:
117-
155.
Tamura S (1968) Shoot formation in calli originated from
rice embryo.
Proc
Jpn Acad
44:
543-548.
239
Nguyen Thanh Thiiy & Dd Quang Binh
EFFECTS OF
NACI
STRESS ON THE GENOME STRUCTURE STABILISATION OF
RICE
ORYZA SATIVA
CELLS LONG-TERM CULTURED IN
VITRO

Nguyen Tbanb
Tbuy,
Do
Quang
Binb*
Institute
of Biotechnology
SUMMARY
In vitro culture of plant cells is a useful tool for studies relating the biological fransformation from a single
cell to the whole plant in vitro. Using the in vitro technology, researchers are able to not only confrol the
biological reaction chains but also to create a number of new products other than those
ofthe
initial materials.
However, growing in the in vitro artificial conditions for a long time, plant cells could not avoid the
phenomenon of soma variation. The level of variation of the cultured cells depends on various factors,
including the genotype and physiological state of initial materials, the culture conditions, the culture time, etc.
This study presents results relating the molecular changes in the genome of rice (Oryza sativa) cells that have
been cultured for a long time in different salt
(NaCI)
sfress conditions by RAPD technique. In comparison with
the initial material, not derived from the culture in vitro of isolated cells, genome of cells cultured in a
condition without
NaCI
sfress bears more molecular changes than that of
cells
continuously cultured in the salt
sfress condition. Though cells of the two culture conditions shared several specific changes, induced by the
long-term culture in
vitro,
the salt sfress adapted cells shared more common similarities with the initial material

than the non sfressed cells. Results obtained from the present study are in accordance with our previous
observations, carried out at the cell level, that the totipotency
ofthe
isolated rice cells has been stabilized much
better in the suitable salt sfress culture condition than in the condition without the sfress factor.
Keywords:
Differential
variation,
genome
stability,
long-term
cell
culture,
NaCI
stress,
Oryza
sativa
Author for correspondence: Tel: 84-4-38363470; Fax: 84-4-38363144; E-mail:
dqbinh&.ibt.ac.vn
240