Kit qua nghign cdu khoa hpc BVTV-So 4/2012
/021106boduoiisim.htm, truy cgp ngfiy 30/8/2008.
4 Hoffman K.lvl., 1987. Earwigs (Dermaptera) of South Carolina, with a key to the Eastern North /\merican species and a checklist of the North /American fauna, Proc. Entomoi Soc. Vi/ash..
V o t . 8 9 . p p . M 4 .
5. Neiswander C R . , 1944. The Ring-legged earwig, Euboriela annulipes (Lucas)", Ohio Agricultural Experiment Station Bui, No.648,14pp.
6. Phgm Vfin L i m , 1999. K i t qug xfic djnh tfln khoa hgc ciia thifin djch thu d y g c trfin rau hg hoa thgp t y , Tgp chi Bio vi thwc v$t, 3:
27-29.
7. Charles A.T. and F J. Norman, 2005.
Order Dermaptera: Earwigs, Borror and Delong's Introduction to the study of Insect, 7"" Edition, Peter Marshall Publisher, USA, pp.234-238
8. Choate P.M., 2 0 0 1 . The order Dermaptera (Earwigs) in Florida and the United States (modified from Hoffman. 1987, http://entomoiogy .ifas.ufl.edu/choate/dermaptera.-pdf, truy cgp ngfiy 10/5/2009.
9. Ta Huy Thjnh, 2009. Danh lye cfic lofij thuflc bfl cfinh da (Insecta: Dermaptera) d Vigt Nam, Bio cio khoa hQC vd sinh thii vi tai nguyin sinh vit - Hdi nghi khoa hQC toin qudc lin thif 3, Hi Ndi ngiy 22/10/2009, NXB Ndng nghigp, Hfi Nfli, tr.342-369
10. Esaki Teiso and Ishii Tel, 1952.
Iconographia Insectorum Japoni-corum, Tokio Press, Japan.
NgSy nhin bii: 17. 5.2012 Phfin bign: TS. Oinh Vfin Oii-c
DAC B\tU SINH HOC CUA REP SAP M^M NAU COCCUS HESPERIDUM L.
(HOMOPTERA: COCCIDAE) GAY H^l TREN CA PHE CHE 6* SOU LA Biological Characteristics of Brown Soft Scale, Coccus hesperidum L.
(Homoptera: Coccidae), an Important Pest of Arabica Coffee in Son La Province
Sa Thl Phyang', VQ Quang Gigng^
A b s t r a c t
The brown soft scale. Coccus hesperidum L. (Homoptera: Coccidae) is an economically important insect pesl of Arabica coffee in Son La province. The biological characteristics of brown soft scale was investigated under laboratory conditions at Agricultural Department of Tay Bac University during 2009 - 2010. The life cycle of brown soft scale. Coccus hesperidum on coffee seedlings was 69.04 days at 25''C, 85% RH and 50.72 days at SO^C, 85% RH. Females can reproduce without mating. The bnawn soft scale has high fecundity. When reared on coffee, each female of brown soft scale Coccus hesperidum can lay 72 - 325 eggs and with high hatching rate (71.0% - 93.5%). Eggs hatched in 3 - 7 days after laid and the highest hatching rate was on the fourth day (43.39%).
The estimated threshold temperature for development was I L i e ^ C . The total effective temperature for completing a life cycle of Coccus hesperidum was 955.56°C. There were 3,72 generations per year.
Keywords: Brown soft scale. Coccus hesperidum L., coffee seedlings, Tay Bac University, the estimated threshold temperature for development, total of effective operating temperature.
DAT V A N D ^
Cfi phfi ehd Coffea arabica Ifi cfiy cflng nghigp
1. Tru'dng Cao DSng San La 2. Tru-dna Dai hoc Jiv B i c
chu lyc ciia tinh S a n La. D i n nfim 2009, dign tieh efi phfi chfi dgt 3.625 ha, san lygng dgt 4.456 t i n eg phfi nhfin (Cue Thflng kg San La, 2010). Mflt trong nhdng t r d ngai trong vigc san xuat cfi phg Ifi cfic lofii sfiu hai. Trong nhdng loai sfiu hai dfl, rgp sfip m i m nfiu Coccus
Kfit qua nghien c d u khoa hgc B V T V - S o 4/2012
hesperidum L. (Homoptera: Coccidae) la mflt trong nhdng dfli t y a n g gfiy hgi nguy h i l m trdn efi phfi ehe Coffea arabica d tinh San La. Ca l u trung vfi t r y d n g thfinh lofii rgp sfip m i m nfiu d i u chich hiit dich cfiy lfim cho cay cfi phe phfit t r i l n kem, lfi nhd gidn, qua nhd vfi ryng. Ngofii ra, khi dinh d y d n g , rgp sfip m i m nfiu dfi t i l t ra djch mgt, tgo d i l u kign cho Idp nam mufli den phfit triin va hgu qua Ifi Ifim giam qufi trinh quang hgp cua cfiy ea phe, dlin den giam nfing s u i t vfi ehat lyang san p h i m . Cho d i n nay, nhdng nghien cdu v l rgp sfip m i m nfiu d n y d c ta cdn rat hgn che. Bfii v i l t nfiy cung d p k i t qua nghidn edu v l dfic d i l m sinh hgc ciia rgp sfip m i m nfiu hgi cfiy ca phd chfi d San La.
PHU'ONG P H A P N G H I E N CO'U Thdi gian phfit dye efie pha, thdi gian vdng ddi, thdi gian sflng ciia t r y d n g thfinh eiia rgp sfip mem nfiu d y g c xfic djnh thflng qua nudi sinh hpc tgi phflng th( nghifim Bao vg t h y c vfit, Khoa Nflng Lfim Tru-dng Dgi hgc Tfiy B i c t d nam 2009 d i n 2010.
Thi nghigm nufli sinh hgc du-gc t i l n hfinh theo phyang phfip nufli efi t h l d 2 mde nhigt dfl (25°C va 30°C) trong ciing d i l u kign am dfl efl dinh (85%). Thdc fin Ifi cfiy ea phe con 12 thfing tufli So lygng efi t h l thl nghigm la 27-32 cfi t h l . Chgn nhi>ng trdng d y g c de trong 2 gid cua eung mflt ngfiy lfim ngufln vgt ligu nudi thi nghigm. Hfing ngfiy quan sfit thi nghigm, xfic dinh thdi gian Idt xac va cac tfip tinh sflng ciia rgp sfip m i m nfiu.
D l xfic dinh khg nfing de tni-ng ciJa rgp sfip m i m nfiu t i l n hanh thu thfip 20 doan canh ca phfi bfinh te dfii 20 cm bj nhiem rgp sfip m i m nfiu, mdi dogn ehi d l 1 efi t h l tat-dng thanh cai. Phia tren va phia dydi ciia cfinh cfich nai rgp sfip m i m nfiu djnh vj khoang 1 cm dfin 1 ldp bfing dinh 2 mfit quanh cfinh nhfim ngfin can l u trCing mdi n d bd di nai khfic Sau dd gifim cfinh vfio cfit am trong khay cfich ly. Theo ddi ngay 2 lan vfio 7 gid vfi 13 gid, d i m so au tning mdi n d phfin tfin khdi c a t h l tardng Uifinh cai vfi sfl trdng ung. Mfli thang thep ddi mdt dot, sfl cfi t h l theo ddi moi d g i n = 20.
Xfic djnh ty ig n d eua Ini-ng rgp sfip mem nfiu bing cfich thu thgp tn>ng rgp sfip m i m nfiu vda mdi dygc de ra (trong khoang 2 gid) chuyin vfio 10 dia petri cd Idt giay t h i m (20 tni-ng/dTa petri). DTa petn^cd tni-ng dygc dgt trong tu (^nh dn d nhigt dfl 25 C, am dfl 85%. Theo ddi t d thfing 3/2009 d i n thfing
11/2009, mdi thfing 1 lan. Theo ddi ty ig trdng nd (%) d cfic ngfiy sau khi trdng dygc de ra vfi ty Ig trdng nd (%) d cfic dgt theo ddi.
Nhigt dfl khdi d i l m phfit dye d y g c tinh theo edng thdc (to) = (nz.ta - ni.t,)/(n2 - n,). Trong dfl tl, tj Ifi nhigt dd nudi ti=25°C, t2=30°C; n,. nz la vdng ddi cua rgp sfip m i m nfiu khi nufii d 2 ngydng nhigt dfl t y a n g dng t,, iz Tflng tich fln hdu higu (K) du-gc tinh theo cflng thdc: K = ni(ti - to) hogc K = nz(t2 - to) (Phgm Binh Ouyln,1994). Sfl Ida ly thuylt trong mflt nfim (Y) d y g c tinh theo cdng thdc: Y = Q/K (Q Ifi tong tich dn ca nfim cho lofii rgp sfip m i m nfiu).
K E T QUA N G H I E N CO'U
1. T h d i gian phat t r i l n , v d n g d d i ciia rgp sap mem nau
Nudi d nhigt dfl 30°C vfi I m dfl 85%, thdi gian phfit t r i l n cua pha trdng t d 3 d i n 7 ngfiy, thdi gian phfit t r i l n cua au tning tufli 1 t d 6 den 11 ngay, thdi gian phfit t r i l n cua au tning tufli 2 t y 10 d i n 17 ngfiy, thdi gian phfit t r i l n cua au tning tuoi 3 t d 10 d i n 17 ngfiy vfi thdi gian t r y d c de trdng cCia tru-dng thanh t d 9 d i n 15 ngay. Nufli d nhiet dfl 25°C vfi am dfl 85%, thdi gian phfit t r i l n cua pha trdng t d 3 den 7 ngay, thdi gian phfit t n l n ciia liu trung tufli 1 t d 11 den 16 ngfiy, thdi gian phfit t r i l n cua l u triing tufli 2 t d 17 d i n 21 ngfiy, thdi gian phfit t n l n cua l u tning tufli 3 t d 17 den 20 ngfiy, thdi gian t r y d c de trdng eua tru-dng thanh t d 12 d i n 18 ngay (bang 1)
Thdi gian vflng ddi va ddi cua loai rgp sfip m i m nfiu khfi dai. Nudi d d i l u kign nhifit dfl 30°C, am do 85% thdc fin la cfiy efi phe chd, thdi gian vdng ddi trung binh 50,72 ngfiy (pham vi bien dflng Ifi 42 - 57 ngay). Nudi d d i l u kign nhigt dd 25°C, I m dg 85% thdi gian vdng ddi trung binh 69,04 ngfiy (phgm vi biln dflng lfi 64 - 72 ngay). Vdng ddi cua rgp sfip m i m nfiu nudi tren cfi phd chfi dfii han so vdi nudi trfin cam cua cfic nghien cdu khfic Theo Oleg Nicotic, Phgm Vfin L i m vfi cs. (2008). vdng ddi eua rgp sfip mem nfiu nufli tren cam d nhiet dd 30°C keo dfii t d 24,7 d i n 41,2 ngfiy. Trong khi dd, Bodenheimer (1951) cho rfing d nhigt dg 25°C vfi 30°C vdi thdc fin la cay cam, rgp sfip m i m nfiu hofin thfinh vdng ddi trong khoang thdi gian tyang dng ia 35 - 58,2 ngfiy vfi 24,7 - 41,2 ngay.
K4t qua nghifin ci>u khoa hpc
B i n g 1. Th6i glan p h i t triSn cua
Giai doan phdt tri^n Tru-ng
Au trunq tuAi 1 Au trung tuii 2 Au tnjnq tudi 3 Tru'dnq thinh trudc fffi tri>nq Vdnq 6&\
Tu6i Ihp cua trudnq thdnh D4i
BVTV-Sd 4/2012
r$p s i p m i m n i u (Sen La. 2009- 2010}
Thtn qian phit triSn (nqiv) 6" c i c di^u ki§n t°C=!30°C, RH = 85%
Phim vi bi6n d$ng 3 - 7 6 - 1 1 10-17 10-17 9 - 1 5 4 2 - 5 7
Trung binh 3,91 ± 0.32 8,28 ± 0,40 13.00 ±0,65
13.8 ±0.67 11.69 ±0,68 50.72 ±0,12
t°C = 26°C, RH = 85%
Pham vi biin dOnq 3 - 7 1 1 - 1 6 1 7 - 2 1 1 7 - 2 0 1 2 - 1 8 6 4 - 7 2 2 5 - 3 4 7 9 - 8 9
Trung binh 4.00 ±0,41 13,78 ±0,48 18,96 ±0,48 18,15 ±0,45 14,15 ±0.66 69,04 ± 0,82 30,15± 0,95 65.04 ±1,19
Ghi chu: Sd luvng ci thd nudi n, = 32; nz =27
2. Sinh sfin ciJa rgp sfip mim nfiu Khi nghifin cdu v l smh san ciia rgp sfip mim nfiu Coccus hesperidum Linnaeus hgi cfi phd chd d tinh San La nhgn thiy trong quin thl rgp sfip mim nfiu xufit hign tofin cfi thl trydng thfinh cfii, khdng thiy xult hign cfi thl trydng thfinh dye.
Nhu- vfiy, rgp sfip mim nfiu sinh san theo hinh thdc dan tinh de ra trdng, nghTa lfi trydng thfinh cfii khdng cin giao phfli nhyng trdng dygc d l ra v§n phfit triln binh thydng. Hinh thdc sinh san dan tinh ctia rgp sfip mim nfiu phii hgp vdi nhgn dinh ciia Nguyin Vilt Tiing (2008), Smith ef a/., (1997), Bodenheimer (1951).
Trydc khi de trdng, trydng thfinh cfii lofii rgp sfip mim nfiu da vgn dflng va tryc dgc eiia ca thl Igch vdi tryc eiia cfinh cfi phe (thdng thydng khi chya de trdng, true dgc cua ca thl trung vdi tryc cua cfinh cfi phfi). Phin byng cua rgp sfip mim nfiu thfing thydng fip sfit vdi cfinh efi phd, nhyng khi chuin bj dfi trdng phin bgng eua ehiing tfich khdi cfinh tgo thfinh 1 khe hd d l cho rgp sfip mim nfiu d l rfing de trdng. Trdng dyg-c dd thfinh fl dydi phgn byng trydng thfinh cfii, fl trdng ed sfip bgo vg.
Sau khi trdng nd mflt thdi gian khogng 1 ngfiy, l u tning rgp sfip mim nfiu mdi phgt tfin khdi fl trdng tim vj tri thich hgp d l djnh vj nai lay dmh dydng vfi gfiy hgi. Trong khogng thdi gian de trdng rgp sfip mim nfiu mg vin ily thdc fin d l nufli trdng trong ca t h l Vi vgy, sfl lygng va chit lyg-ng thdc fin cd anh hydng nhilu din sdc de trdng ciia rgp sfip mim nfiu.
Sdc dd trdng ciia rgp sfip mim nfiu hgi cfi phd chg rit cao, giao dflng td 72 den 325 trdng/cfii (bang 2).
Bdng 2. Sdc dd trdng cua tnpdng thdnh cdi r$p sap m i m niu (Son La, 2009)
Thing theo ddi
1/2009 2/2009 3/2009 4/2009 5/2009 6/2009 7/2009 8/2009 9/2009 10/2009 11/2009 12/2009
S6 tai-ng do tm (tn>n ll nhat
81 79 109 134 152 159 135 126 98 88 79 72
Nhieu nhit 172 187 273 289 265 311 325 231 257 199 184 168
yng thinh c i i d i p/cii)
Trung binh 123.36 ±14.19 127.75 ±14.78 167.40 ±19.10 198.75 ±23.13 208.85 ±17.66 208.85 ± 22.33 218.50 ± 22.73 187.80 ±13.66 174.90 ±20.91 147.05 ±14.89 130.35 ±11.09 106.35 ±13.46
Ghi chu:
d mdi thing
sd iu(;mg ci thd truimg thinh cii theo d6i n = 20
Vfio nhdng thfing thdi tilt khflng thugn Igi (am
dfl vfi nhigt dfl thip), kha nfing d l trdng cua
trydng thfinh cfii v5n khfi cao Thl dy, sfl lygng
trdng trung binh do trydng thfinh cfii dg dygc
trong cfic thfing 1, 2, 11 vfi 12 nfim 2009 tyang
dng Ifi 123,35; 127,75; 130,35 va 106,35
trdng/con cfii. Td thfing 5 din thfing 7 nfim 2009
Ifi thdi gian cfl dilu kign thdi tilt thugn igi eho
cfiy cfi phfi phfit triln, tgo nfin ngufln thdc fin dfli
dfio vfi chit lyg-ng cho rgp sfip mim nfiu. Kha
nfing de tn>ng cua rgp sfip mim nfiu trong dilu
kign nhy vgy dgt rat cao. Sfl lyang tn>ng trung
binh do trydng thfinh cfii d l ra trong thdi gian
Ket qua nghien c d u khoa hoc B V T V - S d 4/2012
nfiy b i l n ddng t d 208,85 den 218,50 trdng/cfii.
Trong khi dd, sdc de eua trydng thfinh cfii rgp sap mem nfiu hgi tren cam tai Palestine ehi t d 8 d i n 210 trdng/con cfii (Bodenheimer, 1951).
3. Ty le n d ciia tru>ng rgp sap mfim nfiu Khdng phai tat ca cfic trdng d y a c de ra d i u nd thanh au triing. Sfl lu-gng trdng n d d cfic ngfiy sau de cd s y khfic nhau rd rgt. Thl nghigm theo ddi kha nfing n d ciia trdng rgp sfip m i m nfiu trong 9 dot nudi, mfli dgt 200 tni-ng d y g c t i l n hfinh trang phdng thi nghigm d dieu kign 25°C, I m dfl 85%. K i t qua cho t h i y tni'ng n d bfit d i u t d ngfiy thd 3 sau de, k i t thiic n d vfio ngfiy thd 7 sau de (bang 3). Sfl tning nd tfip trung chii y l u d ngfiy thd 3 vfi thd 4 sau de Ty lg trdng n d cao n h i t vfio ngay thd 4 sau de vdl sfl lu-gng trdng nd trung binh la 86,78 trdng, dat 43,39% tflng sfl trdng theo ddi. Chi tidu nfiy d ngay t h d 3 sau dd dat thap hon va Ifi 41,78 trdng (dgt 20,89% tflng sfl trdng theo ddi). Sfl lygng trdng n d trung binh giam dan t d ngay t h d 5 sau de vfi den ngfiy thd 7 sau de chi dat trung binh 3,56 trdng, t y a n g dyang 1,78% tflng sfl trdng theo ddi.
Bang 3. Ty If trdng nd qua cac ngay sau de cua r$p sap m i m nau (Son La, 2009)
Bang 4. J^ Ig nd- cua trdng r$p sdp m i m nau 6- cac thdng (SoTi La, 2009)
Ngay sau de Nqay thij. 3 l^qay thi> 4 Nqiy thl> 5 Nqay thir 6 Nqay thu' 7
So trung no trunq binh
41,78°
86,78"
26.22=
9,78"
3,56* . LSD = 5,90
Ty le no so tonq s6 (%) 20.89 43,39 13,11 4,89 1,78
Ghi chu: Nuoi 9 dot, moi dgt theo ddi n = 200 tning; fc = 2^C, RH = 85%
Trong pham vi cung mgt cgt, cac gii tf] mang cSc chO' cai khac nhau chi sw sal khac co ^ nghTa a muc xac suatP<0,05.
K i t qua theo doi ty ig n d cua trdng rgp sfip mem nfiu t d thfing 3 den thfing 11/2009 trong dieu kign phong thi nghigm cho thay ty Ig trdng nd cfic thang trong nfim khflng giong ntiau.
Trong thang 10-11/2009, ty lg nd eiJa trdng rfip sap m i m nfiu dat thap nhat, chi la 71,0 - 75,0%.
Ty 16 nd ciia trdng trong thang 7-8/2009 dat cao nhit vfi la 92,0 - 93,5% (bang 4).
iDgrl theo dor Thinq 3/2009 Thinq 4/2009 Thinq 5/2009 Thinq 6/2009 Thing 7/2009 Thinq 8/2009 Thinq 9/2009 Thinq 10/2009 Thinq 11/2009
So trunq nt^/dTa 16,50 ±0.97 17,60 ±0,77 17,30 ±0,76 17,10 ±0,63 18,70 ±1,07 18,40 ±0,50 16,50 ±1,32 14,20 ±1,65 15,00 ±1,39
Ty le no (%) 82,5 88,0 86,5 85,5 93,5 92,0 82.5 71.0 75,0 Ghi chO: M5i dgi theo ddi 10 lin nhic l^i, mdi lin nhic l^i 20 trimg,
Diiu ki$n thi nghiem- fC = 2^C. RH = 85%
Cfl s y chfinh Igch v l ty Ig nd cua trdng rgp sfip m i m nfiu d cfic thfing trong nam cd the do nhieu y l u tfl nhy nhigl dfl, I m dfl, finh sfing, thdc fin. Theo ehiing tfli, trong cfic y i u tfl dfl, y l u tfl thdc fin cd anh hydng tryc t i l p d i n s y phfit triln ciia tru-dng thfinh cfii, t d dfl anh hydng tryc t i l p d i n s y hinh thanh, phat t r i l n va ty Ig n d cua triing. Nhii-ng thang eufli nfim (thfing 10-11/2009) efl thdi t i l t khfl, lanh, cfiy ca phd can cfli, ngufln thdc fin cho rgp sap m i m nfiu bi han che Dieu nfiy da anh hydng x i u d i n s y hinh thanh trdng trong ca the tru-dng thanh cfii. Vi vgy, nhdng trdng d y g c de trong thfing 10-11/2009 efl ty Ig n d thap. T d thang 3 trd di, dieu kign thdi t i l t thugn Igi cho cfiy ca phd sinh trydng phat t n l n , tgo ra nguon thdc fin phong phii cho rgp sfip m i m nfiu phfit tnen vfi hinh thanh trdng, dfin d i n ty Id trdng n d tfing len.
4. Ngyo'ng nhiet d o k h d i d i l m phat due va sfl t h l hg trong nam
T d k i t qua nudi vdng ddi cua loai rgp sfip m i m nfiu d 2 mdc nhigt dfl ifi 25°C va 30°C, am dfl 85% (bang 1) dfi tinh d y g c nhigt dfl khdi d i l m phfit dye to = (n2.t2 - niti):(nz - n,) = (25 x 69,04 - 30 x 50,72):( 25 - 30) = 11,16''C. Trong khi dfl, ngydng nhifit dfl khdi d i l m phfit due eua rgp sfip m i m nfiu nudi trdn cam d Palestine la 13,0°C (Bodenheimer, 1951).
Tflng tich fln hdu higu d l rgp sap m i m nfiu hoan thfinh vflng ddi K = ni(ti - to) = 50,72 x (30 - 11.16) = 955,56''C. Tflng tieh fln hdu hifiu (Q) d l eho rgp sfip mem nfiu trong 1 nam tgi San La
Tflng hg-p B V T V - S f l 4/2012
Ifi 3551,53°C. Sfl Ida ly t h u y l t (Y) ciia rgp sfip m i m nfiu trgn cfi phfl tgi San La lfi Y = Q/ K = 3551,53 : 955,56 = 3,72 Ida. Trong thyc t l , rgp sfip m i m nfiu hai trfin cfi phfi ehd d San La cfl hign tyg-ng gfli Ida vi t r y d n g thfinh ctia lofii rgp sfip m i m nfiu nfiy cfl tufli thg vfi thdi glan d l trdng ciia trydng thfinh cfii dfii K i t q u i tInh sfl Ida ly t h u y l t d dfiy g i n t y a n g t y n h y nhgn xfit ciia Smith ef al. (1997). Theo cfic tfic gifi nfiy, rgp sfip m i m nfiu hgi trfin cam d Queensland cd 4 - 5 ida/nSm, d New South Wales, Victoria cd 3 - 4 Ida/nfim vfi d phia Tfiy Australia cd 2 - 3 Ida/nfim.
K E T LUAN
Nudi trdn cfiy cfi phfi con d hai d i l u kign fln djnh v l nhigt dfl vfi I m dfl (25°C, 85% I m dfl vfi 30°C, 85% I m dfl), vflng ddi cua rgp sfip m i m nfiu trung binh tyang dng Ifi 69,04 vfi 50,72 ngfiy.
Rgp sfip m i m nfiu cfl sdc dfi trdng cao (72 - 325 trdng/cfii) vdi ty lg trdng n d eOng cao ( 7 1 % - 93%). Trdng n d t d ngfiy t h d 3 d i n ngfiy t h d 7 sau de, ty Ig trdng n d cao n h i t vfio ngfiy t h d 4 sau dg (dgt 43,39 % tflng sfl trdng)
Nhigt dfl khdi d i l m phfit dye cua rgp sfip m i m nfiu nufli trfin cfiy cfi phg chg lfi 11,16 °C; tflng tich dn hdu higu Ifi 955,56 (dfl/ngay). Trong mflt nfim, v l 1^ thuylt, rgp sfip m i m nfiu ed t h l hofin
thfinh dyg-e 3,72 Ida trgn cfiy cfi phd chfi d d i l u kign San La.
T A I L i e u THAM K H A O 1. Bodenheimer F.S., 1951. The brown soft scales {Coccus hesperidum L.). Citrus entomology in the Middle East. Uitgeverlj. p. 354-363.
2. Cyc thdng kfi tfnh S a n La, 2010. Niin glim thdng ki tfnh San La 2009. Nxb Thflng kfi Hfi Nfli, 287 trang.
3. Oleg Nicetc, Phgm Vfin L i m , Ngfl T i l n DQng vfi Dinh Vfin Ddc, 2008. Siu binh hai phd bidn vi thiin djch trin ciy Sn qui c6 mOL Nhfi xult bfin Nflng nghigp Hfi Nfli, tr 4 0 ^ 1 .
4. Phgm Binh Q u y l n , 1994. Sinh thii hQC cdn triing, Nxb Gifio dye.
5. Smith Dan, Beattie G. A. P., and Broadley R. H., 1997. Citrus pests and their natural enemies, Queensland Depatment of Primary Inductrles, GPO box 46 Brisbane, Q 4001, Australia, pp. 43 - 45.
6. Hguy^n VikJOng, 200B. NhOng didu k^ la vd sinh sin & cdn triing. Nxb Khoa hgc ky thugt tr. 13.
Ngiy nhin bii: 21.5.2012 Phan bign: GS.TS. Phgm Vfin Lam
DANH GIA Ml>C BQ NHI^M MOT S6 SAU BENH C H O Y ^ U TREN CAC GidNG LUA C H O Ll^C 6 PHIA BAC
Cyc Bgo vg thyc vgt 1. Tinh hinh phfit sinh gSy hgi ciia mflt s f l dfli t u y n g djch h^i trgn liia ir cfic tinh phia Bdc
Cho d i n thdi d i l m cufli thfing 4.2012, d m i l n Bfie cfl trfin 9 0 % dign tich liia d y g c trflng cfic giflng mdi cfl ngufln gflc t d Trung Quflc, chii y l u Ifi nhiflm giflng liia lai vfi ICia t h u i n c h i t l y g n g cao, thich dng rflng. H i u h i t nhdng giflng nfiy d i u nhiem cfic dfli t y g n g d|ch hgi quan trgng nhy r l y nfiu, cufln Ifi nhd, bgnh dgo fln... ciing vigc Igm dyng phfin dgm vfi y l u tfl c y c doan cua thdi tilt, ndn trong nhdng nfim g i n dfiy dign tich vfi mdc dfl n h i l m djch hgi trgn Itia cfl xu t h l tfing cao, dgc bigt lg r l y nfiu, r l y lyng t r i n g vfi s3u
cufln Ifi nhd. Mflt sfl dfli t y a n g djch hgi mdj phfit sinh, cfl nguy c a hgi ngng n h y r i y nfiu nhd x u l t hign t d Oflng Xufin 2009 d n h i l u tinh; nhgn gig cd xu h y d n g ngfiy cfing tfing trong nhdng nfim g i n dfiy; vy Hfi Thu 2009 x u l t hign bgnh lun sgc den; Bgnh vfing Ifi tgm thdi (Rice Yellow Stunt Virus) tfii x u l t hign n h i l u i^a p h y a n g .
Tuy nfing s u i t , san lyg-ng liia lien tyc tfing qua cfic nfim n h d cd bfl giflng cfl t i l m nfing nfing s u i t , nhyng chi phi phdng t r d djch hgi cOng tfing Ifin, anh h y d n g d i n higu qu5 san x u l t liia, dflng thdi hfla c h i t bao v g t h y c vgt s d dyng nhilu eOng finh h y d n g xau d i n mfli t r y d n g .
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