Vegetative Propagation and Micropropagation | ICSE Class 9 Biology Notes

This note covers the ICSE Class 8 Biology topic Vegetative Propagation and Micropropagation: how asexual and sexual reproduction differ, the main types of asexual reproduction (binary fission, budding, fragmentation and spore formation), natural vegetative propagation from stems, roots and leaves, the artificial methods of cutting, layering, grafting and budding, the advantages and disadvantages of vegetative propagation, tissue culture or micropropagation and its basic steps, the economic importance of artificial propagation, and simple activities with a money plant, a potato and a Bryophyllum leaf.

What is reproduction, and how do asexual and sexual reproduction differ?

Reproduction is the biological process by which living beings produce new individuals of their own kind. It is essential for the continuation of a species. A mango tree may grow old and die, but its seeds grow into new mango plants.

Living organisms give rise to new organisms in two ways: asexual reproduction and sexual reproduction. The key difference is the number of parents involved.

One parent or two

Asexual reproduction involves a single parent. The offspring it produces are almost exact copies of that parent. In plants, asexual reproduction gives new plants without the production of seeds.

Sexual reproduction involves two different individuals of different sexes, one male and one female. A male gamete fuses with a female gamete to form a zygote; in animals these gametes are the sperm and the egg. In flowering plants, seeds are produced as a result of sexual reproduction.

Bulls alone cannot produce new calves, and hens alone cannot produce new chicks: both sexes are needed. The offspring of sexual reproduction inherit a mix of characteristics from the two parents, so they show small differences from each parent.

Why the difference matters

A basic event in reproduction is making a copy of the cell's DNA, the information for inheritance. In asexual reproduction, cells divide by mitosis, and the offspring are genetically identical to the parent. Such offspring are called clones.

In sexual reproduction, a special division called meiosis forms the gametes, and the mixing of characters from two parents creates variation. Accumulated over many generations, such differences help living beings adapt to changing environments.

What are the main types of asexual reproduction?

Asexual reproduction is seen in many unicellular organisms, such as bacteria, Amoeba and yeast, in simple multicellular organisms such as Hydra and sponges, and in many plants. All of these modes allow a new generation to be created from a single individual.

Binary fission

In unicellular organisms, cell division, or fission, creates new individuals. Many bacteria and protozoa simply split into two equal halves. In Amoeba the split can take place in any plane, while in Leishmania, which has a whip-like structure at one end, it occurs in a definite orientation.

A row of drawings joined by arrows: a single Amoeba with one nucleus, then the nucleus stretching and dividing into two, then the cell pinching in at the middle with one nucleus on each side, and finally two separate daughter Amoebae moving apart.

See Fig. 7.1(a) in your NCERT textbook

Budding

In yeast, a small bulb-like projection called a bud comes out of the cell. It grows, detaches and forms a new yeast cell; sometimes another bud arises from the bud, forming a chain. In Hydra, repeated cell division at one specific site produces a bud that grows into a tiny individual and detaches when fully mature.

Fragmentation and spore formation

In fragmentation, a filament of the alga Spirogyra breaks up into smaller pieces on maturing, and each fragment grows into a new individual. In this way algae cover a large area in a short time.

In spore formation, the bread mould Rhizopus bears tiny round sacs called sporangia on thin stalks. They contain spores, which are light, float in the air and have a hard, thick protective covering. When a spore lands on a moist surface, it germinates into a new individual.

What is vegetative propagation?

Most plants have roots, stems and leaves. These are called the vegetative parts of a plant, as distinct from the flowers, which are the reproductive parts.

Definition: Vegetative propagation is a type of asexual reproduction in which new plants are produced from the roots, stems, leaves or buds of a plant, that is, from its vegetative or growing parts, without seeds.

In many plants, a root, stem or leaf develops into a new plant under appropriate conditions. Unlike most animals, plants can use this as a mode of reproduction. Because only one parent is involved, the plants produced are genetically identical to the parent.

The role of buds

Apart from flower buds, plants have buds in the axil of their leaves, the point where a leaf is attached to the stem at a node. These buds develop into shoots and are called vegetative buds.

A bud consists of a short stem around which immature, overlapping leaves are present. Vegetative buds can give rise to whole new plants, which is why a stem cutting needs to include a node.

Natural and artificial vegetative propagation

In natural vegetative propagation, a part of the plant forms a new plant on its own, as when a potato sprouts or a fallen Bryophyllum leaf produces plantlets. Grass plants planted at some distance from each other cover the entire soil after some days in this way.

Scientists and horticulturists have adapted this natural process into methods of artificial propagation: cutting, layering, grafting, budding and tissue culture. Gardeners and nurseries use these methods, and natural parts such as tubers and suckers, to multiply plants such as jasmine, rose, Chrysanthemum, Dahlia, potato and money plant.

How do plants reproduce naturally from their stems?

The stem is the part most often used in natural vegetative propagation, because it bears nodes and buds. Some stems store food, and some serve for vegetative propagation.

Potato

The potato is a fleshy underground stem (a stem tuber), not a root. Its surface shows small scars or notches called eyes, and each eye has one or more buds.

When a piece of potato with an eye is kept on wet cotton or buried in moist soil, the buds sprout into fresh green shoots and roots. Each piece with an eye can grow into a new potato plant, using food stored in the tuber.

A photograph of a heap of potatoes, several of which have short, pale green shoots growing out of small scars (eyes) scattered over their surface.

See Fig. 8.2 in your NCERT textbook

Ginger and turmeric

Ginger is also a fleshy underground stem that sprouts new plants without producing seeds. A piece of ginger sends up new leafy shoots and roots, and turmeric can be grown in the same way.

Grass

Many grasses spread by runners: thin stems that grow along the surface of the soil. At their nodes they put down roots and send up leaves, so a row of new plants forms along each runner. This is why grass covers bare ground quickly.

Chrysanthemum

A Chrysanthemum plant produces suckers: shoots that grow from the underground part of the stem near the base and come up through the soil with their own roots. Each sucker can be separated from the clump and planted as a new plant.

Jasmine

Jasmine has lost the capacity to produce seeds, so it is multiplied from its vegetative parts. When a low branch bends down and touches moist soil, it can form roots at the point of contact; gardeners copy this natural process in the method called layering.

How do roots and leaves give rise to new plants?

Stems are not the only vegetative parts that can form new plants. The roots of some plants and the leaves of a few plants also produce new plants.

Roots: Dahlia and sweet potato

The roots of some plants can give rise to new plants; the sweet potato and Dahlia are examples. A Dahlia plant forms a cluster of swollen, food-storing tuberous roots.

When such a clump of roots, with a piece of the old stem base attached, is planted, the buds at the stem base grow into new shoots, using the food stored in the roots.

Leaves: Bryophyllum

Bryophyllum, the sprout leaf plant, has buds in the notches along the margin of its leaves. If a leaf falls on moist soil, each bud can develop into a tiny plantlet and then into a new plant. One leaf can therefore produce several new plants.

A single, broad leaf lying flat, with small plantlets growing from the notches along its edge. The plantlets have a few tiny leaves, and those along the lower edge also show thread-like roots; the label "Buds" points to one of them.

See Fig. 7.5 in your NCERT textbook

Detached parts: cacti

Plants such as cacti produce new plants when their parts get detached from the main plant body. Each detached part can grow into a new plant.

How do gardeners raise new plants from cuttings?

A cutting is a piece of a branch, with at least one node, that is planted to grow a new plant. A branch of rose or champa with a node can be buried in soil and watered daily. After some days, roots come out and new leaves arise.

A money plant can be grown from a piece of its stem kept in a jar of water, and sugarcane is grown from stem cuttings. In nurseries, cuttings are used to grow large numbers of roses.

Steps in raising stem cuttings

1. Choose a healthy plant and cut shoots for planting, preferably in the morning; note the length of each cutting and count its nodes and internodes.
2. Remove the leaves from the lower half of each cutting.
3. Insert each cutting up to about half its length in soil mixed with compost, at an angle of about 45 to 60° to the soil surface.
4. Water the cuttings regularly.
5. Observe them over the following days: roots form from the buried part, and new leaves grow from the buds above the soil.

A short piece of rose stem with a few leaves at its upper end. A node is labelled on the stem, and an enlarged view beside it shows the "Bud in the axil", where the leaf stalk joins the stem.

See Fig. 8.1 in your NCERT textbook

Why a node is needed

The node carries a vegetative bud, which can grow into a new shoot. A piece of stem cut from between two nodes has no bud, so it usually fails to grow into a new plant. This can be tested with money plant cuttings, as described in the activities section.

How are layering and grafting done?

Layering and grafting use the natural ability of plants to propagate vegetatively. Along with cuttings, such methods are used to grow many plants for agricultural purposes, such as sugarcane, roses and grapes.

Layering

In layering, a branch is made to form roots while it is still attached to the parent plant, and is separated only after the roots have formed. Lemon and jasmine can be propagated in this way.

1. Select a flexible, thin twig of a tree or shrub, such as a lemon, and bury its middle part under the soil surface.
2. Water it regularly, and observe the growth of new leaves on the twig.
3. After 10 to 15 days, roots develop from the part of the twig buried in the soil.
4. Once the roots have developed, cut the twig from the parent plant, so that it grows as a separate new plant.

A small fruit tree with green and yellow fruits. One long, low branch bends down and is buried in the soil some distance from the trunk; roots have grown from the buried part, and the leafy end of the branch stands up above the soil.

See Fig. 11.4 in your NCERT textbook

Grafting

In grafting, a stem piece of one plant is joined to a rooted plant of another variety so that the two grow as one plant. The rooted plant is called the stock, and the stem piece joined to it is called the scion.

1. Take a healthy rooted plant (Plant A), for example a wild rose variety, and a healthy stem piece from a plant of another variety (Plant B), for example a yellow rose or a pink rose.
2. Make a wound or slit on a twig of Plant A.
3. Insert and fit the cut stem of Plant B into the slit in the stem of Plant A.
4. Protect the joint with a cotton cloth or wrapping film, to keep pests out until it heals, and cut the other branches of Plant A.
5. Water the plant regularly and observe Plant B growing along with Plant A.

Seven small drawings, (a) to (g). (a) A rooted Plant A in soil; (b) a knife cutting a slit in the side of its stem; (c) a knife shaping a stem piece of Plant B, with the slit labelled; (d) the shaped stem piece; (e) the piece fitted into the stem of Plant A; (f) the joint wrapped and labelled "Graft", while a knife removes another branch of Plant A; (g) the grafted piece growing fresh leaves.

See Fig. 11.3 in your NCERT textbook

The stock supplies roots, water and minerals, and the scion grows into the shoot that bears the desired flowers or fruits.

What is budding in a rose nursery, and how do the artificial methods compare?

In a nursery, cuttings and budding are used to grow larger numbers of roses. Budding is a kind of grafting in which a single bud, instead of a whole stem piece, is joined to a rooted stock plant.

Steps in budding a rose

1. Choose a healthy, rooted rose plant of a hardy variety as the stock.
2. Make a T-shaped cut in the bark of its stem, near the base, and gently lift the flaps of bark.
3. Slice a single bud from a branch of the desired rose variety, with a thin shield of bark around it.
4. Slip the bud under the bark flaps so that it fits closely against the stock, and tie the joint firmly, leaving the bud itself uncovered.
5. When the bud has joined and begins to grow, cut off the stock's own shoot above it, so that the new shoot grows into a plant of the desired variety.

Note: Budding as a nursery method is not the same as budding in yeast or Hydra. In yeast and Hydra, a bud is an outgrowth that grows into a new organism by itself; in a nursery, a bud of one plant is joined to another rooted plant.

Comparing the artificial methods

What are the advantages and disadvantages of vegetative propagation?

Vegetative propagation is practised for growing some types of plants because it has clear advantages. It also has some disadvantages, which come mostly from the fact that the new plants are copies of one parent.

Advantages

• Earlier flowering and fruiting: plants raised by vegetative propagation take less time to grow and bear flowers and fruits earlier than those produced from seeds.
• Seedless plants can be grown: plants such as banana, orange, rose and jasmine have lost the capacity to produce seeds, and can still be propagated from their vegetative parts.
• Parent's characteristics are kept: all the plants produced are genetically similar enough to the parent plant to have all its characteristics, so a good variety stays the same.
• Large-scale cultivation: these methods let farmers grow desirable crops on a large scale.

Disadvantages

• No variation: the new plants are copies of the parent, so there is no variation. If the conditions change, for example through a rise in temperature or a new disease, all the plants may be affected alike.
• Disease passes to the offspring: if the parent plant is infected, for example by a virus, the infection is usually carried into the new plants grown from its parts.
• Crowding: new plants formed naturally, as in potato or grass, often grow close to the parent and to each other, so they compete for space, light, water and minerals.

What is tissue culture, and how is micropropagation carried out?

Definition: Tissue culture is a method of artificial propagation in which new plants are grown from tissue or cells removed from the growing tip of a plant, on an artificial nutrient medium under sterile conditions.

During the 1950s, scientists learnt that whole plants could be regenerated from explants, that is, any part of a plant taken out and grown in a test tube under sterile conditions in special nutrient media. The capacity of a cell or explant to generate a whole plant is called totipotency.

The nutrient medium

The nutrient medium must provide a carbon source such as sucrose, as well as inorganic salts, vitamins, amino acids and growth regulators such as auxins and cytokinins. It is kept sterile so that no microbes grow on it.

Basic steps of tissue culture

1. Tissue is removed, or cells are separated, from the growing tip of a plant.
2. The tissue is placed on a sterile artificial nutrient medium, where the cells divide rapidly to form a small group of cells called a callus.
3. The callus is transferred to another medium containing hormones for growth and differentiation.
4. The cells of the callus develop into small plants with shoots and roots, called plantlets.
5. The plantlets are placed in the soil, so that they can grow into mature plants.

On the left, a closed glass jar holding many small green plantlets growing on a layer of medium. A curved arrow leads from the jar to a photograph, on the right, of a field of tall banana plants in rows.

See Fig. 11.5 in your NCERT textbook

What micropropagation means

Definition: Micropropagation is the method of producing thousands of plants through tissue culture. The plants produced are genetically identical to the original plant and are called somaclones.

Using tissue culture, many plants can be grown from one parent in disease-free conditions, and a large number of plants can be produced in a very short time. The technique is commonly used for ornamental plants.

Draw a flow chart of five boxes joined by arrows: a shoot tip cut from a plant; a small piece of tissue on a nutrient medium in a test tube; a callus (a lump of cells) on the medium; plantlets with shoots and roots on a medium with hormones; a young plant in a pot of soil.

Why is artificial propagation economically important?

Artificial propagation has changed farming and gardening. It allows growers to produce many good-quality plants quickly and in large numbers.

Nursery and horticulture trade

Nurseries use cuttings and budding to grow large numbers of roses and other garden plants. Rooted cuttings, grafted plants and budded plants are sold to gardeners and farmers. Tissue culture is commonly used for ornamental plants, which are grown in large numbers for sale.

Uniform crops

Because the plants are genetically identical to the parent, a farmer who plants them gets a uniform crop with the same qualities as the chosen parent. These methods let farmers cultivate desirable crops on a large scale.

Many important food plants, such as tomato, banana and apple, have been produced on a commercial scale by micropropagation.

Virus-free planting stock

Even if a plant is infected with a virus, its meristem (apical and axillary) is free of virus. The meristem can be removed and grown in a test tube to obtain virus-free plants. Meristems of banana, sugarcane and potato have been cultured in this way.

Tissue culture has changed banana farming in particular. Farmers are given mass-produced healthy plantlets from the shoot tip (apical meristem), which helps eliminate virus-infected plants and gives high yields.

Other benefits

• Seedless crops: banana and orange, which have lost the capacity to produce seeds, are multiplied by vegetative methods.
• Training for farmers: Krishi Vigyan Kendras (KVKs) under the Indian Council of Agricultural Research (ICAR) help farmers learn modern grafting to grow high-yield fruits and boost their income.

Which simple activities show vegetative propagation?

Simple activities at home or in school show that vegetative parts can produce new plants. During a visit to a garden or nursery, students can also note the common names of plants and ask the gardener how plants such as jasmine, rose, Bryophyllum, Chrysanthemum, Dahlia, potato and money plant are multiplied.

Activity 1: Money plant cuttings in water

1. Select a money plant.
2. Cut some pieces of stem such that each contains at least one leaf.
3. Cut some other pieces from the portions between two leaves.
4. Dip one end of every piece in water and observe them over the next few days.
5. Record which pieces grow roots and give rise to fresh leaves.

Observation and conclusion: the pieces with a leaf include a node with a bud, and they grow roots and fresh leaves. The pieces cut from between two leaves have no node and do not grow. A new plant arises from a part of the stem that carries a node.

Activity 2: A Bryophyllum leaf on moist soil

1. Take a healthy, mature leaf of Bryophyllum.
2. Lay it flat on moist soil in a pot or tray.
3. Keep the soil moist.
4. Observe the notches along the leaf margin every day and record what you see.

Observation and conclusion: the buds in the notches of the leaf margin develop into tiny plantlets with roots and leaves. Each bud can give rise to a new plant, so a leaf is a vegetative part that can reproduce the plant.

Activity 3: Potato pieces on wet cotton

1. Observe the surface of a potato and find the notches or eyes.
2. Cut the potato into small pieces, so that some contain a notch or bud and some do not.
3. Spread wet cotton on a tray, place the pieces on it, and note where the pieces with buds are placed.
4. Keep the cotton moist and observe the pieces over the next few days.
5. Note which pieces give rise to fresh green shoots and roots.

Observation and conclusion: only the pieces with an eye (bud) give rise to shoots and roots, showing that the buds of the stem tuber produce the new plants.

Glossary

• Asexual reproduction — Reproduction by a single parent, without the fusion of gametes, producing offspring that are almost exact copies of the parent.
• Sexual reproduction — Reproduction involving two parents, a male and a female, whose gametes fuse to form a zygote.
• Vegetative propagation — Asexual reproduction in plants in which new plants arise from roots, stems, leaves or buds instead of seeds.
• Vegetative bud — A bud in the axil of a leaf, made of a short stem with immature overlapping leaves, that can develop into a shoot or a new plant.
• Node — The part of a stem or branch at which a leaf arises; it carries a bud in the leaf axil.
• Eye (of potato) — A small scar or notch on the surface of a potato that contains one or more buds.
• Cutting — A piece of a stem with at least one node, planted in soil or kept in water to grow into a new plant.
• Layering — Making a branch form roots while still attached to the parent by burying part of it in soil, then cutting it free.
• Grafting — Joining a stem piece (scion) of one plant to a rooted plant (stock) of another variety so that they grow as one.
• Budding (in horticulture) — A form of grafting in which a single bud of a desired variety is inserted under the bark of a rooted stock.
• Tissue culture — Growing new plants from tissue or cells of a growing tip on a sterile artificial nutrient medium.
• Explant — Any part of a plant taken out and grown in a test tube under sterile conditions in a nutrient medium.
• Callus — The small group of rapidly dividing cells formed when plant tissue is placed on an artificial nutrient medium.
• Totipotency — The capacity of any plant cell or explant to generate a whole plant.
• Micropropagation — The production of thousands of genetically identical plants (somaclones) from one parent through tissue culture.

Common errors and misconceptions

• Misconception: New plants always grow from seeds. Correct: Plants such as sugarcane, potato, rose and banana are grown from vegetative parts; banana, orange, rose and jasmine have even lost the capacity to produce seeds.
• Misconception: The potato is a root. Correct: The potato is a fleshy underground stem; its eyes carry buds, which sprout into new plants.
• Misconception: Any piece of stem will grow into a new plant. Correct: A cutting needs a node with a bud; money plant pieces cut from between two leaves do not grow.
• Misconception: Plants raised by vegetative propagation show new variations. Correct: They are genetically identical to the single parent, so they keep all its characteristics and show no variation.
• Misconception: Tissue culture starts from seeds. Correct: It starts from tissue or cells taken from the growing tip of a plant, grown on a nutrient medium.
• Misconception: Grafting two rose varieties produces a new hybrid by sexual reproduction. Correct: No gametes fuse in grafting; it is asexual, and the scion keeps the characteristics of its own variety.
• Misconception: Only fungi reproduce by spores. Correct: Plants such as mosses and ferns also reproduce by means of spores.

Exam-style questions with model answers

Q1. Name the plant whose leaves bear buds that grow into new plants, and state where the buds are found. [1 mark]

1. Bryophyllum (the sprout leaf plant). Its buds are found in the notches along the margin of the leaf, and each can develop into a new plant on moist soil.

Q2. Name four plants that have lost the capacity to produce seeds. How are they propagated? [2 marks]

1. Banana, orange, rose and jasmine have lost the capacity to produce seeds.
2. They are propagated by vegetative propagation, that is, from their vegetative parts by methods such as cuttings, layering, grafting, budding or tissue culture.

Q3. State three advantages of vegetative propagation. [3 marks]

1. Plants raised by vegetative propagation take less time to grow, and bear flowers and fruits earlier than plants raised from seeds.
2. Plants such as banana, orange, rose and jasmine, which have lost the capacity to produce seeds, can still be propagated.
3. All the plants produced are genetically similar to the parent and have all its characteristics, so a desirable variety is kept unchanged.

Q4. State three disadvantages of vegetative propagation. [3 marks]

1. There is no variation, because the new plants are copies of one parent, so all of them may be affected alike if conditions change.
2. A disease of the parent plant, such as a virus infection, usually passes to the offspring grown from its parts.
3. New plants formed naturally often grow close to the parent and to each other, so crowding leads to competition for space, light, water and minerals.

Q5. Describe how a lemon plant can be propagated by layering. [3 marks]

1. A flexible, thin twig of the lemon plant is selected, and its middle part is bent down and buried under the soil surface while it is still attached to the parent.
2. The soil is watered regularly. After 10 to 15 days, roots develop from the part of the twig buried in the soil.
3. Once the roots have developed, the twig is cut from the parent plant, and it grows as a separate new plant.

Q6. Describe the steps by which a yellow rose can be grafted on to a wild rose. Name the stock and the scion. [4 marks]

1. A healthy rooted wild rose plant is taken as the stock, and a healthy stem piece of the yellow rose is taken as the scion.
2. A wound or slit is made on a twig of the wild rose.
3. The cut stem of the yellow rose is inserted and fitted into the slit, and the joint is wrapped with a cotton cloth or film to keep pests out until it heals.
4. The other branches of the wild rose are cut off, and the plant is watered regularly; the yellow rose then grows on the roots of the wild rose.

Q7. In an activity, some money plant pieces had at least one leaf, and others were cut from between two leaves. All were dipped in water. State and explain the result. [4 marks]

1. The pieces with a leaf grow roots and give rise to fresh leaves after a few days.
2. The pieces cut from between two leaves do not grow.
3. A piece with a leaf includes a node, which carries a vegetative bud in the leaf axil; this bud can develop into a new shoot, and roots form from the stem.
4. A piece from between two leaves is only an internode, with no bud, so it does not grow into a new plant. Conclusion: a stem cutting must include a node.

Q8. What is tissue culture? Describe its basic steps, and give two advantages of micropropagation. [5 marks]

1. Tissue culture is a method of artificial propagation in which new plants are grown from tissue or cells taken from the growing tip of a plant, on a sterile artificial nutrient medium.
2. Steps: tissue is removed, or cells are separated, from the growing tip. It is placed on a sterile nutrient medium containing sucrose, salts, vitamins, amino acids and growth regulators. The cells divide rapidly to form a small group of cells called a callus.
3. The callus is transferred to another medium containing hormones for growth and differentiation, where it forms plantlets.
4. The plantlets are placed in the soil to grow into mature plants.
5. Advantages: thousands of plants can be produced from one parent in a very short time, and the plants are disease-free; for example, virus-free banana plantlets are produced from the shoot tip.

Q9. Explain natural vegetative propagation by stems, roots and leaves, with one example of each. [5 marks]

1. In natural vegetative propagation, a vegetative part of the plant forms a new plant by itself, without seeds, and the new plant is genetically identical to the parent.
2. Stem: the potato is a fleshy underground stem whose eyes carry buds; when a piece with an eye is placed in moist soil, the bud sprouts into shoots and roots. Grass also spreads by runners that root at their nodes.
3. Root: the swollen, food-storing roots of Dahlia (and of sweet potato) give rise to new plants.
4. Leaf: Bryophyllum bears buds in the notches along its leaf margin; when a leaf falls on moist soil, each bud develops into a new plant.

Key takeaways

• Asexual reproduction involves a single parent and gives genetically identical offspring; sexual reproduction involves two parents, a male and a female, whose gametes fuse.
• The types of asexual reproduction include binary fission (Amoeba), budding (yeast, Hydra), fragmentation (Spirogyra), spore formation (Rhizopus), vegetative propagation and tissue culture.
• Vegetative propagation produces new plants from roots, stems, leaves or buds; the vegetative bud in a leaf axil at a node can grow into a new plant.
• Natural examples include potato eyes, ginger, grass runners, Chrysanthemum suckers, Dahlia and sweet potato roots, and the leaf buds of Bryophyllum.
• Gardeners and nurseries use cuttings (rose, money plant, sugarcane), layering (lemon, jasmine), grafting (rose varieties, grapes) and budding (rose).
• Vegetative propagation gives earlier flowers and fruits, allows seedless plants such as banana and orange to be grown, and keeps all the parent's characteristics.
• Its disadvantages are that there is no variation, diseases of the parent pass to the offspring, and new plants may be crowded.
• In tissue culture, cells from a growing tip form a callus on a sterile nutrient medium, then plantlets on a medium with hormones, which are then planted in soil.
• Micropropagation produces thousands of genetically identical, disease-free plants (somaclones) quickly, and meristem culture gives virus-free banana, sugarcane and potato.

Test yourself

What are the vegetative parts of a plant?

The roots, stems and leaves are the vegetative parts of a plant; the flowers are the reproductive parts.

What are the "eyes" of a potato?

They are small scars or notches on the surface of the potato that contain buds, which can sprout into new shoots and roots.

Which part of a Dahlia plant is used to grow new plants?

Its swollen, food-storing tuberous roots, planted with a piece of the old stem base, give rise to new plants.

Why must a stem cutting include a node?

The node carries a vegetative bud in the leaf axil, and this bud grows into a new shoot; a piece of stem without a node usually does not grow.

In grafting, what are the stock and the scion?

The stock is the rooted plant that supplies the roots, and the scion is the stem piece of another variety joined to it.

What is a callus in tissue culture?

A callus is the small group of rapidly dividing cells formed when tissue from a growing tip is placed on an artificial nutrient medium.

Name two growth regulators added to the nutrient medium in tissue culture.

Auxins and cytokinins are growth regulators added to the medium, along with sucrose, inorganic salts, vitamins and amino acids.

Why are tissue-cultured banana plantlets valued by farmers?

They are mass-produced from the virus-free shoot tip (apical meristem), so they help eliminate virus-infected plants and give high yields.