Introduction
Deschampsia antarctica Desv. (Poaceae) is the only native
Gramineae found in the Antarctic, where it is restricted to
the Antarctic Peninsula and its offshore islands. Its ability to
survive the harsh climate has attracted the interest of
scientists searching for genes associated with freezing
tolerance (Alberdi et al. 2002). For continuing research
purposes it would be better if plants did not have to be
collected from the field, but could be propagated effectively
to provide the necessary experimental material D. antarctica
normally reproduces both by seed produced by self-
fertilization and also vegetatively from tillers (Holderegger
et al. 2003). Vegetative propagation is slow and unable to
generate enough plant material for laboratory requirements.
This difficulty prompted us to develop a rapid micro-
propagation method using tissue-culture methods for the
production of large numbers of plants in relatively short
periods.
We describe here a method for the rapid micropropagation
of D. antarctica that can solve the problem of availability,
and prevent excessive collection from its natural habitat.
Materials and methods
Deschampsia antarctica was collected in the Coppermine
Peninsula on Robert Island, South Shetland Islands during
January 2001 and propagated vegetatively in soil:peat
mixture (3:1) at 13°C ± 2°C in a growth chamber (Forma
Scientific Inc, Marietta, OH, USA) with photon flux density
of 180 umol m
-2
s
-1
at the top of canopy and 21/3 h
light/dark period (start material).
After four months the plants were thoroughly washed to
eliminate all substrate, and surface sterilized for 20 min in
Erlenmeyer flasks with 300 ml of an aqueous suspension of
1.5 g l
-1
Captan 80W (BASF Chile-SA) and 0.5 gl
-1
Benomyl 500WP (CYANAMID Chile-SA), under constant
stirring, and then rinsed three times with sterile distilled
water. The plants were transferred to 300 ml of 15% sodium
hypochlorite and 0.01% Tween 20 for 20 min, and then
rinsed three times with sterile distilled water.
The explants (5 mm) with a portion of crown tissue and
roots were excised from the sterile plants (Fig. 1a & b),
placed horizontally in Petri dishes (15 x 90 mm; 20 explants
per plate), and incubated in the dark on MS basal medium
(pH 5.8 ± 1, 25 ± 2°C) containing 3% sucrose (w/v), 0.9%
agar (w/v), and one of five different concentrations of 2,4-D
and BAP growth regulators (Table I). When shoots were
larger than 0.5 cm (after 30–60 days of incubation,
depending on the hormone concentrations used), the
calluses were subdivided.
The shoots were incubated in culture bottles in the same
MS medium without hormones under 16/8 h light/dark.
After as little as 15 days the multiplication of plants was
begun, being repeated three times, each time with 15
replicates for each hormone concentration. After this, the
plants were planted in soil: peat mixture in the same
conditions as the donor plants. To determine if regenerated
plants were genetically different, we used the Amplification
Fragments Length Polymorphism (AFLP) assay. DNA was
extracted with the high molecular weigh DNA extraction kit
"GenElute Plant Genomic DNA Kit" (SIGMA), according
to the manufacturer's instructions. The AFLP reaction was
performed according to the manufacturer's instructions
(GIBCO-BRL, Life Technologies). The AFLP products
were separated by electrophoresis in polyacrilamide/urea
(6%/8M) gels in 0.5% TBE buffer and 1800 v by 2 h. For
non-radioactive visualization, we used the Silver
Sequence
TM
DNA Sequencing System Kit (Promega).
Results and discussion
After two weeks of culture under different hormonal
treatments (Table I), cicatricial callus was observed around
Antarctic Science 17 (1): 69–70 (2005) © Antarctic Science Ltd Printed in the UK DOI: 10.1017/S0954102005002440
69
Short Note
Micropropagation of Deschampsia antarctica - a frost-resistant
Antarctic plant
MARELY CUBA, ANA GUTIÉRREZ-MORAGA, BARBARA BUTENDIECK and MANUEL GIDEKEL*
Laboratorio de Fisiología y Biología Molecular Vegetal, Instituto de Agroindustria, Facultad de Ciencias Agropecuarias y Forestales,
Universidad de La Frontera, Casilla 54-D, Temuco, Chile
*corresponding author: mgidekel@ufro.cl
Received 28 April 2004, accepted 18 August 2004
Table I. Callus and shoot response of D. antarctica cultured in MS
medium containing different 2,4-D and BAP growth regulator
combinations.
2,4D BAP Callus Shooting Shoots/Callus
Treatment* (μM) (μM) formation (%) response (%) (mean ± SD)
1 2.2 - 100 98 22.7 ± 1.3
2 2.2 0.2 100 99 25.4 ± 1.9
3 4.5 2.0 90 85 10.3 ± 1.0
4 4.5 4.0 84 80 7.8 ± 1.1
5 9.0 4.0 58 35 5.3 ± 2.8
Control - - 0 65 15.6 ± 0.9
*All hormonal combinations were in MS medium.