Chapter 27: Vegetative Propagation

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Chapter 27: Vegetative Propagation

  • Vegetative propagation is a type of asexual reproduction in plants.
  • Asexual reproduction is the production of a new individual from one parent.

There are two main types of vegetative propagation:

1. Natural vegetative propagation
2. Artificial vegetative propagation

1. Natural Vegetative Propagation
There are four sub-types of natural vegetative propagation. These occur free in nature.

(i) Stem propagation: brand new plants can arise from stems of certain species of plants, e.g. the strawberry plant. The strawberry plant sends out long branches from its stem that run along the surface of the soil – they are called “runners”. When they are far enough away from the parent plant they send out a shoot and a root and a new strawberry plant is produced.

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(ii) Root propagation: brand new plants can arise from the roots of certain plants, e.g. the raspberry plant. The raspberry plant sends out shoots from the roots under the ground. These are called root sprouts or “suckers”. They eventually develop into a new plant.
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(iii) Leaf propagation: this type of propagation is extremely rare. It occurs in the Devil’s backbone plant (native to Madagascar). Tiny leaflets develop along the edge of a main leaf and then fall off and develop into a new plant.
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(iv) Bud propagation: buds are new growth points found on all plants. Some buds of some species of plant are capable of producing a new plant, e.g. onion plant.
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2. Artificial vegetative propagation
There are four sub-types of artificial vegetative propagation. These are used by farmers and horticulturists to propagate plants rapidly.

(i) Cutting propagation: removal of a small piece of a parent plant and growing it with the use of various growth regulators, e.g. rooting powders such as IBA or NAA.

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(ii) Layering propagation: stem is bent down into the soil nearby and growth regulators added; used on climbing plants such as clematis.
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(iii) Grafting propagation: shoot system (scion) of one plant is attached to the root system (stock) of another plant; used for producing large brightly coloured roses or eating apples, both of whose own natural stocks are weak. A strong grafted stock helps to produce a better crop.
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(iv) Tissue culture propagation (micropropagation): growing a large number of plantlets in nutrient medium from small tissue samples. It is very expensive and labour intensive.
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