Tgp chi Khoa hpc Tru&ng Dpi hpc Cdn Tha Phdn B: Ndng nghiip, Thuy sdn vd Cdng nghf Sinh hgc. 35 (2014): 23-30
Tap chl Khoa hoc Tru'dng Oai hoc C l n Tha website: sj.ctu.edu.vn
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DANH GIA KHA NANG RA HOA RAI VU
TREN CAY XOAI CAT HOA LOC (MANGIFERA INDICA L.) TAI XA HOA H I T N G , HUYEN CAI BE, TINH TIEN GIANG, NAM 2012 Tran Van Hau', Nguyin Chi Linh' va Nguyen Anh Tuan^
' Khoa Ndng nghiip <^ Sinh hgc ung Dung, Trudng Dgi hgc Cdn Tha
^ Sinh viin ldp Khoa hgc cdy Irdng khda 3 7, Trudng Dgi hgc Cdn Tha Thong tin chung:
Ngdy nhdn: 05/06/2014 Ngdy chdp nhgn: 30/12/2014 Title:
Evaluation of the capability of year round flowering induction on Hoa Loc mango (Mangifera indica L.) in Cai Be District. Tien Giang Province
Tirkhda:
Xoai cdt Hoa Lgc, paclobulrazoi Thiourea, rdi
vy Keywords:
Cat Hoa Loc' mango, paclobub-azoi thiourea, year round flowering
ABSTRACT
This study was aimed lo evaluate the capability of year round flowering induction on Hoa Loc mango in Hoa Hung commune, Cai Be district, Tien Giang province, from December 2011 lo March 2013. The experiment of this study had four treatments arranged in completely randomized design; each treatment equals lo one flowering induction season with three replications, each of which was one demonstration including 30 trees. Seasons offlowerii^
induction included on (Dec-Jan), late (Mar-Apr), early (Jun-Jul) andofl'(Sept- Oct) season. The flowering induction protocol proposed by Tran Van Hau el ai (2011) was applied, in which paclobutrazol at 1-2 g a.i.m'' canopy diameter was used to help the flower initiation ofmerislem, 2.5-3 months later Thiourea at 0.3-0.5% was used lo induce flowering; one week later Thiourea was sprayed again at the half-reduced concentration. Results showed that year round flowering induction on Hoa Loc mango affected flowering ratio, number of flower per inflorescent, hermaphroditic flower portion, fruil set ratio, fruit weight, fhiit/lree yield and pest damage Off-season had high flowering and fhiit sel rate, hence high fruit yield despite high ratio of young fruit abscission.
Anihracnose was the most devastating on inflorescence and fruit on late and offseason, whereas fhrips were primarily destructive on fruit set stage of on and early season.
TOM T A T
De ldi dugc thifc hiin nhdm ddnh gid khd nang xit ly ra hoa rdi vu xodi cat Hoa Lgc tgi xa Hoa Hung, huyin Cdi Be, tinh Tidn Giang lit thdng 12/2011 den thdng 3/2013. Thi nghiem cd bdn nghiim thuc dugc bd tri theo thi thiic hoan toan ngdu nhien. moi nghiem thicc Id mot vu. ba ldn lap lai mdi lap lai la mgt mo hmh co 30 cay. Cdc thdi vii x,t ly ra hoa trong nSm la vu thugn (12-1), vg mugn (3-4). vu sdm (6-7) vd vg nghfch (9-10). Cdy xodi duac xu ly ra hoa theo quy trmh cda Trdn Vdn Hdu et ai (2011), trong dd xii ly paclobutrazol >
tgo mam hoa vol lieu lugng 1 g a.i./m dudng kinh tdn, 2,5-3 thdng sau kich Ihich tro hoa bang cdch phun Thioure ndng dg 0.3-0,5%. phun ldn hai sau bdy ngay vai nong dg gidm 50%. Kit qud cho thdy xii ly ra hoa rdi vu xodi cdt Hoa ' Lgc CO anh huang den li lg ra hoa, ldng .id hoa/phdt hoa. tl lg hoa lu&ng linh. li I? dau trai. trgng lugng trdi, nang sudt trdi/cay va sau benh gdy hgi. Vu nghfch l CO 111? ra hoa, dgu trdi cao nen dgt ndng sudt cao mac du cd ti H rung trdi caa Benh than Ihu gdy hgi phdt hoa vd trdi nhiiu nhdl trong vg mugn vd vy nghich trong khi bl IrTgdy hgi phdt hoa giai doan ddu trdi chi, yiu d vu miia va
Tpp chi Khoa hpc Tru&ng Dgi hpc Cdn Tha
1 MCfDAU
Xoai cat Hda Ldc la logi cdy dn ttai chu lyc, cd gia fri kinh ti cao, dugc frdng nhieu d cac tinh miin Ddng Nam Bp va nhat la d Ddng bdng sdng Cfru Long (DBSCL). Theo Cue Trdng Trpt (2013) di^n ti'ch trdng xodi d Nam Bd tfr nam 2008 din nay i n dinh d miic ban 62.000 hecta, san lupng nam 2011 udc dgt 570.000 tin. Theo Batten va McConchie (1995), yiu td quyit dinh sy ra hoa, xoai Id nhiit dd thap. Nhiet dp <20''C la yiu to quyit dinh cho su ra hoa. Nhiing nam cd nhiit dp Ignh thip vd keo dai cdy xodi se ra hoa nhieu vd nlia vudn si triing mda. Ngugc lgi, nhung ndm khdng cd diiu kiin nhiit dd lanh, cdy xodi ra hoa it, nha vudn se that miia. Do dd, niu khdng cd biin phap dieu khiin cho xoai ra hoa nang suit va thdi vy xodi phy thudc vao dieu kien ty nhien va se xuat hiin di^p khuc "dugc miia mit gia". Dieu khiin xoai ra hoa rdi vu la biin phdp di kio ddi thdi gian thu hoach, chu ddng dugc san lugng hang hda va on dinh nang suat. Tir ket qua nghien ciiu ky thugt xii ly cho xoai ra hoa miia nghich (Trdn Van Hdu, 2005), Trdn V5n Hdu et aL (2011) dd nghiin ciiu xdy dung quy frinh rdi vu xoai cat Hda Lpc tgi huyin Cao Ldnh, tinh Ddng Thap. Muc tieu ciia de tai nham danh gid kha ndng xii \^ ra hoa rdi vy xodi cat Hda Lpc bing quy trinh ciia Trin Vdn Hdu et ai (2011) tgi xd Hda Hung, huyen Cai Be, tinh Tiin Giang.
2 PHU"aNG PHAP NGHIEN CUtJ Thi nghiem dugc thuc hiin tir thang 12/2011 din tiidng 3/2013 frin cay xoai cat Hda Ldc 15 ndm tuii lgi vudn cua cac hd ddn d dp Hda, x3 Hda Hung, huyin Cai Be, tinh Tiin Giang. Thi nghiem dugc b i fri theo the thiic hodn toan ngau nhien, cd bin nghifm thurc tuong iing vdi bin miia vy sdn xuit xoai, mfli nghiim tiuic lap Igi ba lin, mdi lin ldp lai tuong iing vdi 30 cay xodi. Cac thdi vu xii ly ra hoa frong nam la vy thudn (12-1), vu mupn (3-4), vy sdm (6-7) va vy nghich (9-10). Xfr \-j ra hoa theo quy trinh ciia Tran Van Hdu et al. (2011), frong dd xu IJ paclobutrazol (PBZ) tao mim hoa vdi liiu lugng 1 g a.i./m dudng kirih tan, 2,5-3,0 thdng sau kich thich tti hoa bing each phun Thioure ndng dp 0,3-0,5%, phun lin hai sau bdy ngay vdi ndng dp gidm 50%. Ngoai ra, trudc khi xii ly ra hoa, cay xodi dupe tia canh, kich thich ra dpt ddng diu, t^p ttung bang cdch bdn phan theo cdng thiic N:P;K vdi ti le 4-3-2 vdi liiu lugng tir 0,5-1,0 kg/cay. Tuy nhiin, do vy thugn gia xoai khd ri nhung chi phi phdng trir sau binb rdt cao nin rat it nhd vudn d xd Hda Hung xii ^ cho xoai ra hoa
Phdn B- Ndng nghiip, Th^ sdn vd Cdng nghi Sinh hoc: 35 (2014): 23-30 vao thdi vu ndy ma thudng kich thi'ch tti hoa vdo vu thudn frin nhiing cdy da ra hoa vy mudn hay vu nghich. Vdi quy trinh nay, nha vudn khdng xfr Iy PBZ tao mim hoa ma chi phun tbiouri kich tbich cho cay ra hoa tdp frung khi cd diiu ki^n nhiit dp thip. Chpn ngiu nhien 10 cdy ttong md hinh 30 cay, mdi cay danh diu ngau nhiin 10 phat hoa de theo ddi qua frinh ra hoa, sy dau ttai va phat ttiin ttai, ti If gay hgi cua sau benh. Ti Ii ra hoa ghi nhan bang each dim so chdi ra boa/tdng sd chdi ttong khung cd kich thudc 50 x 50 cm, mdi cdy dim 10 khung xung quanh tan cdy. Ndng suat dupe ghi nhgn bang each cdn trgng lupng tdt ca ttai trin cdy khi thu hoach. Trpng lupng trung binh ttdi ghi nhdn bdng each can ba trai tten cdy, sau dd dd chin phdn tich thanh phin trdi va phdm chit trdi. Hdra lugng vitamin C dugc xdc dinh theo phuong phap ciia Murin (1900, ttich ddn.bdi Nguyin Mmh Chan et al., 2005); hdra lupng TSS dugc xdc dinli bang each nghiin 5 gam thit frai chin sau dd len the tich 50 ml bing nude cat, lpc Idy dich va do bang may khtic xa ki ATAGO; ham lupng chit khd (%CK) dupe xdc dinh bdng each can frpng lupng raau ban diu (A) sau dd say khd d nhiit do 60°C din khi trpng lupng khdng ihay dii (B) va dupe ti'nh theo cdng thiic: CK (%) = B/A * IOO. Su gdy hai cua sdu binh dugc ghi nhan bang cdch dim sd phat hoa bi sau binh tin cdng ttong khung cd kich thudc 50 X 50 cm, mdi cdy dim 10 khung xung quanh ldn cdy. Cdc sd lieu ttong thi nghi$m dugc nhdp bdng phan mem Excel va phdn tich bdng phan mim SPSS. Sd liiu khi tupng dupe ghi nhan tfr thdng 12/2011 din tiiang 3/2013 tai dai klii tirang tiiiiy van tinh Vmh Long bao gdm nhiit dp thip nhit hang thdng, am dd luong dii hang thang va lupng mua trung binh hang thang (Hinh 1). Nhiet dd thip nhit ttung bmh"ffa^t^n^r/2012-ia 22,7°^ vd im do tuong dii tmng binh Id 87,19%, ddy Id diiu kiin thich hgp cho cdy xodi ra hoa tu nhien. Nhiit dp tiidp nhit trung binh frong thang 6/2013 la 25,6°C, tiiang 9/2013 la 24,3"C, thang 12/2013 la 24,2''C tao diiu kien thich hpp cho xoai ra hoa vy mudn (ra hoa vdo thang 4-6), vu nghich (ra hoa vao thang 7-9) vd vy sdm (ra hoa vao tiidi^ 10-12). Tuy nhiin, mua tdp trung tir thang 3/2012 din thdng 10/2012, am dp tuong ddi ludn cao fren 75%. Day la dieu kien thugn lpi cho benh than thu phat trien va gay hai. Hoang Huu Cu va Mai Van Tri (2003) cung cho biet ti I^ benh than thu va chi sd binh cd quan hi mdt thiit vdi lupng mua va am dp. Am dp cao, nhiit dp cao tfr thang 2-4/2012 ciing gdp phdn Idm cho bp tri gia lang mat so va gay nghiem frgng frin vudn xoai.
Tap ehi Khoa hoc Trudng Dai hoc Cdn Tha Phdn B: Nong nghiip, Thuy san vd Cdngnghi Sinh hgc: 35 (2014): 23-3i
9 10 1. K i J 3
Hinh l: LTfng mm, trung binh va Sm do tmmg dM trung binh hang thang (a), nhiet do trung binh hang thing (b) tir thang 12/2011-3/2013 t?i Vinh Long
Ngu6n. Dai khi luifrjg thiiy van linh VTnh Long, 2014 3 KET QUA VA THAO LCAN 3.1 Sn ra hoa
3.1.1 Tilerahoa
Ti le ra hoa khac biet co y nghia th6ng ke gifla cac vy (Hinh 2). Vu nghjch co ti le ra hoa cao (68,16%) khac biet co J nghia thdng ke voi cac vn khac. ICSt qua nay cho thiy ap d\mg quy trinh kich thich ra hoa ban| each xu ly PBZ t^o mam hoa, 2,5-3 thing sau tiln hanh kich thich tr6 hoa dat ti IS ra hoa cao trong miia ngiiich ciing nhu ca nam (Trin Van Hau, 2013). Theo quy trinh canh tic cua nha vuron, de kich thich cho xoai ra hoa vy nghich
nha vutm flurcmg c5t tia canh, bon phan it« kich thich cho cay ra dpt moi, tao diju kien cho cay xoa CO kha nang ra hoa va nuoi ttai, ttong khi 6 vu mSi nlia vudn chi kich thich cho cay tr6 hoa bang thioure khi c6 diiu kiSn nhiSt ib tliap vao thfcg 12-1 ma khong kich thich cho ciy ra dpt mdi. Tlljl ts vu miia 6 xS Hoa Hung huyen Cai Be, tinh Tib Giang nhu la mpt hinh thirc tang vy chd kMnj phai chuySn vu hay rai vy. Phavaphutanon et d (2000) khuydn cao ring, kich thich ra hoa chi co hieu qua khi cay khoe, co diy di cac chit carbohydrate bidn doi ttong cay.
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1
VuflnHn Vttraagn Vyt^ndi Vnsran •A-.1^^-;
Al&a VH
Hinh 2: Tt If ra hoa (%) ciia xoai cat Hoa Lpc fr nhinig thoi vu khac nhau trong nam tai huyen Cai Be, tinh Tien Giang, nam 2012-2013
3.1.2 Ddc tinh phdt hoa
Chieu dai phat hoa gjuu cac miia vy khdc biet khdng cd y nghia thdng ki nhung tong sd hoa/phat hoa va ti Ii hoa ludng tinh khdc biet co y nghTa
thdng ke (Bang I). Chiiu dai phat hoa trung binli'^
cdc miia vu Id 50,14 cm. Tdng sd hoa tren phat hoi d vu sdm va vu nghich nhiiu ban frong vy tiiu|i nhung khdc biil khdng cd y nghia so vai vu iti^
Ti Ii hoa luong tinh 6 vy thudn thdp han cac v
^gp chi Khoa hpc Tru&ng Dgi hgc Cdn Tha Phan B: Ndng nghiip, Thuy sdn vd Cdng nghi Sinh hpc: 35 (2014): 23-30 diac. Khdo sat dac diim ra hoa cua xoai cat Hda
^QC, Trdn Van Hau (2013) nhan thay phat hoa dai 55,9 cm c6 1.124 phdt hoa nhung ti Ie hoa luong :inh chi cd 3 7%. Theo Vu Cdng Hau (1996) till ti Ii loa ludng tinh thucmg thap tii vai phdn frdm din
60-70% nhung tiidng thudng chi vai chuc phdn tram. Gidng vd diiu kien thdi tiit cung anh hudng din ti If hoa ludng tinh (Trdn The Tuc et aL, 1998). Nhu vay, yiu Id mua vu cd dnh hudng lin tdng sd hoa fren phat hoa va ti Ie hoa ludng tinh.
Bdng 1: Chi^u ddi phat hoa, tdng sd hoa trin phdt hoa, ti 1$ hoa ludng tinh trin xoai cat Hda Ldc d nurog thdi vu khdc nhau t^i huyfo Cid Be, tinh Tien Giang, nam 2012-2013
Miia vu Vy thuan Vy mudn Vy nghich Vy sdm Trung binh
Chieu dai phit hoa (cm) 49,98 50,38 49,89 5032
Tong so hoa/
phat hoa (boa) 641,8"
656,8"
699,1' 696,7"
Ti If hoa Iir&ng tinh 50,14''
(%)
6tt,36' 58,80*
60,75"
F CV(%)
Ghi chu: Trong ciing mdi cdt nhiing sd cd chU theo sau gidng nhau khdc biil khdng coy nghta ihdng ke a miic y nghia 5% qua phep thU Duncan: ns: Khdc biil khdngy nghia thdng ki & muc y nghfa 5%; *: khdc biil cd y nghia Ihong ki &
muc y nghia 5%
3.1.3 Svddu trdi vd rung trdi non Ti Ii d^u frdi (tinh tfr khi hoa luong tinh chuyin sang raau xanh hay giai d o ^ dfrt d^u trdi) cua cac mda vu cd khac biet thong ki d raiic y nghia 5%
(Hinh 3). Vu nghich cd ti li dau trdi cao nhdt
1,52%) so vdi cdc thdi vy khac. Pham Thj Huong et ai (2003) cho biil nhift dp fren 25''C tiii ti Ii bao phdn md dat tfr 90-100% nhung nhiet dp tfr 20- 25''C thi ti If bao phdn md ciia hdu hit cdc gidng khoang 40% vd khi nhiit dp tu 15-20°C thi ti li bao phdn md tit 10-15%.
V\i4!t4n Vuffluon VuD^ich
l l
Ngtai|mfiii7c Hinh 3: Ti If (%) dau trdi xoai cdt Hda L$c a cac
tinh Tien Giang, Hiin tupng ryng frai non xuit hiin manh d giai d o ^ 10 ngdy SKDT va keo ddi cho tdi ngay thii 50 SKDT, sau dd gidm ddn vd dn dinh den Idii tim ho^ch (Hinh 4). Tr4n Van Hau (2013) cho rdng sy ryng trai diln ra manh nhdt vdo giai doan 10 ngdy SKDT, giai doan tii 20-40 ngay SKDT su ryng tim non van diin ra nhung gidm dan vd tu 40 ngdy SKDT din khi thu hoach tiii ti' Ie frdi cdn Iai frin phdt hoa gan nhu 6n djnh. Theo Chadha (1993) tiii
thdi vu khac nhau trong nam t^i huyen Cdi Be, Dam 2012-2013
su ryng frai non la mdt qua frinli sinh Iy phfrc igp, xuat hien fren nhiiu gidng va hdu hit cdc giai d o ^ frong qua trinh phdt friin frdi. Ti Ii trdi cdn Iai frin phdt hoa cao nhdt d vy thudn (81,04% d giai doan 50 ngdy SKDT) vd tiiip nhdt d vy nghich (32,65%
a giai doan 50 ngay SKDT), frong do d vy nghich hiin tupng rung frai xdy ra manh d giai doan 40- 50 SKDT.
Tgp chi Khoa hoc Tru&ng Dai hpc Cdn Tha Phdn B: Nong nghiip, Thiy sdn vd Cong nghi Sinh hpc: 35 (2014): 2^
-•-Viilhuin HB-VumuOn -A-Vyngjijch ^^-Vysdm
Hinh 4: S6 trdi con lai/phat hoa sau khi d a u t r a i ciia xoai c a t H d a L o c d n h u n g t h d i vy k h a c nhau t r o n g n a m t?i huy^n Cai Be, t i n h T i e n G i a n g , n a m 2012-2013
n i u bdn phan ddy d u cd tiii n | n g tir 700-800 g/triL Trdn Vdn Hau (2013) ciing cho rdng dung PBZ ^ Thiourea xii ly ra h o a Iam tdng U If ra hoa dan dli tang ndng suat cdy xoai.
Bdng 3 : T r p n g l u g n g t r u n g b i n h t r a i v i nang s u a t ( k g / c a y ) xodi c a t H d a Lpc d nhihig t h d i v u k h d c n h a u t^i h u y f n Cdi Bi, tinh T i l n G i a n g t r o n g n a m 2012-2013 3.2 Ti l i thdnh p h a n t r p n g l u p n g trdi
Ti If vd frdi, ti l i hat va ti If thil Udi ^ u a cac mua vy khdc biit khong y r ^ T a t h i n g ke (Bang 2).
Ti if vd frdi chiem 7,68%, ti le hat chiira 12,67%
vd ti l i thi trai chiim 79,65% so vdi trpng lupng frdi. K i t qud cho thay diing PBZ vd Thioure xii Iy ra hoa khdng Idm dnh hudng d i n li l i vd trai, ti le h^t va ti If thit trdi giiia cdc miia vy frong nam.
B a n g 2: T i If vo t r a i , ti le h ^ t va ti If thit t r a i xoai cdt Hda Lpc d n h u n g t h M vu k h a c nhau tai huyen Cdi B i , tinh Tien G i a n g t r o n g n3m 2012-2013
Miia vu Vy thugn Vy mupn Vy nghjch Vy sdm
Ti if vd trdi T i If h a t T i If thit trdi
(%) (%) (%)
7,81 7.70 7,80 7.40
12,65 12,42 12,79 12,81
79,54 79,88 79,41 79,79
TB 12,67
F CV (%)
79,65
Ghi chu: ns • khdc biil khdng y nghTa thdng ki a muc y nghTa 5%
3.3 Nang s u ^ t trdi t r e n cdy
Trpng lupng frung binh frdi va nang sudt Udi frin cdy giira cac miia vu khac biit cd y nghia tiidng k i d miic y nghia 5 % (Bang 3). Sd frai/cay vd ndng sudt frdi ti^n cdy vu nghich cao han vu tiiugn nhung frpng lupng tiimg binh Udi lai thdp hon. N h u vgy n h d cd ti Ii ra hoa cao nin nang suit vy n ^ j c h cao han vy tiiugn. 6 vu thugn cd s6 Udi/cdy it hon cac miia vy khac, mac dii cd frpng lupng Uung binli frai ldn hon nhung ndng sudt thdp han cdc miia vy khdc. Theo Tdn Thdi Trinh (1995), Udi xoai cat H6a Ldc cd u p n g lupng 350-500 g,
M u a vu Vu thuan Vu mupn Vu ngliich V u s d m
T r o n g luprng t r u n g b i n h t r d i ( g )
Nang suat 4 3 8 , P
4 1 3 , 9 ' 331,3*
367,4*'
7,9T 12^8^
101'
13,26^
F
C V ( % ) 6,26 32,0
Ghi chU: Trong ciing mpt cdt nhiing sd cd chir theo sau giong nhau khdc biel khong cd y nghTa thdng ke & mucy nghfa 5% qua phepjlniDunBanrns^lchdc biit Ididng f^
nghfa thdng ki a miic y nghia 5%, *. Khacbietcoy nghfa ihdng ki a mirc y nghfa 5%
3.4 P h a m c h a t t r a i
Tong sd chdt rdn hda tan (TSS), ham Iirgi^
vitamin C vd ham l u p n g chdt k h d frong tiiit trai^
khac bift giiia cac miia v y khdng cd ^ nghTa thot^;
k i (Bdng 4). N g h i i n ciiu quy trinh xfr ly hoa x t ^ cat H d a Lpc, Trdn V a n Hau (2013) cho rdng ip dyng quy frinh xii I^ ra hoa bdng P B Z k i t hpp vdi kich thich frd hoa bdng thioure khdng Idm anh hudng d i n m ^ t sd chi tiiu ddnh gia p h ^ chdt trii n h u ti l i tiiit frai, T S S , T A , vitamin C. Theo Tr^
Van Hau (2013), frdi xodi cdt H d a L d c cd t i n g « chdt rdn hda lan ( T S S ) t n m g binh Id 18,98%, han lupng vitamin C d giai d o a n 85 ngay S K D T tiuk binh la 6,88 mg/100 g tiiit frdi tuoi. |
Tgp chi Khoa hpc Tru&ng Dgi hpc Cdn Tha Ph&t B: Ndng nghiip, Thuy sdn vd Cdng nghi Sinh hgc: 35 (2014): 23-30
Bang 4: Hdm lumig Vitamin C, TSS vd chat khd thit trai xoai cdt Hda Ldc d nhung thdi vu khac nhau t^i huyin Cdi Be, tinh Tien Giang, nam 2012-2013 Muavu
Vu thugn Vy raugn Vy nghich Vusdm Trung binh F CV(%)
Tong so chSt H^m luong rdn hoa tan - Vitamin C TSS(%) (mg/100 g)
19,01 19,06 18,94 18,89 18,98 0,69
6,91 6,92 6,83 6,84 6,88 ns 0,65
lam Iirgmg chat lihd
(%)
19,05 19,01 19,07 19,03 19,04 ns 0,5 Ghi chii: ns: khdc biil khdngy nghia Ihdng ki & muc y nghfa 5%
3.5 Sau binh gdy hgi 3.5.1 Binh thdn thu
Binb than thu gdy hai cao vao giai doan phat hoa duac 2-3 cm cho din khi phat hoa phat triin hodn todn vd giai doan trai non nhiiu nhat d vu mudn, tiip theo Id vy nghjch (Hinh 5&6). Theo Lim va Khoo (1985) ndm Colletrotrichum gloeosporioides phat frien thich hop frong dieu kiin nhift dd tfr 25-32''C, ddi hdi phdi cd diiu kien dm dp cao di xam nhiem vdo ti bdo ciia ky chii, bao tu nay mam frong nude sau 6-7 gid. Do do, binh than thu phat triin mgnh frong miia mua la thdi diim cd nhift dd vd hm dp thich hpp cho bao tii phat triin gdy hm hoa, la va frdi non xoai.
f 30
Lin2 Si lin khao sit
Hinh 5: Ti li (%) phat hoa hi benh thdn thu dup'c khao sat d nhirng thdi vu khdc nhau tai huyin Cai Bi, tinh Tiin Giang, nam 2012-2013
Ldn 1: Tic khi hoa dugc khodng 2-3 cm, ldn 2: Khi hoa dugc 10 ngdy sau khi nd vd ldn 3: Khi hoa dgi kich thudc Idi da.
—•— Vu thupn —•— Vu nsipn •••A Vu r^Jijch —X Vy s6m
Hinh 6: Ti If (%) trdi b | b|nh than thu 6* nhirng thdi vu khac nhau trong nam tai huyin Cdi Be, tinh Ti^n Giang, nam 2012-2013
Ghi chU: Ldn 1: Thdi diem 10 ngdy sau khi dgu trdi, ldn 2: Thai diim 20 ngdy sau khi ddu trdi, ldn 3: Th&i diim 30 ngdy sau khi ddu trdi
Tap ChiKhoa hpc Tru&ngDai hge Cdn Tha Phdn B. Ndng nghiip, Thuy sdnvd Congnghi Sinh hpc: 35 (2014): 2^
3.5.2 Bo tri (Thrips sp.)
Ghi nhan sy gay hai cua sau benh frin cay xoai cho thdy bg UT la dich hai quan frgng anh huong din nang sudt cay xodi. Bo hi gay hai chu yeu frin phat hoa, ddc biit la giai doan dau frai lam cho frai non khdng phai friin dupe. Bp fri gay hai d hau hit
cac thdi vu frong nam,, ngoai trfr frong vu nghich % vu raudn mfrc dp gay hai tuong ddi thdp (Hinh"^
Theo Nguyin Thi Thu Cue va Ddng Chiin T h ^ (2003) till bp tri xudt hien liin tuc trong nam frinli non, bong va frai nhung xudt hien vdi mat s6 can va gay hai chu yeu frin :itm chinh vu (tir thang.].
3), liic khi hau khd va ndng nhat frong nam.
Hinh 7: Ti If (%) phat hoa hi bii lach gdy hai d nhirng thdi vu khdc nhau tgi huyin Cai Be, tinh Tien Giang, nam 2012-2013
Ldn 1 Khi hoa vira xudt hiin, ldn 2: Mgt vdi hoa n& trin phat hoa vd ldn 3: Hoa na rg vd co xudt hiin trdi non (trdi trimg cd)
gay hai hoa frong raua raua va bp fri d nhiing thang miia khd.
I KET LU4.N VA DE XUAT 4.1 Ket ludn
Xvr Iy ra hoa d bdn thdi vu frong ndm Id vy raiia, vy mudn, vu nghich va vy sdm co dnh hudng din ti If ra hoa, tdng sd hoa/phdt hoa, ti^ li hoa ludng tinh, ti If dau frai, frgng lupng trai, ndng sudt Uai/cay va sau benh gay hgi. Vu nghich cd ti li ra hoa, dgu frai cao nin dgt ndng sudt cao mac dii co ti li ryng Udi cao. Vu thudn ti le ra hoa thap do it dupe quan tdm, chii yeu la hinh thiic tang vu. Benh than thy gay hai phat hoa va frai nhiiu nhdt frong vy mudn va vu n^ich frong khi bi fri gdy hgi phat lioa giai doan ddu frdi frong miia khd, chu yiu d vu miia vd vy sdm.
4.2 De xuat
Cd thi dp dyng quy Ofrih xti Iy ra hoa ciia Trdn Vdn Hdu et al. (2011) bdng each xd ly PBZ vdi liiu lupng 1-2 g a.i./m duong kinh tdn, kfch thich frd hoa bdng thioure d ndng dp 0,3-0,5% sau 2,5- 3,0 tiidng di xu ly ra hoa rdi vy xodi cat Hda Ldc d Cai Be, Tiin Giang. Chu y phdng frir binh tiian tiiu
TAI LIEU THAM KHAO
1. Batten, D.J. and CA. Mc Conchie, 1995, Floral induction in growing buds of lyeh^
(Litchi chinensis) and mango (Mangifera' indica). Aust. J. Plant Physiol. 22: 783-791.
2. Chadha,K.L. 1993.Fruitdropinmai^o.Iii Advance in horticulture, Chadha, K.L. and | O.P. PareekEds. Vol.2 1131-1166. MalKotfi Publishing House New Delhi, India. | 3. Cue Trdng Trpt, 2013. Hiin trang vdgiSi'
phap phat friin san xudt, tiiu thu mdt s6 dl an frdi chu Iuc vimg Nam Bp. Hdi nghj san xudt rai vu mdt sd Ioai cay dn Uai chii luc d Nam Bd, td chfrc lai Tp. Bin Tre ngdy i 4/10/2013. Tr. 1-16.
4. Lira, T.K and K.C. Khoo, 1985. Diseases and disorders of mango in Malaysia.
Tropical Press SDN. BHD. Malaysia. 101 p
Top chi Khoa hpc Truong Dgi hpc Can Tha Ptidn B: Nong nghiip, Thuy sdn vd Cong nghi Sinh hpc: 35 (2014). 23-30
5. Hodng Huu Cuva Mai Van Tri, 2003. Hieu luc cua mpt sd loai thudc trfr ndm phdng benh than tiiu (Colletotrichum gloeosporioides) fren cay xodi (Mangifera indica h.) d mien Ddng Nam Bd. Kit qua nghiin ciiu khoa hpc cdng nghi rau qua 2001-2002. Nxb Ndng nghifp, fr. 347-354.
6. Nguyin Minh Chon, Phan Thi Bich frara va Nguyen Thu Thuy, 2005. Giao trinh tiiuc tap sinh hda. Tu sdch Trudng Dgi hpc Cdn Tho. tai lieu luu hdnh npi bd. 73 fr.
7. Nguyin Tht Thu Ciic vd Ddng Chiin Thdng, 2003. Bit lach gdy hgi xoai: Nguyen nhdn bdc phdt, thanh phan lodi, mdt so dgc diim sinh hgc, sinh tiiai va gdy hgi. TCKH DHCT, 2003, fr. 42-48.
8. Tdn That Trinh, 1995. Tim hiiu vi cac logi cay dn frai cd friin vgng xudt khau. Nxb.
Ndng nghiip. 278 fr.
9. Trdn Thi Tuc, Cao Anh Long, Phgm Van Cdn, Hoang Ngpc Thuan, Doan Thi Lu, 1998. Gido trinh cay an qua. Nxb. Ndng nghifp Ha Ndi.
10. Tran Vdn Hdu, 2005. Xac dinh mdt sd yiu Id anh hudng len su ra hoa xoai cat Hda Lpc. Lugn dn Tiin si Ndng hpc, Trudng Dai hpc Cdn Tho, 144 fr.
11. Trdn Vdn Hdu, Le Thi Thanh Thuy, Trdn Sy Hiiu, Chdu Ba Buih, Li Minh Qudc, Nguyin thanh Tdi, Nguyin Cdng Son, 20 i 1. Nang cao nang sudt xoai rai vu tgi hi^en Cao Lanh, tinh Ddng T h ^ . Bdo cdo de tai khoa hpc cap tinh. 146 fr.
12. Trdn Van Hau, 2013. Xu: ly ra hoa xoai cat Hda Ldc va cat Chu. Nxb. Ndng nghiip. 248 fr.
13.Vu Cdng Hau, 1996. Trdng cay an qua d Viet Nam. Nxb. Ndng nghifp TP. Hd Chi Minh. 488 fr.
14, Pham Thj Huong, Trdn Thi Tyc vd Nguyin Quang Thach, 2003. Cdy xoai va nhirng dieu can biel, Nxb. Ndng n^iep. Ha Ndi, 95 fr.
15. Phavaphutanon, L., K. Krisanapook, A.
Pichakum and K. Jutamanee, 2000. Changes of total non-structural carbohydrates within shoots of 'Nam Dok Mai' mango after PacIobuUazol application. Acta Hortic. 509, pp. 559-565.
