Plant Cloning: Vegetative Propagation
This lesson covers:
- What vegetative propagation is
- Methods of natural vegetative propagation
- How to artificially propagate plants from cuttings
- Advantages and disadvantages of vegetative propagation
What is vegetative propagation?
Vegetative propagation is a form of asexual reproduction where new, genetically identical individuals develop from non-reproductive tissues of a parent plant such as its roots, stems, and leaves.
Asexual reproduction is the production of offspring that are genetically identical to the parent. This process doesn't involve the fusion of gametes, and the offspring produced are known as 'clones'.
Methods of natural vegetative propagation
Plants use several natural methods for vegetative propagation to reproduce asexually.
| Method | Description | Example plants |
|---|---|---|
| Rhizomes | Specialised horizontal underground stems that store food and can produce new vertical shoots and roots from buds on nodes along the rhizome. | Marram grass |
| Stolons (runners) | Horizontal stems that grow along the soil surface away from the parent plant, with nodes or stem tips that can root to form a new plant upon contact with the ground. | Strawberries |
| Suckers | Shoots that emerge from the shallow root buds of the parent plant. | Elm trees |
| Tubers | Form when the tip of a stem becomes swollen with food, with buds on the tuber surface that can develop into new shoots. | Potatoes |
| Bulbs | Form when a leaf base becomes swollen with stored food, and the bud inside the bulb can form new shoots. | Daffodil |
Perennating organs, such as tubers and bulbs, are organs in plants that store food to help the plant survive from one season to the next while it is dormant.
How to artificially propagate plants from cuttings
A cutting is a section of a stem, root, or leaf taken from the parent plant and planted in soil, which then grows into a clone of the parent. Taking and growing cuttings is a method used to clone plants artificially.
For stem cuttings:
- Cut a 5-10 cm piece from the end of a parent plant's stem using a sharp, sterile tool.
- Remove the lower leaves, leaving only one leaf at the top.
- Dip the cut end in rooting powder, which contains plant hormones that encourage root growth.
- Plant the cutting in a suitable growth medium, such as compost.
- Place it in warm, moist conditions to promote root development.
- Once rooted, transplant the new clone.
For root or leaf cuttings:
- Root cuttings - Take a section of root and make an angled cut on one end before treating it as you would a stem cutting.
- Leaf cuttings - Remove an entire leaf, score the veins, and place it in a growing medium with the scored veins facing down.
Advantages and disadvantages of vegetative propagation
There are several advantages and disadvantages of vegetative propagation.
Advantages of vegetative propagation:
- It is fast.
- It ensures a high yield.
- It is cost effective.
- It maintains the quality of the crop because the new plants have the same genetic traits as their parents.
- It allows plants to survive adverse conditions and regenerate each season.
Disadvantages of vegetative propagation:
- It results in a lack of genetic variation in offspring.
- The plants are more susceptible to diseases, pests, and climate change.