Bellringer 4.28.14• What is plant

propagation?

• What is a plant that is propagated asexually?

• Why would a grower want to asexually propagate?

Plant Propagation

Remember when you did this?

Now people do this.

What is plant propogation?Plant propagation is the process of artificially

or naturally propagating (distributing or spreading) plants

2 Types of Plant Propagation

• Sexual propagation—involves the exchange of genetic material between parents to produce a new generation.

• Asexual propagation—does not involve exchange of genetic material, so it almost always produces plants that are identical to a single parent.

What are the reasons for propagating plants asexually?

• Asexual propagation in plants involves the reproduction of new plants using only the vegetative parts of the parent plant.

• This is made possible by the plant’s ability to regenerate missing plant parts.

Sexual Propagation

Flower parts

Seeds are Formed by…Pollination:The transfer of pollen from the anthers to the female stigma by a pollinating agent such as wind, insects, birds, bats, or in a few cases the opening of the flower itself.

Fertilization: The fusion of two gametes (sperm and ovum) to produce a zygote that develops into a new individual with a genetic heritage derived from both parents.

Pollinators

Seeds- A packaged plant surrounded by endosperm (food) and protective seed coat

Germination of a Bean Seed

Asexual or Vegetative Propagation

• Leaf Cuttings and Leaf-bud Cuttings• Stem Cuttings• Root Cuttings• Division• Layering

– Tip Layering– Air Layering

• Grafting• Bulbs, Corms, Rhizomes, Tubers, Stolons

Cuttings

• Cuttings involve removing a piece from the parent plant and that piece then re-grows the lost parts or tissues.

• New plants can be grown from parts of plants because each living plant cell contains the ability to duplicate all plant parts and functions.

• Some plants will reproduce readily from cuttings and others take a considerable amount of time and care.

Leaf Cuttings- Use only the leaf

Vein cutting

from leaf

RememberPolarity or

which way is up!

Leaf Section Cutting

African violet

How do leaf cuttings grow?• Origins of roots and

shoots varies

• Meristem tissue - Group of embryonic cells that can differentiate and produce new cells

• Compounds trigger growth of roots and shoots

Root apical meristematic tissue of onion

Shoot apical meristematic tissue

Stem Cuttings- Use the stem and leaves or just the stem.

Cuttings should be 6-10” long & between nodes

Dibble, then placecutting in soil

How Do Stem Cuttings Work? • How roots develop

– Response to wounding-induced differentiation– Cells begin to divide – Callus begins to form– Certain cells begin to divide and initiate root

development

Stem Cuttings (cont’d.)

Preparing the cutting Planting the cutting

Root, Cane Cuttings- Uses roots or shoots

Stokesia Root

Blackberry root

Cane cutting

Bulbs- Specialized roots and stems

• Bulbs- Underground organ with scales and basal plate1. Tunicate- onion, garlic, daffodil, tulip2. Non-Tunicate- Lily

Corms- Specialized roots and stems

• Corms- Swollen base of stem axis, give rise to new bulblets

• Examples– Gladiolus, – Crocus

Gladioluscorm with bulblets

Bulbs and Corms• Bulbs can be propagated by

removing small bulblets or offsets that form at the base of the parent bulb.

Bulb (Tulips)

Corm (Crocus)

Rhizomes, Tubers, Stolons

Potato TuberStolon

Dahlia tuber

Iris rhizome

Tubers and Rhizomes

• Tuberous plants can be dug up and the tubers separated.

• In separating the tubers, each must have a segment of the crown that contains at least one eye or bud.

• Rhizomes grow and develop buds along their length.

• The rhizomes can be dug and cut into sections that each contain at least one eye or bud.

Tubers

Rhizomes

Division- To separate a clump into individual plants-Used for perennials and some houseplants

Photos from Garden Gate Magazine

Dig up Mother Plant Clean off root ball Separate roots to find individual plants and

plant

Divisions• Division is the cutting or breaking

up of a crown or clump of suckers into segments.

• Each segment must have a bud and some roots.

• These segments are replanted and grow into new plants identical to the parent.

• Carefully dig the plant, loosening the roots and lifting the plant from the soil.

Layering- Growing new plants while attached to the mother plant. They are later separated.

Ground layering

Air layering

Layering• Layering causes roots to

develop on shoots that are still attached to the parent plant.

• The stem is not cut from the main plant until it has rooted.

• Simple layering is done by bending a branch to the ground and burying a portion of it while the tip remains uncovered.

Grafting and Budding- Used to attach one plant to the other for strength or variety

Bud-graftingWhip Grafting

Grafting• Grafting involves the joining of

different segments of two different plants of the same species.

• Grafting allows gardeners to produce plants identical to a parent plant.

• It also allows growers to control size and shape of a tree or shrub.

• On the negative side, some grafting attempts will be rejected.

Budding or Bud Grafting• Bud grafting is faster, easier and

less messy than other forms of grafting.

• This method uses a newly developed latent bud, taken from under a live leaf.

• Budwood is collected from healthy branches that grew since spring and from young trees because they produce a large amounts of new growth.

• Use buds from the middle section of the branch.

How can I propagate my bulbs?

• Tunicate Bulbs– Cuttage (8 Sections)

• Non-tunicate Bulbs

Bulb Scales

When to propagate• Late spring and early summer= optimal

growing time• Depends on type of cutting • Need to check resources for specific plants.

Each one may have an optimal time• Some seeds need to go through stratification

or period of cold to break dormancy• Some seeds need to be scarified or scratched

Propagation Environment• Aerial Environment

– Humidity– Light– Temperature– Air quality

• Growing Medium– Moisture level– Temperature– Aeration– pH– Nutrient level

Equipment and Hygiene- Keep everything clean so disease is not spread

Pruning knife

Hand cutters

Watering CanLiners

and Light

Sterilize all toolswith alcohol after

use!

Soil• Purpose of soil

– Larger particles (sand) holds plant in place – Smaller particles hold water and nutrients

• Ingredients in soil– Vermiculite= Holds moisture– Perlite= Increases aeration– Peat=Moisten –Helps stop decomposition – Sand=Drainage– Sphagnum Moss= Holds water well, lightweight

• Recipes and proportions vary depending on plant!

When can I plant it?

• Gently tug on the cutting to see if your plant has developed a good root system

• Repot in larger pot if necessary

Have fun and enjoy your new plants!

EXIT SLIP

1. What are two advantages of asexual propagation?

2. Name a plant that can be propagated from a leaf cutting

3. What is a meristem?4. Why are meristems important for

propagation?