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In vitro multiplication of an industrial fiber
plant kenaf (Hibiscus cannabinus L.)  
ARBAOUI Sarraa, CAMPANELLA Brunob, ROGER Paulb
and BETTAIEB Taoufika
Horticultural Science laboratory, National
Agronomic Institute of Tunisia 43 Charles Nicolle
Street, 1082 Tunis Mahragene, Tunisia b
Environmental Toxicology laboratory, Gembloux Ago
Bio Tech 2, Passage de Déportés, 5030 Gembloux,
Belgium saraharb_at_hotmail.fr

Introduction Kenaf (Hibiscus cannabinus L.) is an
annual fiber plant of Malvacea family. The stem
produces two types of fiber, a coarser fiber in
the outer layer and a finer fiber in the core.
It has been cultivated for the manufactures of
ropes, textiles, paper, insulation and used in
many industries including automobile industry.
Problems encountered in the establishment of
uniform, vigorously growing kenaf result from
seed germination quality. The purpose of this
study was to develop a suitable protocol for
micropropagation of kenaf.
Materials and Methods Plant materials consisted
of 10 cm nodal microcutting excited from shoots
of plants aged 50 days. Tests for the first
culture phase (4 weeks) were conducted on basal
Murashig and Skoog (1962) MS medium supplemented
with 5 IBA (indolebutyric acid) concentrations
(0 0,25 0, 5 1 2 mg.l-1) and 5 BAP (benzyl
adenine) concentrations (0 0, 25 0, 5 1 2
mg.l-1). Rooting tests were conducted, during 4
weeks, on MS media supplemented with 3 IBA
concentrations (0 0,25 0,5 mg.l-1). Growth
parameters data were submitted to analysis of
variance (ANOVA) using SAS program. The
differences among means were analyzed by Student
test at 5 significance level.

• Results
• Initiation of in vitro culture
• Initiation of in vitro culture is 100 in all
  culture media
• The highest number of nodes is obtained on the
  MS medium supplemented with 0.25 mg.l-1 BAP and
  0.5 mg.l-1 IBA
• Table 1 Effect of plant growth on nodes
  formation, shoot induction () and growth

Medium Plant growth regulator combinations (mg/l) Shoot induction () Number of shoots Number of nodes Shoot length (cm) Rooting ()
0 MS 100 1.38 ab 2.22 ab 1.67 ab 66.66
1 MS 0.25 BAP 100 1.22 b 1.82 ab 1.13 b 44.44
2 MS 0.25 IBA 100 1.30 ab 1.15 c 0.85 c 40
3 MS 0. 5 BAP0.25 IBA 100 1.22 b 1.82 ab 1.23 b 11.11
4 MS 0.25 BAP0.5 IBA 100 1b 3.17 a 2.67 a 100
5 MS 1 BAP 0.25 IBA 100 1.44 a 1.85ab 1.85 ab 28.57
6 MS 0.25 BAP 1 IBA 100 1.6 a 2.56 ab 2.66 a 70
7 MS 2 BAP 100 1.2 b 1.2 c 0.68 c 0
8 MS 2 BAP0.25 IBA 100 1.2 b 1.4 b 0.52 c 0
9 MS2 IBA 100 1.1 b 1.6 b 1.37 b 100
Multiplication
Microcuttings
Rooted vitroplants
Acclimatized vitroplants
- Means of the same column followed by different
letters are significantly different at Plt 0.05
according to Student Test. - Conditions of the
test Photoperiod 16 hours. Light Intensity 36
µmol.m-2.s-1. Temperature 23 ? 1C. Culture
period 4 weeks.  
In vitro rooting - In vitro rooting tests led to
a general rooting in shoots cultivated in
different treatments. - The highest number of
roots was obtained with growth regulators free
medium and medium supplemented with 0.25 mg/l of
IBA. - The longest roots were obtained with
medium without growth regulators. - The exogenous
supply of IBA does not improve rooting.
Multiplication - The highest number of formed
nodes 3.8 was obtained for MS control medium. -
MS medium free growth regulators appeared to be
the best medium for shoot induction. - Root
induction was simultaneously observed along with
shoot elongation.
Table 2 Effect of IBA Concentration on root
induction () and length
IBA (mg.l-1) Rooting () Number of roots Root length (cm)
0 100 8.67 a 1.93 a
0.25 100 8.66 a 1.46 b
0.5 100 5.50 b 1.29 b
Acclimatization The kenaf plants show no ex
vitro adaptation problem. The success rate of
transplanted plants was 100.
Conclusion An efficient micropropagation method
has developed to initiate shoots and regenerate
plants of Hibiscus cannabinus L. in a relative
short time and high multiplication rate. The use
of MS medium added with 0.25 mg.l-1 BAP and 0.5
mg.l-1 IBA stimulate shoot induction and nodes
formation on the first in vitro culture step.
During multiplication stage, MS free growth
regulators was the best media for explant growth.
In vitro micropropagation of kenaf does not
require any additional rooting step regarding to
its easy rooting aptitude. Rooted plant can
growth to maturity and produce seed under open
pollinated conditions.