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SEXUAL PLANT PROPAGATION
DEFINITION

Propagation-to reproduce or increase in number
TYPES OF PROPAGATION:
Sexual
 Uses seeds
 Requires the union of pollen (male sex cells)
and egg (female sex cell) in the ovary
 Asexual
 Produces exact duplicates of the plant
 Uses part of the plant, such as leaf, stem, or
root
 Asexual propagation is possible because each
individual cell of a plant has all characteristics
of the entire plant and can re-grow missing
parts

PROPAGATION FROM SEEDS:

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Benefits
 Quick
 Inexpensive
 Easy
Special requirements
 Scarification-weakening of the hard seed coat
Ex: sandpaper, scratching or acid bath
 Cold shock-moist, cold rest period for 8 weeks or
longer
 Light
 Darkness
**Therefore, always follow the planting
instructions**
COMPOSITION OF SEEDS:
Seed coat
 Outside covering that protects the embryonic
plant
 Makes transportation and storage possible
 Endosperm
 Stored plant food
 The first start of growth in a seed
 Embryo (embryonic plant)
 New plant that is developed as a result of
fertilization
 Extends root and seed leaves to form a new
plant

WHAT’S NEEDED FOR GERMINATION?
Temperature
 Moisture
 Air
 Light or absence of it

PROCESS OF GERMINATION
Seed absorbs water
 Seeds proteins activated
 Radicle (root) emerges
 Plumule or embryonic shoot emerges
 Leaves form and food production begins

MONOCOT SEEDS
Seed coat-protection
 Endosperm-a source of energy
 Embryo-miniature plant that has:
 Epicotyle-shoot above cotyledon
 Hypocotyl-part of stem below the cotyledon
 Radicle-primary root, supports seedling

MONOCOT GERMINATION
Seed swells
 Radicle grows down
 First internode and epicotyl grows upward
 New leaves form and food production starts
 New root system develops
 Temporary root system ceases to function and
dies

DICOT SEEDS
Seed coat-protection
 Embryo-miniature plant
 2 cotyledones-seed leaves
 Epicotyl-true leaves
 Hypocotyl-first stem, pulls seed upward
 Radicle-forms roots

DICOT GERMINATION
Seed swells
 Radicle grows down
 Hypocotyl forms arch that breaks soil surface
 Hypocotyl reaches light and straightens up
 Cotyledons turn green and make food
 As new leaves develop, cotyledons dry up and fall
off

SEEDING
SELECTION OF SEEDS:
Identify seeds grown locally
 Check germination ability
 Purchase from a reliable dealer
 Chose hybrid varieties for greater vigor,
uniformity, and flowering ability
 Select uniform heavyweight or primed seeds

IMPROVING GERMINATION OF SEEDS:
Sorting
 Seed quality
 Weight
 Heavier seeds tend to grow faster and produce
larger plants
 Primed or enhanced
 Soaking in salt solutions of KCl or ethyl alcohol
 Causes growth hormones to become active

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More uniform, germinate sooner
GERMINATION MEDIUM

Soil characteristics
 Firm
 Porous
 Uniform in texture
 Sterile
 Free of weeds, insects, and disease organisms
SOIL COMPOSITION
 Loam
composed of:
45 % mineral matter
 5 % organic matter
 25 % air
 25 % water
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
What is loam?

Equal parts of sand, silt, and clay
GERMINATION MEDIA:
Peat moss
 Partially decomposed vegetation that has been
preserved under water
 Collected from marshes, bogs or swamps
 Has high capacity for holding water
 Sphagnum moss
 Dehydrated remains of acid bog plants
 Sterile and lightweight, controls disease and
has excellent water-holding capacity
 Perlite
 Volcanic origin that expands when heated
 Improves aeration and drainage of media
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GERMINATION MEDIA:
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Vermiculite
 Neutral pH
 High water-holding capacity
Jiffy mix
 Composed of sphagnum moss, peat, fine grade
vermiculite, and nutrients
To make your own media:
 Good grade, sterilized topsoil
 Proper drainage from sand or perlite
 Peat, moss or vermiculite to add water-holding
capacity
 1/3 soil, 1/3 drainage material, 1/3 water-holding
material
 Sterilized or pasteurized by heating at 180°F for
one-half hour