Tuber

Bulb

Rhizome

Corm

Stolon

Runner

Offset

Vegetative propogation

Vegetative propogation

Atificial Vegetative Propagation Stem Cutting1)Cutting the stem of the plant

2) Placing the cut stem into a moist mud pot 3)Development of roots

Grafting

Grafting Whip Grafting

Cleft Grafting

Grafting

Bud Grafting

Bud Grafting

Bud Grafting

Layering

Mound Layering

Aerial Layering

Aerial layering

Advantages of vegetative propagation

Easier, less expensive and rapid Seedless plants can be reproduced by this method New individual produced possesses exact qualities of parents. Flower produced are of superior quality. Desired character of fruits can be maintained.

Sexual PropagationVegetative PropagationSlow, uncertain, less economicQuicker, more certain, more economicSeeds are viable and strong to face environmentSeeds are less viable and less strong.Seedless plants cannot be reproduced by this methodSeedless plants can be reproduced by this method

Parenteral characteristic are not retainedParenteral characteristic are retained

New varieties are possibleNew varieties are not possible

Due to dispersal of fruits and seeds overcrowding does not take place Overcrowding take place. No dispersal of fruits and seeds

Economic importance of vegetative propagation

By growing desired variety of a plant in large number: Vegetative propagation Micro propagation By evolving new varieties of plant with desired characterstic: Hybridisation

Hybridisation Means crossing of two plants having desired characteristic and bringing together of these useful character into a new plant called the hybrid

Hybridisation

Hybridisation

Steps of artificial cross pollination

Choosing the variety with desired characteristic

Anther is removed which is called as emasculation

Stigma of this flower are dusted with pollen grains from desired characteristic.

It gives rise to a hybrid

Somatic Cell Hybridization

Step of somatic hybridisation

Removing cell wall of plant cell ( Protoplasts)

Protoplasts are fused with the help of certain chemicals which leads to formation of somatic hybrid by fusion of nucleus( hetrokaryon)

Somatic hybrid is made to grow in suitable medium where it regenerates cell wall to form plantlets

Advantages of Hybridisation

Production of hybrid which cannot be produced by sexual method Obtaining clones For introducing useful gene in case of male sterility

Advantages of Hybridisation

It helps in producing crops that have: Higher yield Increase in size and number of fruits Resistance to various disease Better ability to survive

Advantages of Hybridisation

Hybrid is superior to parent plant Common method for creating genetic variation for experiment and research.

Micro propagation

Terms involved in Micropropagation

Explant : Plant whose parts are detached and used for plant cultureCulture medium: Artificial medium that contains nutrients like vitamins, minerals and hormones like auxins and cytokinnsCallus: Cell growth Plantlets: Small plants

Steps of Micro propogation

A small piece of tissue generally from shoot tip is taken

It is grown in the nutrient medium which contains essential nutrients, hormones, vitamins

The cells grow into unorganized mass callus

Steps of Micro propogation

Cells differentiate into roots and shoots and plantlets are formed

Plantlets are transferred to soil and grown to maturity

Disadvantages of micro propagation

Tedious process Expensive Needs sterile condition

Uses of bio technology

Uses of bio technology

Enzymes

Uses of genetic engineering

Uses of genetic engineering

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