R2104 4.1 Describe how juvenility and plant health affect success of vegetative propagation

Question 1

What is meant by ‘Juvenility’?

Answer 1

It is the young or immature stage in a plants life. The plant does not flower in the juvenile stage, but remains in the vegetative state.

Juvenile growth is more vigorous. Once plant reaches the mature stage it become woody which can prevent rooting. Plant hormone levels alter as a plant matures, and the juvenile material is more likely to have more appropriate levels of the plant hormone auxin.

Question 2

What is needed for the correct health of rooting? General - 3

Answer 2

1. Freedom from pests and diseases. Viruses can be easily transmitted
2. Correct nutritional status - no nutrient deficiencies. A balance between carbon and nitrogen is needed. A low nitrogen to carbon balance is best
3. Correct light conditions - in general good light levels. Helps build up high energy reserves for subsequent root and shoot production

Question 3

Auxin

Answer 3

1. Plant homone needed for the material to root
2. For some cutting artifical auxin can be used in the form of hormone rooting powder. It must be applied where needed - it cannot translocate through the plant like a natural hormone. Some powders may contain a fungicide.

Question 4

Effect of juvenility

Answer 4

1. Material is easiest to root. Once a plant enters fruiting or flower stage it roots less readily
2. There is more cell division in juvenile growth
3. Cutting back a shrub hard forces new growth which is suitable for propagation