Micro-propagation.pdf

Clonal propagation invitro is called micropropagation.In micropropagation, apical meristem is cultivated. so this technique is also known as meristem culture or mericlones.Webber used the word ‘clone’for first time to apply for cultivated plants that were propagated vegetatively.It indicates that plants grown from such vegetative parts are not individuals in the ordinary sense, but are simply transplanted parts of the same individual and such plants are identical.

1. A plant tissue culture technique
Micropropagation
-By Shweta Tiwari

2. The culture of plant seeds,
organs, tissues, cells, or
protoplasm on nutrient
media under sterile
conditions.
PLANT TISSUE CULTURE

3. BASIS FOR PLANT TISSUE CULTURE
Auxin: Stimulates Root Development
Cytokinin: Stimulates Shoot Development
Auxin ↓Cytokinin = Root Development
Cytokinin ↓Auxin = Shoot Development
Auxin = Cytokinin = Callus Development
Two Hormones Affect Plant Differentiation:
Generally, the ratio of these two hormones can
determine plant development:

4. 01
Micropropagation
03
02
Germplasm Preservation
04
Somaclonal variation
Breeding Applications of Tissue
Culture
05
05
In vitro Hybridization-
Protoplast fusion
Haploid Production
Embryo Culture

5. Micropropagation
In vitro Clonal Propagation.
Micropropagation is the practice of
rapidly multiplying stock plant
material to produce a large number
of progeny plants, using modern
plant tissue culture methods

6. CLONE
Clone is a plant population derived from
a single individual by asexual
reproduction.
Clonal Propagation is the multiplication
of genetically identical individuals by
asexual reproduction

7. Features of Micropropagation
Clonal reproduction
Multiplication stage can be recycled
many times to produce an unlimited
number of clones
Easy to manipulate production cycles
Disease-free plants can be produced

8. From cells, tissues or organs
Cultured aseptically on defined media
Contained in culture vessels
Maintained under controlled conditions of light and temperatur
Rapid clonal in vitro propagation of plants:

9. Commercialization of Micropropagation 1970s & 1980s
Murashige (1974)
Broad commercial application

10. Starting
material for
Propagation

11. Selection of plant material
01 Part of plant
02 Genotype
03 Physiological
Condition
04 Season
05 Position on plant
06 Size of Explant

12. 01
Mineral
03
02
Sugar
04
Organic growth factor
Medium
05
05
Other Additives
Gelling Agent
Growth Regulator

13. Physical
Environment
TEMPERATURE
MOISTURE
LIGHT

14. STAGES
1. Selection of plant material
2. Establish aseptic culture
3. Multiplication
4. Shoot elongation
5. Root induction / formation
6. Acclimatization

15. Step of Micropropagation
Stage I –Establishment
Selection of the explant plant
Sterilization of the plant tissue takes place
Establishment to growth medium

Stage II  - Proliferation
Transfer to proliferation media
Shoots can be constantly divided

Stage III – Rooting & Hardening
explant transferred to root media
explant returned to soil

16. Organogenesis via callus formation
Direct adventitious organ formation
Direct embryogenesis
Indirect embryogenesis
Meristem culture (Mericloning)
Bud culture
Organogenesis
1.
2.
Embryogenesis
1.
2.
Microcutting
1.
2.
Methods of Micropropagation

17. Organogenesis
PGRs are prob. the most important factor affecting organogenesis
The central dogma of organogenesis:
1. Cytokinins tend to stimulate formation of shoots
2. Auxins tend to stimulate formation of roots
1. a high cytokinin:auxin ratio promotes shoots and inhibits roots
2. high auxin:cytokinin ratio promotes roots and/or callus
formation while inhibiting shoot formation

18. Organogenesis
The process of initiation and development of a structure that
shows natural organ form and function.
The ability of non-meristematic plant tissues to form various
organs de novo.
The production of roots, shoots or leaves.
These organs may arise out of pre-existing meristems or out of
differentiated cells.
This, like embryogenesis, may involve a callus intermediate but
often occurs without callus

19. Tissue culture maintains the genetic of the
cell or tissue used as an explant.
Tissue culture conditions can be modified to
cause to somatic cells to reprogram into a
bipolar structure.
These bipolar structures behave like a true
embryo - called somatic embryos
An Embryo is made up of actively growing
cells and the term is normally used to
describe the early formation of tissue in the
first stages of growth.
Somatic Embryos

20. The process of initiation and
development of embryos or
embryo-like structures from somatic
cells
The production of embryos from
somatic or “non-germ” cells.
Usually involves a callus
intermediate stage which can result
in variation among seedlings
Somatic Embryogenesis

21. The composition of the culture medium
controls the process-
auxin (usually 2,4-D) added causes
induction, the formation of
embrygogenic clumps or
proembryogenic masses (PEMs)
(induction medium)
auxin is deleted and the clumps become
mature embryos (maturation medium)

22. early cell division doesn't follow a
fixed pattern, unlike with zygotic
embryogenesis
later stages are very similar to
zygotic embryos (dicot pattern)
Stages of development
–globular stage (multicellular)–heart-shaped stage (bilateral symmetry)
–bipolarity–torpedo-shaped stage – consists of initial cells for the
shoot/root meristem

23. Stages of Somatic embryo development

24. Somatic
Embryogenesis
Stimulation of callus or
suspension cells to
undergo a
developmental pathway
that mimics the
development of the
zygotic embryo

25. Advantages
From one to many propagules rapidly.
Multiplication in controlled lab conditions.
Continuous propagation year round.
Potential for disease-free propagules.
Inexpensive per plant once established.

26. Disdvantages
Specialized equipment/facilities required.
More technical expertise required.
Protocols not optimized for all species.
Plants produced may not fit industry standards.
Relatively expensive to set up.

27. Micropropagation Limitations
Equipment/facility intensive operation
Technical expertise in management positions
Protocols not optimized for all species
Liners may not fit industry standard
Propagules may be too expensive

28. Applications
Rapid increase of new varieties.
Elimination of diseases.
Cloning of plant types not easily propagated by
conventional methods.
Propagules have enhanced growth features
(multibranched character;Ficus, Syngonium)

29. Thank You