Module 4: Propagation by Cutting

Question 1

What is a cutting?

Answer 1

Piece of vegetative tissue that when placed under the correct environmental conditions will regenerate missing parts (roots/shoots/both) and develop into a self sustaining plant

Question 2

How do plants vary in their ability to form adventitious roots from cuttings?

Answer 2

Some produce roots using simplest procedures

Some produce roots if the factors that affect rooting are carefully observed

Some rarely or do not produce roots

Question 3

What are the different cuttings?

Answer 3

Stem cuttings
Leaf cuttings
Leaf-bud cuttings
Root cuttings

Question 4

What are stem cuttings?

Answer 4

Have terminal and or axillary buds

New roots must grow from the BASE of the cutting

Question 5

What are common herbaceous stem cuttings?

Answer 5

Many houseplants, geranium, chrysanthemums and can be easily rooted throughout the year

Question 6

What are softwood stem cuttings?

Answer 6

Taken from young leafy shoots of deciduous trees and shrubs grown in the spring.

Usually prepared in spring and are 10-15 cm long cuttings with the lower leaves removed

Question 7

What are common softwood stem cuttings?

Answer 7

Rose, plums, crepe myrtle

Question 8

What are semi-hardwood stem cuttings?

Answer 8

Similar cutting procedure as with softwoods

Best taken in midsummer after spring growth

Question 9

What are some common semi-hardwood stem cuttings?

Answer 9

Most broad leaved evergreen ornamental species and some fruit species

Rhododendron, holly, citrus, etc.

Question 10

What are deciduous hardwood stem cuttings

Answer 10

Taken in late winter/early spring from shoots grown from the previous summer with no leaves

Typically are 15-30 cm long cutting propagated outdoors with only the top bud showing

Question 11

What are common deciduous hardwood stem cuttings?

Answer 11

Willow, forsythia, grape

Question 12

What are narrow-leaved evergreen hardwood stem cuttings?

Answer 12

Usually taken in early winter

7-15cm cuttings, removing the needles in the lower half

Planted into flats or into greenhouse benches containing rooting medium

Question 13

What are some common narrow-leaves evergreen hardwood stem cuttings?

Answer 13

Many conifers

Question 14

What are leaf cuttings?

Answer 14

Have no buds, or roots, so both shoots and roots must form

Roots and usually usually grow from the base of the petiole with the leaf blade nourishing the new plants

Question 15

What is a leaf bud cutting?

Answer 15

Have a bud at the petiole base so only new roots are needed

Question 16

What are root cuttings?

Answer 16

Must produce new adventitious roots

2.5 cm long

Best harvested in late winter/early spring for the highest quantity of stored food

Question 17

What are some factors that affect the rooting of cuttings

Answer 17

Source of cutting material
Time of year
Etiolation
Treatment of cuttings with auxins
Misting
Bottom heat in cutting beds

Question 18

What is the plant breeders’ right?

Answer 18

Owner has the sole rights to produce and/or sell the propagating material of their cultivar

Can take legal action against those who propagate and sell material w/o permission

Rights are granted for 18-25 yr period (provided annual fee is paid)

Question 19

How does the source of cutting material affect the rooting of cuttings?

Answer 19

More success if source plant is growing in full sun at a moderate rate to accumulate as many carbs as possible

Rooting will be more successful with young non-flowering plants

Question 20

Why does time of year of the cutting being taken affect the rooting of the cutting?

Answer 20

Important for woody species

Question 21

How does etiolation affect the rooting of cuttings?

Answer 21

Growth of shoots with little or no light.

Stem tissue is more likely to develop roots if it is grown in darkness

Question 22

How does treatment of cuttings with auxins affect rooting?

Answer 22

Stimulates root growth

Question 23

How does misting affect rooting?

Answer 23

Reduces dehydration by increasing relative humidity and thus cooling the plant

Question 24

How does bottom heating in cutting beds affect rooting of cuttings?

Answer 24

Keep base of cuttings warmer (at 24C) and top of cuttings cooler (at 18.5C)