Tit 20: To ging bng phng php gy t bin v cng ngh t boI. To ging bng phng php gy t binTi sao li phi to ra ging mi bng phng php gy t bin? Nu khng lm c c khng?

c s khoa hc ca vic gy t bin to ging mi

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Mi mt kiu gen nht nh ca ging ch cho mt nng sut nht nh. - Mi ging c th s cho mt nng sut ti a nht nh trong iu kin canh tc hon thin nht. Mi ging c mt mc trn v nng sut. - c nng sut cao hn mc trn hin c ca ging, cn gy t bin bng vic s dng cc tc nhn vt l v ho hc, lm thay i vt liu di truyn ca sinh vt, chn lc t cc th t bin nhng c th c c tnh mong mun.

Nghin cu mc I.1, em hy cho bit: - Gy t bin l g? -Quy trnh gy t bin? -i tng p dng?

* Khi nim: Gy t bin l i mi vt liu di

truyn ca ging c

quy trnh to ging mi bng phng php gy t bin

a) X l mu vt bng tc nhn gy t bincn la chn tc nhn gy t bin thch hp,

Tm hiu liu lng v xc nh thi gian x l ti u

b) Chn lc cc th t bin c kiu hnh mong mun Ti sao li phi tin hnh la chn cc th t bin thch hp ? c) To dng thun chng

* i tng thch hp ch yu l: vi sinh vt v thc vt.- Vi sinh vt sinh sn bng cch phn i nn khng th to BDTH, BDDT vi sinh vt ch yu c to ra nh t bin. vsv c tc sinh sn nhanh nn chn lc v nhn cc th t bin d dng hn - Thc vt: thch hp vi vic khai thc cc sn phm l c quan sinh dng nh; r, thn, l, hoa,.. to ging a bi. Cn cy ly ht th khng th to ra a bi v cy a bi thng b gim kh nng sinh sn hoc bt th. - ng vt bc thp; c th gy t bin, v d; rui gim, tm,.. - ng vt bc cao th khng p dng phng php ny v; h gen ca chng rt phc tp, phn ln cc t bin u lm mt cn bng h gen dn n nhng ri lon v sinh l nn gim sc sng, gim kh nng sinh sn, thm ch cn gy cht

2. Mt s thnh tu to ging Vit Nam Gy t bin bng tc nhn vt l: Ging la Mc tuyn t bin MT1 c nhiu c tnh qu (chn sm nn rt ngn thi gian cach tc), thp v cng cy, chu chua v phn nn c th trng nhiu vng khc nhau, nng sut tng 15-25%. To ging Ng DT6: chn sm, nng sut cao, hm lng Pr tng 1,5%..

-Gy B bng tc nhn ho hc: To gia lc x l bng NMU (nitr mtyl ur) to m hng cho 2 v qu/nm, khi lng qu tng cao v thm ngon. Cy du tm (3n) c nhiu c tnh qu: bn l dy, nng sut cao. Da hu v nho (tam bi) u khng c ht v nng cao hm lng ng

Da hu tam bi

Th t bi du ty

Vi kin thc hc, em hy xut cch thc nhn bit s b cc cy t bi trong s cc cy lng bi?

II. To ging bng cng ngh t bo

Cng ngh t bo

Cng ngh t bo thc vt Cng ngh t bo ng vt

1. Cng ngh t bo thc vt

Nui cy m

Cng ngh t bo Thc vt

Nui cy ht phn

Dung hp t bo trn

Nui cy t bo (M) Da vo kh nng to m so l m gm nhiu t bo cha bit ho, c kh nng sinh trng mnh t iu khin cho t bo bit ho thnh cc m khc nhau (r, thn, l...) v ti sinh thnh cy trng thnh. Da vo vic tm ra mi trng nui cy chun kt hp vi vic s dng cc cht hoocmn sinh trng nh auxin, giberilin, xitokinin... K thut ny cho php nhn nhanh cc ging cy trng ng nht v kiu gen c nng sut cao, cht lng tt, thch nghi vi iu kin sinh thi nht nh, chng chu bnh tt ...

Dung hp t bo trn

Hai t bo loi v xenlulz ca 2 loi khc nhau c kh nng dung hp. T bo cht v 2 khi nhn u hp nht thnh mt. Lai t bo xma (sinh dng) c bit c ngha v ging mi mang c im ca c hai loi m bng cch lai hu tnh khng th thc hin c.

Nui cy ht phn (non cha th tinh) Ht phn c th "mc" trn mi trng nui nhn to thnh dng t bo n bi. S a dng ca cc giao t do gim phn to ra cho php chn lc c cc dng t bo c b gen n bi khc nhau da vo s biu hin thnh kiu hnh ca cc alen ln. c ging cy trng cho canh tc th cn lng bi ho cc dng n bi ny (x l ho cht cnsixin) cy lng bi hon chnh, c KG ng hp t v tt c cc gen. u im ni bt ca phng php l cc ging cy trng nhn c u thun chng V d to ging la chim chu lnh ngi ta trc tip nui ht phn mi trng lnh. Kh nng chu lnh ca ht phn c th do gen t bin, do t hp gen mi.

2. Cng ngh t bo ng vt

Cng ngh t bo ng vt

Nhn bn v tnh

Cy truyn phi

a. Nhn bn v tnh ng vt

Thnh

cng ny chng t, trong thc nghim, ng vt c v c th c nhn bn t t bo xma, khng cn c s tham gia ca nhn t bo sinh dc, ch cn cht t bo ca mt non bo. Nhm nhn nhanh ging vt nui qu him hoc tng nng sut trong chn nui. K thut ny cn cho php to ra cc ging ng vt mang gen ngi, nhm cung cp c quan ni tng ca ng cho vic thay th, ghp ni tng cho ngi m khng b Nhn bn v tnh v ngi loi ng dng: v d, nu ta c 1 con h min dch ca c nhiu thi.ging c nhiu c im qu th ta c th to ra nhiu con vt c kiu gen nh vy. Tuy nhin nhn bn v tnh ng vt mi ang trong giai on nghin cu th nghim 1 s loi ng vt. v ngy nay vn ang tip tc c hon thin v p dng cho nhiu loi ng vt khc nhau. K thut ny c bit c ngha trong vic nhn bn ng vt bin i gen

b. Cy truyn phiNguyn tc chung ca phng php: da vo s pht trin ca phi t 1 t bo ban u (hp t)Cc ging ng nht v kiu gen

Cy truyn phi

Nhn nhanh ging

Ci bin phm cht ca ging

Cu 1: Chia ct mt phi ng vt thnh nhiu phi, ri cy vo t cung ca cc con ci khc nhau t nhanh chng to ra hng lot con c kiu gen ging nhau c gi l phng php: a. b. c. d. Nui cy hp t. K thut chuyn Cy truyn phi Nhn ging t bin

Cu 2:Trong k thut lai t bo, cc t bo trn l:a. cc t bo xma t do c tch ra t m sinh dng b. cc t bo c x l lm tan mng sinh cht c. cc t bo c x l lm tan thnh t bo d. cc t bo khc loi ho nhp tr thnh t bo lai

Cu 3: Mc ch ca vic gy t bin vt nui v cy trng l:a. to ngun bin d cho cng tc chn ging b. lm tng kh nng sinh sn ca c th c. lm tng nng sut vt nui, cy trng d. a, b, c