American Journal of Plant Sciences, 2011, 2, 644-649
doi:10.4236/ajps.2011.25076 Published Online November 2011 (http://www.SciRP.org/journal/ajps)
Variation in Wood Properties and Growth in Some
Clones of Populus deltoides Bartr. ex Marsh
P. K. Pande
Wood Anatomy Discipline, Botany Division, Forest Research Institute, Dehradun, India.
Received October 27th, 2010; revised November 27th, 2010; accepted January 11th, 2011.
ABSTRACT
The present paper deals with within ramet radial, intra- and inter-clonal variations in the wood element’s dimensions
and specific gravity o f 10 clones of Populus deltoides Bartr. ex Marsh. The growth parameters namely ramet height and
DBH were also considered for the study. Study material was collected from the 10 clones of Populus deltoids raised by
WIMCO Plantations Ltd. at Rudrapur (Udhamsingh Nagar), India. Three clones were parent viz. G48, S7C8 (female)
and G3 (male). Other clones represent hybrids of F1 generation. Inter- and intra-clon al variations were significant for
all the wood traits except vessel element length for intra-clonal variations. Within ramet variations due to radial loca-
tion were significant for fiber length and specific gravity with increasing trend from pith to periphery. Interaction of
clone*replication was also significant for all the wood traits. Variations were significant for the DBH for the clones.
Fiber length and sp ecific gravity was significantly higher in fema le while wall thickness and vessel element length was
in male clones (P < 0.01). Female parents (G48 and S7C8) showed higher fiber length and specific gravity than of the
male parent (G3) while vessel element diameter and wall thickness was higher in male parent (G3). Fiber length was
higher in offspring than the parent clones which may be the reflection of hybrid vigor for the trait. The clones of F1
offspring followed the similar patterns for the other wood traits as in the parent clones. Hierarchical cluster analysis
showed that W/A 39 (male) and W 39 (female) clones of F1 generation were highly divergent than of the other clones.
Keywords: Fiber Length, Specific Gravity, Vessel Elemen t Length Wall Thickness, Wood Variations
1. Introduction
Wood quality and growth are two important parameters
need to be analyzed for the utilization and development
of new clones. Populus deltoides Bartr. ex Marsh is
grown under different forestry programs as clonal planta-
tions to ensure the genetic superiority for better growth
and superior wood quality.
The variability in wood anatomical characteristics has
profound influence on the properties of wood [1,2]. Fea-
tures of interest in this connection include cell size, pro-
portion and arrangements of different elements of se-
condary xylem and specific gravity. The general pattern
of variation in wood element dimensions is found not
only within a species but also observed within a tree by
many a worker [3-5].
Variations in the dimensions of wood elements and
specific gravity both within tree and among the clones
have co me un der clo se scr utiny in r ecen t year s. Th er e are
reports available on the variation in wood anatomical and
other properties in different clones of Populus elsewhere
[6-9].
Populus deltoides showed intra- and inter-clonal vari-
ability in wood traits [8-11]. So, the close scrutiny of
different clones is essential to understand the variability
trends for different wood traits in the species. The wood
elements dimensions and specific gravity are the impor-
tant parameters to be assesses in terms of their within
ramet, intra- and inter-clonal variability so that clones
having desired wood traits can be used for the develop-
ment of new clones. Hence, the present paper deals with
the, inter- and intra-clonal and within ramet radial varia-
tions in wood anatomical parameters and specific gravity
of 10 clones of Populus deltoides.
2. Materials and Methods
2.1. The Experimental Site
Study site was located at Rudrapur (Udhamsing Nagar),
Uttarakhand, Ind ia. It is situated at around 28˚N latitude;
78˚E longitude and at the altitude of 200 m asl (Figure 1).
The annual rainfall was 1200 mm; of which 88% occurs

Variations in Wood Properties and Growth in Some Clones of Populus deltoides Bartr. ex Marsh645
during June-August. The average maximum summer
temperature (April-June) was 36.7˚C and average mini-
mum temperature (December-February) was 7.5˚C (2005-
2006). The soil of th e site was sandy loam.
2.2. Planting Material
The growth parameters namely ramet height and DBH
were measured for each individual before the collection
of wood samples. Study material was collected from the
10 clones of Populus deltoids raised by WIMCO Planta-
tions Ltd. at Rudrapur (Udhamsingh Nagar), India. Three
clones were parent viz. G48, S7C8 (female) and G3
(male). Other clones represent hybrids of F1 generation.
The year of plantation was February, 2000 and the month
of collection of samples was October, 2007. The soil of
the plantation site was sandy loam. The clones were
raised in Randomized Block Design. The spacing of
clonal trial was 5 × 5 m. The details of clones are given
in Table 1.
2.3. Sampling
Wooden cores were extracted from three replicate ramets
Figure 1. Location map of the site.
Table 1. Wood (µm) and growth traits of Populus deltoides clones.
Clone Parents Generation Sex FL SD FDSDWT SD VL SD VD SD SG
DBH
(cm) Height (m)
Kranti G48*G3 F1 F 1048.7 145.727.84.34.8 0.92560.2101.2104.4 19.8 0.333 24.016.5
S7C8 P P F 1140.0 161.025.74.34.50.92560.2125.7103.1 26.3 0.368 23.416.1
G48 P P F 1161.8 169.825.74.44.51.07552.5113.896.1 20.7 0.423 23.416.6
W. 39 G48*G3 F1 F 1229.3 131.325.32.43.90.42572.388.5106.7 18.6 0.420 31.821.5
Bahar G48*G3 F1 F 1190.0 161.124.8 3.4 3.90.70531.9107.896.3 18.6 0.419 26.2 18.3
Udai G48*G3 F1 M 1202.1 182.125.93.94.50.99539.3107.895.3 18.5 0.383 25.117.9
W. 22 G48*G3 F1 M 1136.3 133.726.23.24.30.89558.099.5109.5 19.1 0.367 28.519.6
G3 P P M 1048.2 201.128.15.45.01.36559.4142.3108.4 31.2 0.366 17.615.3
Cp82-5-1 S7C8*G3 F1 M 1049.0 160.223.34.34.21.11558.2115.6105.1 29.5 0.349 17.415.9
W-A/39 G48*G3 F1 M 1057.0 191.623.74.63.91.10597.8133.6 104.3 23.0 0.379 21.323.9
Note: FL = fiber length, FD = fiber diameter, WT = wall thickness, VL = vessel element length, VD = vessel element diameter, SG = specific gravity, SD =
standard deviation, DBH = Diameter at breast height.

Variations in Wood Properties and Growth in Some Clones of Populus deltoides Bartr. ex Marsh 646
of each of the 10 clones at 3.17 m height from the base
from the north direction. Each core was divided into three
pith to periphery locations viz. inner, middle and outer. In
total 90 samples were considered for anatomical studies
viz. fiber length, fiber diameter, wall thickness, vessel
element length, vessel element diameter and specific
gravity. Standard laboratory methods were followed for
the preparation of macerations. Wooden cores were frag-
mented into small pieces and put into the test tube. The
material was macerated with 50% HNO3 and a pinch of
KClO3. The macerated wood elements were thoroughly
mixed and were spread on a glass slide and observations
were taken under compound microscope [12]. Measure-
ments for fiber length, fiber diameter, wall thickness,
vessel element length and vessel element diameter were
taken from the macerated wood. Twenty five unbroken
cells were sampled for the measurement of each parame-
ter [13]. Basic density of core samples was determined as
the ratio of oven dry weight vs. green volume. The green
volume was determined by water displacement method.
Specific gravity is the ratio of the density of the core
sample vs. density of water [12].
2.4. Statistical Analysis
The data so obtained were statistically analyzed using
SPSS 10. Multivariate analysis was done to test the with-
in ramet radial and intra- and inter-clonal variations. Hi-
erarchical cluster analysis was done with SPSS 10 for
wood anatomical properties and sp ecific grav ity and grow th
parameters together using “Squared Euclidean Distance”
method. The hierarchical grouping develops a relation-
ship between clones that are maximally similar for speci-
fied traits. Each of the clones is genetically different
from another. However, the extent of difference might be
varying to a certain degree. Thus, during clustering num-
ber of clones may vary from one to the total number of
clones used. To optimize the number of cluster, a cut of
line was derived on the dendrogram that was close to
1/5th of the value. Five numbers of clusters were deve-
loped based on the information.
3. Result and Discussion
Tables 1-5 show results obtained on the various aspects
of study.
The range for fiber length for different clone was
1048.2 (G3 ) - 1229 .3 µm (W -39); 23 .3 (Cp8 2-5-1) - 28.3
µm (G3) for fiber diameter; 3.9 (W-39) - 5.0 (G3) µm for
wall thickness; 531.9 (Bahar) - 597.8 (W/A 39) µm for
vessel element length; 96.1 (G48) - 109.5 (W 22) 109.5
for vessel element diameter and for 0.333 (Kranti) -
0.423 (G48) specific gravity. The average ramet height
(m) of the clone ranged from 15.3 (Cp82-5-1) - 23.9
(W/A 39) m while DBH (cm) ranged from 17.4 (Cp82-
5-1) - 28.5 cm (W 22 ) (Table 1).
Table 2 shows multivariate analysis of wood ana-
tomical variations of different clones of Populus del-
toides. Inter- and intra-clonal variations were significant
for all the wood traits except vessel element length for
intra-clonal variations. Within-ramet variations due to
radial location were significant for fiber length and spe-
cific gravity. Interaction of clone*replication was also
significant for all the wood traits. Variations were sig-
nificant for the DBH for the clones. Significant diffe-
rences in average specific gravity of different clones of
different species of Populus were reported [6,8]; in Tec-
tona grand is [14] and in Eucalyptus tereticornis Sm. [15,
16]. In contrary, non-significant radial and directional
variations in specific gravity and fiber length in different
clones of Dalbergia sissoo were reported by Pande and
Singh [17], however these variations were significant due
to height of the ramet. Significant inter-tree variation in
specific gravity of Dalbergia sissoo was reported by
Pande [18] and in Lucanea leucocephala by Pande et al.
[19]. Similarly, significant differences among the differ-
ent clones of different species in average fiber length
were reported by many a worker [6,8,9,15,17,20]. Inter-
clonal variation in vessel element dimensions in Dalber-
gia sissoo was reported by Pande and Singh [17]; in
Populus deltoides by Chauhan et al. [8] and in Tectona
grandis by Rao and Shashikala [21]. Significant intra-
clonal variations were reported by Gautam [10] in L-34
clone of Populus deltoids while within-ramet radial
variation was significant for specific gravity with the
increasing trend from pith to periphery and related to the
cambial age of the wood. The increasing trend from pith
to periphery for average fiber length and specific gravity
was also noticed in the present study. Within-ramet
non-significant radial variations for most of the wood
traits showed no impact of age on the dimensions of
wood elements and regulate mostly homogeneous wood
properties within the ramet. Intra-clonal significant vari-
ations indicated that differential wood properties might
be expected from the population of the same clone.
Fiber length and specific gravity was significantly
higher in female while wall thickness and vessel element
length was in male clones (P < 0.01). Female parents
(G48 and S7C8) showed higher fiber length and specific
gravity than of th e male parent (G3) while vessel diame-
ter and wall thickness was higher in male parent (G3).
Fiber length was higher in offspring than the parent
clones which might be the reflection of hybrid vigor for
this trait. The clones of F1 offspring and parents fol-
lowed the similar pattern for the other wood traits (Table
3).
Hierarchical cluster analysis was done using “Squared
Euclidean Distance” for all the 10 clones considering all

Variations in Wood Properties and Growth in Some Clones of Populus deltoides Bartr. ex Marsh647
Table 2. ANOVA for wood traits of different clones of Populus deltoids.
Mean Sum of Square (MSS)
Source of variation df FL FD WT VL VD SG
Clone 9 44747.4** 43.6** 1.87** 4046.8** 311.2** 9.198E–03**
Replication 2 72296.5* 22.9** 0.661** 2442.8 517.4* 5.814E–03**
Location 2 21675.3** 3.03 0.103 2337.8 203.3* 3.568E–03*
Clone*Replication 18 26082.0** 13.45** 0.76** 2575.5** 239.04** 4.926E–03**
Error 58 4265.5 3.08 0.116 1032.6 65.0 1.263E–03
Table 3. Mean wood traits as per the sex.
Std. Error
Dependent Variable Sex Mean (µm) 95% Confidence IntervalLower Bound Upper Bound
FL Female 1148.9 16.6 1115.76 1182.1
Male 1103.4 16.6 1070.23 1136.6
FD Female 25.4 0.41 24.60 26.2
Male 25.8 0.41 25.02 26.7
WT Female 4.2 0.09 4.03 4.4
Male 4.5 0.09 4.32 4.7
VL Female 548.1 5.56 537.02 5
Male 562.378 5.562 551.289 573.466
VD Female 100.511 1.573 97.376 103.647
Male 101.222 1.573 98.087 104.358
SG* Female 0.392 0.007 0.378 0.406
Male 0.367 0.007 0.353 0.381
Note: * = No unit. Table 4. Constitution of different clusters.
Cluster Number No. of clones in the cluster Clone number and sex
1 3 G3 (Male), Cp82-5-1 (Male), Kranti (Female)
2 1 W-A/39 (Male)
3 3 S7C8 (Female), W 22 (Female), G 48 (Female)
4 2 Bahar (Female), Udai (male)
5 1 W 39 (male)
Table 5. Mean value of wood element’s dimensions (µm) and specific gravity.
Parameters/Cluster Number FL FD WT VL VD SG DBH (cm) Height (m)
1 1048.6 26.37 4.67 559.27 105.97 0.349 19.67 15.9
2 1057.0 23.7 3.9 597.8 104.3 0.379 21.3 23.9
3 1146.03 25.87 4.43 556.8 102.9 0.386 25.1 17.43
4 1196.05 25.35 4.2 536.6 95.8 0.401 26.8 18.1
5 1229.0 25.3 3.9 572.3 106.7 0.420 31.8 21.5

Variations in Wood Properties and Growth in Some Clones of Populus deltoides Bartr. ex Marsh 648
Figure 2. Dendrogram using acerage linkage (between the groups) for the different clones cl of Populus deltoids.
the wood and growth traits. Dendrogram was prepared
using Average Linkage (between groups). In the study,
10 clones were grouped into 5 clusters at 5 rescaled dis-
tance cluster combine (Figure 2). The constituents of
different clusters were given in Table 4. Cluster 1 and 3
were the largest clusters having 3 clones in each whereas
cluster numbers 2 and 5 have only one clone each. Clus-
ter 5 was the highly divergent from other clusters having
the clone W39.
The mean values of different wood traits for different
clusters are given in Table 5. Cluster 5 showed highest
values for wood traits viz. fiber length, vessel element
diameter and specific gravity and growth parameter viz.
DBH while fiber diameter and specific gravity were
higher in cluster 1. Ramet height was higher in cluster 2.
Lower values were represented by cluster 2 for fiber di-
mensions while vessel dimensions by cluster 4. Lower
specific gravity was shown by cluster 1. Lower growth
traits were represented by cluster 1 (Table 5).
Genetic divergence is most effective tool to identify
the parents for hybridization [22]. Selection for both fe-
male and male parents from two divergent clusters is
important to develop hybrids for new clones. Clusters 2
and 5 were the divergent clusters for male and female
parents respectively. Cluster 2 has one male clone i.e.
W/A 39 which was highly divergent from the clones
clustered in cluster 1 at 4 rescaled distance cluster com-
bine. In the same way, cluster 5 has the female clone W
39 which was divergent from other clones at 5 rescaled
distance cluster combine. Since, clones in cluster 2 and 5
were highly divergent from other clones so used in num-
ber of combinations as parents to develop new hybrids.
These clones can be used for establishing clonal seed
orchard for immediate gain in view of their high diver-
gent nature
Though, clonal strategy is alleged to offer narrow ge-
netic base yet vegetative propagation has strongly rec-
ommended [23-25]. Populus deltoides is propagated
through clones. So development/selection of new clones
in view of their desired wood properties is of utmost im-
portance for the products. In this study, the highly diver-
gent male clone (W/A 39) and female clone (W39) are
important and should be used in number of combinations
for developing new hybrids of desired wood traits to de-
velop new clones.
4. Acknowledgements
I Acknowledge to the Director, Forest Research Institute,
Dehradun (India) for providing necessary facilities dur-
ing the work and Dr. R. C. Dhiman, WIMCO Seedlings
Ltd. Rudrapur, India for providing the material. Author is
also thankful to Mr. G. S. Bisht, Research Assistant,
Wood anatomy Discipline, Forest Research Institute,
Dehradun (India) for laboratory-assistance and Mr. J. N.
Gandhi of WIMCO Seedlings Ltd. Rudrapur (India) for
field assistance.
REFERENCES
[1] H. E. Dadswell, “Tree Growth Characteristics and Their
Influence on Wood Structure and Properties,” Proceed-
ings of 7th British Commonwealth Forestry Conference,
CSIRO, Canberra, 1957, p. 19.
[2] J. Burley and R. R. Palmer, “Pulp and Wood Densitomet-
ric Properties of Pinus caribaea from Fiji,” C.F.I. Occa-
sional Paper No. 66, 1979.
[3] J. M. Dinwoodie, “Tracheid and Fiber-Length in Timber.
A Review of Literature,” Forestry, Vol. 34, 1961, pp.
124-144.

Variations in Wood Properties and Growth in Some Clones of Populus deltoides Bartr. ex Marsh649
[4] B. S. S. Rao and R. V. Rao, “Variation in Length of Ver-
tical Elements within One Tree of Betula pubercens
Ehrh,” Journal of Indian Academy of Wood Science, Vol.
9, No. 2, 1978, pp. 105-110.
[5] P. K. Pande, R. V. Rao, S. P. Agrawal and M. Singh,
“Variation in the Dimensions of Trachied Elements of
Pinus caribaea var. Bahamensis,” Journal of Tropical
Forest Products, Vol. 1, No. 2, 1995, pp. 117-123.
[6] J. E. Phelps, J. G. Isebrands and D. Jowett, “Raw Material
Quality of Short Rotation Intensively Cultured Populus
Clones. A Comparison of Stem and Branches Properties
at Three Species,” IAWA Journal, Vol. 3, No. 3-4, 1982,
pp. 193-200.
[7] A. Kaubaa, A. E. Hernandez, M. Beaudoin and J.
Poliquin, “Interclonal, Intra-Clonal and within Tree
Variationin Fiber-Length of Popular Hybrid Clones,”
Wood and Fiber Science, Vol. 30, No. 1, 1998, pp.
140-147.
[8] L. Chauhan, R. D. Raturi and S. Gupta, “Studies on ana-
tomical variations in different clones of Populus del-
toides,” Indian Forester, Vol. 125, 1999, pp. 526-532.
[9] L. Chauhan, S. Gupta, R. C. Madhwal, R. Pandey and M.
Pal, “Interclonal, Intraclonal and within Tree Variation in
Wood Parameters of Different Clones of Populus del-
toides,” Indian Forester, Vol. 127, No. 7, 2001, pp. 777-
784.
[10] P. Gautam, “Multilocational Trials of Micro-Propa- Gated
L-34 Clone of Populus deltoides Bartr. ex Marsh: Analy-
sis of Wood Anatomical Properties and Growth,” Ph.D
Thesis, Forest Research Institute University, Dehradun,
2010.
[11] P. K. Pande and R. C. Dhiman, “Variations in Wood Tra-
tis in Micro and Macro Propagated Plantation Woods of
Populus deltoides Bartr. ex Marsh,” Advances in Biosci-
ences and Biotechnology, Vol. 1, 2010, pp. 263-275.
doi:10.4236/abb.2010.14035
[12] S. K. Purkayastha, S. P. Agrawal, P. Farooqui, R. D. Tan-
don, L. Chauhan and N. Misra, “Evaluation of Wood
Quality of Eucalyptus Plantations in Various States,” Fi-
nal Technical Report, PL 480 Project no Inn FS-66,
1979-1980, p. 85.
[13] IAWA, “Committee List of Microscopic Features for
Hardwood Identification,” IAWA Bulletin, Vol. 10, 1989,
pp. 201-332.
[14] T. Okuyama, H. Yamamoto, I. Wahyudi, Y. S. Hadi and
K. M. Bhat, “Some Wood Quality Issues in Planted
Teak,” International Conference on Quality Timber Prod-
ucts of Teak from Sustainable Forest Management, KFRI,
Kerala, 2-5 December 2003, p. 21.
[15] R. V. Rao, S. Shashikala, P. Sreevani, V. Kothiyal, C. R.
Sharma and P. Lal, “Within Tree Variation in Anatomical
Properties of Some Clones of Eucalyptus tereticornis
Sm,” Wood Science Technology, Vol. 36, No. 3, 2002, pp.
271-285. doi:10.1007/s00226-002-0139-3
[16] P. K. Pande, “Assessment of the Performance of Different
Clones of Dalbergia Sissoo and Eucalyptus tereticornis
on the Basis of Wood Quality under Different Farm For-
estry Programs,” Final Technical Report, ICFRE, De-
hradun, 2005.
[17] P. K. Pande and M. Singh, “Intraclonal, Inter-Clonal and
Single Tree Variations of Wood Anatomical Properties
and Specific Gravity of Clonal Ramets of Dalbergia sis-
soo Roxb,” Wood Science Technology, Vol. 39, No. 5,
2005, pp. 351-366. doi:10.1007/s00226-004-0273-1
[18] P. K. Pande, “Assessment of the Wood Quality Parameter
in Seed Raised Plantations of Different Diameter Classes
of Dalbergia sissoo Roxb,” FRI-299/Bot-45, FTR sub-
mitted to ICFRE, 2008, pp 120-126.
[19] P. K. Pande, S. Naithani, V. Kothiyal, Mohanta, S. S., N.
Juyal and R. Rawat, “Intra and Inter Tree Variations in
Physico-Chemical and Wood Anatomical Properties of
Leucaena leucocephala (Lam.) De Wit,” Indian Forester,
Vol. 134, No. 5, 2008, pp. 622-632.
[20] W. K. Murphey, T. W. Bowersox and P. R. Blankenhorn,
“Selected Wood Properties of Young Populus Hybrid,”
Wood Science, Vol. 11, No. 4, 1979, pp. 236-267.
[21] R. V. Rao and S. Shashikala, “Assessment of Growth
Rate, Basic Density and Heart Wood Content in Selected
Teak Clones of CSO, Thithimathi in Karnataka State, In-
dia,” International Conference on Quality Timber Prod-
ucts of Teak from Sustainable Forest Management, KFRI,
Kerala, 2-5 December 2003, p. 57.
[22] G. M. Bhatt, “Comparison of Various Methods of Select-
ing Parents for Hybridization in Common Bread Wheat
(Triticum aestivum),” Australian Journal Agriculture Re-
search, Vol. 24, No. 4, 1973, pp. 457-484.
doi:10.1071/AR9730457
[23] E. Camphinhos and Y. K. Ikemori, “Mass Production of
Eucalyptus Species by Rooting Cuttings,” Proceedings
IUFRO symposium Genetic Improvement and Production
of Fast Growing Trees, Sao Pede Sao Paulo, 1980, p. 16.
[24] M. R. Ahuja and W. J. Libby, “Clonal Forestry I: Genet-
ics and Biotechnology,” Springer-Verlag, New York,
1993 a, p. 227.
[25] M. R. Ahuja and W. J. Libby, “Clonal Forestry II: Genet-
ics and Biotechnology,” Springer-Verlag, New York,
1993 b, p. 240.