BO CONG THUONG yv"- CONG TY CO PHAN BONG MIEN BAC ^ bkO cAo TONG \<it "NGHIEN cou ANH HI;6NG COA BIEN PHAP sCr DUNG inudc TRCT c6 Bin Hieu QUA CCiA viec TR6NG BONG XEN DAU XANH TAI BAC GIANG" Thuc hien theo Hgp ddng sd 119.09 RD/HD-KHCN ky ngay 04 thang 03 nam 2009 gii!a Bg Cong thuang va Cong ty Cd phan Bong Mien Bdc Ca quan chu tri: Cong ty Co phan Bong Mien Bac Chu nhiem 6e tai: KS. Pham Van Phu Can bo chinh tham gia thi/c hien: KS. Vu Van Bo KTV. Pham Ngoc Hung Ha Noi, thang 12 nam 2009 MUC LUC • • Noi dung Trang Phin I - Md diu 1 1.1. Dat van de 1 L2. Muc dich, yeu cau cua de tai 2 1.2.1. Muc dich 2 1.2.2. Yeuclu 2 Phan II - Tdng quan tai lieu 3 2.1. Mgt sd NC ve anh hudng cua dieu kien khi hau, dat dai den cay bdng 3 2.2. Mgt sd nghien cuu ve anh hudng cua thdi vu den cay bdng 5 2.3. Nhiing nghien cuu ve anh hudng cua mat do gieo trdng tren cay bdng 6 2.4. Mgt sd ket qua nghien cuu ve anh hudng cua phan bdn den cay bdng 6 2.5. Mgt sd nghien cuu ve luan canh, xen canh, gdi vu 7 2.6. Mgt sd nghien cuu su dung thudc trir cd trong canh tac bdng 11 Phan III - Vat lieu, ndi dung va phuang phap nghien cuu 14 3.1. Vat lieu nghien cuu 14 3.2. Ngi dung nghien cuu 15 3.3 Phuang phap nghien cuu 16 Phan IV - Ket qua nghien cuu va thao luan 22 4.1. Mgt sd yeu td khi tugng tai huyen Luc Ngan tir thang 4-11 nam 2009 22 4.2. Nghien cuu thanh phan va muc do phd bien cd dai tren rudng bdng tai Luc Ngan 23 4.3. Danh gia hieu lire ciia thudc trir cd Glyphosan 480 DD, Giy up 480SL va Ka nup 480 SL 25 4.3.1. Anh hudng ciia lugng thudc phun den thdi gian cd chet va mgc trd lai 25 4.3.2. Anh hudng cua thuoc Kanup 480 SL, Glyphosan 480 DD, Giy up 480 SL d cac lugng phun khac nhau den mat do va khdi lugng cd tuai sau phun thudc 26 4.4. Danh gia hieu lire cua mdt sd loai thudc trir cd vdi sd lan phun khac nhau tren rudng bdng trdng xen dau xanh tai Bac Giang 29 4.4.1. Anh hudng cua sd lan thudc trir cd Ka nup 480 SL, Glyphosan 480 DD, Giy up 480 SL den ty le nay mam va sinh trudng, phat trien cua cay bdng Udng xen 30 4.4.2. Mirc do nhiem mgt sd loai sau benh chinh tren cay bdng va cay dau xanh trdng xen khi sd lan phun thudc trir cd thay ddi 32 4.4.3. Anh hudng cua sd lan phun thudc trir cd den cac yeu td cau thanh nang suit va nang suat cay bdng 34 4.4.4. Hieu qua KT cua bdng trdng xen dau xanh cd sir dung thudc trir cd 35 4.5. QTKT trdng bdng xen dau xanh ket hgp sir dung thudc trir cd 2 lan 39 Phan V - Ket luan va de nghi 41 5.1. Kit luan 41 5.2. Dl nghi 41 Tai lieu tham khao 43 Cac phu luc 47 THONG TIN CHUNG VE DE TAI I. Ten de tai: Nghien curu anh huong cua bien phap sur dung thuoc trir c6 den hieu qua cua viec trong bong xen dau xanh tai Bac Giang. 2. Ma so: 2. Tho-i gian thye hien de tai: Tir thang 01/2009 den thang 12/2009 3. Ho va ten chu nhiem de tai: Pham Van Phu Hoc ham, hpc vi, chuyen mon: Ky su Nong hoc Chuc vu: Dien thoai: 0983.207759 4. Tong kinh phi thye hien: 100.000.000 dong Trong do: - Ngan sach SNKH: 100.000.000 dong - Thu hoi: 0 dong 5. Cff quan chu tri: Cong ty Co phan Bong Mien Bac Dja chi: So 6 Nguyen Cong Trir - Ha Npi Dien thoai: 04.39722132 6. Cff quan phoi hffp chinh: Stt 1- 2- 3- Ho va ten Pham Van Phii Vu Van Bp Pham Ngpc Hiing 7. Danh sach nhirng ngirffi thye hien chinh Hoc ham, hoc vj chuyen mon Ky su Nong hpc Ky su Nong hpc Ky thuat vien 8. Noi dung ciia de tai - Thi nghiem 1: Dieu tra thdnh phdn co dgi tren ruong bong trong a Bdc Giang. - Thi nghiem 2: Ddnh gid hieu luc ciia 3 thuoc trir co Kanup 480 SL, Glyphosan 480DD, Giy up 480 SL vdi cdc lugmg su dung khdc nhau tren ddt trong bong tgi Bdc Giang. - Thi nghiem 3: Ddnh gid hieu qud ciia 3 thuoc trie co Kanup 480 SL, Glyphosan 480DD, Giy up 480 SL vdi so ldn phun khdc nhau tren ruong bong trong xen ddu xanh tgi Bdc Giang. 9. Muc tieu cua de tai - Giiip ndng dan biet su dung thudc trir cd trong trdng bdng xen dau xanh. - Tang he sd sir dat, nang cao hieu qua kinh tl tren dien tich canh tac thdng qua trdng xen bdng vdi dau xanh, tir dd gdp phan md rdng dien tich san xuat bdng tai Bac Giang. Nghien cu'u anh hi/dng cua bien phap sCtdtjng thuoc trCtco den hieu qua cua viec trong bong xen dau xanh tai Bac Giang Phan 1-Md DAU 1.1. Dat van de Bdng la cay cdng nghiep ngan ngay, cd kha nang chiu han kha cao, nil ro trong san xuat thap, nhat la nhimg viing san xuat phu thugc hoan toan vao dieu kien nudc trdi. O cac tinh phia Bac cay bdng trdng chu yeu d viing mien niii, viing ddng bao dan tgc thieu sd, tren cac chan dat ddi, niii ddc, nai it cd dieu kien tham canh dau tu phan bdn. O day, do tap quan du canh, du cu va thdi quen canh tac quang canh cua ddng bao mien niii nen da lam sdi mdn rira trdi dat, dan den tinh trang suy thoai dat ndng nghiep nghiem trgng. Viec di tim dien tich canh tac mdi tdt ban la nguyen nhan chinh dan den tinh trang chat pha rirng. De ban che viec pha rirng va dn dinh san xuat la mdt chu truang ldn cua Dang va Nha nudc. Trong nhimg nam gan day cay bdng da giiip nhieu hd ndng dan mien niii xoa dugc ddi, giam ngheo, nhieu gia dinh da mua sam dugc xe may, ti vi tir viec trdng bdng De cd the dap ung dugc yeu cau phat trien kinh te ndng thdn mien niii va nhu cau ve sgi ngay cang ldn cua nganh Det - May thi viec ap dung cac bien phap ky thuat tien tien, nham nang cao nang suat va hieu qua kinh te cay bdng la het sue can thiet. Bac Giang la tinh cd dien tich dat ndng nghiep ldn, chu yeu la dat ddi ddc da qua su dung nhieu nam, trinh do san xuat cua ngudi dan kha cao, cd kha nang tiep thu cac tien bd ky thuat mdi. Tai huyen Luc Ngan, nai cd dien tich dau xanh tuang ddi ldn. Day la cay trdng cd thdi gian suih trudng ngan, nhung cho thu nhap kha cao, ddng thdi trdng dau xanh cd tac dung ldn trong cai tao dat. Tuy nhien cd nhimg nam gap mua ldn keo dai trong thdi ky thu hoach thi nang suit cay do giam dang ke (50-60%). Tir nam 2004 tdi nay, cay bdng dugc dua vao 1 Cong ty co phan Bong Mien Bac Pham Van Phu Nghien CL^U anh hu'dng cua bien phap su'dung thuoc trifco den hieu qua cua viec trong bong xen dau xanh tai Bac Giang trong tai cac xa San Hai, Phong Minh da dem lai ngudn thu nhap dang ke cho ngudi ndng dan. De nang cao hieu qua kinh te tir viec trdng bdng tai Luc Ngan, thi viec trdng xen bdng vdi do xanh la mdt trong nhimg bien phap ky thuat dugc lua chgn nham: tang he sd sir dung dat, cai tao dat, md rdng dien tich trdng bdng, dong thdi ban che nii ro cho cay do xanh. Vdi dien tich gieo trdng ldn, thi cdng lao dgng thdi vu nhu chuan bi dat gieo, lam cd, cham sdc la mdt van de cap bach can phai dugc giai quyet. Xuat phat tir yeu cau tren chiing tdi tien hanh nghien cuu de tai: ''Nghien ciru dnh hu&ng ciia bien phdp su dung thuoc trir co den hieu qud cua viec trong bong xen do xanh tai Bdc Giang". 1.2. Muc dich, yeu cau cua de tai 1.2.1. Muc dich: - Giiip ndng dan biet sir dung thudc trir cd trong trdng bdng xen dau xanh. - Tren ca sd nghien cuu sir dung thudc trir cd hgp ly trong rudng trdng bdng xen dau xanh, gdp phan nang cao hieu qua kinh te, tang he sd sir dat va md rdng dien tich trdng bdng d Bac Giang. 1.2.2. Yeu cdu: - Xac dinh dugc loai thudc va lugng phun cd hieu qua trir cd cao nhat tren dat trdng bdng tai Bac Giang. - Tun hieu loai thudc va each sir dimg thudc trir cd hgp ly trong rudng bdng X r f trdng xen dau xanh cho hieu qua kinh te cao nhat. - De xuat quy trinh ky thuat sir dung thudc trir cd hgp ly trong rudng bdng trdng xen dau xanh tmh Bac Giang. Cong ty co phan Bong Mien Bac Pham Van Phu Nghien ct^u anh hu'dng cua bien phap sif dung thuoc tritco den hieu qua cua viec trong bong xen dau xanh tai Bac Giang Phan 2 - TONG QUAN TAI LIEU 2.1. Mot so nghien cuu ve anh huong ciia dieu kien khi hau, dat dai den cay bong "Nhiet do: Nghien cuu ciia Reddy V,R, va ctv (1989)[33] ve anh hudng cua nhiet do ngay/dem den sinh trudng, phat trien va quang hgp cua cay bdng cho thay: nhiet do ngay/dem thich hgp nhat cho sir sinh trudng va phat trien cua cay bdng la 30/20*^0, chenh lech nhiet do ngay dem cang ldn thi qua bdng chin cang nd thoat, nhiet do ban ngay thich hgp nhat cho cay bdng la 30-35 C. Bdng la cay ua ndng, nhiet do la yeu td khi hau anh hudng ldn tdi sinh trudng, phat trien va nang suat cay bdng (Le Song Du, 1996) [5]. •7 * Bp am, luang mua: Cay bdng chiu ban khd tdt nhd cd bd re phat trien va an sau vao Idng dat, nguge lai cay bdng khdng chiu bi iing nudc. De sinh trudng va phat trien binh thudng, cho nang suat va pham chat tdt cay bdng can phai cd che do nudc thich hgp d timg thdi ky sinh trudng khac nhau (mdt sd dac diem sinh ly cay bdng)[18]. Do am khdng khi la mdt trong nhimg dac trung quan trgng nhat cua thdi tiet, nd quyet dinh bdi lugng mua, lam suy yeu buc xa mat trdi. Do am khdng khi anh hudng den ddi sdng cay bdng, do nd anh hudng tdi cudng do thoat hai nude, sue sdng hat phan, sir lan truyen hat phan va sau benh. Vi vay, cay bdng X 1 r f •> phai dugc trdng d nhirng viing it mua va do am khdng khi thap. Neu do am cao se sinh nhieu sau benh, dai hoa rung nhieu, nhat la tir liic ra hoa cho tdi khi qua bat diu chin (Trin Due Hanh va ctv I997)[8]. Tac gia Guinn G, (1982)[27] cho biet: trdi nhieu may kem theo mua rai len hoa dang nd dan den thu phan kem, sd noan thu tinh se bi giam d nhiing qua 3 Cong ty co phan Bong Mien Bac Pham Van Phu Nghien cu'u anh hu'dng cua bien phap su'dung thuoc trifco den hieu qua cua viec trong bong xen dau xanh tai Bac Giang non, day la nai san xuat ra cac hodc mdn can thiet cho sir sinh trudng tiep theo ciia qua, do dd gay nen hien tugng rung dai. Dieu kien khi hau bat thuan nhu nhiet do qua cao hoac qua thap, chenh lech ngay/dem khdng phii hgp hay trdi cd mua, anh sang kem trong thdi ky ra hoa ket qua lam cay sinh trudng kem, hien tugng rung nu, rung dai, rung qua tang, lam giam nang suat. Theo Tdn Thit Trinh (I974)[20] va Hoang Due Phuang (I983)[I6], mua ldn cd the lam bat thu 20-25% sd hoa cua cay bdng, hoac lam cho mdt sd ldn tieu noan cua hoa khdng dugc thu. Neu phan ldn tieu noan khdng dugc thu tinh thi qua non se rung trong khoang 10 ngay sau khi hoa nd. Nang ban ciing lam cho tieu noan dd thu tinh rdi nhung khdng phat trien dugc va ciing lam qua non rung, * Anh sdng: Cay bdng ua anh sang manh. Tir cudi the ky XIX, cac nha sinh ly thirc vat My dd ggi cay bdng la "con de cua mat trdi". Trdng bdng nai anh sang day du se dat nang suat cao, pham chat tdt (Le Song Du, 1996)[5]. * Bat dai: Bdng vai sinh trudng tdt tren nhirng dat cd nhieu mau, cd cau tugng vien ben vCirng, thoat nudc tdt, cd tang canh tac day vi cay bdng cd bd re kha phat trien an sau vao trong dat (sinh ly cay bdng)[18]. Theo Nguyen Khac Trung (I962)[I9], dat bi iing nudc gay nen thieu khdng khi (thieu oxi), boat ddng hd hap cua re bi ngimg tre. Khi dd, re khdng hiit dugc nudc va cac chat dinh dudng de nudi cay, gay nen hien tugng rung nu, rung dai va chet cay. Cay bdng rat man cam vdi dat chua va ham lugng nhdm di ddng trong dat. Nghien cuu cua Doan vien trg Phap d Mien Nam - Viet Nam cho thiy, cac loai dat cd pH < 5,2 khdng trdng dugc bdng, pH tu 5,2 - 5,8 trdng dugc nhung 4 Cong ty co phan Bong Mien Bac Pham Van Phu Nghien cu'u anh hu'dng cua bien phap su'dung thudc trifco den hieu qua cua viec trong bong xen dau xanh tai Bac Giang nang suat thap va bdng mgc tdt khi pH > 5,8. Trudng hgp pH < 5,5 ham lugng ^^^ cao lam cho cay cd the bi ngd ddc (dan theo Vii Cdng Hau, 1978)[I I]. r f y. Quy dat san xuat ndng nghiep ciia cac viing nghien cuu cdn kha ddi dao, trong dd cd khoang 35 - 40% dat ndng nghiep cd the trdng dugc cay bdng lai, Dat dang trdng bdng d cac viing nghien cuu deu cd PHKCI hai chua, ham lugng cac chat tdng sd tir trung binh den ngheo, trong dd ham lugng K2O de tieu d Yen Chau la cao nhat. Dat trdng bdng d Yen Chau cd do tai xdp nhat so vdi cac viing cdn lai. Ham lugng N va P2O5 de tieu d cac viing tuang duang nhau va X t r r \ deu d miic ngheo (Bao cao tdng ket san xuat d cac vimg trdng bdng nam 2006) [1]. Theo kit luan cua Phdng KH«&CN Cdng ty CP Bdng Miln BIC (2006) d tat ca cac viing trdng bdng d Tay Bac, trong dieu kien trdng bdng dai tra tren dat ddi ddc khuyen cao ndng dan ap dung phuang phap lam dat tdi thieu, bdn theo hdc, bdn xong lap dat ngay va bam nggn khi cay bdng dat 12 - 14 canh r f qua/cay. Vung Phu Yen, Bac Yen va Yen Chau nen ap dung diing thudc trir cd trudc khi gieo bdng ket hgp lam cd bd sung 1 lan vao giai doan 40-50 ngay saugieo[l]. 2.2. Mot so nghien ciru ve anh huong cua thoi vu den cay bong Thdi vu gieo trdng cd tinh chat quyet dinh tdi nang suat cay bdng. Viec xac dinh thdi vu gieo bdng thich hgp ciing la mdt van de phuc tap, chiu sir chi phdi cua hang loat cac yeu td nhu dieu kien khi hau thdi tiet, dac tinh gidng, tap quan canh tac, quy luat phat smh phat trien cac loai sau benh hai trong nam Tuy nhien, vdi nhirng vimg khdng tudi, viec trdng bdng hoan toan dua vao nudc trdi thi yeu to chinh quyet dinh thdi vu la lugng mua va sir phan bd mua trong nam. Nghien cuu gan day nhat cua Cdng ty Cd phan Bdng Mien Bac (2005)[10] cho thay, thdi vu trdng bdng tai cac tinh phia BIC ndi chung dao 5 Cong ty co phan Bong Mien Bac Pham Van Phu Nghien cu'u anh hifdng cua bien phap su'dung thudc trifco den hieu qua cua viec trong bong xen dau xanh tai Bac Giang dgng trong khoang tir 5/5 den 5/6, rieng viing niii Tay Bac nen gieo bdng tir 5/5 din 25/5. 2.3. Nhirng nghien cmi ve anh huong ciia mat do gieo trong tren cay bong Trdng vdi mat do hgp ly la mgt bien phap ky thuat quan trgng vdi cay bdng, Vdi mat do tdi thich se cho sd qua/dan vi dien tich ldn nhat, do dd nang suat se dat cao nhat. Mat do gieo trdng la mdt bien phap ky thuat cd y nghia rat r r r ldn tdi nang suat, nhat la khi tien bd ky thuat mdi cua nganh bdng cho phep tang mat do ket hgp vdi viec tang lugng phan bdn, phun PIX, che do luan xen canh ngay cang da dang va cac bien phap canh tac hgp ly la ca sd quan trgng day nang suat bdng len cao. Tai Dien Bien, bien phap gieo trdng vdi mat do hgp ly dugc ap dung d hau r •\ y t f het cac viing trdng bdng, mat do gieo trdng phd bien tai Dien Bien dao ddng tir 4,2 - 5,5 van cay/ha nhu d Tuan Giao 4,2 van cay/ha, cdn d Dien Bien Ddng phd bien tir 4,7 - 5,1 van cay/ha (Nghien ciru dieu tra khdo sdt cua Phdng KH&CN Cong ty CP Bong Mien Bdc ndm 2006){\\ Tuy nhien, viec tang mat do gieo trdng ngoai thuc te rat ban che do muc do dau tu tham canh cua ndng ddn cdn chua tuang xiing vdi viec tang mat do, nhat la khi gieo trdng vdi mat do cao ban niia. 2.4. Mot so ket qua nghien cuu ve anh huong cua phan bon den cay bong Tai vimg niii San La, theo tac gia Dd Khac Ngir (2002) lugng phan bdn cho gidng bdng Iai VN20 d mirc 120 kg N + 60 kg P2O5 + 60 kg K2O (ty le 2:1:1) cho nang suat bdng hat va hieu qua khih te cao nhat [15]. Tuy nhien viec bdn phan d timg vung cdn phu thudc chat dat, va dieu kien canh tac cua ndng hg. Theo bao cao ket qua nghien cuu khoa hgc nam 1999 cua Trung tam nghien ciru cay bdng Nha Hd: phan bdn cd anh hudng kha rd den sd qua/cay 6 Cong ty co phan Bong Mien Bac Pham Van Phu [...]... qua cua viec trong bong xen dau xanh tai Bac Giang van de nay da giiip de tranh nang suat thap trong nhiing mua vu khac nhau Mgt anh hudng tuang tu cd the xay ra, neu trdng xen giam dich hai, nhu vay trdng xen da chi ra do dn dinh ldn ban va bieu hien tdt nhat d dieu kien khd khan Theo Shar Ma S, K, Miehta (1988) [30] khi nghien ciiu trdng xen d An r y y f f Do da ket luan: Trdng xen da lam giam cac chi... giam dugc sdi mdn ciia dat r \ y X X Dac biet trong nhirng nam gan day cd rat nhieu nghien ciiu ve trdng xen cay bdng vdi cay trdng ndng nghiep khac nhu: Trdng bdng xen ngd, bdng xen vai, bdng xen dau tuong, bdng xen cai bap Nhung nhin chung cdn it dac biet la nghien ciiu ve trdng bdng xen dau xanh X ^ X X Bdng la cay hiit nhieu chat dinh dudng va la cay trdng bj nhieu loai sau 9 Cong ty co phan Bong... cay dau xanh 17 Cong ty co phan Bong Mien Bac Pham Van Phu Nghien cu'u anh hu'dng cua bien phap su'dung thuoc trifco den hieu qua cua viec trong bdng xen dau xanh tai Bac Giang • Phun sau gieo 65 ngay vdi lugng nudc 360 lit/ha (phun 3 binh/IOOO m^, moi binh 12 lit), dimg chyp vdi phun dinh hudng theo hang khdng de thudc tilp xiic vdi cay bdng va cay dau xanh '^' *^' + Ky thudt trong bong xen ddu xanh. .. nhau tren ruong bong trong xen dau xanh tai Bac Giang 29 Cong ty cophan Bong Mien Bac Pham Van Phu Nghien cu'u anh hu'dng cua bien phap sif dung thuoc tru'cd den hieu qua cua viec trong bdng xen dau xanh tai Bac Giang 4.4.1 Anh hu&ng ciia so ldn phun thuoc trir co Ka nup 480 SL, Glyphosan 480 BB, Giy up 480 SL den ty le ndy mam vd sinh tru&ng, phdt trien cua cdy bong trong xen Nghien ciiu, theo ddi... viec trong bong xen dau xanh tai Bac Giang Theo Dinh Quang Tuyen va CS 2006 [23] khi nghien ciiu bien phap ky thuat canh tac cho bdng trdng tham canh da dua ra ket luan: Cac md hinh trdng y f > r X f xen trdng gdi bdng trong cay trdng 1 vu deu lam giam nang suat bdng so vdi ddi chiing khdng trdng gdi va trdng thuan Trdng xen bdng trong dau tuong theo kieu hang kep giiia khoang each 120 cm xen 3 hang dau... Pham Van Phu Nghien cu'u anh hifdng cua bien phap su'dung thuoc trifco den hieu qua cua viec trong bong xen dau xanh tai Bac Giang - Thi nghiem 3: Ddnh gid hieu qud cua 3 thuoc trir co Kanup 480 SL, Glyphosan 480DD, Giy up 480 SL vdi so ldn phun khdc nhau tren ruong bong trong xen ddu xanh tai Bdc Giang Cdng thiic thi nghiem: Cdng thiic Ten thudc Sd lan phun CTI (D/c): lam cd bang tay - - Ka nup 480... [12] cho rang mat do X ^ X ray xanh hai cham tren md hinh bdng trdng xen vdi dau xanh, dau nanh va ngd cd xu hudng thap hon so vdi mat do ray xanh hai cham d md hinh bdng trdng thuin t! r X O Mai Son - San La tren dat bai bang da ap dung thanh cdng cac md hinh ' X ^ r r xen, gdi cay bdng vdi cac cay trdng ngan ngay Dac biet, ca cau xen canh gdi 10 Cong ty co phan Bong Mien Bac Pham Van Phu Nghien cu'u... Tat ca cac cdng thiic trdng xen da giam so vdi nang suat thuc cua nd Nhu vay khdng chi tren cac cay trdng ma tren ca cay bdng thi van de trdng xen van dugc cac nudc tren the gidi tiep tuc nghien ciiu O Viet Nam, trdng xen cQng dugc nghien ciiu tir rat lau, song den ngay nay thi hieu qua cQng nhu nhimg ket luan ve trdng xen van cdn rat khac nhau va viec nghien ciiu ve trdng xen tren tat ca cac loai cay... den hieu qua cua viec trong bdng xen dau xanh tai Bac Giang - Thl nghiem 1: Dieu tra thdnh phdn cd dgi tren rupng bong trong a Bdc Giang r y t nt, X + Tien hanh dieu tra ngau nhien tai 5 diem ciia vung trdng bdng - Thi nghiem 2: Ddnh gid hieu luc ciia 3 thuoc trir co Kanup 480 SL, Glyphosan 480DD, Giy up 480 SL vai cdc lugmg sir dung khdc nhau tren ddt trong bong tgi Bdc Giang t r f + Dia diem: Thi nghiem... Theo Duang Hdng Hien 1962 [9]: Trdng xen d tren ddi cd tac dung ldn trong viec giii dat, giir nudc va giii am do dat do xen canh tao ra cac tham xanh che phu dat nen cd tac dung bao ve dat, chdng xdi mdn va dieu hoa che do nudc trong dat, d nhimg nai dieu kien dat va lugng mua che ngu nhimg he thdng trdng xen cd the cho nang suat va dn dinh cao Khi nghien ciiu ve trdng xen va gdi, Tran Van Lai 1996 [13] . trdng xen cay bdng vdi cay trdng ndng nghiep khac nhu: Trdng bdng xen ngd, bdng xen vai, bdng xen dau tuong, bdng xen cai bap. Nhung nhin chung cdn it dac biet la nghien ciiu ve trdng bdng xen. viec trong bong xen do xanh tai Bdc Giang& quot;. 1.2. Muc dich, yeu cau cua de tai 1.2.1. Muc dich: - Giiip ndng dan biet sir dung thudc trir cd trong trdng bdng xen dau xanh. - Tren ca. bong xen dau xanh tai Bac Giang van de nay da giiip de tranh nang suat thap trong nhiing mua vu khac nhau. Mgt anh hudng tuang tu cd the xay ra, neu trdng xen giam dich hai, nhu vay trdng xen