Xác định các chỉ thị AFLP đặc trưng cho bảy dòng cá rô phi nuôi ở Việt Nam

Tgp chi Cdng nghi Sinh hgc 7(4): 455-462, 2009

XAC DINH CAC CHI THI AFLP DAC TRLTN G CHO BAY DONG CA RO PHI NUOI d

VIET NAM

Trin Thj Bich Hong', Nguyin Thi Td Nga', Ngo Thj Kim', Quyen Dinh Thi', Nguyin Hfru Ninh^ Pham

Anh Tuin^

'Vien Cdng nghi sinh hgc

^Viin Nghiin cim nudi trdng Thiiy sdn I

TOM TAT

Bay ddng ca rd phi nguyen lieu ngoai nhap tir cac nudc khac nhau thupc 2 loai Rd phi xanh (Oreochromis

aureus) va Rd phi van (Oreochromis niloticus) dugc sir dung de nghien cim tinh da dang di truyen, tim marker

AFLP phan biet cac ddng ca rd phi. DNA cua 7 ddng dupc ghep vdi muc dich giam sd lugng mau ma khdng

anh hudng den chat lugng, muc dich nghien cim. Sir dung NTSYSpc cho thay he sd tuong dong giira cac ddng

rat cao > 0,85, dac biet la giira cac ddng Rd phi xanh hoac giira cac ddng Rd phi van (> 0,97). Cd 13/16 td hgp

mdi deu the hien su khac nhau giiia Rd phi van va Rd phi xanh ve mat di tmyen va 6 td hgp mdi xuat hien bang

dac trung cho mot so ddng. Vdi tdng sd 375 bang thu dugc (tmng binh mdi td hgp mdi co 23,4 bang), chi cd 64

kieu bang da hinh trong do 40 bang cd the dung nhan dang Rd phi xanh hoac van va 12 bang dac tnmg cd the

dung nhan 7 ddng nhu: AF25/220, AF26/210, AF26/350, AF29/330, 'AF42/180, AF42/170, AF43/170,

AF43/225, AF43/250, AF43/160, AF54/125, AF54/180. Day la cac bang dac trung cd thg dung lam nguyen

lieu cho viec phat trien cac chi thi phan tir trong chpn gidng d ca rd phi.

Tit lihoa: AFLP, bdng dac trung, Oreochromis aureus, Oreochromis niloticus, ro phi

MODAU

Ca rd phi d Viet Nam cd rat nhieu loai nhu Rd

phi van {O. niloticus), Rd phi xanh {O. aureus), hay

Rd phi den {O. mossambicus). Do ddng Rd phi den

(nhap tir Philippines) de qua day, lai cham ldn, kich

thudc ca the bi giam dan, nen ddng rd phi nay khdng

dugc phat trien. Trudc day, vdi dieu kien canh tac d

Viet Nam, viec luu giir gidng thuan khdng bi tap

giao giiia cac ddng la van de rat khd khan cho cac

nha chgn gidng ca rd phi. Hien tugng tap giao cua

gidng gdc vdi cac loai rd phi dai la mdt trong nhiing

nguyen nhan lam giam nang suat va chat lugng cua

mua vu frong nudi trdng thuy san. Kinh nghiem ciia

cac nha nudi trdng thuy san cho thay neu mudn nudi

cd hieu qua thi phai giii dugc chat lugng ddng thuan,

ddng thdi nghien cim tim bien phap nang cao chat

lugng di truyen cua chiing va kha nang thich iing vdi

dieu kien nudc ta thdng qua qua trinh chgn gidng

(Dd Diic Hanh, 2006).

Cac nhdm tac gia nhu Quyen Dinh Thi, Nguyin

Thi Dieu Thiiy, Nguyen Van Cudng (Nguyin Thu

Thiiy et al, 2004; Quyin Dinh Thi et al, 2004;

2005), Nguyen Huu Ninh, Pham Anh Tuin (2003)

mdi chi sir dung microsatellite, AFLP, RAPD budc

diu danh gia da hinh hay mdi quan he di truyin giiia

cac dan ca nhim tim kiem cac rnarker lien kit gidi

tinh, huylt thdng va pha he (Quyin Dinh Thi, Pham

Anh Tuin, 2005). Cac ddng thuan dugc luu giii chu

yeu d cac trung tam gidng. Rd phi canh tac la cac

ddng lai tao cd dugc tir cac chuang trinh chgn gidng

Norivay nhu NOVIT 1, 2, 3... dugc tao tu ddng rd

phi bd me GIFT (Genetic Improvement of Farmed

Tilapia, 1994) (Le Thanh Lim, 2000). Trong cdng

tac chgn gidng, chii yeu nghien ciiu tim kiem rd phi

sinh trudng tdt frong cac dieu kien Viet Nam theo

hudng lai tao cac ddng hien cd de tim cdng thirc lai

cho ty le gidi tinh due cao (Pham et al, 2002) hay cd

tdc do sinh trudng tdt d vimg nudc lg man (Pham

Anh Tuan et al, 2008), nang cao sire sinh trudng va

kha nang chiu lanh bang chgn lgc gia dinh (Nguyen

Cdng Dan et al, 2003). Tuy nhien, cac nha chgn

gidng van khdng ngimg tim kiem cac ddng rd phi

mdi cho hieu qua san xuat cao tu cac ddng thuan sir

dung phuang phap lai khac loai.

Tren the gidi, cac nghien cim AFLP tap trung

chil yeu d mdi quan he di truyen, danh gia tinh da

hinh quan the (Koeher et al, 1998). Marker phan tit

ra ddi da phan tich true tiep vat lieu di truyen DNA

dem lai do chinh xac cao frong viec danh gia va xac

dinh cac ddng, loai ca. Mdt sd tac gia nhu Franck,

Rutten, Penman va McAndrew... da sir dung

microsatellite de nhan dang, xac dinh loai va liet ke

mdt loat cac vi tri du doan lien quan chat che vdi cac

allele khac nhau giiip phan biet giira cac loai chu yeu

va ddng lai (Franck et al, 1992; Penman, Mcandre'w,

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