I MUC TIEU
Hgc xong bai nay, hgc sinh phai :
- Giai thfch dugc eo sd sinh hgc ciia cac phuong phap nhan gidng vd tfnh (nhan gidng sinh dudng) : ehilt canh, giam canh, ghep canh, ghep ehdi (mat).
- Neu dugc Igi fch kinh te ciia phuong phap nhan gid'ng vd tfnh.
- Thuc hien duge cac phuong phap nhan gid'ng vd tfnh : giam canh, ghep canh va ghep ehdi (mdt).
II CHUAN Bj
1. Gidm ednh vd gidm Id
- Mdu vat : cay Id bdng, cay sdn, day khoai lang, rau mud'ng, cay dau.
rau ngdt,...
- Dung eu : dao, keo dl edt canh ; chau (hay ludng) ddt dm.
2. Ghep cdy
- Mdu vat : cay dao, eay xoai non 1- 2 nam tudi, cay cam, budi,...
- Dung cu : dao, keo sde dl rach vd cay va edt than cay, day nilon.
III - NOI DUNG VA CACH TIEN HANH 1. Gidm ednh vd gidm Id
- Gidm canh
Cat than cLia mdt trong cac cay sdn, rau ngdt, cay dau, khoai lang, rau mudng,...
thanh nhieu doan (hom), mdi doan dai chimg 10 - 15cm va cd sd lugng cac choi (mdt) bang nhau. Dem cac hom edm nghieng cho dau dudi vao dat dm, mot phan hom d tren mat dat.
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Theo ddi su nay ehdi va tdc do sinh trudng cua cay mdi sinh ra tir edc hom khdc nhau xuat phdt tir ciing mdt than cay. Ket qua quan sat ghi vao bang dudi day va tu dd riit ra nhan xet vl kha nang nhan gid'ng sinh dudng ciia cac phdn khdc nhau tren than eay me.
V| tri ciia hom tren cay me ke tii dinh
1
0
3 4 5
Sd choi da nay
Ngay Chieu dai cua choi
(cm)
j
Danh dau x vao 6 chi hom cd choi
dai nhat
1
1
i 1
1
Kit luan : ghi phan than nao cd khd nang nhan gid'ng sinh dudng tdt nhat.
Gidi thich vi sao.
- Gidm Id
edt mdt Id cay la bdng (la banh te) rdi dat nd xudng ddt dm. Tlieo ddi su xuat hien cdc cay mdi tir mep eiia philn Id.
2 . Ghep ednh
Dung dao sdc edt vat. ggn va sach gde ghep va canh ghep dl cho bl mat tie'p xuc eua ednh ghep dp that sat vao mat vat ciia gd'c ghep. Cdt bd tat ca cdc Id cd trdn canh ghep vd loai bd bdt chung 1/3 sd Id trdn gd'c ghep. Tiep theo phdi bude that chat canh ghep vdi gd'c ghep dl cho ddng maeh gd dl ddng di ehuyin tir gde ghep ldn ednh ghep (hinh 43).
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GHEP C A N H
Canh ghep tii 1 cay Cat gon, sach
Canh ghep
i '' duac day buoc chat vao g6c ghep j \ giup lien ket tdt
Tang phat sinh cua ca canh ghep va goc ghep sinh truong tao nen su lien l<et giua chiing
GHEP CHOI Cat rdi mat ngoai cua v6 vdi choi
,. • GOC f GHEP
1 f •
<
Cat dang T tren goe ghep
f
Choi ghep duac dat vao phan eSt
:, -ra,... ^ : - ^ , ,
Dat cho vi tri va
i ghep vao buoc day
,j
1
. a *
•4.
Vr-^y },
^
M6 seo tao nen tai cho ghep hinh thanh mach go va mach ray noi hai phan (goc ghep va choi ghep), phan v6 phia tren choi bj cat bo di trudc l<;hi nay choi
Hinh 43. Ghep canh va ghep choi (mat)
3. Ghep choi {mdtl
Rach ldp vd tren gd'c ghep thdnh hinh chii T (d doan than mudn ghep) dai khoang 2cm. Dung sdng dao tdch vd theo vet rach mdt khoang dii de dat mdt ghep.
Chgn mdt choi mdi nhii trdn canh ghep (ehdi ngii) lam ehdi ghep. Dung dao sdc cat ggn ldp vd kem theo mdt phdn gd d chan mdt ghep.
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Oat mat ghep vao chd da nay vd, sao cho ldp vd eua gd'c ghep vd ehdi ghep sat nhau d dau chirT. Vd eua gde ghep phu len vd ciia ehdi ghep. Bude dp vd gd'c ghep vao ehdi ghep va de cho phdn gd eiia ehdi ghep dp sat vao phdn gd ciia gde ghep giiip cho ddng mach gd di chuyin dl dang tir than gde ghep sang ehdi ghep. Chii y khdng bude de len choi ghep (hinh 43).
IV - THU HOACH
Mdi hgc sinh phai :
- Lam bai tudng trinh vl thuc hanh giam canh, ghi bang theo ddi thuc hanh va ket luan da rut ra duge.
- Tudng trinh vl thuc hanh ghep canh va thuc hanh ghep ehdi mdt.
Lam thuc hanh theo nhdm tu 5 - 6 hgc sinh de tien hanh giam canh va giam la d nha hoae tai vudn trudng (neu cd). Mdi nhdm tien hanh giam canh eiia mdt lodi cay, mang den ldp kit qua gdm cdc hom da ed ehdi dang sinh trudng va bdng sd lieu theo ddi dugc. Mdi nhdm dgc nhan xet ciia nhdm minh cho cac nhdm khdc ghi.
Cac nhdm tren thuc hien ghep canh va ghep ehdi mat tai trudng, dudi su hudng ddn true tiep ciia giao vien.
* Nlu ed dilu kien : thay bai thuc hanh bdng bdi tham quan co sd nghien ciru hay san xuat cd tiln hanh nhan gid'ng vd tfnh (lai, ghep, giam, chiet canh, nudi cay md thuc vat).
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