KHOA HOC
C Q N GNGHE
l\IGHIE!\l CLIU SliXIH TRUOIMG V A SIIXIH KHOI TUOI CUA CAY HdlMG yPaulawrnia fartunel ( s e e m ) H e m s t )
Ll Vdn B6\ Nguyin Vdn KhaS Ll Thj Thanh Hiln''
T6MTAT
Cdy hdng (Paulownia fortune!) Id cdy frdng Idy gd cd nhilu die tinh uu vi^t nhir Sinh tnrdng rdt nhanh. gd nhe. khdng bi ntit khi kh6 vd chtia ham lupng xenluloza cao. Vi vay cdy hdng cd kha nang frd thdnh mpt frong nhung cay cung cdp ngudn nguyfen li$u cho cdc nhd may gidy. Kit qud nghidn cthi cho thay. cdy hong con moc tir hat co cudng dp quang hpp rdt cao 9.2 pmol C02.m"''.s' bdng vdi tdc dd quang hpp ciia cay dau nanh. Hong la cay sinh trudng rdt nhanh. 5 thang sau khi frdng cay cd bd la ldn vdi di$n tich toan bp la dat 12,7±2,1 m^/cay so 0.45±0,19 mVcay ciia cay bach dan ciing tudi. Vdi bp la to va cudng dd quang hpp cao nfin khdi lupng than chinh trung binh la 46,2 kg/cay. chiiu cao 7.4 m, dudng kinh than 17,8 cm, so vdi cdy bach dan tudn tii Id 6,7 kg/cay, 4,5 m va 5,9 cm vao thang thti 15 sau khi frdng. Sinh khdi tuoi cua cdy Hong vi thi cao gdp khoang 6 ldn so vdi cdy bach dan.
Tir khda: Ciy hong, b^ch dan, tSngdien tich la, quang hgp, sinh khoi tuai.
LDATVANDE
Cdy hdng cd tin khoa hpc Id Paulownia spp.
(thudc hp Paulownaceae) Id loai gd nhe vd ciing cd ngudn gdc tir Trung Qudc. Do tdc dp sinh tnrdng cdy hdng frong nhiing ndm dau rat nhanh nin ngudi ta cho rdng cdy nay tiiupc nhdm cay C4 (Woods, 2008).
Vl mdt sinh hpc thi cdy hdng phdt triln nhanh hon cdc loai cay frdng Idy gd khdc. Thdn ciia cdy nay cd thi khai thdc gd sau 7 - 8 ndm frdng niu nhu qudn ly tdt. Theo cdc cupc khdo sat cho thay, ddi vdi gidng P.
fortunei dudng kinh cdy ngang ngirc tdng tnrdng hang ndm cd thi dat trung binh 34 cm, cd nhiing trudng hpp dat 7-8 cm. Tdng trudng v l thi tich gd cdy cd till dat 0,03-0,05 m^ gd/ndm, tdi da cd till lln din 0,2 m^ gd/ndm/cdy. Gd ciia cdy hdng cd nhirng ddc tinh uu vilt nhu nhe (dung frpng bdng 250-300 kg/m^ so vdi bach dan (Eucalyptus camaldulensis Dehnh) Id 544 kg/m^, khdng cong vinh, khdng nut, h i sd CO nit thap, d l phoi khd, d l chi hiln, gd khdng miii. Ddy la nhirng ddc tinh quy ctia gd md khdng phdi cay ndo ciing cd dupe. Thdnh phan gd ciia cdy hdng chtia xenluloza khoang 4649%, hembcenluloza 22-25%, linhin 21-23% (El-Showk va El-Showk, 2003;
LivdOda,2007).
Do v^y, cdy hdng vdi ddc tinh uu vilt la sinh khdi ldn, spi xenluloza chat lupng tdt vd cd ham lupng cao cd thi la ngudn nguyin Hlu lam giay. Vi vdy vile frdng lodi cay nay cd thi tao nin ngudn thu nhdp
' Khoa Nong nghidp vd Sinh hpc LTng dyng, tnrdng D^ii hpc Can Thd
^ Chi eye Bao v$ Thyc v§t tinh VTnh Long
dang k l cho ngudi dan sdng frong vimg ndy. Vile nghiln ctiu kha ndng tao sinh khdi tuoi ciia cdy hdng Id diiu h i t sire can thilt d l lam co sd cho vile phat triln loai cay ndy, thay till hodc bd sung vdo ngudn gidng cdy lam nghilp hi|n nay d DBSCL.
L VAT I 4 U , NOI DUNG VA PHUONG PHAP NGHIEN CUU 1. Mtic tilu vd ndi dung nghiln cuu
Mtic tilu: danh gid khd ndng thich nghi, sinh trudng vd phdt trien ciia cay hdng cd liln quan den tilm ndng tao sinh khdi.
Ndi dung nghiln ctiu: (1): So sdnh cudng dp quang hpp cua cdy hdng vdi mdt sd cdy frdng khac.
(2): Khao sat kha ndng sinh trudng, tao sinh khdi tuoi ctia cdy hdng frong diiu kiln frdng d DBSCL
2. Vdt li|u nghiln cihi
Cdy hdng (Paulownia fortunei (seem) Hesrat), cdy hdp (Zeamays), cdy ddu ndnh (GlycinemaxL.) a giai doan cay con dupc sii dung d l thtic hiln tiii nghilm. May do cudng dp quang hpp U 6400 dupc su dung d l do quang hpp ciia Id.
Cay hdng (P. fortunei) vd cay bach dan (E.
camaldulensis Dehnh>> gieo hi hat dupc frdng dl so sdnh sinh trudng va sinh khdi.
3. Phuong phdp thi nghi|m
a. Thinghiim 1. So sinh cuong do quang hop eda ciy hdng voi cay bdp vi diu ninh
Thdi gian tien hanh tir tiidng 11/2009 din 4/2010. Dia diem tai nhd ludi Bd mdn Sinh ly-Sinh hda, Khoa Ndng nghilp va Sinh hpc Ung dung, Trudng Dai hpc Cdn Tho. Vdt U|u d l do cudng dp 80
NONG NGHIEP VA PHAT TRIEN NONG
T H 6 N- KY 1 THANG 9/2011
KHOA HQC
C Q N G N G H | quang hpp Id cdy hdng con cd chiiu cao tii 20 - 25cm, 8-10 Id tiiat; cdy bdp con 20 ngdy tudi (6-8 Id) thudc nhdm cdy C4; ddu ndnh 30 ngdy tudi thudc nhdm cdy C3. Sii dting may do quang hpp hieu LI6400 d l do cudng dp quang hpp.
Cdc thdng sd do Id tdc dp quang hpp (pmol C02.m-^.s-^), dp sudt tiiilu hoi nudc ciia Id (Vpdl = Vapor pressure deficit on leaf, don vi do kPa). Mdi cdy do 5 Id, mdi loai do 10 cdy (10 ldn ldp lai). Nhu vdy mdi loai cdy cd 50 ldn do.
Quan sat sir hiln diln cua hat luc lap frong t l bdo bao bd mach vd t l bdo thit Id ciia Id cdy hdng.
Muc tilu quan sat la xem cd str hiln diln ciia hat luc lap frong t l bdo bao bd mach hay khdng?
b. Thinghiim 2. Khao sit kha ning sinh trudng vi phit triin ciy hdng
Cdy hdng gidng (P. fortune!), gieo tir hat cd 8-10 Id that dem frdng. Dia diim frdng tai Khu II, Dai hpc Cdn Tho. Thdi gian bdt dau frdng 28/12/2009. Diln tich frdng cdy hdng la 1.200 m^, cu ly frdng: hdng each hdng 4 m vd cdy cdch cdy 4 m. Tdng sd cdy dem frdng Id 75 cdy. Kich tiiudc hd 40 x 40 x 40 cm.
Trudc khi frdng bdn Idt 1 kg phdn chudng dd hoai muc cdng vdi 5 g Tricho DHCT/gdc. Sau khi frdng tudi nude 2 Idn/ngdy vdo 4 tudn ddu (vi frong thdi gian nay hodn todn khdng mua). Bdn phdn cho cdy frong 4 thang ddu tien sau khi frdng vdi lupng 40-50 g DAP + 15 g urI + 20 g kali clorua/gdc. Tir thdng tiiii 5 frd di, cii mdi 2 tiidng bdn 100 g DAP + 30 g urI + 40 g kali clorua/gdc. Do la cay to, mim nin cdn tiling nhdm chich hiit rdt ua tiiich. Vi vdy, thudng xuyIn kilm fra chdi ngpn niu thdy xudt hiln cdn tiling phd hai tiii tiln hdnh phun xit Ddi vdi cdy bach dan, tiln hdnh nghiln ciiu 15 cay con cd chiiu cao trung binh 20 cm, frdng tiianh hang vdi khoang cdch 2 met/cdy. Ky tiiudt frdng vd bdn phdn, tirdi nudc gidng nhu frdng cdy hdng.
Cic chi tiiu theo ddi: Hdng tiiang ghi chip cdc thdng sd vl chiiu cao cdy, sd Id, dudng kinh gdc each mdt ddt 10 cm, chiiu dai Id (tinh tii cudng din chdp Id), chiiu rdng Id (tinh noi rdng nhdt), diln tich la dupe tinh bdng cdch lay dai Id nhdn rdng Id vd nhdn h$ sd 0,9 (cdy hdng, cd la \o frdn) vd nhdn h i sd 0,75 dp dvmg cho cdy bach dan (cd la nhd ddi) mdi cdy do 3 Id ldn nhdt Din tiidng tiiii 15 sau khi frdng, ddn cdy hdng vd cdy bach ddn, cdn khdi lupng tuoi
ciia than chinh, cdnh. Id d l so sdnh khdi lupng tuoi.
Sd hlu dupc xti ly bdng phdn mim SPSS V.16.0.
•.KET QUA VA THAO LUAN
1. So sdnh cudng dd quang hpp ctia cdy hdng vdi cdy bap vd cdy ddu ndnh
So sdnh cudng dp quang hpp vd dp sudt thilu hoi nudc frdn la (Vpdl) ciia cdy hdng vdi hai loai cdy hoa mdu khdc Id cdy bdp (cdy C4), cdy ddu ndnh (cdy C3) dupc trinh bdy dbang 1.
Bdng 1. So sdnh dp sudt thilu hoi nudc frIn Id (Vpdl) vd cudng dd quang hpp ciia cdy hdng, cdy bdp vd cdy
ddu ndnh Loai cdy
Hdng Bdp Ddu ndnh LSD 0,05 F (P<0,05) CV(%)
Vpdl ">
(kPa) 3,19 a 1,86 b 2,67 ab 0,93
* 30,5
Lupng CO2 hdp thu (pmol.m"^.s"^)
9,2 b 28,1a 13,5 b 12,3
* 15,07
'^-' Ap suit thiiu hoi nudc tiin la. Cic gii tii trung binh theo sau bdi cic chu cii giing nhau thi khic biit khdng y nghia vdi nhau qua kiim dinh LSD. *: khic biit a miic ynghia 5%.
Thdng sd dp sudt thilu hoi nudc (Vpdl-Vapor pressure deficit on leaf) Id thdng sd chi mdi liln h i dm dp khdng khi vd la, niu nhu thdng sd ndy cdng ldn thi am dp khdng khi cdng thap, la thodt nudc manh. Ngupc lai, thdng sd nay nhd thi dm dp khdng khi ldn (Prenger vd Ling, 2000). Thdng sd dp sudt thilu hoi nudc frIn Id cdng cao thi cdy thieu nudc cang nhilu, thdng thudng gid tri ciia thdng sd ndy ndm trong khoang 1-3 kPa (Teskey et al., 1994).
Trong ciing cudng dp biic xa hiru hiiu quang hpp (PA^ thi cay hdng cd dp sudt tiiilu hoi nude ciia la cao nhdt (3,19 kPa) so vdi hai loai cdy cdn lai. Ngupe 1^, cdy bdp cd Vpdl tiidp nhdt (1,86 kPa) vi cdy bdp thudc nhdm cdy C4, sir dung nude hi|u qua hon cdy C3 (Lee vd Leegood, 1993).
Theo thdng sd lupng hdp thu CO2 (cudng dp quang hpp) thi cdy hdng hdp thu thdp hon cdy bdp, tudn ttr la 9,2 vd 28,1 pmol.mls"^. Tuy nhiln, do cay hdng cd bd la to, nin lupng CO2 cd dinh dtrpc la rat ldn d l tao ra sinh khdi vupt bdc so vdi cdy khdc (thi nghilm 2). Tir hai tiidng sd (Vpdl vd lupng hap thu CO2) d bang 1, cho phep ddt ra cau hdi lilu cdy hdng cd phdi cdy C4 nhu y kiln ciia Woods (2008). Khi cdt
KHOA HOC CONG N G i i i
ngang la cay hdng va quan sat giai phdu la cho thay, te bdo bao quanh bd mach khdng cd chtia hat luc lap.
Trong khi dd, t l bdo thit la thi cd chua nhilu hat luc lap (hinh 1).
Cudng dp quang hpp ciia cay hdng thdp so vdi cay bdp, chi bdng cudng dp quang hpp ciia cdy dau
ndnh, nhung thdng sd Vpdl ciia cdy hdng lai cao hon cd y nghia thdng k l so vdi cdy bdp. Hon niia, t l bdo bao bd mach d Id ciia cdy hdng khdng c6 chiia hat luc lap, cho phep nghi ngd cdy hong khdng phai la cdy C4.
Hmh 1. (a) T l bdo bao bd mach khdng cd hat luc lap; (b) t l bdo thit Id cd chiia hat luc lap, dd phdng dai 400 ldn
2. Khdo sdt khd ndng sinh trudng vd phdt triln cdy hdng
a. Diin tich la/ciy vi soli
Kit qua khao sat kha ndng phat triln la ctia cdy hong theo timg thang dupc trinh bay d bang 2.
Bang 2. Sd Id/cdy vd tdng di|n tich Id ciia cdy hdng vd cdy bach ddn theo thdi gian frdng Thdi gian quan sat So la/cay Tong di?n
tich la/cay Thang thu 1 sau khi trong
Cay hong Cay bach dan T-test (P<0,05)
8,2±1,3 16,2±3,3
*
0,22±0,09 0,0114±0,014
* Thang thu 2 sau khi trong
Cay hong Cay bach dan T-test (P<0,05)
17,3±1,8 24,8±3,3
*
2,22±0,79 0,058±0.017
* Thang thii 3 sau khi trong
Cay hong Cay bach dan T-test (P<0,05)
28,9±2,3 40,6±6,1
*
7,24±2.61 0,25±0,04
* Thang thii 4 sau khi trong
Cay hong Cay bach dan T-test (P<0,05)
42,4±2,9 60,2±6,0
*
9,02±2,5 0,35±0,13
* Thang thur 5 sau khi trong
Cay hong Cay bach dan T-test (P<0,05)
58,1±4,4 75,9±7,4
*
12,7±2,1 0,45±0,19
*
*• khic biit cd y nghia tiiong ki qua kiim dinh T-test muc y nghia 5%
Cay hdng cd bd la to, it khi ning la tir khi frdng din thdng thti ndm. Sau thdi gian nay cdy hdng bdt ddu rung la vd nhirng la mdi hinh thdnh cd kich
thudc nhd hon cac la ban ddu. C! thdng thii nhdt sau khi frdng thi tdng diln tich la ciia cay hdng dupc u6c lupng la 0,22 m^ Id/cay, so vdi cdy bach ddn Id 0,0114 m^ la/cay. Sir khdc biet nay cd y nghia thdng kl, mSc dii sd la/cay thi cay hdng d thdi diim ndy Id 8,2±1,3 Id, it hon cay bach dan (16,2± 3,3 Id). Tuong ttr nhir vay, vdo nhirng thdng k l tiip thi tdng diln tich la tdng rdt nhanh tiian bi Id 2,22, 7,24, 9,02, 12,7 m^
Id/cdy tuong ting vdi thang thti 2, 3, 4 vd thir 5 sau khi frdng. Tdc dd phat friln Id ciia cdy hdng gdp 20 ldn so vdi cay cdy bach dan vd ban la rdt rdng so vdi Id cdy bach dan.
Hon niia, tdc dp cd dinh CO2 ciia chiing bdng voi tdc dp cd djnh CO2 cua cay ddu ndnh (bang 1). Diiu nay giai thich tai sao cay hdng cd tdc dp sinh trudng cao ma khdng phai cdy frdng lay gd ndo cd dupc.
b. Dudng kinh thin
Dudng kinh thdn cung la mpt thdng sd quan frpng de danh gia tdc dp sinh trudng cua cdy. Cay hdng con gieo tir hat frong bdu 3 thdng tudi cd tiling binh 8 Id cd dudng kinh thdn trung bmh 0,8 cm mdt thdng sau khi frdng. So vdi cdy bach dan cd tiling binh 16 la (bang 2), dudng kinh tiidn tiung binh \k 0,2 cm. Sti khdc bi|t nay cd y nghIa thdng kl bdng kilm dinh T-test (P<0,05). Ddc biit la dudng kinh thdn cay hdng phdt triln rat nhanh frong nhirng thdng sau dd. Din thdng thii 13 sau khi frdng, cdy hdng cd dudng kinh thdn trung binh la 14,5 cm.
Trong khi dd, dudng kinh thdn cdy bach dan trung binh la 4,1 cm (hinh 3). Theo Woods (2008), gidng P.
elongata, cd dudng kinh tiidn trung binh 8,5 cm (2 nSm tudi) vd 16 cm (3 ndm tudi). Nhu vdy, gidng P. fortunei
82 NONG NGHIEP VA PHAT TRIEN NONG THON KY 1 - THANG 9/2011
KHOA HOC
C Q N GNGHE
frong tiii nghilm nay dirdng nhu thich hpp vdi vimg ndng vd dm nhu d ddng bdng sdng Ciiu Long.
Hinh 3. Bilu dd md td tdng trudng ciia dudng kinh thdn cdy hdng vd cdy bach ddn
theo thdi gian frdng
ThAng aau khi li^nii
Hmh 4. Bilu hdng vd
c. Chiiu cao ciy
Chieu cao cdy la mpt thdng sd quan frpng de ddnh gid sinh tnrdng vd phdt triln ctia cdy. Cdy hdng phat friln chiiu cao rat nhanh frong 5 thdng sau khi frdng; rilng nhirng thdng sau dd cdy cd chiiu hudng phdt friln chdm lai (hinh 4). So vdi cdy bach dan thi chiiu cao cay hdng vupt frpi hon hdn, str khdc biit ndy cd y nghia thdng k l bdng kilm djnh T-test (P<0,05). Vi dii vao thang thii 7 sau khi frdng cdy hdng dat chiiu cao 5,5 met cdn cdy bach ddn chi dat chiiu cao la 2,4 met Trong nghiln ctiu khdc, cay hdng gidng P. elongata, cd chiiu cao cdy sau 1 ndm frdng Id 5 met (Woods, 2008) vd 3,8 met (Huaxin, 2007).
d. So sinh khoi lugng tuai ciy hdng vi ciy bach dan vao thing thu 15 sau khi tiong
De so sanh sinh trudng vd phdt triln cay hdng vd cdy bach dan, frong nghiln ctiu nay dd tien hdnh thu hoach 15 cay mdi loai. Cac thdng sd ddnh gid vl sinh tnrdng vd phdt triln ciia hai loai cdy nay dupc frinh bdy d bdng 3.
dd md td tdng trudng v l chiiu cao cdy cdy b^ch ddn theo thdi gian frdng
Bdng 3. So sdnh sinh khdi tuoi giiia cdy hdng vd cdy b^ch ddn vdo giai d o ^ 15 thdng sau khi frdng
Loai cdy Cdy hdng Cay bach dan T-test (P<0,05)
Khdi lupng than chinh (kg)
46,2 ±23 6,7 ±5,9
*
Chiiu cao cdy (m) 7.4 ±1,4 4,5 ±1.3
•
Dudng kinh thdn (cm) 17,8 ±3,8
5,9 ±2,2
k
Khdi lupng cdnh vd la (kg)
20 ±8,2 4,2 ±3,2
*
Khdi lupng todn cdy (kg)
66 ±10,4 10,9 ±3,1
* khic biit cdy nghia thong ki qua kiim dinh T-test mdc y nghia 5%
Do bd Id cua cay hdng phdt triln manh vd cudng dp quang hpp khd cao (bdng vdi cdy ddu ndnh) nin sinh khdi tuoi cua nd rdt ldn sau mpt thdi gian ngdn.
Theo kit qua khao sdt nay khdi lupng than chinh tiling binh la 46,2 kg/cdy, so vdi cay bach dan chi dat dupc 6,7 kg/cdy. Qua kit qua nay cho thdy, frong cimg thdi gian sinh trudng cdy hdng tdng tnrdng manh hon vd cho sinh khdi cao hon cdy bach ddn khoang 6 ldn.
Mdu ciia thit gd cdy hdng frdng hon rat nhilu so vdi thit gd cua cdy bach dan. Theo nghiln ciiu ciia Woods (2008), ham lupng spi xenluloza ciia cdy hdng cao 4649% vd spi ciia nd dai, mdu frdng rat thudn lpi frong chi biin thdnh bdt gidy (hinh 5a).
Tuong ttr nhu dd trinh bdy phdn frIn, chiiu cao cdy vd dudng kinh thdn vdo giai doan ndy ctia cdy hdng vupt hon hdn cdy bach ddn (hinh 5b).
.5a , f>h
Hinh 5. (5a) Spi gd cdy hdng ddi mdu trdng; (5b) Thdn chinh ciia hdng vd cdy bach ddn Itic 15 thdng sau khi frdng
KHOA HOC
C Q N GNGHE
Cung theo kit qua d bang 3, khdi lupng canh Id cdy hdng ciing cao hon cdy bach dan. Ngodi ra, frong la cdy hdng (P. fortunei) cdn chiia mdt lupng protein khd cao, bdng 1,632% tdng lupng chat khd (Barton et al., 2007) vd Id ngudn thiic dn cho gia siic khi cdy dupe khai thdc.
IV. KET LUAN
Cay hdng (P. fortunei) cd tdc dp quang hpp bdng vdi tdc dp quang hpp cay ddu ndnh.
Tdc dp phdt friln bp la ciia cdy hdng cao gdp 20 lan so vdi bp la cua cay bach dan frong cimg thdi gian sinh tiirdng.
Chiiu cao cdy va dudng kinh than ciia cay hdng cao hon cd y nghia so vdi cay bach ddn.
Sau 15 thang frdng cdy hdng sinh trudng vd phdt triln rat nhanh, tao sinh khdi tuoi rat ldn so vdi cay bach dan vi vay loai cdy nay cd tiem ndng frdng d l lam bdt gidy tai DBSCL.
TAI L P THAM KHAO
1. Barton, I. L, I. D Nicholas and C. E. Ecroyd., 2007. Paulownia. Forest Research Bulletin Number 231. ISSN 1174-5096. New Zealand Forest Research Institute Ltd.
2. El-Showk, S. and N. El-Showk., 2003. The
Paulownia tiee - An alternative for sustainabk forestry. The Farm. http://www.cropdevelopment org/paulownia/ Brochure.pdf. (Accessed 15th, December 2007).
3. Huaxin Z., 2007. Paulownia as an energetic crop - producer of a aoUd bio-fuel The Chinese Academy of Forestry.
4. Lee, P. J. and R. C. Leegood., 1993. Plant biochemistry and molecular biology. Chichester.
JohnWilley,p.269.
5. Ii, P. and J. Oda., 2007. Flame retardancy of paulownia wood and its mechanism. / Mater. Sci 42:
8544-8550.
6. Prenger, J. J. and P. P. Ling., 2000.
Greenhouse Condensation Confrol. Fact Sheet (Series) AEX-800. Ohio State University Extension, Columbus, OH.
7. Teskey, R. O., H. L. Gholz and W. P. J.
Cropper., 1994. Influence of climate and fertilization on net photosynthesis of mature slash pine. Tree Physiology. 14:1215-1227.
8. Woods, V. B., 2008. Paulownia as a novel biomass crop for Northern Ireland? Occaasional publication No. 7. AFBI Hillsborough, Large Park, Hillsborough, Co. Down, Northern Ireland BT26 6DR.
STUDYING OF THE GROWTH RATE AND FRESH BIOMASS POTENTIAL OF PAULOWNIA TREE (Paulownia fortunei (seem) Hemst)
Le Van Be, Nguyen Van Kha, Le Thi Thanh Hien Summary
Paulownia iortunei, which is a wooden tree species with properties of fast growing as well as light wood, is not cracked in dried situation and high quantity of cellulose. Moreover, Paulownia has been considered as tree of supplying wood for the paper mills in the Mekong delta. The results showed that the seedling of Paulownia had a high assimilation rate of COj of 9.2 pmoLm'^.s*. This value is equal to the photosynthetic rate of soybean. Total leaf area of this species at age of 5 months after planting reaches up tp 12.7±2.1 mVplant, compared to the figure of Eucalyptus of 0.45±0.19 m^/plant After planting 15 months, on average, the fresh biomass, height, and diameter of a paulownia free has values of 46.2 kg of main stem weight. 7.4 meter in height, and 17.8 cm of diameter respectively, compared to the figure of a Eucalyptus tree of 6.7 kg of fresh biomass, 4.5 meter height, and 5.9 cm diameter.
Keywords: Paulownia, photosynthesis, total leaf area, 6-esh biomass.
Ngudi phdn bi|n: TS. Dd Anh Tudn
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