PHN I M U 1.1. t vn Ca chua (Lycopersicon esculentum Mill.) thuc ho ca (Solanaceae), c ngun gc Nam M l loi rau qu c ngi tiu dng trn th gii cng nh Vit Nam rt a chung.C Chua l loi qu cung cp vitamin A va C rt quan trong va c s dung rt phong phu, a dang, phu hp vi khu vi cua nhiu ngi va cua nhiu la tui. C chua c th s dng theo nhiu phng thc khc nhau nh: n ti( lm salat, n qu ti, ch bin cc mn n); ch bin( c chua c c, c chua ng hp nguyn qu, nc qu, tng c chua). Nhng t nhng nm 1960, c bit sau ngy gii phng min Nam, vi nhiu ging cy trng mi c p dng trong sn xut, h thng ti tiu c ci to v m rng, din tch ti tiu c tng ln, phn ha hc v thuc tr su c dng vi s lng ln. Vic p dng cc ging cy trng mi vo sn xut cng l nguyn nhn lm mt dn i mt s cc ging cy trng truyn thng, lm gim s a dng sinh hc v lm tng thit hi bi dch hi cy trng. Khi s dng qu nhiu lng phn bn ha hc v cc loi thuc bo v thc vt mang li nh hng xu n mi trng. Theo c tnh th 50% lng phn bn c cy trng s dng, cn 50% lng d phn ha hc b bay hi, ra tri v cng l nguyn nhn gy nhim khng kh, t v nc. Cng vi con ng mt s lng ln thuc bo v thc vt d tha tn ti trong t, nc v gy nhim mi trng. Lng thuc ny s dng khng hp l dn ti s hnh thnh tnh khng thuc ca su hi, nh hng ca d lng thuc bo v thc vt l tc ng xu ti sc khe con ngi, ng vt, v mi trng sng. Nhng hn ch ca cuc cch mng xanh v cng nghip ha nng nghip, dn n nhiu nc quay tr li vi nng nghip hu c (trong c Vit Nam), lm cho

nng nghip hu c ngy cng c nng cao v tr v tm quan trng trong i sng x hi v trn th trng th gii (Ngun TS.L Vn Hng V KHCN, B NN $ PTNT).Tuy nhin canh tc hu c cn l vn mi m i vi vit nam. y l hnh thc sn xut nng nghip s dng cc bin php canh tc v chn nui t nhin, khng s dng ha cht lm phn bn v thuc tr su, cc cht kch thch tng trng v cc ch phm bin i gien.Sn xut nng nghip hu c s mang li nhiu li ch nh duy tr v bo v ph nhiu ca t; t gy nhim ngun nc; bo v mi trng sinh thi; bo v i sng hoang d ca cc loi chim, ch, nhi, cn trng...; tnh a dng sinh hc cao; t s dng nng lng v u vo khng c kh nng phc hi t bn ngoi; t d lng thuc tr su trong thc phm; khng c cht khng sinh v hocmn trong cc sn phm ng vt; cht lng sn phm tt hn, sch hn, an ton hn. Sn phm nng nghip hu c c cht lng cao v m bo an ton cho sc khe con ngi.Trn th trng Vit Nam, ngi tiu dng bit n v ang lm quen dn vi cc sn phm nng sn sch nh: rau sch, rau an ton v mt s hoa qu, thc phm an ton. Nhng sn phm ny ngy cng khng nh c vai tr trong i sng ca nhn dn. C th ni, vi nhng i hi ngy cng cao ca th trng tiu dng, nng nghip hu c s l xu hng tt yu trong thi gian ti (Ngun bo NGHEANDOST KHOA HC CNG NGH). Xut pht t yu cu thc tin chng ti tin hnh ti :"So snh mt s ging c chua trong iu kin canh tc hu c v Thu ng 2011 ti Gia Lm, H Ni"

1.2. Muc ich va yu cu 1.2.1. Muc ich cua tai nh gi s sinh trng, pht trin, nng sut, cht lng v kh nng chng chu su bnh ca mt s ging c chua trng trong iu kin canh tc hu c v Thu

ng 2011 ti Gia Lm, H Ni. T tm ra ging c chua thch hp trong iu kin canh tac hu c hng ti xy dng nn nng nghip bn vng 1.2.2. Yu cu cua tai - nh gi tnh hnh sinh trng, pht trin ca cc ging c chua trong iu kin canh tc hu c. - nh gi tnh hnh su bnh hi cc ging c chua trong iu kin canh tc hu c. - anh gia cac yu t cu thanh nng sut va nng sut cua c chua trong iu kin canh tc hu c. - anh gia c im hinh thai, cu truc qua va cht lng qua ca cc ging c chua trong iu kin canh tc hu c.

PHN II TNG QUAN TI LIU 2.1.Ngun gc, phn loi v gi tr ca cy c chua 2.1.1. Ngun gc, phn b ca cy c chua C chua trng hin nay c ngun gc pht sinh t vng Pru, Ecurado v Bolivia dc b bin Thi Bnh Dng t qun o Galanpagos ti Chile, l cc nc Nam M thuc khu vc nhit i kh (De Candole, 1984;Choudhyru.B, 1970). Tuy nhin nhiu tc gi khc nhn nh L.esculetum var cerasiforme (C Chua anh o) l t tin ca C Chua trng. Theo cc nghin cu ca Jenkins(1948), cho rng c th dng ny c chuyn t Peru v Equado ti nam Mehico, n c dn bn x thun ha v ci to.Mt s tc gi cho rng, pha ty dy ni Andes l t tin th 2 ca loi C Chua trng Lycopesicon esculentum c Miller t tn. Nhiu bng chng kho c hc, thc vt hc tha nhn Mehico l trung tm thun ha C Chua(Jenkin, 1948). Theo Luckwill(1943), C Chua xut hin Chu u vo th k XVI-XVII v c trng u tin Ty Ban Nha, B Nha v Italia do cc nh bun cc nc nay chuyn t Nam M ti.T cy C Chua c lan truyn i ni khc, trong thi k ny C Chua ch c xem nh cy cnh v cy thuc. n th k XVIII, cy C Chua mi c chp nhn l cy thc phm c gi tr v t pht trin mnh( dn theo ti liu Kuo- v cng s, 1998). Nhiu ti liu ghi nhn, C Chua xut hin Bc M vo nm 1710, giai on ny ngi ta quan nim C Chua l cy c hi n sc khe nn cha c chp nhn.n nm 1830, C Chua mi c chp nhn l cy thc phm (Hei ser, 1969). Theo Luck Will (1943); Kuo et al v Cs, 1998, th qu trnh du nhp ca c chua vo cc nc Chu c bt u t Philipin, o Java v Malayxia, thng qua cc thng nhn v thc dn H Lan, B o Nha, Ty Ban Nha vo khong th k

XVII. Sau c trng ph bin ra cc vng ln cn. Cui th ky XIX u th ky XX, cy ca chua mi du nhp vao Vit Nam va t o tr thanh mon n quen thuc cua nhn dn ta. Trong nhng nm gn y nc ta, din tich trng ca chua ngay mt tng. iu kin thin nhin, khi hu va t ai nc ta rt thich hp cho ca chua sinh trng va phat trin. 2.1.2. Phn loi cy c chua. C chua (Lycopersicon esculentum.mill) thuc h C (Solanceae) chi Lycopersicon. C b NST 2n = 24 gm c 12 loi. Theo H.J. Muller (1940) th loi c chua trng trt hin nay thuc chi ph Eulycopersicon C.H. Muller. Theo cch phn loi ca Brezhnev (1964), chi Lycopersicon Tourn c phn lm 3 loi thuc 2 chi ph hai chi ph: Subgenus 1: Eriopersicon Subgenus 2: Eulycopersicon - Chi phu: Eriopersicon: Dang cy mt nm hoc nhiu nm, qua khng bao gi chin o, lun lun co mau xanh, co soc tia, qua co lng, hat nho. Chi nay gm 5 loai hoang dai, thuc hai loai: L.hirsutum va L.peruvianum. - Chi phu: Eulycopersicon: La dang cy hang nm, qua chin o hoc vang, gm co 1 loai: L. esculentum Mill. Loai nay gm 3 loai phu: 1. L. esculentum Mill.ssp.spontaneum (Ca chua dai) 2. L. esculentum Mill.ssp.subspontaneum (Ca chua ban hoang dai) 3. L. esculentum Mill.ssp.cultum (Ca chua trng) l loi ln nht, c cc bin chng c kh nng thch ng rng, c trng rng khp th gii. Breznep chia loi ny thnh 3 dng sau: * L.Esculentum var. Grandiflium (Bailey) Brezh: C chua l to, cy trung bnh, mt l lng bng, s l trn cy t t n trung bnh. * L.Esculentum var. Validum (Bailey) Brezh: Thn bi, cy thp, thn c lng

t, l trung bnh, cung ngn, mp cong. * L.Esculentum var. Vulgare Brezh. (Trch theo Nguyn Hng Minh, 2000) 2.1.3. Gi tr ca cy c chua. 2.1.3.1.Gi tr dinh dng. C chua l loi rau n qu c gi tr dinh dng cao, trong qu chn c nhiu ng, ch yu l ng glucoza, c nhiu vitamin: Caroten, B1, B2, C; axit amin v cc cht khong quan trng: Ca, P, Fe v.v(theo T Th Cc, 2007). Theo E.D Warr C.Tigchelaar(1989) thnh phn ha hc ch yu ca c chua nh sau:Nc: 94 95%, cn li l cc cht kh chim: 5 6%, trong cht kh gm 55% ng(Glucoza, Fuctoza, Sucroza); 21% cht khng ha tan trong ru(Protein, Pectin, Polysaccarit, Xenlulo); 12% axit hu c( citric, malic, galaturonic, pyrrlidoncacboxylic); 7% cht v c; 5% cht khc(Carotenoit, Ascorbic,Cht d bay hi). Theo V Vn Chi (1997) v L Trn c (1997), qu c chua c v ngt, tnh mt, c tc dng to nng lng, tng sc sng, lm cn bng t bo, gii nhit, chng hoi huyt, khng khun. Theo T Th Cc(1985), kt qu phn tch trn 100 mu ging vng ng bng sng Hng c thnh phn ha hc ch yu nh sau: Cht kh: 4,3 6,4% ng tng s: 2,6 3,5% Axit tng s: 0,22 0,72 Brix khong 2,6 - 3,5%

Hm lng Vitamin C: 17,1 38,81 mg. Beker- Billing so snh thnh phn dinh dng ca C Chua vi 1 s loi qu khc nh: To, Anh o ,Du ty cho thy vitamin C c trong C Chua cao gp 10 ln trong du ty v 2 ln so vi anh o.Ngoi ra, C Chua cn c gi tr ln v mt y hc nh: tht qu gip tiu ha tt, nhun trng, thuc y vic tit dch ca d dy v

lc mu, kh trng ng rut, lot v au ming.Nc p C Chua kch thch gan, gi cho d dy v rut trong iu kin tt(L Trn c, 1997). Theo Tt Li,( 1999), l non gi nh p ln mn nhn ngy 2 ln th s ht mn. Cht Totamin, chit xut t l C Chua co tc dng khng khun, chng nm, dit 1 s bnh hi cy trng. 2.1.3.2. Gi tr kinh t. T gia tri dinh dng va gia tri y hoc lam cho ca chua la loai rau cho hiu qua kinh t cao, l mt thnh phn khng th thiu c trong i sng con ngi. C chua va cho sn phm n ti, nu nng va l nguyn liu cho ch bin cng nghip vi nhiu loi sn phm khc nhau. Theo FAO (1999) ai Loan hang nm xut khu ca chua ti vi tng gia tri la 952.000 USD va 40.800 USD ca chua ch bin. Lng C Chua trao i trn th trng th gii 1999 l 36,7 tn ,trong C Chua c dng dng n ch 5 7%. Theo T Thu Cc(2004), M (1997), tng gi tr sn xut 1ha c chua cao hn gp 4 ln so vi trng la nc, 20 ln so vi trng la m . Vit Nam, c chua c trng khong trn 100 nm nay, din tch trng hng nm bin ng t 12 13 nghn ha. Theo s liu phng kinh t th trng( Vin Nghin Cu Rau Qu) sn xut C Chua ng Bng Sng Hng cho thu hoch bnh qun 42,0 - 68,4 triu /ha/v vi mc li thun 15 26 triu ng/ha cao gp nhiu ln so vi trng la. Theo o Xun Thng (2005) ging c chua Lai s 1, C95 c sn xut th ti Nam nh cho thu nhp 35 40 triu ng/ha, li thun 15 20 triu ng. 2.2. Cc yu t nh hng n sinh trng v pht trin ca cy c chua. 2.2.1. Nhit . C chua c ngun gc vng ni nhit i kh, thuc nhm cy a nhit n ha. Nhit nh hng sut qu trnh sinh trng v pht trin ca cy c chua: t ny mm, tng trng cy, n hoa, u qu, hnh thnh ht v nng sut thng

phm. Ht c chua c th bt u ny mm nhit 15 18oC nhng ny mm nhanh nhit 25 - 30 oC, ngoi ngng ny t l ny mm gim hoc ny mm chm. C chua sinh trng v pht trin thun li nhit 20 - 27 oC. Trn 30 oC kt hp vi hn t, hn khng kh s dn n ri lon trong qu trnh ng ha lm nng sut gim nghim trng. Nhit cao trn 35 oC th c chua ngng sinh trng. Nhit thch hp cho s n hoa ca c chua khong 20 - 25 oC. Sau gieo 15 22 ngy nu iu khin c nhit ban m xung ti 10 - 13 oC th c chua ra hoa sm hn v tng s hoa/chm (Lewis, 1953; Wittwer v Teubner, 1956). Nhit thch hp cho u qu: ban m 15 - 20 oC v ban ngy khong 25 oC. Nhit cn nh hng n qu trnh chn ca qu. C th nhit v nh sng nh hng n mu sc chn ca qu. Licopen l sc t mu , c hnh thnh trong iu kin nhit khong 20 oC do vy ma h c chua thng c mu vng. Nhit tt nht cho qu chin l 22 oC, ban m trn 13 oC, ban ngy 24 - 30o

C. Hin nay cc nh chn ging chn to ra c nhiu ging c kh nng chu

nng nn c th trng c chua quanh nm v khong nhit thch hp cho c chua sinh trng v pht trin cng rng ra. 2.2.2. nh sng. C chua l cy a nh sng mnh nhng li khng phi l cy phn ng vi nh sng, do nc ta c chua c th trng c quanh nm. C chua a cng nh sng mnh, nu thiu nh sng th cy s sinh trng yu, thi gian sinh trng ko di v sn lng thp. thi k cy con, nu thiu nh sng cy s vn cao, lng di s b . Cng nh sng ti thp cho sinh trng v pht trin ca cy c chua l 4000 lux . Cng nh sng thch hp nht cho c chua l 14000 20000 lux . 2.2.3. Nc v m . C chua l cy tng i chu hn, nhng yu cu v nc nhiu v khi lng thn

l trn mt t tng i ln. Somos (1971) quan st thy s tiu hao nc ca c chua trong mt ngy m l 20 650g, s khc nhau qu xa c lin quan n s pht trin ca cy v iu kin thi tit. Theo tnh ton ca cc nh khoa hc th t nng sut 50 tn/ha cn ti 6000m3 nc (Mai Thi Phng Anh, 2003). ht c chua cn lng nc t 325 364% so vi khi lng bn thn ny mm (Tsachenko, 1967). m thch hp cho cy sinh trng v pht trin l 70 80%. Thi k khng hong nc l t khi hnh thnh phn hoa, ra hoa, hnh thnh qu v qu pht trin. nhng thi k ny cy c nhu cu ln i vi nc nhng nu d tha nc cng nh hng khng tt n sinh trng v pht trin. Nu m khng kh cao (95%) lm cho cy sinh trng rt mnh, l mm, mng, cy yu, gim kh nng chng chu su bnh v iu kin ngoi cnh. 2.2.4. t v dinh dng C chua a trng trn t thot nc kh vi chua trung tnh, pH = 6,0 7,0. Cy c chua mn cm vi phn hu c v phn khong, s dng phn bn thch hp s nng cao sn lng v cht lng qu. C chua yu cu ch lun canh nghim ngt, khng c trng c chua trn loi t m cy trng v trc l nhng cy thuc h c: Khoai ty, c pho, c tm,.V dinh dng cy c chua cn t nht 12 nguyn t l pht pho (P), kali (K), lu hunh (S), magie (Mg), Bo (B), st (Fe), mangan (Mn), ng (Cu), km (Zn), molipden (Mo) v canxi (Ca). Trong c chua s dng nhiu nht l kali (K), m (N), sau mi n ln (P) v canxi (Ca). Ty tng loi t vi ph khc nhau m ta c mc phn bn khc nhau. T l bn cc nguyn t dinh dng ch yu ph thuc vo tui cy, ging v iu kin trng. C chua s dng 60% N, 50 60% K2O v 15 20% P2O5 tng lng bn vo t trong sut v trng. Theo More (1978) c 1 tn c chua cn 2,9 kg N, 0,4 kg P2O5, 0,4 kg K2O v 0,45 kg Mg. Cn theo Becseev, to 1 tn c chua cn 3,8 kg N, 0,6 kg P2O5 v 7,9 kg K2O (trch dn theo Kiu Th Th, 1998). Nhu cu v dinh dng ca c chua c th nh sau:

- V m: C chua yu cu nhiu m nhiu vo thi k ra hoa v kt qu. m l nguyn t dinh dng quan trng duy tr s sinh trng, hnh thnh cc b phn dinh dng ca cy. - V ln: Pht pho l mt trong nhng thnh phn ch yu ca t bo v m cy. N xc tin qu ln nhanh trong iu kin cung cp m y . Cy c bn ln y s n hoa v chn sm hn, cht lng qu cng s tt hn. Thiu ln, cy ng ha km, do vy khi thiu ln s ko theo thiu m v mt s cht khong khc. - V kali: Kali cn thit cho qu trnh ng ha CO2 to thnh gluxit, ng thi hn ch c s pht trin ca bnh hi. Kali cn gip cho cc t bo cng cp hn, lm tng kh nng ct gi v vn chuyn, c vai tr quan trng trong vic hnh thnh mu sc, tng lng caroten v gim lng clorophin. c th p ng y v ng lc cho cy c chua chng ta cn phi hiu r v nhu cu dinh dng ca cy v kh nng cung cp dinh dng ca t nh trng c chua. C nh vy th nng sut c chua mi cao v c n nh. 2.3.Tnh hnh sn xut v nghin cu c chua trong nc v trn th gii. 2.3.1. Tnh hnh sn xut v nghin cu c chua trn th gii. 2.3.1.1 Tnh hnh sn xut c chua trn th gii Hin nay c chua l mt loi rau c s dng rng ri trn khp th gii trong cc ba n, trong thm m v trong cng nghip ch bin. Chnh v th m din tch trng c chua lun lun tng trong cc nm trc v gn y. Tnh t nm 1990 n 2002 din tch trng c chua trn th gii tng t 2.868.443ha ln n 3.745.229ha v sn lng t 76.022.112 tn tng ln 100.259.346 tn/nm, nng sut t 27,005 tn/ha. Din tch trng c chua th gii nm 2005 t 4.570.869 ha tng gp 1,4 ln so vi nm 1995. Trong , din tch trng c chua hu ht cc khu vc trn th gii c xu hng tng, ring khu vc Bc M v mt s nc chu u c din tch c

chua gim. Din tch c chua chu tng trn 200%, trong Trung Quc c din tch trng c chua ln nht, t 1.305.053 ha (2005), tng 175% so vi nm 1995; din tch trng c chua n tng 54% trong 10 nm t 1995 2005. Bng 2.1. Tnh hnh sn xut c chua trn th gii tch(nghn ha) 1995 3.272,021 26,770 1997 3.566,252 25,044 1998 3.566,252 26,453 1999 3.763,183 27,734 2000 3.750,176 27,192 2001 3.745,229 26,770 2002 3.998,219 27,005 2003 4.188,389 27,921 2005 4.570,869 27,222 (Ngun FAO Database Static 2006) Nm Din Nng sut(tn/ha) Sn lng(nghn tn) 87.592,093 89.313,832 94.338,747 104.366,671 101.975,637 100.259,346 107.972,098 116.943,619 124.426,995

Mc d nng sut c chua th gii khng tng nhng do din tch c chua tng nn sn lng c chua cng tng kh cao (tng 42% t nm 1995 n 2005), trong Trung Quc l nc c sn lng c chua tng cao nht (140%), Iran (tng 74%), Ty Ban Nha (63%). mt s khu vc din tch trng c chua khng tng nn sn lng cng khng tng thm ch cn gim, nh M (sn lng gim,2%), Hy Lp (gim 17%). Trn th gii c chua c trng quanh nm, mc d c chua l cy trng c xem l mn cm vi sng gi nhng n vn c trng thnh cng trong iu kin che chn sut t Equador cho n tn vng cc Bc nh: Alaska. Hin nay trn th gii vic sn xut c chua c chuyn mn ha cao, cc nc c nn cng nghip tin tin p dng vic thu hoch c chua bng my. C chua sn xut chu M, chu u thng c ch bin thnh cc dng sn phm khc nhau nh c chua ng hp, c chua c c,. Xut khu c chua c c chu u chim ti 56% lng xut khu ton th gii (nm 1999). Gn y, Trung Quc y mnh vic p dng

khoa hc k thut tin tin trong vic sn xut v ch bin c chua phn u tr thnh nc xut khu c chua ln nht th gii. Bng 2.2: Sn lng c chua ca th gii v 10 nc dn u th gii trong 4 nm. Quc gia Th gii Trung Quc M Th Nh K n Italy Ai Cp Ty Ban 1995 87.592,093 13.172,494 11.784,000 7.250,000 5.260,000 5.182,000 5.034,179 2000 108.339,598 22.324,767 11.558,800 8.890,000 7.430,000 7.538,100 6.785,640 2003 116.943,619 28.842,743 10.522,000 9.820,000 7.600,000 6.651,505 7.140,198 3.947,327 3.708,600 4.200,000 2.148,130 1.830,000 2005 124.426,995 31.644,040 11.043,300 9.700,000 7.600,000 7.087,016 7.600,000 4.651,000 3.396,767 4.200,000 2.800,115 1.713,580

2.841,100 3.766,328 Nha Braxin 2.715,016 2.982,840 Iran 2.403,367 3.190,999 Mehico 2.309,968 2.086,030 Hy Lp 2.064,160 2.085,000 (Ngun FAO Database static 2006)

2.3.1.2 Tnh hnh nghin cu c chua trn th gii Chn ging c chua bt u tin hnh t th k XIX. Khi u vi s chn to c in (dng cc phng php lai v chn lc ). Sau vi s tin b ca khoa hc k thut, s xut hin ca cc hc thuyt v s xut hin ca di truyn hc to nn tng cho cc nh chn ging tm ra nhng phng php mi p dng vo chn to ging v chn ging c chua cng pht trin theo . Hin nay, cc nh chn ging trn th gii t ra nhiu mc tiu chn to ging khc nhau phc v mc ch ca con ngi: chn ging c chua phc v ch bin, ging c chua chu nhit trng tri v, ging c chua chng chu su bnh, chng chu iu kin ngoi cnh bt li M tin hnh cng tc chn ging c chua t rt sm v thu c nhiu thnh tu ng k. Chng trnh th nghim ca Liberty, Hyde Bailey ti trng Nng nghip Michigan (M) bt u t nm 1886, tc gi tin hnh chn lc, phn loi ging c chua trng trt. Trng i hc California chn c nhng ging c chua mi nh: UC-105, UC-82, UC-134 c nng sut cao hn hn VE-145 v c nhiu c im tt nh: qu cng, tnh chu nt qu cao. (dn theo ti liu ca H Hu An, 1996). Nhiu cng trnh nghin cu ca Trung tm nghin cu v pht trin Rau chu (AVRDC) cho thy, nhng ging c chua c chn to trong iu kin n i khng thch hp vi iu kin nng m v s to ra nhng qu km cht lng nh c mu nht, nt qu, v nht hoc chua (Kuo v cs, 1998). Do vy, ngoi mc tiu chn ging c nng sut cao, cht lng tt th chn ging c chua thch hp iu kin nng m cng cn c quan tm. chn c nhng ging tt c nng sut cao, cht lng tt, chng chu su bnh th nhiu nh khoa hc s dng ngun gen di truyn ca cc loi hoang di v bn hoang di, v chng c kh nng chng chu tt vi iu kin mi trng bt thun v p dng nhiu phng php khc nhau nh: lai to, chn lc giao t, di nn nhit cao v thp, chn lc hp t (phi

non), gy t bin nhn to,chn to ra cc ging c th trng nhit cao, chng chu su bnh, trng c nhiu v trong nm. Giai on 1987 1988, ti Trung tm nghin cu v pht trin Rau chu (AVRDC) i Loan kho nghim, nh gi v xc nh c cc ging c chua ch bin c trin vng, chn tp trung, chc qu, cho nng sut cao nh: PT4121 (114 tn/ha), PT41729 (104 tn/ha) v ging PT4024 (115 tn/ha) (AVRDC, 1990). Trung tm nghin cu v pht trin Rau chu (AVRDC) cn pht trin chng trnh v cc dng t phi hu hn v v hn c kh nng cho u qu gii hn nhit cc i 32 34oC v cc tiu 22 - 24 oC v a ra nhiu ging trin vng cho cc nc nhit i nh: CLN 161L,CLN 2001C, CL5915-204DH, (Morris, 1998). Cc nh khoa hc AVRDC phn lp c dng c chua khng geminivirus mang alen TY-2, alen ny c ly t ging c chua H24 ca n . H cn pht hin ra trn 25 ging c cha cc gen khng geminivirus, y l ngun vt liu qu to ra cc ging khng virus trong tng lai. Ging CLN2498 l ging khng virus c chuyn gen TY-2, ging ny c cht lng cao, dng bn hu hn, nng sut 50 tn/ha v trng lng 80 90 g/qu . AVRCD cng a ra 2 ging c chua ch bin l Tainan Selection32 v Tainan Selection33 c c im qu trn , chc, chu nhit v chng bnh Fusarium. Theo J.T. Chen v P. Hanson ( thuc AVRCD), khi trng c chua vo ma h, nu thi gian c chua hnh thnh qu ri vo iu kin nhit trn 30oC, nu c th s dng hormone c tn thng mi l Tomatotone hoc Tomatolan, hoc s dng axit 4-chlorophenoxy acetic pha vi nng thch hp ri phun trc tip vo chm hoa c chua ( n 3-5 hoa) sau 3 gi chiu th s lm tng t l u qu , qu to, nng sut cao, tng ng vi khi qu c hnh thnh nhit 15 25oC. Theo cc kt qu iu tra ca trng i hc Kasetrart th tt c cc ging trng ph bin trong sn xut Thi Lan u rt mn cm vi Tomato yellow leaf curl

virus (TYLCV). T h ra mc ch chn to ging c chua c kh nng khng bnh virus xon vng l (TYLCV). Nm 1999 2000, ti trng i hc Kasetrart tin hnh kho nghim 25 ging c chua khng virus t cc a phng khc nhau. Kt qu, ch 1 ging c chua TLCV271/1x26-1 v 2 dng c chua hoang di LA1392 (L. chilense), LA177 (L. hirsutum) khng tt nht vi virus xon vng l (L Th Liu, 2000). Ti Bngladt, hai nh n khoa hc nng nghip l Selina Suntana v Shamoni Shaha trong 6 nm to ra mt loi c chua lai ghp mi tn l Mintoo c th trng gn nh mi iu kin thi tit. Trng lng trung bnh 60 80 g/qu, tng thi gian thu hoch 80 100 ngy v c th bo qun trong thi gian 10 15 ngy . Indonesia, cc nh chn ging tp chung nghin cu cc ging chu nhit v khng bnh ho xanh vi khun (Pseudomonas solanacearum) phc v cho pht trin c chua vng t thp. Nghin cu c tin hnh trn nhng dng c chua nhp ni v con lai gia cc dng, ging vi cc ging a phng. Kt qu cho thy, cc dng nhp ni t AVRCD v cc dng ca trng Louisiana Lembang c nh gi tt nht , trong cc dng, ging c cng nhn l Berlian v Mutiara (Permadi, 1989). Nhm nghin cu ca Martine Verhoeyen, thuc trung tm nghin cu Unilever ti Sharnbrook, Bedfordsshire (Anh) thnh cng khi cy mt gen quy nh vic to ra cht flavonol ca loi hoa d yn tho v cy c chua. Vi gen ny, cy c chua c th sn xut ra lng cht ny gp 78 ln so vi bnh thng. Flavonol l hp cht gip cho c th chng li ung th v tim mch. 2.3.2. Tnh hnh sn xut v nghin cu c chua Vit Nam. 2.3.2.1 Tnh hnh sn xut c chua Vit Nam. C chua l cy trng thch hp vi kh hu mt m, khng thch hp vi nhit cao v ma nhiu. V th nc ta c chua c trng ch yu tp chung vng ng bng sng Hng bao gm cc tnh: Hng Yn, H Ty, Bc Ninh, Hi Dng,

Vnh Phc,chim 60% din tch c nc. Cn min Nam tp chung cc tnh: An Giang, Tin Giang, Lm ng, ... Hin nay, c nc ta c khong 115 ging c chua c gieo trng, trong c 10 ging c gieo trng vi din tch ln 6.259 ha, chim 55% din tch c nc (theo iu tra ca TS Phm ng Qung v cs). Ging c trng nhiu nht nc ta hin nay l M386 vi khong 1.432 ha, sau l ging c chua ca Php, VL200, TN002, Red Crown, Ba Lan, T42, VL2910, Trang Nng,. Bng 2.3 : Din tch, nng sut v sn lng c chua t 2000 n 2005 (nghn ha) 2000 13,729 2001 17,834 2002 18,868 2003 21,628 2004 24,644 2005 23,354 (Tng cc thng k 2006) Nm Din tch Nng sut (t/ha) 151,260 157,170 165,500 164,100 172,400 198,000 Sn lng (nghn tn) 207,658 280,289 312,178 354,846 424,126 462,435

Vi s tin b ca khoa hc k thut, c bit l cng ngh sinh hc, nhiu nh chn ging trong a ra c nhiu ging mi c nng sut cao, cht lng tt, thch hp vi iu kin kh hu nc ta. C chua khng ch c trng vo v ng m nay c v c chua xun h, tri v m vn cho nng sut cao. Tim nng pht trin sn xut c chua nc ta l rt ln, nht l cc tnh pha Bc vi kh hu bn ma r rt. Do chng ta cn u t ging, k thut pht trin thnh nhng vng sn xut chuyn canh cy c chua khng nhng cung cp trong nc m cn phc v cho ch bin xut khu. 2.3.2.2 Tnh hnh nghin cu c chua Vit Nam. Trong nhng nm gn y, vic pht trin c chua c v din tch, nng sut v chng loi tr thnh mt trong nhng mc tiu chnh trong cc n pht trin ca B Nng nghip v pht trin nng thn. Do , trong nhng nm gn y cng

tc chn to ging c chua t c nhiu thnh tu ng k. c th hin qua cc giai oan: + Giai on 1968 1985: Tp trung chinh vo vic nhp ni, kho nghim v tuyn chn ging t ngun vt liu ny. Do Vin Cy Lng Thc v Thc v Thc Phm phi hp vi cc c quan nghin cu khc( Vin khoa hc k thut nng nghip Vit Nam v Vin di truyn Vit Nam, Trng i Hc Nng Nghip H Ni) tin hnh nghin cu.-

Nm 1974 1976, cc cn b ca tri ging rau An Hi Hi Phng

chn lc c th lin tc t tp on ging c chua ca Nht Bn v a ra ging HP-1, HP-2, HP-3,HP-5. Trong c ging HP-5 c nng sut cao nht, chu su bnh kh, thch hp trng v Xun h nhng khi chn vai qu c mu xanh, HP-5 c cng nhn ging quc gia nm 1988( Theo T Th Cc, Hoang Ngc Chu, Nghim Th Bch H, 1994). T nm 1973 n 1984, T Thu Cc tin hnh nghin cu 100 mu ging c chua, gm c cc ging a phng v cc ging nhp ni. Kt qu cho thy, L.race migerumcos l ging c kh nng chu bnh tt nht, tip theo l ging Php s 7, BCA-1, Cuba, Ruko11 v BCA-3 (theo T Thu Cc). + Giai on 1986 1990: Nghin cu to ra mt s ging rau, trong c 2 ging C Chua l ging s 7 v ging 214. Bt u 1991, t mt s ging C Chua qu nh mu vng mang m s 2 trong vn tp on( ngun gc Nht, i Loan), GS.TS V Tuyn Hong, o Xun Cnh, o xun Thng v cng s p dng phng php chn dng phn lp v chn lc. n 1994 thu c dng C Chua vng n nh v cc c im sinh hc, c kh nng chng chi bnh tt thch hp gieo trng v ng, t tn C Chua vng( Theo AVRDC, 2003) + Giai on 1991 1995: Kt qu ti Nghin cu chn tao ging v xy dng qu trinh thm canh 1 s loi rau thuc chng trnh KN-01-02, a ra 1 s ging c cht lng nh: Hng Loan, SB2, SB3.

+ Giai on 1996- 2000: Cc ti nghin cu v ging rau c b tr trong chng trnh cp nh nc KC08 v chng trnh ging cy trng vt nui ca B Nng Nghip v Pht Trin Nng Thn. Giai on ny c nhiu nghin cu i vo chiu su, nhiu ging lai F1 cng qu trnh sn xut ht lai c xy dng.T tp on ging c chua c ngun gc t Mondavi, tc gi Nguyn Hng Minh v Kiu Th Th (HNN) chn lc thnh cng ging c chua MV1 v c cng nhn ging quc gia nm 1996. Ging c c im sinh trng 90 100 ngy, c kh nng chu nng tt, m cao, thp khc nhau, nng sut cao, qu chc, t dp nt, mu ti, chng chu tt vi bnh xon l (Nguyn Hng Minh, Kiu Th Th, 1998). T nm 1994 1997, V th Tnh( Vin Nghin Cu Rau Qu) chn lc thnh cng C Chua chi nhit VR2 .Ging ny c c im qu nh, chc, u, cht lng tt v ging c khu vc ha 1998. T nm 1994 n nay, chng trnh chn to ging C Chua u th lai ca Trng i Hoc Nng Nghip H Ni do PGS.TS Nguyn Hng Minh nghin cu a ra quy trnh cng ngh sn xut ht lai F1 c chua trn quy m i tr Vit Nam thng qua kh c v th phn cy m bng th cng. ng thi cng a ra c nhiu ging c chua lai trin vng c sc cnh tranh ln nh: HT5 (khu vc ha nm 1999), HT7 (cng nhn ging quc gia 9/2000), HT21, HT42, HT160, HT144 (c chua mini). a s cc ging lai mang nhn hiu HTu l cc ging c kh nng chu nng v khng virus tng i. Nm 2004, thng hiu dnh cho nhng ging c chua mang tn HT chnh thc c xc lp (Nguyn Hng Minh, Kiu Th Th, 2000). Qu trnh nghin cu v cng ngh sn xut ht ging c chua lai v to ging c chua lai c sc cnh tranh nc ta c tin hnh t nm 1994, thc hin trung bnh 40 50 t hp lai/nm. Nm 1997 2000 thc hin trung bnh 50 t hp lai/nm; t 2001 2006 thc hin 80 100 t hp lai/nm. u nm 2004, HT21 c cng nhn khu vc ha v pht trin sn xut i tr. Cc ging HT42, HT160 cng ang c th nghim a ra sn xut. Giai on ny 1 s ging C Chua t th

chn lc (ging thun) phc v cho ch bin c a ra PT18( Vin Nghin Cu Rau Qu), C95(Vin cy lng thc v thc phm) + Giai on 2005 2006 dn nay: Sau nhiu nm pht trin sn xut C Chua ti 2004-2005 t din tch kh ln nc ta.Tuy nhin s pht trin t ca cc ging nhp ni, nguy c cc dch bnh ngy cng cao. T nm 2005-2006 bng pht dch virus rt mnh vng sn xut C Chua ln dn n din tch C Chua gim mnh. Vn chn to ging kh nng chng chi bnh virus.Ti Trng i Hoc Nng Nghip H Ni kt qu chn to ging C Chua mini thnh cng v nm 20062007 ging C Chua mini HT144 a vo sn xut i tr phc v cho ni tiu v xut khu( ng hp nguyn qu). 2.3.3 Tnh hnh nghin cu v sn xut c chua hu c trn th gii v Vit Nam. 2.3.3.1 Tnh hnh nghin cu v sn xut c chua hu c trn th gii. Nhng ngi tin phong nh Rudolf Steiner, Robert Rodale, Sir Albert Howard v b Eva Balfour ln u tin xut bn cun sch tng ca h v nng nghip hu c vo nhng nm 1920, 1930, 1940, n dn hon thin v xc nh c th no l phong tro sinh hc v nng nghip hu c. H nu ra s quan tm ch v c s sinh hc ca ph t v mi lin h ca n vi sc khe ca ngi v ng vt. Ln mnh cng vi cc hot ng ca cc nh tin phong, xut hin nhm cc nh nng dn chu u, M pht trin theo hng ny. n nhng nm 1940, 1950 m hnh ca nhng nh sn xut hu c c hnh thnh. Vn thanh tra, gim st c nu ra, c thc hin v hnh thnh cc tiu chun, h thng pht trin chu u, M v c. Nm 1970, ln u tin cc sn phm hu c c ra i. Trang tri hu c c pht trin rt nhanh hu ht cc nc chu u vo nhng nm 1990. T nm 1988 ti nm 1999 tng din tch sn xut hu c tng ln ti 46,2%. Nhng nm gn y tng din tch hu c chu u hng nm tng ln trung bnh khong 30%/nm.Vo u nm 2000, din tch hn 3 triu ha c qun l vi

hn 100.000 trang tri hu c trn nhiu nc chu u, chim ti 2% t nng nghip. S trang tri hu c tng t 830 nm 1990 ln 5300 trang tri sn xut nng nghip hu c nm 2000(Ngun TS. L Vn Hng V KHCN, B NN & PTNT).

2.3.3.2 Tnh hnh nghin cu v sn xut c chua hu c Vit Nam. Nng nghip Vit Nam vi hn 4000 nm lch s, l nn nng nghip hu c bi s pht trin t nhin ca n. T nhng nm 1960, c bit sau ngy gii phng min Nam, vi nhiu ging cy trng mi c p dng trong sn xut, h thng ti tiu c ci to v m rng, din tch ti tiu c tng ln, phn ha hc v thuc tr su c dng vi s lng ln. Vic p dng cc ging cy trng mi vo sn xut cng l nguyn nhn lm mt dn i mt s cc ging cy trng truyn thng, lm gim s a dng sinh hc v lm tng thit hi bi dch hi cy trng. Khi s dng qu nhiu lng phn bn ha hc v cc loi thuc bo v thc vt mang li nh hng xu n mi trng.Mt s lng ln thuc bo v thc vt d tha tn ti trong t, nc v gy nhim mi trng. Lng thuc ny s dng khng hp l dn ti s hnh thnh tnh khng thuc ca su hi, nh hng ca d lng thuc bo v thc vt l tc ng xu ti sc khe con ngi, ng vt, v mi trng sng. Nhng hn ch ca cuc cch mng xanh v cng nghip ha nng nghip, dn n nhiu nc quay tr li vi nng nghip hu c (trong c Vit Nam). Ti Vit Nam trin khai th nghim phng php canh tc hu c trn cy rau, la, cam, vi v c nc ngt ti cc tnh Lo Cai, Tuyn Quang, Bc Giang, Bc Ninh, Vnh Phc, Hi Phng. PHN III NI DUNG V PHNG PHP NGHIN CU

3.1.Vt liu, a im v thi gian nghin cu. 3.1.1. Vt liu nghin cu. Th nghim trn bn ging: - PT18: l ging c chua c dng hnh sinh trng hu hn do Vin Nghin cu Rau qu chn to t cc ging c chua nhp ni t Trung tm pht trin rau chu (AVRDC), c B NN-PTNT cng nhn l ging Quc gia v cho php a vo sn xut i tr t thng 8 nm 2004. PT18 c thi gian sinh trng ngn (100-120 ngy), tn gn, phn cnh t, kh nng khng bnh tt c bit vi bnh ho xanh vi khun. Ging c tim nng nng sut cao 45-50 tn/ha, cht lng tt vi Brix t 4,8-5,2, pH thp 4.5, c bit ging c kh nng chu mt s bnh xon l virut rt tt. Nng sut ca FM20 c th t 40-45 tn/ha trong v xun h v 45-50 tn/ha trong v ng xun. - HPT10: ging c dng hnh sinh trng bn hu hn, cy sinh trng pht trin tt cho nng sut cao c hai thi v thu ng v v ng xun.kh nng chng chu bnh kh. Thi gian sinh trng 102-130 ngy, chiu cao trung bnh khong 120 cm. Thi gian bt u cho thu hoch 70 ngy sau trng. Qu c dng hnh tr trn, khi chn c mu m, nng sut cao 40-50 tn/ha v thu ng, 60-65 tn/ha v ng xun, qu c cht lng cao hm lng cht kh ho tan khong 5 Brix, thch hp cho c n ti v ch bin. - HT42: l ging sinh trng hu hn, do PGS.TS. Nguyn Hng Minh v cc cng s chn to ra vo nm 2003 v trng th nghim sn xut 2004. C chua lai HT42 thuc dng thp cy, mau t, thn chc, sinh trng khe, b l dy, c kh nng pht nhnh, ti sinh mnh, ra hoa r v nhiu hoa, u qu tt nhiu iu kin nhit

. Loi ging ny c khu v ngt, tht qu chc mn, vn chuyn m khng gy hng. 3.1.2. a im v thi gian nghin cu. - a im: Trung tm nng nghip hu c Trng i Hc Nng Nghip h Ni - Thi gian nghin cu: Th nghim tin hnh vo v Thu ng, t thng 8/201112/2011 3.2. Ni dung nghin cu. - Tnh hnh sinh trng, pht trin ca cc ging c chua trong iu kin canh tc hu c. + ng thi tng trng chiu cao v s l ca cc ging. + Cc giai on sinh trng trn ng rung. - c im cu trc qu ca cc ging c chua trong iu kin canh tc hu c. - Nng sut v cc yu t cu thnh nng sut ca cc ging c chua trong iu kin canh tc hu c. - Tnh hnh su bnh ca cc ging c chua trong iu kin canh tc hu c 3.3. Phng php nghin cu. 3.3.1 Cng thc th nghim Mi ging l 1 cng thc: CT1: PT18 CT2: FM20 CT3: HPT10 CT4: HT42 3.3.2.B tr th nghim. * Th nghim c b tr theo phng php khi ngu nhin hon chnh (RCB) vi 3 ln nhc li v 4 cng thc.S th nghim l 12 . Din tch mi 5m2, tng din tch TNo l 60 m2 3.3.3. S th nghim Ln nhc li Cng thc

I II III 3.4. K thut trng trt. Thi v

CT1 CT3 CT4

CT2 CT4 CT3

CT3 CT1 CT2

CT4 CT2 CT1

- V Thu ng : Gieo thng 8 dng lch, trng cui thng 9, bt u thu hoch vo cui thng 11 Lm t: Khng p t qu nh thnh dng t bt. Lung c chua c chiu rng 110-120cm, rnh rng 20-25cm, cao 30cm. Cc lung b tr theo hng ng - Ty. Gieo ht v ng cy con Lng ht ging gieo: 100-150 cho 1ha. Trc khi gieo ht nn ngm ht trong nc m 40-50oC trong khong 3 gi. Sau , cho ht vo ti vi bc giy kn. ch kn. Sau khong 3-4 ngy r mc th em gieo vo vn m. Sau khi gieo ht u trn mt t, ri 1 lp tro mng, trn ph mt lp rm mng v ti nc c m. Sau khi gieo khong 30-40 ngy, cy t 5-6 l, c th em trng. Mt trng: Mt trng c chua ty thuc vo c im ca ging, mc ph nhiu ca t nhng c th b tr nh sau: + Hng cch hng 70cm, cy cch cy 55 - 60cm. + Sau khi trng n nh t vo gc cy v lm bng phng t chung quanh gc. + Trng xong ti nc cho c chua ngay Phn bn t nng sut cao c chua i hi nhiu cht dinh dng. Lng cht dinh dng hp th ty thuc vo kh nng cho nng sut ca ging c chua, tnh trng t, iu kin trng V giai on tng trng v pht dc ca cy trng lp nhau v nhu cu cy cn cht dinh dng cho n khi tri chn, do vic bn lt, bn thc nhiu ln, gip tng hiu qu s dng cht dinh dng cho cy v tng nng sut. Phn ln cht

dinh dng nui qu c cy hp th sau khi tr hoa, do cy yu cu cht dinh dng nhiu nht khong 10 ngy sau khi hoa n cho n khi tri bt u chn. Lng phn s dng cho 1 ha -Hu c : 20 30 tn phn chung c hoai -Hu c vi sinh Sng Gianh 2 tn Cch bn phn: -Bn lt: ton b lng phn hu c + ton b phn hu c vi sinh Sng Gianh -Bn thc : sau khi trng 10 15 ngy ta tin hnh ti dinh dng, cc ln sau 3 5 ngy ti dinh dng mt ln. Chm sc : Nhu cu nc Nhu cu nc ca c chua ty thuc vo giai on pht trin ca cy. Khi cy ra hoa u qu l khi cy cn nhiu nc nht. Lng nc ti cng nn thay i ty thuc vo lng phn bn, mt trng v loi t. Khi bn nhiu phn m v trng dy, cn thit gia tng lng nc ti. Sau khi trng phi ti nc lin tc trong 1 tun, mi ngy ti 1 ln vo bui sng. Sau khi cy bn r th 2-3 ngy ti 1 ln. Khi cnh l pht trin nhiu th lng nc ti mi ln phi c tng ln. Thi k c chua ra hoa v qu nh l lc cy cn nhiu nc nn t lun phi c gi m. Vun xi Vic vun xi c chua cn c tin hnh trc khi cy ra hoa kt qu. T lc trng n khi cy c 20 ngy vun gc 2 ln: ln th nht sau khi trng khong 8-10 ngy v ln th 2 cch ln th nht 1 tun. Lm gin Vic lm gin c tin hnh sau khi cy ra chm hoa th nht.Tin hnh lm gin c chua theo kiu hnh ch A. Cy vn ti u th buc thn cy vo cc ti . Bm ngn v ta cnh

Mc ch bm ngn ta cnh l tp trung cht dinh dng nui qu. C hai cch bm ngn ta cnh, ty thuc vo c im ca tng ging cy th dng cch khc nhau. i vi ging c chua ngn ngy, ta nn ta cnh ch li mt thn m: Mi cy ch li mt thn chnh, cc mm xut hin nch l 3-4cm l vt i ngay.Ta cnh c lm thng xuyn 4-5 ngy mt ln. Sau khi trn thn chnh c chm hoa qu nh mun (4-5 chm) th tin hnh bm ngn. i vi ging c chua v hn v bn hu hn, tin hnh bm cnh nhng vn li mt cnh t thn chnh di nch cng l pha di chm hoa th nht. (Tt c chi non v cnh khe ct ht). Bm ngn khi cy ra c 4-5 chm qu. Tnh t chm qu cui cng ln cha li hai l, phn ngn pha trn bm i. Ta l gi: Vo cui thi k sinh trng ca cy, c chua c nhng l gi vng cn phi ta b lm thong rung cho cy pht trin tt.

3.5 Cc ch tiu theo di3.5.1 Cc giai on sinh trng trn ng rung. + Thi gian t trng n ra hoa: Khi c 40% - 50% s cy s cy trong th nghim n hoa chm 1). + Thi gian t trng n u qu: Khi c 40% - 50% s cy trong th nghim u qu chm 1. + Thi gian t trng n qu bt u chn: khi trn 40 - 50% s cy trn th nghim c qu chn chm 1. 3.5.2 ng thi tng trng chiu cao v s l ca cc ging. + ng thi tng trng chiu cao cy(cm), o t c r n nh sinh trng; o m 7 cy/cng thc/ 1 ln nhc li, c 7 ngy/ ln. + ng thi ra l v s l trn thn chnh. m s l tht t gc n nh; o m 7 cy/cng thc/ 1 ln nhc li, c 7 ngy/ ln. 3.5.3 Mt s ch tiu sinh trng v cu trc cy.

+ Dng hnh sinh trng: v hn, hu hn hay bn hu hn. + Chiu cao t gc n chm hoa th nht (cm). + S t t gc n chm hoa th nht. + Chiu cao cui cng (cm):o t c r n nh sinh trng. 3.5.4 Mt s c im hnh thi, c im n hoa. + Mu sc l: quan st mu sc v phn bit l mu xanh sng, xanh trung bnh v xanh m. + c im n hoa: quan st v phn ra n hoa ri rc, n hoa tp trung. + Dng chm hoa: n gin (hoa ra trn 1 nhnh chnh), trung gian (hoa ra trn 2 nhnh chnh) v phc tp (chm hoa chia thnh nhiu nhnh 3.5.5 Mt s ch tiu v cht lng qu: + t tht qu: quan st v phn bit rt t, t, kh nh, kh. + c im tht qu gm cc dng: th sng, chc mn, chc b, mm mn, mm nt. + nh gi hng v qu: c hng, khng r v hng ngi. + Khu v nm c cc mc: chua, chua du, nht, ngt du, ngt. + Brix: s dng my o Brix. + T l qu nt sau ma. Cc ch tiu t tht qu, c im tht qu, hng v qu, khu v c nh gi theo phng php ca Trung tm nghin cu v pht trin ging rau cht lng cao trng i hc Nng nghip H Ni a ra. 3.5.6 Nng sut v cc yu t cu thnh nng sut: + Tng s qu/cy + Khi lng trung bnh/qu (g) + T l u qu (%) = (s qu u/s hoa)* 100% Theo di trn 5 chm u ca cy (t di ln), theo di 5 cy/cng thc, tnh t l u qu trn tng chm v t l u qu trung bnh.

+ S chm qu/cy (chm) + Nng sut c th (g/cy) = PTB x( Tng s qu/cy). 3.5.7 Mt s ch tiu v hnh thi qu v chc ca qu + Dng qu: tnh theo cng thc ch s hnh dng qu I = H/D Trong : H l chiu cao qu ( cm) D l ng knh qu ( cm ) I>1: Dng qu di I 1,06: Dang qua dai qua h: Chiu cao qua I = 0,8 - 1,06: Dang qua tron d: ng kinh qua I < 0,8: Dang qua det Qua bng s liu cho thy, c 2 ging dng qu di l FM20(1.14) v I = H/D HPT10(1.15), cn li 2 ging PT18(0.96) v HT42(0.95) dng qu trn. 4.7.4. S ht trn qu. S ht trn qu ph thuc vo c tnh di truyn ca tng ging, ht l kt qu ca qu trnh th phn, th tinh nn n cng phn nh kh nng chu nhit v thch ng vi iu kin ngoi cnh ca cc ging. Nu ging no c nhiu ht chng t ging thch ng tt vi iu kin ngoi cnh nhng c tnh nhiu ht li nh

I: Chi tiu hinh dang

hng khng tt n th hiu ngi tiu dng v ch bin. Cho nn mc tiu chn ging c chua t hoc khng ht c cc nh chn ging quan tm nhm p ng th trng. Qua bng 4.10 cho thy, s qu trn ht dao ng trong khong t 74.78 n 149.47 ht. Ging FM20 c s ht trn qu nhiu nht (149.47 ht) v ging HT42 t nht l 74.78 ht. 4.7.5. S ngn ht. S ngn ht l c tnh c trng cho tng ging. Ch tiu ny c dng nh gi chc qu. Nu ging c s ngn ht t th qu chc v nhn hn nhng dch qu li t nn nh hng n cht lng hng v qu. Nu t hp no c s ngn ht nhiu th rng ln, qu c chc km dn n kh vn chuyn v bo qun sau thu hoch. V vy chng ta phi nghin cu tm ra s ngn ht hp l m vn m bo chc qu v cht lng qu. Qua th nghim cho thy, cc ging c s ngn ht dao ng t 2.70 n 3.03 ngn ht/qu. Trong ging HPT10 c s ngn qu nhiu nht (3.03 ngn ht/qu), cn cc ging khc c s ngn ht gn nhau nh: ging PT18( 2.70 ngn ht/ qu); FM20( 2.72 ngn ht/ qu); HT42( 2.75 ngn ht/ qu).

4.8. Mt s ch tiu v cht lng. 4.8.1. Brix. Brix l ch tiu xc nh hm lng cc cht ha tan trong dch qu. y l c trng di truyn ca tng ging nhng t nhiu cng b nh hng ca iu kin ngoi cnh, c bit l lng ma trong giai on qu chn v thu hoch. Nu trong giai on qu chn thu hoch gp ma nhiu th s lm Brix gim ng k. Bng 4.11. Mt s ch tiu v cht lng qu T STT hp lai Brix dy tht qu(m m) 3.79 3.97 4.37 3.67 5.12 5.34 6.18 5.27 c im tht qu Chc b Chc mn Chc mn Chc mn t tht qu Kh nh Kh nh Kh nh Kh nh Khu v nm Ngt di Chua nh Nht Ngt di Hng v C hng C hng C hng C hng

1 2 3 4

PT18 FM20 HPT10 HT42

Qua theo di v phn tch, Brix ca ging nm trong khong t 3.67 n 4.37 trong ging c Brix thp nht HT42(3.67) cn HPT10 c Brix cao nht (4.37).

4.8.2. dy tht qu. dy tht qu to nn chc v cht lng qu c chua. Nhng ging c dy cng cao th cng c th bo qun c lu v vn chuyn tt hn ng thi cht lng qu cng tt hn. Kt qu bng 4.11 cho thy, cc ging c dy tht qu dao ng t 5.12 n 6.18mm. Ging c dy cao nht HPT10(6.18mm), ging c dy thp nht PT18(5.12mm), cn ging FM20 cng c dy tht qu kh cao(5.34mm). 4.8.3. c im tht qu. c im tht qu l ch tiu quan trng nh gi cht lng ch bin, bo qun v vn chuyn ca qu. c im tht qu chia lm cc loi sau: th sng, chc mn, mm mn, mm nt. Trong chc mn v mm mn l 2 loi c la chn. Qua th bng s liu cho thy, tt c ging u c tht qu thuc dng chc mn hoc chc b. t tht qu cng l mt c tnh c trng cho tng ging. t tht qu c chia ra: kh, kh nh (t nh), t. Qua phn tch cho thy, tt c cc ging u c tht qu thuc dng kh nh. 4.8.5. Khu v v hng v. - Khu v nm c nh gi theo cm quan n ti chia thnh cc mc: ngt, ngt du, chua du, chua. Quan phn tch v nh gi cm quan thy rng, a s cc ging mc ngt di, ch c FM20 mc chua du. - Hng v cng l mt trong nhng ch tiu nh gi cht lng qu. Cng nh khu v th hng v cng c nh gi bng cm quan v chia thnh cc mc: c hng, khng r, hng ngi. Qua nh gi th tt c cc ging trong th nghim u c mi c trng cho c chua ( c hng).

PHN V KT LUN V NGH 5.1. Kt lun T kt qu nghin cu cc ging c chua v Thu ng nm 2011, chng ti rt ra mt s kt lun sau:1. Cc ging trong th nghim hu ht u l cc ging ngn ngy, thuc loi hnh

sinh trng hu hn ch c HPT10 l bn hu hn, thch hp cho trng v Thu ng, thi gian t trng n chn dao ng 60 80 ngy.2. T l u qu ca cc ging th nghim t kh cao, dao ng t 81.05 n

85.41%. Hu ht cc ging u c t l u qu cao trn 80%, trong ging PT18 c t l u qu cao nht (85.41%).3. Hu ht cc ging th nghim c t l bnh m en vi khun kh cao, i din c

HT42, PT18, HPT10. Ch c ging FM20 c t l bnh m en vi khun thp nht v Thu ng cn c tip tc theo di thm cc v sau. 4. S chm qu trn cy dao ng t 7.24 n 10.43 chm. Trong , HT42 c s chm cao nht (10.43 chm/cy).Cc ging c tng s qu trn cy ca cc ging dao ng trong khong t 17.29 n 30.43 qu/cy v cao nht l HT42 (30.43 qu/cy). Nng sut c th ca cc ging dao ng trong khong t 1367.41 n 1743.64( g/cy). Ging HT42 c nng sut c th cao nht (1743.64 g/cy). Ging c nng sut th nghim( kg/)cao nht l HT42 t 17.43kg/. 5. C 2 ging dng qu di l FM20(1.14) v HPT10(1.15), cn li 2 ging PT18(0.96) v HT42(0.95) dng qu trn). Brix ca cc ging nm trong khong t 3.67 n 4.37 trong , HPT10 c Brix cao nht (4.37). Cc ging c dy tht qu dao ng t 5.12 n 6.18mm. Ging c dy cao nht HPT10(6.18mm).

Tt c cc ging th nghim u c tht qu chc mn v chc b, kh nh, c v ngt di v u c hng v c trng ca c chua. 5.2. ngh ngh tip tc nghin cu, th nghim cc ging HT42(nng sut cao) v FM20(c kh nng chng chi bnh tt) cc ma v khc c kt lun chnh xc hn, rt ra ging phc v sn xut.4.1.1 T l ny mm v thi gian sinh trng ca 6 ging c 4.1.2 Chiu cao cy v tc tng trng chiu cao cy ca 6 ging c 4.1.2.1 ng thi tng trng chiu cao cy 4.1.2.2 Tc tng trng chiu cao cy 4.1.3 ng knh tn v tc tng trng ng knh ca 6 ging c

1.

o Xun Thng(2005) Kt qu thc hin nghin cu ging c chua, da chut M s KC06.DA10NN, tr10 15

2. Tt Li (1999), nhng cy thuc v v thuc Vit Nam, nh xut bn y hc, H Ni 3. B Nng Nghip v pht trin Nng thn (2005), 575 ging cy trng nng nghi mi, nh xut bn nng nghip H Ni. 4. Nguyn Vn Hin v ctv (2000), Chn ging cy trng, Nh Xut Bn gio dc H Ni. 5. Nguyn Hng Minh, Kiu Th Th (2000), Bo co cng nhn ging cy trng ti H Ni, 9/2000, B nng nghip v pht trin nng thn. 6. Nguyn Hng Minh (2000), Chn to ging C chua trong chn to ging cy trng, tr 300 343 7. L Trn c 1997, nhng cy thuc v v thuc Vit Nam, nh xut bn nng nghip, H Ni. 8. T Th Cc (1985) Kho st mt s ging c chua nhp ni trng trong v xun h ti GL HN, lun vn PTS.KHKTNN, i Hc Nng Nghip H Ni 9. T Th Cc, H Hu An, Nghim Th Bch H (2007), Gio trnh cy rau, nh xut bn nng nghip, H Ni, tr 117 143. 10.Mai Phng Anh v ctv (1996) , rau v trng rau, , nh xut bn nng nghip, H Ni, tr 164 176. 11.Kuo 0.G, Openna R.T and ChenT.T(1998), Guides for Tomato Production in the tropics and sudtropics; Asian Vegetable Research and Development center, Unpudlished techical Bullention no, PP.1 73 12.Kallo.G. (19987) Vegetable breeding, Volume III. CRC press, Tnc, Bocaration, Florida,US, pp. 60 75 13.Jenkin. J. A (1948), the origin of cultivated tomato E con. Bot.Z, pp. 379 - 392

Bng 4.10 : Kh nng ra hoa v u qu ca su ging c pho

NT 1

s hoa / cy 40,67

s qu / cy 32,08

t l u qu (%) 78,88

2 3 4 5 6

42,33 43,67 38,33 47,03 44,23

36,89 33,89 25,33 42,67 34,67

87,15 77,6 66,08 90,93 78,39

* T l u qu v s qu trn cy l nhng ch tiu quan trng trong vic to nn nng sut ca ging. nh hng n nhng ch tiu ny l hng lot cc yu t nh iu kin ngoi cnh,k thut chn sc. Ngoi ra yu t di truyn cng c nh hng khng nh n t l u qu v s qu ca cc ging c. Qua bng 4.10 trn ta thy