Growing plants artificially

or

Artificial propagation

In this work we will be looking at the some ofthe different methods that humans use to increase the number of plants artificially

At the end of the work you should• have had practical experience in growing

plants artificially• have knowledge of a number of methods

to grow plants artificially• be able to explain how and why plants are

grown artificially

Artificial propagationArtificial propagation is used to increasethe number of plants using ways that plants cannot naturally use

Artificial propagation makes use of the facts that plants have growing points and under the right conditions these points can be wounded and this will encourage theplant to grow either new roots or leaves

The growing points in plants

Naturally plants grow at specific points.These are root and shoots tips

But they also include buds, nodes and stems

These can be used to grow plants artificially

The growing points in plants

side branch

stem

node

leaf stalk

bud

shoot tip

root tip

Cuttings

Leaf cuttings can be taken from plantslike Begonia or African violet

Stem cuttings can be taken from plantslike geranium or wandering sailor

Cuttings can be used to artificially propagateplants.These include stem and leaf cuttings.

Taking stem cuttings

• The stem is cut just below a node.• The lower leaves are removed to

prevent water loss• The cutting is placed in water or compost

to produce roots

Your teacher will now demonstrate this

Leaf cutting

The leaf is removed from the plant and placed on compost.The leaf will begin to grow roots and eventually becomes a new plantidentical to the parent.

Plants produced naturally by asexualreproduction or artificially by leaf or stemcuttings will be clones of their parents.

What does this mean?How might being a clone effect the offspring?

Care of plants

When growing plants what are some important factors to control?

How might these factors be controlledwhen growing plants using artificial propagation techniques ?

Controlling temperature• Heaters controlled by thermostats are

used to provide warmth• Warmth encourages root and

shoot growth• Care must be taken not to dry the

plants out too much• Warmth can also encourage diseases

like fungi, when combined with moisture

Reducing water lossIn artificial propagation it is important tocontrol water loss from the new plant This can be done by:• Removing lower leaves on cuttings• Covering the new plants with a plastic bag• Putting the new plants in a propagator• Using misting sprays

Quiz1. What is a node?2. Where should a cutting be taken?3. Why are the lower leaves removed?4. Why are the upper leaves and buds left?5. Why keep cuttings in the shade not full sun?6. Why keep cuttings suitably moist and warm?7. What is a disadvantage of too much

warmth and moisture?8. Name some plants that can be artificially

propagated using cuttings.