Artificial vegetative propagation

Question 1

Apart from the natural methods of vegetative reproduction, a number of artificial methods are employed to reproduce plants by vegetative methods. Name some fields in which these methods are used in and why they are used. (2)

Answer 1

Apart from the natural methods of vegetative reproduction, a number of artificial methods are employed to reproduce plants by vegetative methods.

These methods are widely used in horticulture (growing plants) and agriculture to propagate (reproduce) new plants that are identical to the parent..

Question 2

Define a cutting

Answer 2

A cutting is a portion of a plant that is removed from the parent plant and grown into a new independent plant.

Question 3

What are cuttings of a plant?

Answer 3

Cuttings are parts of a plant (usually shoots) that are removed from the parent plant and allowed to form new roots and leaves.

Question 4

How must the shoot be cut when taking a cutting and what is done with it?

Answer 4

The shoot is cut at an angle and is often treated with rooting powder (a growth promoter) to speed up root formation.

Question 5

Why is propagation a good method of artificial vegetative propagation?

Answer 5

Propagation by cuttings is a simple, cheap method of producing large numbers of similar plants.

Question 6

Give examples of plants that cuttings can be taken from

Answer 6

Examples of the many plants that can be propagated by cuttings are busy Lizzie, geranium and willow.

Question 7

Define grafting

Answer 7

Grafting is the joining and uniting of part of one plant with a second plant

Question 8

Why is grafting used?

Answer 8

Grafting is used to combine useful qualities or traits from two different plants into one plant.

Question 9

What is done during grafting (process)?

Answer 9

When grafting plants, part of one plant is removed and attached to a healthy, rooted part of a second plant.

Question 10

To be successful, what must be done during grafting?

Answer 10

To be successful the graft has to achieve good contact between the growth areas (meristems) and vascular tissue of both plants.

Question 11

What does the graft have to make contact with in order to be successful?

Answer 11

good contact between the growth areas (meristems) and vascular tissue of both plants

Question 12

What are the growth areas of plants also known as?

Answer 12

meristems

Question 13

Give an example of a situation where grafting is used with rose plants

Answer 13

In roses, a plant with large flowers (but a poor root system) can be grafted to a wild rose with large roots (but with small, insignificant flowers). In this way the best features of both plants can be combined (see diagram 40.10)

Question 14

Give an example of a situation where grafting is used with apple trees

Answer 14

Eating-apple trees can be grafted to crab-apple plants. This produces well-rooted plants that produce good-quality eating apples.

Question 15

Define layering

Answer 15

Layering is the growth of a new plant from a stem that is still attached to the parent plant.

Question 16

Explain the method of layering a plant/what happens?

Answer 16

In layering, a branch of a parent plant is bent down and covered in soil, except at the tip. The covered part forms roots and the exposed tip forms new shoots. In time the two plants may be separated.

Question 17

Give examples of plants that may be propagated by layering (3)

Answer 17

Examples of plants that may be propagated by layering are blackberries, climbing roses and spider plants.

Question 18

Do many plants or a few plants propagate naturally by layering? Give an example

Answer 18

Many plants propagate naturally by layering, e.g. strawberries.

Question 19

Define micropropagation

Answer 19

Micropropagation is the growth of plants from small pieces of tissue under sterile conditions on a specially selected medium.

Question 20

What is micropropagation also known as?

Answer 20

Micropropagation is also called tissue culturing

Question 21

What does micropropagation involve doing?

Answer 21

It involves growing large numbers of plants from small pieces (often single cells) of a parent plant.

Question 22

Is micropropagation an easy or hard process, etc?

Answer 22

It is an expensive and very specialised process.

Question 23

What is micropropagation often used to produce?

Answer 23

It is often used to produce large numbers of newly developed plants or plants that do not reproduce from seeds.

Question 24

What are the four methods of artificial vegetative propagation that you will study?

Answer 24

micropropagation, layering, cutting, grafting

Question 25

What are the 3 advantages of artificial vegetative propagation?

Answer 25

It is a simple and reliable process

New plants form fast

New plants are the same as the parents.

Question 26

What are the 3 disadvantages of artificial vegetative propagation?

Answer 26

There is a lack of variation

Diseases can be passed from the parent to the offspring plant

If it is carried out repeatedly the plants may lack vigour.