Download to read offline
More Related Content
Similar to Asextual production ppt
Asextual production ppt
- 1.
- 2. • Asexual reproductionproduces identical offspring. • Only one parent is needed in asexual reproduction, and the offspring produced are genetically identical.
- 3. Asexual Reproduction inPlants Asexual Reproduction: •It does not involve the formation of gametes. New organisms are formed either by the division of the parent body or by the differentiation of the parent body. •Asexual reproduction occurs through, 1. Budding 2. Binary fission 3. Spore formation 4. Vegetative Propagation – The roots, stems and leaves are called vegetative parts of a plant. When any of these give rise to new plants, it is called vegetative reproduction.
- 4. Modes of AsexualReproduction Budding • Budding is commonly found in yeast cells. The bud is formed on the body of the parent, gets detached and forms a new individual. Binary Fission in Bacteria: • Bacterial binary fission is the process that bacteria use to carry out cell division as shown below. Spore formation: • In plants like ferns, spores are formed on the underside of the leaves. These are capable of developing into new plants when they are carried by the wind to other places with suitable conditions for growth. Fragmentation Spirogyra breaks into smaller pieces on maturation and each fragment grows into a new individual. • Vegetative reproduction by roots • When sweet potatoes, asparagus, carrot are buried in the soil, they give rise to new plants.
- 5. Vegetative reproduction bystems Tuber: • Example: Potato, The ‘eyes’ are actually buds which give rise to new plants. If a piece of potato without the ‘eye’ portion is planted, it cannot develop into a new plant. Rhizome: • Example: Ginger also gives rise to new plants from buds on the stem. It has nodes and internodes and thin dry papery scaly leaves. Bulbs of onion: • This has a thick short stem in the form of a condensed disc covered by scale leaves. The disc has buds which can grow into new plants. • Some plants have horizontal stems. Roots and shoots develop at the nodes to form new plants. • Example: Mint, grass.
- 6. Vegetative reproduction byleaves • Bryophyllum bears buds on its leaf margins. When these fall on the ground, they develop into new plants.
- 7. Artificial Vegetative Propagation Cutting •Cutting is removing a part of the stem and planting it into the soil to allow the growth of roots and buds. • Example: Sugarcane, rose, china rose, pears. Layering: • The lower branch of a plant is selected and a ring of the bark is removed from the stem. The portion where the bark is removed is bent and covered with soil. The branch is kept covered with the soil for a few days during which new roots start to develop on the branch. The branch is then cut off from the parent plant and allowed to grow as an individual plant. • Example: Hibiscus, jasmine, rose, bougainvillea. Grafting: • A small branch is cut from the plant to be grown with a wedge-shaped end. This is called scion. Now a V-shaped cut is made in the stem of a rooted plant called stock. The scion is now fitted into the stock and they are taped together. Soon the graft becomes part of the rooted plant. Tissue Culture: • Tissue culture is one of the ways of cloning plants. It works with small pieces of plants, called explants.
- 8. • Advantages ofvegetative reproduction or vegetative propagation 1. Useful to grow seedless varieties. 2. Faster and easier than the natural process. 3. The only method of reproduction for plants which do not produce seeds Example: Banana and rose 4. Offspring resemble the parent exactly.
- 9. • Disadvantages ofvegetative reproduction or vegetative propagation 1. Being identical in all respects, these plants may be prone to disease at the same time. 2. Dispersal cannot occur naturally so there tends to be overcrowding.
- 10.