ASEXUAL REPRODUCTION IN PLANTS

Asexual Reproduction

• Making genetic duplicates of a plant

• Cloning

Advantages

• Maintains Genetic Purity

• Some Plants Are Difficult To Grow By Seed

• Quicker Than Seed

Disadvantages

• Can be expensive

• No genetic diversity

Asexual Processes

Layering

Cutting

Budding

Grafting

Separation and Division

Tissue Culture

Layering

• Involves getting roots to grow from the stem

Layering

• Can be natural or human-assisted

Simple/Tip Layering

• Stem bends to the ground and roots sprout

• Example: Forsythia, Grapes

Air Layering• The outer layer of stem is removed, moist

media applied, and sealed.

• Example: Ficus, Rubber Plant

Cuttings

• Uses a short section of plant stem, root, or leaf for propagation.

• Most common form of asexual propagation

• Must be taken at the right time

• Cutting material can be put into soil or water depending on the type

Stem Cuttings

• Uses part of a stem with bud(s)

Leaf Cuttings

• Uses a leaf blade or petiole and blade

Leaf-Bud Cuttings

• Uses a small bit of stem and a leaf

Root Cuttings

• Uses pieces of root from young plants in late winter/early spring

Grafting

• Uniting a section of one plant onto another plant

• Done to use the best parts of different varieties

Grafting

• Uniting a section of one plant onto another plant

• Done to use the best parts of different varieties

Grafting

• Uniting a section of one plant onto another plant

• Done to use the best parts of different varieties

Grafting

• Uniting a section of one plant onto another plant

• Done to use the best parts of different varieties

Grafting

• Uniting a section of one plant onto another plant

• Done to use the best parts of different varieties

Grafting

• Uniting a section of one plant onto another plant

• Done to use the best parts of different varieties

Grafting

• Uniting a section of one plant onto another plant

• Done to use the best parts of different varieties

Grafting

• Uniting a section of one plant onto another plant

• Done to use the best parts of different varieties

Key Grafting Parts

• Scion - a piece of stem with 2+ buds

• Rootstock (Understock) - the under part of the graft

Grafting

• Important in the rose and fruit industries

Grafting

Types of Grafting

• Whip and Tongue Graft

• Cleft Graft

• Bark Graft

Whip and Tongue Graft

Cleft Graft

Cleft Graft

Bark Graft

Budding

• Taking a bud from one plant and moving it to another

• Done in early spring

Types of Budding

• T-Budding

• Patch Budding

T-Budding

Patch Budding

Separation and Division

• Some plants have structures that can be separated from the parent plant and will grow into a new plant.

Separation and Division

• Separation is the natural process when these structures separate on their own.

• Most bulbs and corms do this.

Separation and Division

• Division is when people split plants.

• This can be done with tubers, rhizomes, and plants with strong crowns Crocus

Tissue Culture

• Taking a group of cells or a single cell and growing it to a plant

• Also called Micro-Propagation

Tissue Culture

• Requires near sterile lab conditions.

• Grows new plant from a cell or a few cells

• Grows in agar – a sugar/algae based gel

Tissue Culture• Important tool for

saving endangered plants

• Used commercially to produce pathogen-free plants

RecapAsexual Propagation

• Helps with ‘difficult’ plants• Produces mature plants

quicker

Types• Layering• Cutting• Budding• Grafting• Separation and Division• Tissue Culture

Key Terms• Scion• Rootstock• Agar• Micro-Propagation