Đa dạng di truyền virus thuộc chi Begomovirus trên cây thuốc lá ở Việt Nam

Tgp chi Cong nghg Sinh hgc 12(1): 133-141, 2014

DA DANG DI TRUYE N VIRU S THUQ C CHI BEGOMOVIRUS TRE N CA Y THUO C LA

d VIET NA M

Nguy?n Van Doai, Pham Th} Van, Chu Hoang Ha, Le Van Sofn

Vi^n Cdng nghe Sinh hoc, Vien Hdn ldm Khoa hgc vd Cong nghe Viet Nam

Ng^y nhan bai: 26.02.2014

Ngay nhan dang: 20.3,2014

T 6M TAT

Begomovirus la chi Idn nhat Uong hp Geminivindae dang gay thiet hai nghiem trong tdi nang suat va chat

luong cho nhiSu c3y trong 6 Vi^t Nam, trong S.6 c6 thufle Id Viec ph6ng va trtr benh gap nhieu kho khan do

kha nang ISy nhiem vii miic do da dang di tmyen cung nhu kf chii ciia nhom virus nay. Vi vay, cac nghign ciiu

v6 da dang di tniyen la van de cap thiet trong cong tac phong va ch6ng tdc hai cua virus nay gay ra. Trong

nghien cihi niy, vDng gen Vf ma h6a cho protem vo cua Begomovirus tir cac mau benh ihuoc Id thu thap tai

m$t s6 vimg chuyen canh d Mien Bac va Mien Nam da dugc phSn lap va xac dinh tfinh tu. Ket qua phan n'ch

trinh tu va danh gia da d^ng di iruySn thdng qua ciy phdt smh chung loai ciia 26 the phan ISp da phar hien su

CO mjt cila 5 lo^ virus thupc nhom Old World trong chi Begomovirus, gom- Ageralum yellow vein virus,

Papaya leaf curl China virus, Pouzolzia golden mosaic virus. Tomato yellow leaf curl Kanchanaburi virus,

Ludwigia yellow vein virus. Dp tuong d6ng ve trinh tu nucleotide giua cdc the phan lap Uong mpt loai dao

d^ng tir 88 - f 00%, Uong Idii, giiia cac loai so vdi nhau dao dong tu 69 - 88% da chiing to sir da dang di tmySn

ciia Begomovirus gay bSnh tr6n thuoc Id d Viet Nam.

Tir khoa: Begomovirus, da dang, gen VI, thuoc la, v s thut

MODAU

Begomovirus la mot trong bdn chi ldn nhat trong

hp Geminiviridae vdi tren 200 loai khac nhau

(Fauquet et ai, 2008). Virion cd dang hinh chiiy

gdm hai khdi c3u 20 mat, kich thudc khoang 38x22

nm. Cdc virus trong chi Begomovirus duac chia Iam

3 nhdm chfnh dira vao cau triic genome cua chiing

hao gdm logi hai vdng gen (DNA-A va DNA-B) kfch

thudc khoang 2,6 - 2,8 kb (th^ bipartite), loai mot

vdng gen nhung dich ma thanh hai khung dpc rieng

bi?t (gi6ng DNA-A) kich thudc khoang 2,8 kb (Ihl

monopartile) va loai mpt vdng gen kem DNA ve tinh

(Chowda el al., 2005; Idris & Brown, 2006; Ha et

fl/., 2008).

Genome Begomovirus cd 6 khung dpc md, gdm

gen CP (VI) vapreCP (V2) cd chi6u dich ma nguac

chi^u vdi bdn gen Cl, C2, C3 va C4. Cac gen nay cd

th^ nam trSn cting mpl vong DNA-A hoac hai vdng

DNA-A vh DNA-B rieng biet dupc ngan each vdi

nhau bdi mpt vimg lien gen (IR-intergenic region) cd

dO d&i khoang 200 nucleotide, Tren dd chiia di6m

khdi dSu sao ch6p v& vimg dilu khien cho su Iai ban

vdng gen virus theo ca hai hudng. Dang trinh nr dien

hinh nhat trong vimg IR la hai Irinh tir bao thu lap lai

dio ngupc ciia TAATATTAC dupc dinh vi uen mpl

cau tnic vong (stem-loop) cd lien quan tdi viec tai

ban spi DNA mdi va mot trinh tu lap can thiet cho

viec nhan biet va bam vao ciia protein Rep uong qua

trinh phien ma (Lazarowilz et al., 1992; Rojas et al.,

2005; SeaU/«/, 2006))

Dira vao he Ihdng phat sinh lo^ va su sap xep cac

gen Uong genome, Begomovirrus dupc chia \km hai

nhom chfnh: (I) nhdm OldWorld (OW) gom nhijng

virus cd nguon goc phal smh tir cac viing Ddng ban

ciu, Chau Phi, Chau Au va mot so khu vuc thupc

Chau A; va (2) nhdm virus NewWorld (NW) c6

ngudn goc phat sinh d Tay ban can va Chau My

(Padidam et ai, 1999). H^u het cac loai trong

Begomovirrus phan lap d Viet Nam thupc nhdm OW.

Khi xam nhiem, tuy khong lam chet cay, nhung

tac hai do virus thudc Begomovirus rat ldn. Hau het

khi lay nhiem, cay chu thudng bieu hien cac tiieu

chiing nhu cdi cpc, quan vang la va cd the chet neu

dilu kien s6ng khdng t6l. Nang suat va pham chdt

nong san bi suy giam Vf du, benh xoan vang la do

Tomato yellow leaf curl virus va xo5n la do Tomato

leaf curl virus cd thl lam giam 55 - 90% nSng suat

ca chua nlu bi ISy nhilm (Reynaud et ai, 2003) Neu

cay nhilm vuus sdm thudng khdng ra qua vi hoa bj

rung sdm.

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