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					Propagation of Plants
  by Stem Cuttings

      Module 3
Stem cutting propagation

To induce the development of an
 ADVENTITIOUS root system:
An adventitious root is a root which
 arises from a plant organ other than
 another root:
Stem cutting propagation is normally
 only possible with dicotyledonous
 plants:
Types of stem cuttings
 Deciduous plants

 Softwood cuttings
 Semi-ripe cuttings
 Hardwood cuttings
Types of stem cuttings
 Evergreen plants:

 Softwood cuttings
 Semi-ripe cuttings
 Ripe evergreen
  cuttings
 Conifer cuttings
Deciduous plants
Softwood cuttings:
Cuttings taken as early as possible as
 the shoot grows:
Cuttings are taken from soft, succulent
 stems with no trace of lignification:
Softwood cuttings will be subject to
 rapid dessication:
A high humidity propagation facility will
 be required; mist or fog:
Softwood cuttings
 With deciduous
  plants the growth
  cycle is related to
  seasonal
  development:
 Softwood cuttings
  are available in
  spring:
 Azalea, Abelia
Semi-ripe stem cuttings
 With these cuttings,
  the collection is
  delayed until the
  commencement of
  lignification:
 The cuttings are
  firmer and the need
  for a highly
  controlled
  environment is
  lower
Semi-ripe stem cuttings
 Fog or mist facilities
  can be used:
 Semi-ripe cuttings
  can be propagated
  in low cost facilities:
 Plastic tents:
 Cold frames:
 Sun tunnels:
Deciduous hardwood stem cuttings

 Cuttings taken at
  end of growing
  season:
 Dormant, leafless
  cuttings:
 Length 180–200 mm
 Can be propagated
  outdoors with no
  protection:
Deciduous hardwood stem cuttings

 When propagating
  trees, the cutting is
  buried to its full
  depth in the soil:
 Only the top bud is
  allowed to grow:
 With shrubs, the
  cutting is buried to
  half its length:
Ripe evergreen cuttings
 Cuttings taken from
  fully ripe shoots of
  stock plant:
 With evergreen
  plants there can be
  several growth
  flushes per year:
 At the end of each
  growth flush,
  cuttings can be
  used:
Ripe evergreen cuttings
 Ripe evergreen
  cuttings have
  mature leaves:
 However,
  transpiration is very
  low and cuttings
  can be raised in low
  cost facilities, or
  outdoors in full sun:
Conifer cuttings
 Usually taken from
  mature shoots at the
  onset of winter:
 They are often taken
  with a heel of older
  growth:
 Propagate under fog
  or mist:
 Very slow to root:
Herbaceous cuttings
 Soft, succulent tips
  of new shoots are
  taken early in
  spring:
 As soon as stem
  length is long
  enough:
 High humidity
  essential:
 Avoid flowering
  stems:
Sources of propagation material
 3 sources used:

 From sales stock
  which will be sold:
 From outside
  sources:
 From stock plants:
Collection from sales stock
 Can fulfill a useful
  pruning role:
 The genetic identity
  is known:
 Nutrition not ideal:
 Time consuming:
 Danger of excessive
  removal of shoots:
 Needs good
  communication:
Collection from outside sources
 Eg parks and
  gardens:
 Genetic uncertainty:
 Unknown pathogen
  status:
 Unknown nutrition:
 Quarantine risk:
 Standard fungicide
  treatment:
                         A beautiful form of Waratah in a park
Establishment of stock plants
 Stock plants may be
  held in containers:
 Or planted in the
  field:
 Plant close together
  and prune to a
  hedge:
 Trim back regularly:
 Easy to collect
  cuttings:
                         Sturts Desert Pea stock plants
Timing of propagation
Some plants can be propagated easily
 at all growth stages – Westringia:
Others can only succeed at one
 particular stage of growth – conifers:
In designing a propagation program,
 the needs of the difficult to propagate
 types must have precedence:
The easy types can be fitted in as
 space becomes available:
Wounding of stem cuttings

With ripe evergreen and conifer
 cuttings, it can be difficult for roots to
 emerge:
The physiological aging process can
 produce a row of densely packed cells
 immediately under the bark:
This barrier prevents root emergence:
Many cuttings just don’t root:
Wounding of stem cuttings

Wounding involves removing a thin
 slice of tissue from one or two sides of
 the base of the stem:
A sharp knife is essential:
Removal of the cell barrier allows the
 roots to emerge:
Softwood cuttings do not need
 wounding:
Application of hormone treatments
 The main group of
  hormones involved
  in root formation are
  the AUXINS:
 Auxins are
  synthesised
  naturally in the
  apical regions of
  stems:
 Difficult cuttings
  may be lacking in
  auxins
Types of auxins used in propagation

 3 main types used:

 Indole acetic acid
  IAA
 Indole butyric acid
  IBA
 Naphthalene acetic
  acid NAA
Commercial auxins

Externally applied auxins are beneficial
 if:
Used in the correct concentration:
Fresh preparations must be used:
Stored out of direct sunlight:
Combinations of two types may be
 beneficial: Equal parts of IBA and NAA
 are often recommended:
Commercial formulations available
 Four formulations
  are available:
 Powder formulation:
 Dilute solution:
 Concentrated
  solution:
 Gel formulation:
Powder formulation
 The powder carrier is
  usually talcum:
 Inert coloured dyes are
  used to denote
  concentrations:
 Available in a range of
  strengths to suit cutting
  maturities:
 A variable amount of
  materials adheres to the
  base of each cutting:
Dilute Solution
 An old fashioned
  style:
 A low concentration
  solution in which
  cuttings may be
  dipped for several
  hours:
 Only suitable for
  ripe cuttings:
 Not widely used:
Concentrated solution
 2000 – 8000 mg/L:
 Aqueous solution:
 Alcohol based
  solution:
 Quick dip 1-5
  seconds:
 Excessive time may
  cause tissue
  burning:
Gel formulations
 The auxin carrier is
  a stiff gel:
 When the cutting is
  dipped in the gel a
  blob of gel adheres
  to the base of the
  cutting:
 “Muck and Magic”
  gel preparations:
Cutting production systems
 Community tray
  propagation:
 Individual cell
  propagation:
 Direct sticking in
  tubes:
 Direct sticking in
  sales containers:
Ultra-soft cutting propagation
My interest in this potential system of
 cutting propagation was stimulated by
 our program of tissue culture
 propagation:
Plantlets produced in tissue culture
 exhibit strong apical dominance:
This means that the plants deflasked in
 tubes exhibit a strong, single stem
 habit of growth:
Ultra-soft cutting propagation

In order to produce a tube with a bushy
 habit of growth, it is necessary to tip
 prune the apical shoot:
I thought there would be potential in
 using these soft tips as cuttings:
I have achieved considerable success
 with a range of ultra-soft cuttings of
 perennials and soft-stemmed shrubs:

				
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posted:2/11/2012
language:English
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