Poplar tissue culture - National Centre for Biotechnology Education

PRACTICAL
BIOTECHNOLOGY
Poplar
tissue culture
PLANT TISSUE CULTURE experiments in school are often a
problem: either the plant tissue is insufficiently sterilized, or for some
reason the tissue just refuses to grow. This is compounded by the high
cost of both the tissue culture medium and plant growth substances,
and the inordinate length of time it takes to prepare everything. Here’s
a practical which overcomes all of these difficulties. It requires neither
aseptic conditions or expensive growth media.
Materials
Freshly-sprouted twigs from poplar trees
(Populus sp.)
Aqueous solution of kinetin, about 1 cm 3
Make up a concentrated stock solution of kinetin
in distilled water, then dilute this further to
obtain 0.002 g per litre. Kinetin does not
dissolve readily in water unless the solution is
made alkaline using, for example, a few pellets
of sodium hydroxide.
9 cm diameter discs of Whatman No.1
filter paper, 2–3
Clean Petri dish
Adhesive tape or Parafilm
Sharp knife or scalpel
Petri dish and wet them thoroughly with the
kinetin solution.
3. Place the twigs, cut surface uppermost, on the
filter paper.
4. Replace the Petri dish lid and secure it well,
but not over-zealously, around the rim with
adhesive tape. The aim is to reduce
evaporation of the kinetin solution, without
making it difficult to remove the lid to replenish
the solution at intervals as necessary.
5. Keep the Petri dishes in a warm, well-lit place.
Examine them at weekly intervals. After a few
weeks callus tissue will form. Buds may also
grow shortly after this.
6. If mould appears on the uppermost filter paper,
just slip it out from under the twigs using
forceps, leaving the uncontaminated paper
discs below.
7. Should the filter paper begin to dry out, simply
re-wet it with distilled water.
Safety
Plastic gloves should be worn whilst handling kinetin
powder. Spills of kinetin should be washed up
promptly, using plenty of water.
Practical details
Further activities
1. Cut internodal lengths of poplar twigs about 1–2
cm long, and split them lengthwise using a sharp
knife or scalpel.
2. Put 2–3 filter paper discs into the base of the
Students could investigate the effect of light, the
concentration of kinetin, interaction with other plant
growth substances (such as IAA) or the use of
different plant species.
ADDITIONAL
INFORMATION
This investigation
was suggested in
Experiments in plant
tissue culture
(Second Edtn) by
John Dodds and
Lorin Roberts
(1985) Cambridge
University Press.
ISBN: 0 521 31516 6.
It has been adapted
for schools use by
John Schollar at the
NCBE.

Poplar tissue culture
1. Split the poplar twigs lengthways
(a scalpel is more convenient than
an axe for this task).
2. Put two or three pieces of filter
paper into a Petri dish and
moisten them with
kinetin solution.
3. Place the split twigs (cut surface
uppermost) onto the moistened
paper.
4. Seal the Petri dish
lid loosely, with
sticky tape.
(Don’t fix the lid on too
firmly, as you may wish
to water the twigs from
time to time.)
5. Keep the Petri dish in a warm, light place.
Cartoon by Colin Brown
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© National Centre for Biotechnology Education, 1995