American Journal of Plant Sciences, 2011, 2, 370-374
doi:10.4236/ajps.2011.23042 Published Online September 2011 (http://www.SciRP.org/journal/ajps)
Copyright © 2011 SciRes. AJPS
Rejuvenation and Adventitious Rooting in
Coppice-Shoot Cuttings of Tectona grandis
as Affected by Stock-Plant Etiolation
Azamal Husen
Department of Biology, Faculty of Natural and Computational Sciences, University of Gondar, Gondar, Ethiopia.
Email: adroot92@yahoo.co.in
Received February 8th, 2011; revised April 25th, 2011; accepted July 5th, 2011.
ABSTRACT
The effect of stock-plant etiolation on adventitious rooting of single-node leafy cuttings (SNCs) made from coppice
shoots from different age groups of donor plants were investigated for teak (Tectona grandis Linn. f.). When donor
plants age were 1-, 2-, 3-, 4-, and 5-year-old, they were coppiced and maintained in the dark for etiolation, while a
parallel set was kept in normal light in an open environment. After 20 days, coppice shoots were made into SNCs which
were cultured under intermittent mist for rooting. Stock-plant etiolation significantly increased percent rooting, shoot
and root length, and number of roots per SNC, but callusing at the base of SNCs decreased. Etiolated SNCs have shown
71.7% rooting, whereas for controls (non-etiolated), the response was 41.7%. The effect of aging on callusing, rooting
and sprouting of etiolated and non-etiolated coppice shoots cuttings varied widely. Aging of donor plants decreased
rooting and sprouting capability in SNCs and increased callusing at the base of etiolated cuttings. The results showed
that stock-plant etiolation in 1-, 2-, 3-, 4-, and 5-year-old donor plants hastened rooting potential by rejuvenation of
coppice shoots.
Keywords: Adventitious Rooting, Cuttings, Etiolation, Maturity, Tectona grandis
1. Introduction
Teak (Tectona grandis Linn. f.) is considered as the no-
blest among all woods not simply because of its golden
hue and wonderful texture, but even more because of its
durability. This species grows naturally in India, Myan-
mar, Laos and Thailand, and it is naturalized in Java,
Indonesia, where it was probably introduced some 400 to
600 years ago [1]. In addition, it has been established
throughout tropical Asia, as well as in tropical Africa
(including Côte d’Ivoire, Nigeria, Sierra Leone, the
United Republic of Tanzania and Togo), Latin America
and the Caribbean (Costa Rica, Colombia, Ecuador, El
Salvador, Panama, Trinidad and Tobago and Venezuela);
and introduced in some islands in the Pacific region
(Papua New Guinea, Fiji and the Solomon Islands) and
in northern Australia at trial levels [1]. Generally, root-
shoots/stumps and seeds are used as a planting material
in teak plantations. The root-shoot/stumps are prepared
by cutting one-year-old healthy seedlings into 15 - 0 cm
root and 2.5 cm shoot portion with more than 1.0 cm
thickness [2]. Quality teak stumps can be produced from
seeds collected from identified best seed sources, such as
seed production areas and seed orchards [2]. However,
the seed yield per tree is low, and only few seedlings are
produced per 100 seeds [3]. Therefore, propagation through
cuttings has been widely used to multiply the elite teak
trees obtained from the natural population to exploit the
genetic variability [4]. Cutting loss of rooting potential
with stock plant age/or maturation is studied for many
forest tree species [5-8]. Attempts have been made to
understand and improve the adventitious rooting effi-
ciency of cuttings in selected plant species including teak
because various intrinsic as well as extrinsic factors are
responsible for adventitious root formation [9-17]. Among
these factors, manipulation of stock plants via exposure
to darkness for etiolation was used to improve the rooting
status of stem cuttings. Reports have shown that stock-
plant etiolation increased adventitious root formation by
a number of different taxa including teak [10,15,18-21].
Various anatomical, physiological and molecular changes
were found to be associated with enhanced rooting effi-
ciency in etiolated stem tissues [15,18-21]. To date, with
reference to rooting of teak cuttings on the relationship
Rejuvenation and Adventitious Rooting in Coppice-Shoot Cuttings of Tectona grandis 371
as Affected by Stock-Plant Etiolation
between stock-plant etiolation and aging of donor plants
is unknown. Therefore, the present study focuses on
whether etiolation and maturation/or aging can affect on
adventitious rooting capacity of coppice shoots single-
node leafy teak cuttings.
2. Methodology
2.1. Experimental Site
The experiments were conducted at the Plant Physiology
nursery of New Forest campus, Forest Research Institute
(FRI), Dehra Dun, India. The FRI campus is located in
the Doon valley, and is surrounded by Western Lesser
Himalayan ranges in the north and Shiwalik ranges in the
south. This campus covers an area of 4.5 km2, and lies at
an elevation of 640.08 m above mean sea level. It is situ-
ated on North Latitude 30˚20'40" and East Longitude
77˚52'12" on the northern limit of the Oriental region.
2.2. Donor Plants and Stock-Plant Etiolation
Regularly at different time intervals (1998-2003), the
donor plants were raised in nursery beds using seeds col-
lected from teak (clone FG1) seed orchard of New Forest
campus, FRI. They were maintained by regular watering
and weeding. Complete protection was provided against
diseases and insects by foliar spray with insecticides and
fungicides, as and when required. From these stock plants
five aged group of donor plants were chosen, namely 1-,
2-, 3-, 4-, and 5-year-old. The seedlings in each age
group donor plants were severed in June 2003, so that the
stem retained only three basal nodes (i.e. stock plant),
and they were divided into two groups. Coppicing was
performed considering that stem will produce more cop-
pice shoots. It is an established fact that coppicing re-
sulted in cutting back the plants to more ontogenetically
tissue, although the oldest teak seedlings were 5-year-old.
Thereafter, the first group (1-, 2- 3-, 4-, and 5-year-old
stock plants) was maintained under natural light (i.e.,
control) in an open environment, while the second group
(1-, 2-, 3-, 4-, and 5-year-old stock plants) was kept in
the dark for etiolation.
2.3. Rooting Trials
After 20 days, rooting trials were conducted using about
4.0 cm long leafy coppice shoots obtained from etiolated
and non-etiolated stock plants of each age group. Cop-
pice shoots were used for the preparation of single-node
leafy cuttings (SNCs). SNCs used for this experimenta-
tion were obtained from the basal portion of coppice
shoots. Coppice shoots obtained from etiolated and non-
etiolated stock plants were divided into ten sub-groups of
50 SNCs each, and they were belonged to 1-, 2-, 3-, 4-,
and 5-year-old donors. All SNCs were treated with 0.05%
(w/v) bavistin for 30 min. The cuttings were inserted into
sterilized vermiculite (pH 7.0) pre-soaked in water for
24h. Then these leafy cuttings were cultured in the trays
and incubated in a mist chamber. Automatic misting cy-
cle was set at 60 s on and 1h off duration in day, while
during the night it was 30 s on and 1h off duration. Inside
the mist chamber, the RH was maintained at 85% ± 2%,
and maximum and minimum day/night temperature were
32˚C ± 10˚C and 26˚C ± 10˚C, respectively. After 50
days, the cuttings were carefully removed from the root-
ing medium, and observations were made on percent
callusing, percent sprouting, percent rooting, number of
shoots and their length (cm), number of leaves per cut-
ting, and number of roots per cutting and their length
(cm).
2.4. Statistical Analysis
The experiment was conducted in a randomized block
design, involving two light conditions (control, i.e., na-
tural light and etiolation) and five aged groups of donor
plants (1-, 2-, 3-, 4-, and 5-year-old). Five replications
were used, with ten SNCs per replication. Prior to statis-
tical analyses, all percent data were transformed into arc
sin square roots and the data were analyzed by two-way
analyses of variance. Comparisons between the mean
values were made by the least significance difference
(LSD test) at P < 0.05. The SPSS/PC software Ver. 16.0
was used to process all the data.
3. Results
Results showed that stock-plant etiolation significantly
decreased callusing at the base of SNCs. It was 20% for
non-etiolated SNCs as compared to 6.7% of the etiolated
cuttings (Table 1). Age of donor plants exhibited sig-
nificant remarkable variation in the formation of callus in
SNCs. Percent callusing was absent in coppice-shoot
cuttings of 1-, 2-, 3-year-old donors. However, callusing
of cuttings was 3.3% and 10% for 4-, and 5-year-old do-
nors, respectively (Table 2). Rooting percentage was
higher for SNCs (71.7%) obtained from etiolated stock
plants than those from (41.7%) non-etiolated stock plants.
Mean root length and number of roots per SNC was also
more in etiolated stock plants as compared to non-etio-
lated stock plants (Table 1). With increasing age of do-
nor plants, rooting efficiency in terms percent rooting,
mean root length and number of roots per SNC declined
significantly. Highest (78.2%) rooting percentage was
recorded in 1-year-old donors, whereas it was lowest
(53.3%) in 5-year-old donors (Table 2). Stock-plant etio-
lation caused an increase in percent sprouting, 48.3% of
the non-etiolated SNCs sprouted, as compared to 73.3%
Copyright © 2011 SciRes. AJPS
Rejuvenation and Adventitious Rooting in Coppice-Shoot Cuttings of Tectona grandis
as Affected by Stock-Plant Etiolation
Copyright © 2011 SciRes. AJPS
372
of the etiolated cuttings. Further etiolation significantly
enhanced number of shoots and leaves per SNC, and
mean shoot length per SNC (Table 1). However, aging
of donor plants caused a significant decrease in percent
sprouting. SNCs obtained from 1-year-old donors sprouted
the most (78.2%), whereas it was lowest in 5-year-old
donors (56.7%). The results further showed that aging of
donor plants significantly decreased number of leaves per
SNC (Table 2). Significant interactions (P 0.05) be-
tween light condition and age of donor plants were ob-
served for percent callusing, root length and number of
roots per SNC (data not shown).
4. Discussion
The present study showed that aging and stock-plant
etiolation caused a decrease in callus formation at the base
of coppice-shoot cuttings. Previous studies have shown
that a reduction in callus formation is beneficial for root-
ing by shoot cuttings [7,8] because increased callusing
has been observed to be associated with unfavorable
auxin-nutrient (sugar) balance in meristematic cells in the
rooting zone [8,22,23]. Single-node leafy coppice-shoot
Table 1. Effect of etiolation on root and shoot parameters of coppice-shoot single node cuttings from Tectona grandis seed-
lings.
Rooting parameters
Light conditiona
% callusingb % rootingb % sproutingbShoots/cutting Shoot length
(cm) Leaves/cutting Roots/cutting Root length
(cm)
Control 20.00 (18.77) 41.67 (38.54) 48.33 (45.59)0.76 3.33 3.00 1.65 4.79
Etiolation 6.67 (7.05) 71.67 (63.16) 73.33 (66.50)1.00 4.27 3.60 3.50 6.98
LSD0.05 10.50* 13.33* 15.17* 0.12* 0.47* 0.31* 0.42* 0.96*
aThe stock plants represent the stumps with three basal nodes coppiced from 1-, 2-, 3-, 4- and 5-year-old donor plants; they were etiolated in the dark for 20
days, while the control stumps were maintained under natural light in an open environment; bFigures within parenthesis represent arc sin square root trans-
formed values; * = significantly different from the control at P 0.05, according to F-test.
Table 2. Effect of aging on root and shoot parameters of coppice-shoot single node cuttings from Tectona grandis seedlings.
Rooting parameters
Age of
donor plants
% callusinga % rootinga % sproutingaShoots/ cuttingShoot length
(cm) Leaves/ cutting Roots/ cutting Root length
(cm)
1-year 0.00 (1.28) 78.16 (71.24) 78.16 (71.24)1.00 3.60 5.12 2.96 7.16
2-year 0.00 (1.28)) 73.33 (66.50) 73.33 (66.50 1.00 3.63 5.00 2.90 7.00
3-year 0.00 (1.28) 70.00 (61.40) 70.00 (61.40)1.00 3.54 3.60 2.80 6.54
4-year 3.32 (3.52) 63.33 (53.03) 66.67 (58.51)1.00 3.46 2.40 2.70 6.11
5-year 10.00 (10.57) 53.33 (48.51) 56.67 (52.03)0.90 3.42 2.20 1.90 4.69
LSD0.05 7.80* 18.85* 18.01* ns ns 0.81* 0.59* 1.36*
aFigures within parenthesis represent arc sin square root transformed values; * = significantly different from the control at P 0.05, according to F-test; ns =
non-significant at P 0.05, according to F-test.
Rejuvenation and Adventitious Rooting in Coppice-Shoot Cuttings of Tectona grandis 373
as Affected by Stock-Plant Etiolation
cuttings obtained from etiolated stock plants rooted and
produced the most shoots. However, coppice-shoot cut-
tings obtained from non-etiolated stock plants formed
roots and shoots, 41% and 48%, respectively. The en-
hanced rooting efficiency is probably due to high sugar
content in etiolated coppice-shoot cuttings, and possibly
due to increased mobilization of carbohydrates from
starch [18,19]. These changes might be beneficial for
adventitious root primordium development in shoot cut-
tings. Sugar content was previously found to be posi-
tively correlated with rooting efficiency of teak cuttings
[12,18,23,24]. An increase in sugar content of etiolated
shoot cuttings was associated with profuse rooting [18,
22-24]. In addition, specific classes of flavonoid com-
pounds may act as an auxin transport inhibitors [25].
Flavonoid biosynthesis is regulated by light. Although
flavonoids are not accumulated in dark-grown seedlings,
they are rapidly produced in response to light [26]. In the
coppice-shoot cuttings of etiolated stock plants, the
highest rooting response and shoot growth may perhaps
be due to an inhibition of flavonoid biosynthesis. Fur-
thermore, anthraquinones were established as a reliable
marker for juvenility and maturity in teak [18,23]. An-
thraquinones in coppice shoots obtained from etiolated
and non-etiolated stock plants showed that etiolation re-
stored some chemical features of juvenile shoots associ-
ated with enhanced rooting [18,23]. Similarly, in the
present study coppice-shoot cuttings obtained from the
etiolated stock plants have shown enhanced rooting, in-
dicating that etiolation caused juvenility in teak. Overall,
the beneficial effects of etiolation on rooting and shoot
growth were reported in a number of taxa including teak
[10,15,18-21]. In this study, both rooting and sprouting
by coppice-shoot cuttings declined with increasing age of
donor plants. Decreased rooting potential of cuttings due
to aging/or maturity of donor plants has been previously
reported in several plant species [6-8,10,28-30] which
may be due to decreased sensitivity of aging tissues to
rooting promoters or accumulation of inhibitory sub-
stances for rooting and/or decrease in the content of en-
dogenous auxins responsible for root formation by cut-
tings [7,8,31]. In conclusion, the studies hitherto made to
examine rooting response of etiolated vis-à-vis non-etio-
lated teak cuttings from coppice-shoot obtained from 1-,
2-, 3-, 4-, and 5-year-old donors. Stock-plant etiolation
treatment increased rooting performance in coppice shoot
cuttings of all age groups of donor plants, and etiolation
treatment appears to rejuvenate teak stock plant, resulting
in profuse rooting response.
5. Acknowledgements
This work was supported by World Bank Forest Re-
search Education and Extension Programme (FREEP)
and Indian Council of Forestry Research and Education
(ICFRE), Dehra Dun, India.
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