Vegetative Propagation Saturday, 23 June 2018 Learning question: What are the different ways that plants reproduce asexually?

Learning objectives Describe methods of vegetative reproduction including runners, tubers, bulbs, underground stems, root suckers and tap roots

Key words: Vegetative propagation Tubers Runners Bulbs Asexual reproduction

https://www.youtube.com/watch?v=3O7icCqFfEo

Vegetative Propagation “Vegetative propagation” means the ways that plants can make copies of themselves without making seeds Gardeners use vegetative propagation to increase the numbers of a plant Propagated plants have identical characteristics to the “parent” plant – they are genetic copies

Types of vegetative propagation Vegetative propagation can be natural - the plant will make copies of itself using structures like bulbs. Or vegetative propagation might be artificial - gardeners can make new plants in a way that the plant is unable to do naturally - for example, taking cuttings. Daffodil bulbs

Natural vegetative propagation - bulbs Bulbs are leaf bases, swollen with food and are called food storage organs The leaves may die back each winter, but the bulbs will grow into new plants the following spring The bulbs may make daughter bulbs - so each year, more plants may grow. Daffodil bulbs. The plant on the right has grown a daughter bulb.

Natural vegetative propagation - tubers Tubers are underground stems or roots that are swollen with food, so are also food storage organs Each tuber can grow into another plant the next year, using food stored in the tuber to start it off New potato plant growing from one of last year’s tubers. New tubers will form on underground stems.

Leaf edge plantlets This Mexican hat plant has produced plantlets at the edge of its leaves. They will drop off, grow roots and grow into new plants.

Quick Questions Name two food storage organs that are natural plant propagation structures What kind of food storage organ does a potato plant produce? What kind of food storage organ is an onion? What method of propagation is used by the Mexican hat plant?

Answers Bulbs and tubers Tuber Bulb Leaf edge plantlet

Attached Offspring

Introduction There are many different forms in which plants can copy themselves by natural vegetative propagation Examples we have looked at are: Mexican hat plants potatoes Daffodil bulbs onions

Other Examples Some plants produce tiny little plants called plantlets which are joined on to the parent as they develop and grow e.g. Mother of thousands Spider plant

Runners and Offsets Other natural plant propagation structures are runners and offsets A runner is a horizontal stem with plantlets at intervals along its stem. A good example of a runner is the spider plant Offsets are small plantlets produced as a side shoot at the base of the parent plant

Runners Spider plants and mother of thousand produce runners These are long horizontal stems with little plants at the end They can be pegged down in a pot and left attached to the parent until the roots grow After roots grow, the long stem can be cut and a new independent plant can be produced

Mexican hat plant with plantlets at the leaf edges Spider plant with plantlets on the end of runners

Growing Plants from Offsets An offset is a tiny plantlet that develops as a side shoot at the base of the parent plant. They are often found in cactus type plants. Sometimes several different offsets are produced and form a clump at the base of the parent plant

Offsets

Label the type of plantlet being removed from the parent plant

Review task Make a summary mind map of the different types of vegetative propagation structures. You can do this using online mind map software, or you can do this on paper (https://app.mindmup.com/map/new/150086119543) Your summary should include: Definition of vegetative propagation Examples of how different plants do this Clear diagrams to show how these different types of propagation work