KHOA Hpc CdNO NOHt
AIXIH HUOIXIG CLIA C H E SAIXIG V A PHAIXI D A M a£lXI T Y L t SdlXIG V A SIIXIH TRUOIXIG C U A C A Y M U I X I
(DiaSPYRaS MU!\f JK.ZH1E\/.EX L E C O M T E ) O G I A I DOAIXl VUOIXI U O M
D6 Anh Thin' T6MTAT
Cay Mun {Diospyros mun A.Chev. ex Lecomte) Ii mpt loai cky gb quy hi^m co gia tri kinh t^ va bao ton cao 6 Vi$t Nam. Nghifin ciiu nay danh gia anh huong cua vific che sang va bon phan dam ddi vdi ty Ifi sdng va sinh tnrong loai c4y nay 6 giai doan vuon nam. Thi nghiem duoc theo d6i trong 6 thing va dupc bd tri theo ki^u 16 chinh. 16 phu (split-plot design) voi 3 ldn lap cho 2 nhan td la che sing (voi 4 miic: ddi cbiing, che 25%, che 50% va che 75%) va phan dam (voi 4 miic nong do: ddi chiing, 0,1%, 0,3% vi 0,5%). K^t qui cho thay cay Mun b giai doan vuon uom co ty 16 sdng khi cao va sinh tnwng khi nhanh. Sau 6 thing ty lfi sdng cao nhat dat xdp xl 90%; Do, H va sd la/ciy trung binh la 4,7 mm, 48,8 cm va 24 li/cay. Nhin td che sing c6 anh huong ro rfit d^n ty lfi sdng va cac chi tifiu sinh truong so voi cong thiic ddi chiing. Trong d6, miic che sang 50% la c6ng thtic che sang tdt nhat, Aky la miic che sang cho ty lfi sdng thupc nhom cao nhdt vi cic gii tri sinh tmong vfi Do. H va sd la/cay tot nhdt. Nhan td phan dam khong co anh huong ro rfit dfin ty lfi sdng, nhung CO anh huong d^n sinh trudng cua cay Mun. N6ng dp bon dam phii hop voi cay Mun bifin ddi theo giai doan tudi. Trong giai doan 2 thing tudi ndng dp thich hcrp la 0.1% • 0.3%. con den den giai doan 4 va 6 thang tudi thi nong dp thich hgp la 0,5%.
Tii khda: Ciy Mun. chesang, dam, sinh tnrdng, tyl$sdng.
I.DATVAND^
Mun hay con gip la Mun siing {Diospyros mun AChev. ex Lecomte) thupc hp Thi (Ebenaceae), li loii cay go trung binh. mi sang, mpe cham. Tai Viet Nam, da phit hien Mun co phan bd tir nhien 6 Hi Giang, Lang Son, Tuyfin Quang, Hoa Binh, Hi Tinh, Quang Binh, Khinh Hoa, Nmh Thuan. G6 Mun c6 mau den bong, ciing vi bdn thuong diing lim dua vi dd thii cong my nghfi cao cap (Pham Hoing Hd, 1993). Do go Mun thupc loai go quy, cd gia tri kinh t^ rat cao nfin cic qudn th^
mpe tu nhifin ctia Mun dang hi suy giim nhanh chong do bj sSn lung vi khai thic kifit Hon niia do khan hiem ve cay me gieo gidng nfin frong tu nhifin so luong cay tai sinh con rat it vi vay nguy ca bi^n mdt loai ciy quy hi^m nay cr nuoc ta la rat cao. Hifin Mun duoc phan loai vio nhom loai quy hi^m cdn bao vfi a miic dp de dpa bac V frong sich do Vifit Nam (2007) vi cr mtic ctrc ky nguy cap (CE Alcd) frong danh muc dd cua lUCN (2013). Vi the vific tao cay gidng Mun co vai frd quan frpng frong vific bao ton vi phat trien loai ciy niy.
Trong tao gidng ciy rimg, ky thu^t chim sdc cay con a giai doan virdn uom co inh hirong quy^t dinh
' Tnrimg D^i hpc LSm nghi?p
d^n ty lfi sdng vi chat luong ciy con. Trong do ch^
dp che sing vi bon phan dupc coi li 2 bi$n phip ky thuat quan frpng (Volenec & Cunnmgham, 2005;
Thimothy et al., 2012). Tuy nhifin, hifin con thi^u vdng cic cong trinh nghifin ciiu v^ ky thuit gieo uom loii ciy Mun. Vi vay nghifin ctiu anh huong ciia vific che sing vi bon dam doi voi ciy Mun a giai doan vucm uom sfi gop phan hoan thi^n ky thuit gieo uom tao ciy gidng phijc vu cho cong tic bao ton vi phat tri^n loii ciy quy hidm nay 6 Vifit Nam.
Z. VAT LJ£U VA PHUDNG PHAP NGHfiU CUU
2.1.V^tli^u
Hat Mun sau khi nay mdn (khoang 1 tuan) khi vi mam dat 1,2-1,5 cm thi dupc ciy tn;c tidp vao bdu nuoi ciy. Bau c6 kich thuoc (17 cm vd dudng kinh
*24 cm vd chidu cao), khdi lupng m6i bdu khoang 1,40 kg vdi thinh phdn rupt bau theo ty 1^ vd thd tich gom dat den c6 kdt von (90%), phin chudng hoai (5%), xa dira vi fro frau (2,5%). Vit U^u che sing li lucri che vi phan bon la phan dam urfi ((NH2)2CO) pha o dang dung dich vcri cic mtic ndng do 0,1%, 0,3%, vi 0,5% dd hrdi phun cho ciy. Thi nghidm dugc tidn hinh tu thing 11 nim 2011 ddn thing 5 nam 2012 tai ca s* 2 ctia trudng Dai hpc Lim nghi$p b Dong Nai.
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2.2. Phuong p h ^ nghifin cihi
Thi nghidm dupc thidt kd theo kidu 16 chinh. Id phu (^lit-plot design) vdi 3 lan lip. Trong dd, trong moi khdi (1 ldn lap) bd tri 4 16 chinh tuong ting voi 4 mtic che sing: khdng che/ ddi chting (ky hifiu l i AO), che 25% (Al), che 50% CA2) va che 75 (A3). Trong mdi 16 chinh lai bd tri 04 16 phu iing vdi 4 mtic bdn dam:
ddi chting/khdng bon (ki hifiu li NO), ndng do 0,1%
(Nl). ndng dp 0,3% (N2) v i nong dp 0.5% (N3) (bing 1). Tong cpng thi nghifim c6 16 c6ng thtic (4 cong thtic che sing x 4 cong thtic bdn phin) vdi 3 lan lip.
M6i c6ng dnic iing voi 1 6 thi nghidm, sd lupng cay frfin mdi 6 thi nghifim la 49. Tdng sd cay thi nghifim l i 2352 ciy (16c6ng thiic* 3 ldn lap * 49 cdy/d).
Bang 1. So dd b6 tri thi nKhi^m che sing vi hba dam Kh6il
AO NO Nl N2 N3
A2 Nl N3 N2 NO
Al N3 N l NO N2
A3 NO N2 N3 N l
Khoi II Al
N3 NO N2 N l
AO N2 N3 N l NO
A2 N l N2 NO N3
A3 N3 NO Nl N2
Kh6i III Al
NO N2 N l N3
A3 N3 N2 NO N l
AO N l N3 NO N2
A2 N2 NO N l N3 Vi$c tudi bon d?m thuc hifin khi ciy con dupc 1
thing tudi, sau do dinh ky tudi bon 2 tuan 1 ldn cho ddn het 6 thing. Tdng sd lan bon l i 11 lan, mdi ldn m6i 6 thi nghidm dupc tudi bdn 2 lit dung dich dam pha theo cic nong dp xic djnh vio budi chidu. Lupng phdn dam cho moi ldn bdn la 216 g, bao gom 24 g cho cic 6 thi nghidm cd bdn dam d nong do 0,1% (1 g/lit * 2 lit/6 * 4 miic che sing * 3 ldn lap), 72 g cho cic 6 thi nghidm cd bdn dam a nong do 0,3% (3 g/lit
* 2 lit/6 * 4 miic che sing * 3 lan lap) v i 120 g cho cic 6 thi nghidm cd bdn dam b nong do 0,5% (5 g/lit/6 * 2 Ut/ldn * 4 mtic che sing * 3 ldn lip). Cic bidn phip chim sdc khic nhu lim cd, tudi nudc, phdng trir sau bdnh dupc i p dung gidng nhau d tdt ca cic cong tiitic thi nghidm.
Thi nghidm dupc bd tri 1 lan va dupc theo ddi ddn hdt 6 thing. Cic chi tifiu vd ty Ifi sdng (%), dudng kinh cd rfi Do (mm), chidu cao viit ngpn H (cm) va sd li/ciy dtrpc do ddm djnh ky 2 thing 1 ldn d c i c giai do^n hioi 2 thing, 4 thing v i 6 thing cho timg cdng thiic. Sd lidu tiiu th^p duoc xii ly theo phtrong phip phin tich phuang sai nhdm xac djnh sir i n h hirdng ciia nhin td thi nghifim ddn c i c chi tifiu didu tra. Tifiu chudn Duncan dupc sii dting dd phdn c i c gii tri Clia cic chi tifiu didu fra thinh cic nhom nhim li^a chpn cdng thtic thi nghidm hoic nhdm cdng thtic thi nghidm tdt nhdt
8.K^QUAVATHAOLUAN
3.1. Anh hudng cua che sing v i bdn d^m ddn ty Id sdng cua ciy Mtm
Bang 2 cho thay sd ciy Mun cdn sdng sau 6 thing d cic cdng thiic thi nghifim dao ddng k h i ldn, thap nhdt li 94 ciy (63,9%) d cdng thtic ddi chting, khdng che vi khdng bdn dam (AONO) ddn cao nhdt l i 136 cdy (92,5%) d cdng tiuic che bdng 75% v i phin damO,5%(A3N3).
Xfit tiieo timg nhan td thi nghidm, d cic cong thtic che sing khic nhau ty Id sdng cOa ciy Mun cd sir khic bidt rd rdt, thap nhat d cdng thiic ddi chting (AO) vdi ty Id chi dat 64,3%. Trong khi dd d cong tiuic che sing 75% (A3) ty lfi niy dat tdi 89,3%, sau dd ddn 87,6% va 86,6% d cdng thiic che sing 25% (Al) v i cdng thiic che sing 50% (A2). Cic gii tri niy gdn bdng 1.4 ldn so d vdi cdng thtic ddi chting. Kdt q u i phan tich phuang sai (p„ = 1,068*10^ < 0,05) v i tifiu chualn Duncan (p > 0,05) cho thdy miic dp che sang anh hudng rd rfit ddn ty lfi sdng, nhtmg khdng cd su khic bidt rd rdt vd ty Id niy giira 3 cdng thiic che sing Al, A2 v i A3. Ddi vdi anh hudng cua vide bdn dam v i inh hudng tong hop ciia c i hai nhin td ehe sing*bdn dam, kdt qua phin tich thdng kfi cho thdy cie nhdn td niy khdng cd i n h hudng rd rdt ddn ty Id sdng sau 6 tiling chim sde b vudn uam (p^ - 0,673 v i P asM = 0.527, ddu > 0,05). Nhu viy frong giai doan 6 thing tudi d vudn uom vifie che sing cd anh hudng ldn ddn ty Id sdng ciia cay Mun, tuy nhifin vide bdn dam vdi miic ndng dO tir 0,1% ddn 0,3% khdng cd i n h hudng rd rdt ddn tJ Id niy.
N O N G NGHISP V A PHAT TRI^N NdNG T H O N - Kt 1 - THANG 9/2013 103
KHOA H9C CdNO MOHt
Bang 2 i y le s^ng ciia cSy Mim o cac cdng thuc thi nghidm che s^ng v i b6n dam sau 6 Ihdng
Cong thiic Cong
thtre che sang
AO (doi chting) Al (che 25%) A2 (che 50%) A3 (che 75%) So cay song TB Tyle sdng TB(%)
Cone thiic bon dam NO (d6l chiing)
94 123 125 135 119,3 81,1
Nl (0,1%) 96 125 127 127 118,8
80,8
N2 (0,3%) 99 132 134 127 123,0 83,7
N3 (0,5%) 89 135 123 136 120,8 82,1
Sdcay s6ngTB 94,5 128.8 127.3 131.3
6vii6niiom T^I^ TB
64,3 87,6 86,6 89,3
3.2. Anh hudng che sing vi bdn d?un ddn smh (H) vi sd li/cay ctia ciy Mun d cic giai doan 2, 4 vi trudng ctia ciy Mun 6 thing tudi frong vudn uam d cic cdng thtic thi Ket qua tong hpp gii tri frung binh ctia cic chi nghidm vd che sing vi bdn dam dupc trinh biy a tifiu vd dudng kinh cd rfi (Do), ehieu cao viit ngon bang 3.
Bing 3. Smh trudng dudng kinh cd vi, chidu cao viit ngpn vi sd Ii trung binh/ciy cua ciy Mun dr giai doan 2, 4 vi 6 thing tudi dr cic cdng thiic thi nghidm
Cong thiic TN AONO AONl A0N2 A0N3 AINO AlNl A1N2 A1N3 A2N0 A2N1 A2N2 A2N3 A3N0 A3N1 A3N2 A3N3
n (ciy)
94 96 99 89 123 125 132 135 125 127 134 123 135 127 127 136 TB
Giai doan 2 thang tuoi Do
(mm) 1,5 1,5 1,4 1,5 1,7 1,7 1,7 1,7 1,6 1,7 1,7 1,7 1,6 1,6 1,6 1,7 1,6
H (cm) 10,5 10,4 10,0 10,5 13,9 15,1 14,8 15,0 13,8 14,8 15,0 14,9 13,8 13,8 14,4 14,3 13,4
So IVciy
4,2 4,1 4,0 4,1 4,2 5,2 4,5 4,4 4,7 4,5 4,5 4,5 4,6 4,8 4,8 4,6 4,5
Giai doan 4 t h ^ g tu6i Do
(mm) 2,7 2,8 2,8 2,8 3,2 3,0 3,2 3,2 3,1 3,4 3,4 3,6 2,8 2,9 2,9 3,0 3,1
H (cm)
26,0 27,0 28,4 28,7 30,8 30,6 32,4 32,0 31,7 35,2 34,6 36,2 27,6 28,0 28,5 29,6 30,5
So la/cay
12,0 12,8 12,8 12,4 13,5 13,0 13,4 12,5 13,4 15,1 14,3 15,6 12,8 11,8 12,1 12,7 13,1
Giai doan 6 t h ^ g tuoi Do
(mm) 4,5 4,4 4,5 4,8 5,0 4,9 5,1 5,1 4,9 5,0 5,1 5,3 4,0 4,1 4,2 4,3 4,7
H (cm) 43,4 43,4 45,4 46,1 50,1 51,8 52,9 52,9 52,1 55,8 55,6 56,1 42,1 43,9 44,4 44,2 48,8
S6 Id/cay
20,6 21,4 21,0 22,2 27,5 25,6 26,8 26,6 27,4 28,9 29,6 30,1 19,0 18,1 19,0 19,9 24,0
3.2.1. Giai doan 2 thing tudi
Bang 3 cho thay, d giai doan 2 thing tuoi gii tri Do bien ddng tir 1,4 mm den 1,7 mm, trung binh la 1,6 mm. H bidn dpng tir 10,0 cm den 15.1 cm. trung binh li 13.4 cm va sd li /cay dao dpng tir 4,0 li ddn 5,2 la, trung binh li 4,5 li.
Kdt qua phin tich phuong sai hai nhan to cho thay nhan td ehe sing cd inh hudng rd rdt den chi tidu Do vdi miic y nghia 95% (p^ < 0,05). Tlieo tifiu chuan Duncan Do dupc lim 3 nhdm, frong dd nhdm cd Do cao nhdt (1,66 nun vi 1,65 mm) ting vdi cic cdng thtic che sing Al va A2, va nhdm cd Do thap
nhdt (1,48 mm) iing vdi cdng thtic ddi chiing (AO).
Trong khi dd inh hudng ctia phin dam vi anh hudng tdng hpp ciia che bdng*phin dam ddn Do li khdng cd y nghla vd m$t thdng kd (pd= 0,443 > 0,005 vi p«,.d
= 0.059 > 0,05).
Doi vdi chi tifiu H, cic nhan td che sing, phdn dam vi nhin td tdng hpp che bdng*phan dam ddu cd inh hudng rd rfit ddn chi tifiu niy (p„ = 0,000, pa = 0,000 vi p„.d = 0,000, ddu < 0,05). Ddi vdi nhdn td che sing, eic gia tq H dupc chia lim 3 nhdm, nhdm H dat gii fri cao nhat (14,7 cm vi 14,6 cm) tirong ling vdi nhdm cdng tinie che sing Al va A2, gdp gdn 1,5
104 NONG NGHIEP VA PHAT TRIIN N O N G T H O N - KY 1 - THANG 9/2013
KHOA HOC C O N O N 0 H £
ldn so vdi gii tri H t h ^ nhdt (10,35 cm) d cdng tiitic ddi chiing. Ddi vdi nhin ^ phin dam, sinh trudng H dupc chia thinh 2 nhdm khic bifit nhdm cd gii h i H cao 13,5 cm, 13,6 cm v i 13,7 cm ting vdi c i c cdng thiic Nl. N2 v i N3, v i nhdm cd g i i tri t h ^ l i 13,0 cm ling vdi cdng tiiiic ddi chting (NO). Ddi vdi nhan td tdng hpp che sing*phan dam, H dupc ehia lim 4 nhdm khic bifit frong dd nhdm thdp nhat cd gii tri tu 9,95 cm ddn 10,48 em (ting vdi cic td hpp ciia cdng thtic khdng che sing vdi e i c miic bdn dam khic nhau: AONO. AONl, A0N2 v i A0N3 v i nhdm ed gii til cao nhdt dat gii fri tir 14,77 cm (d cdng tiuic A2N3) ddn 15,13 cm (d cdng thtic A2N1). Tuy nhifin giira cic cdng thiic cho sinh trudng H cao nhdt niy khdng c6 su khic bifit vd mat thdng kfi theo tifiu chudn Duncan ( p ^ . j ^ = 0,31 > 0,05).
Ddi vdi chi tifiu sd li/ciy, tirong tu nhu vdi chi tifiu H, c i 3 nhdn td che sing, phin dam v i che bdng*phdn dam ddu cd inh hudng rd rfit ddn chi tifiu niy. Dudi cic mtic che sing khic nhau, sd li/cay tmng binh dupc chia lim 2 nhdm, nhdm cd gia tri cao (4.6 li, 4,6 l i v i 4.7 li) d c i e edng thtic cd che sdng ^ 1 , A2, A3) ldn hon hdn g i i tii 4,1 li d cdng thtic ddi chting (AO). Ddi vdi cic nhin td phdn dam vi nhin td tdng hpp che sing* phin dam, chi tifiu niy dat gii hi cao nhdt l i 4,7 l i / c i y v i 5,2 l i / c i y tuong ling d cdng thtic bdn dam N l v i d cdng thtic tdng hpp A2N1.
Nhu viy cd thd thdy, d giai doan 2 thing tuoi ca 3 chi tifiu Do, H v i sd l i / c i y d cic cdng tiitic cd che sing vi bdn dam ddu ldn h i n cie g i i tri d cie edng thtic ddi chting. Trong dd, sinh tiudng ciia Do va H tdt nhat d nhdm cic cdng thtic Al (che 25%) v i che A2 (che 50%). Nhin td phin dam khdng i n h hudng rd rdt doi vdi chi tifiu Do, nhtmg 1^ rd rdt vd mit thdng kd ddi vdi chi tifiu H v i sd l i / c i y . Sd li/cay dat cao nhdt b edng tiiiie bdn dam N l (ndng dp 0,1%), tuy nhifin chua cd si^ khic bifit rd rfit ve H giiia cic cdng thiie cd bdn dam. Nhan to tdng hop che 8ing*phin dam khdng cd i n h hudng rd rdt ddi vdi chi tifiu Do nhung ed inh hudng rd rfit ddi vdi chi tifiu H v i sd li/ciy.
3.2.2. Giai do^ 4 thing tudi
O giai doan 4 thing tudi g i i tii trung binh ciia Do li 3,1 mm, cdn g i i trj trung binh ciia H v i sd li/ciy ldn lupt l i 30,5 cm v i 13,1 li. So vdi giai doan 2 thing tudi tri sd Do d giai doan niy gdn gdp ddi, Irong khi dd H g ^ hem 2 Idn, cdn sd l i / c i y gdp xdp
xi 3 lan (bing 3). Trong giai doan niy, cic nhan td che sing, phan dam v i nhin td tdng hpp che sing*phin dam ddu ed i n h hudng rd rdt ddn sinh trudng ctia DQ. Cic cdng tinie cd che bdng v i bdn phin ddu cho gii fri Do ldn ban so vdi edng thtic ddi chimg (p^^. Pi, v i pa^.j ^du < 0,05). Trong dd edng tinie che sing A2 cho Do ldn nhdt (3,38 mm). Nhdm edng thtic bdn dam N2 v i N3 cho g i i tri Do tdt nhat (3,10 mm v i 3,15 mm). 6 cic cdng tiiiic tdng hpp, DQ dat gii tri ldn nhdt (3,56 mm) d cdng thtie A2N3 (che 50%*dam 0,3%), rdi ddn g i i fri 3,44 mm d cdng thtic A2N1 (ehe 50%*dam 0,1%) v i tiidp nhat bdng 2,72 mm d cdng tiitic ddi chting (AONO). Tuy nhifin phdn tich theo tifiu chudn Duncan thi khdng c6 su khic bifit rd rfit giira 2 cdng tiiirc A2N1 v i A2N3 vd chi tifiu niy ^ = 0,082).
Ddi vdi chi tifiu H, eic nhan td che sing, phin dam cung cd inh hudng rd rfit vd m i t thong kfi (p„ = 0,000, Pd = 0,000 ddu < 0,05), nhung anh hudng tdng hpp che sing* phin dam lai khdng rd rdt (Pag-a = 0.37
> 0.05). Vdi cic cdng thtic che sing, theo tifiu chudn Duncan H dtrpc ehia li 3 nhdm g i i tq: cao nhat (34,43 em) d cdng thtie A2, 31,45 cm d cdng thirc Al v i nhdm thdp nhdt 27,52 em v i 28,43 cm d cic cdng thiic AO v i A3. Trong khi dd d eie edng tiiiic bdn dam khic nhau, H dupc chia lim 3 nhdm frong dd thap nhat 29,02 cm d cdng thiie NO (ddi ehiing) v i nhdm ed cic g i i tri cao nhdt 30,98 cm v i 31,63 cm ting vdi eie cdng thiic N2 v i N3.
Ddi vdi chi tifiu sd li/ciy, nhin td che sing v i che sing*phan dam l i cd i n h hudng rd rfit ddn chi tifiu niy (p^ = 0,000. p^.j = 0.02, ddu < 0,05). Cdn inh hudng ctia nhdn td phin dam l i khdng rd rdt (pa = 0,67 > 0,05). Trong eic edng thiie che sing, cdng thiic A2 eho sd l i / c i y cao nhdt (14,58 li/ciy), sau dd ddn cdng thtic Al cho 13,10 li/ciy, cudi ciing tiidp nhdt d cic cdng thtic AO (ddi ehiing) v i A3 (che 75%) vdi sd l i / c i y ldn lupt l i 12,50 l i v i 12,35 li.
Trong cic edng thtic tdng hpp ehe sing*phan dam, cie gii h i cua chi tifiu sd l i / c i y dupc chia lim 7 nhdm, nhdm cd gii tn ldn nhat li 15,6 l i / c i y v i 15.07 l i / c i y ling vdi cic cdng thtic A2N3 v i A2N1.
Nhu viy d giai doan 4 thing tudi, cic gii tri trung binh vd Do, H, sd li/cay ting k h i nhanh so vdi giai dogn 2 thing tudi. Khie vdi giai d o ^ 2 thing tudi, d giai doan niy si^ phin hda ciia eic chi tifiu sinh trudng d cic mtic che sing rd ring hem v i cdng tiitic ehe A2 (che 50%) l i cdng tinie tdt nhdt (so vdi
N 6 N G NGHI?P V A PHAT TRI^N N 6 N G T H 6 N - KY l - T H A N G 9/2013
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giai doan 2 thing tudi thi ca 2 edng thtic Al v i A2 ddu la eac cdng thiic frong cimg nhdm tdt nhdt). Vdi nhin td dam, d giai doan 2 thing tudi nhin td n i y khong cd i n h hirdng rd rfit ddn Do, thi d giai doan 4 tiling tudi, nhdm cdng tinie bdn dam N2 (0,3%) v i N3 (0,5%) cho gii tri Do va H tdt nhdt Nhdm cdng thtic tdng hpp A2N1 va A2N3 cho e i c g i i tri cao nhat ve Do v i sd li/ciy.
3.2.3. Glai doan 6 thing tudi
O giai doan 6 thing tudi, cac gia h i trung binh cua Do, H v i sd l i / e i y ldn luat la 4,7 mm, 48,8 cm v i 24 li/ciy, cic gii fri niy ddu xap xi gdp 1.5 ldn so vdi giai doan 4 thing tudi. Ddi vdi chi tifiu Do, tuong tu b giai doan 4 thing tuoi, cic nhan td che sang, phin dam d giai doan niy ddu cd anh hudng rd rfit den ehi tifiu niy 0>as vi Pd ddu < 0,05). Tuy nhifin anh hudng tdng hpp ciia che sing*phin dam lai chtra ro rfit vd mat ihdng kd (P^.j = 0,57 > 0,05). Trong cic cdng tinie che sing, cdng thtic A2 (che 50%) cho gii hi Do cao nhat (5,1 mm), edn cdng thiic A3 (che 75%) l i edng thirc cd g i i fri Do tiiap nhat (4.15 mm). Trong khi dd cdng thiie bdn dam N3 (0,5%) l i cdng thiic tdt nhat frong eie cdng thiic bdn dam vdi gia hi Do dat 4,87 mm, cdn nhdm cdng thiic ddi chiing v i Nl (0,1%) la cic cdng thiic eho g i i tri nay thdp nhdt (4,60 mm vi 4,60 mm).
Ddi vdi ehi tifiu chidu cao eua eay Mun 6 thing tudi, tuang tu nhu vdi chi tifiu Do i n h hudng ciia cic nhin td che sing v i phin dam den ehi tifiu nay l i cd y nghia (Pa^vipj ddu < 0,05) nhung anh hirdng tdng hpp eua chd dd che sing*phin dam la khdng rd rfit (PasM = 0,956 > 0,05). Trong eac cdng thirc ehe sing, edng thtic A2 (che 50%) van l i cdng thtie cho H cao nhdt (54,90 cm) v i nhdm cac cdng thiic cho g i i tri thap nhat van la cic cdng thtic AO (ddi ehiing) va A3
(che 75%). Trong cac cong thtic bdn dam, H cd g i i fri thdp nhdt (46,93 cm) d cdng thiic NO (ddi chimg), sau dd dat 48,73 em d cdng thiic Nl, 49,58 cm a cdng thtie N2 v i cao nhdt (49,83 cm) d cdng thtic N3 (0,5%). Tuy nhifin giCra eac cdng thiic cd bdn dam (Nl, N2 v i N3) su khie bifit l i chua rd rfit vd m i t tiiong kfi (p = 0,254 > 0,05).
Miic dp che sing khae nhau cd i n h hudng rd rdt dfin sd lugng l i binh quan/cay (p^, = 0,00 <
0,05) v i edng tiiirc A2 (che 50%) l i cdng tiiiic tdt nhdt. Tuy nhifin. i n h hudng eiia c i c nhin td phin dgm v i che sing*phan dam ddi vdi chi tifiu niy lai khdng rd ring.
Tdm lai frong giai doan 6 t h i n g tudi, ting trudng ciia c i c g i i tri trung binh vd DQ, H , sd l i / c i y eiing hiang duong vdi giai doan 2 4 t h i n g tudi. O giai doan n i y muc che sing 50% vln Ii phii hpp n h a t Vific che sing b mtic 75% b giai doan n i y khdng nhiing khdng lim ting m i cdn cd i n h hudng kim ham su sinh tnidng ctia cay Mun. Trong c i c cdng thtic bdn dam, cdng thtic N3 (0,5%) l i cdng thtic cho g i i t n cao nhdt vd Do, H v i c i chi tifiu sd l i / c i y . Trong e i c cdng thiic tong hpp che sing*phin dgm, nhdm c i e cdng tiitic A2N1, A2N2 v i A2N3 l i nhdm cho c i c chi tifiu sinh trudng cao. frong do cdng thiic A2N3 (ehe sing 50%* dam nong dp 0,5%) cho g i i tri cao nhdt Tuy nhifin chua ed su khic bifit rd rfit vd mat thdng kfi gitia cic cdng thtic nay. Didu d i n g luu y la cic cdng thtie n i y ddu a mtic che 50%, cho thay nhin td che sing cd anh hudng ldn hon v i rd rfit han so vdi nhin td phin dam frong thi nghifim niy.
4. KET LUAN
Ciy Mun d giai doan vudn irom cd ty lfi sdng khi eao v i sinh trudng k h i nhanh. Sau 6 thing chim sdc ty Id sdng eao nhdt dgt xdp xi 90%; do, H v i sd li/ciy trung binh la 4,7 mm, 48,8 cm v i 24 li/eay. Vific ehe sing v i bdn dam cd i n h hudng rd rfit den cic chi tifiu nay.
Ddl vdi ty lfi sdng, edng thtic che sing Al, A2, A3 cho ty lfi sdng cao hon hdn (gap gan 1,4 ldn) so vdi cdng tiiirc ddi chiing AO (dat 64,3%). Tuy nhifin nhin td phin dam chira cd i n h hudng rd rfit ddn chi tifiu niy.
Ddi vdi cic chi tifiu sinh trudng, nhin td che sing cd anh hudng rd rdt, nhung mtic che sing phil hpp bien ddng tiieo giai dogn tudi. 6 giai dogi 2 thing tudi mic dii c i c cdng thiic ed che sing cho chi tifiu sinh tnrdng ldn han cdng tiitic ddi chiing, nhung ehua cd su k h i c bifit rd rdt giiia c i c edng tiiuc niy.
Tuy nhien ddn giai dogn 4 v i 6 t h i n g tudi thi muc che sing 50% l i tdt uu.
Nhin td dam frong flii nghidm niy m i c dii chua cd anh hudng rd ddn ty \i sdng, nhung lai inh hudng k h i rd ddi vdi c i c chi tifiu sinh tiTidng v i c6 mtic dp anh hudng k h i e nhau d c i c giai dogn tii6i khac nhau. 6 giai doan 2 tiling hidi, c i c cdng tiuic cho g i i tii sinh hirdng cao l i N l (0.1%) v i N2 (0,3%), d giai dogn 4 t h i n g Uidi c i c ndng db bdn cao hon N2 (0,3%) v i N3 (0,5%) ed i n h hudng tdt hon ddn Do v i H. Ddn giai dogn 6 tiling hidi flii edng
106 N 6 N G NGHllP VA PHA r TRIEN NONG T H 6 N - KV 1 - THANG 9/2013
KHOA HpC C6NO NOHfe
tinie N3 (0,5%) dugt: coi l i cdng thiic tdt nhdt Nhu 3. Tlumotiiy P. C. E. et al., 2012. Differential viy cd thd thdy, nhu cdu bdn dam eua ciy Mun tang growth responses in seedlings of ten species of theo tudi frong giai doan vudn uom, frong giai dogn Dipterocarpaceae to experimental shading and 2 ttiing hioi nfin bdn b muc 0,1% ddn 0,3%, cdn frong defoUation. Joumal of Tropical Ecology m:^n-ZU:.
giai doan tir 4 ddn 6 tiling tiidi nfin bdn dam b ndng 4 yifin Hin lim Khoa hoc va Cdng nghfi Vifit dd cao hon (mtic 0,5%). j^a^_ 2007. Danh luc dd Vifit Nam. Nxb Khoa hpe Tii
nhifin vi edng nghfi. H i Ndi.
TJU UEU THAM KHAO 5. Volenec J. J. & S. M. Cunningham, 2005.
l.IUCN, 2013. Red hst of ttireaten species. Effect of applied nifrogen on seedlmg growtii and cotyledon protein utilization of effective and ineffective nodulating alfalfe. Joumal of plant nutrient 18 (7): 1519-1534.
2. Phgm Hoing Hd, 1993. Ciy cd Vifit Nam. NXB Ndng nghidp.
THE EFFECTS OF SHADING AND NITllOGEN FERTILIZER
ON THE SURVIVAL AND GROWTH OF DIOSPYROS MUNS^YXi\mG'S, DURING NURSERY PERIOD Do Anh Tuan Summary
Diospyros mun A-Chev. ex Lecomte is a rare and high economical and conservation value tree species in Vietnam. This research evaluated the effects of shading and nitrogen fertilizer application on the survival and the growth of the seedlings of the species during nursery period. The research appLed the method of split-plot design with 3 replications for two factors: shading with 4 levels (control, 25%. 50%. and 7596) and nitrogen fertilizer application with 4 levels of concentration (control, 0.1%. 0.396, and 0.596). The results showed that the survival and the growth of the seedlings were rather high. After 6 months in nursery, the survival percentage was still up to 9096. the average values of the seeding diameter (Do), height (H), and number of leaves per seedling were 4.7 mm. 48.8 cm and 24 leaves/seedling respectvely. The experiment factors shading and nitrogen fertilizer application had significant effects on these variables. Of which, the optional shading level was at 50%, producing the best survival percentage as well as the best Do, H. and number of leaves per seedling. The most suitable application of N fertilizing was at the concentration of 0.196 - 0.396 in 2 month period and at the concentration of 0.596 in the period from 4 to 6 months.
Key words: Diospyros mun AChev. ex Lecomte, growth, nitrogen fertilizer, shading, sunival.
Ngudi phin b i ^ : TS. Biu Huy Hidn Ngiy nhin bii: 10/7/2013 Ngiy ttidng qua phin bidn: 26/8/2013 Ngiy duydt ding; 4/9/2013
