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1. TISSUE CULTURE

2.  The technique of growing plants, seeds and other parts of the plant in
laboratory environment under sterile nutrient medium is
called plant tissue culture.
 The technique of plant tissue culture is based on the concept
of "totipotency".
Different types of tissue culture:-
There are several types of plant tissue culture based on
A) Types of invitro growth:-
*callus culture
*cell suspension culture.

3. B) Types of explant:-
*single cell culture
*root and shoot culture
*anther culture
*embryo culture
*ovule culture
*ovary culture
Callus culture:-
 In callus culture, explant forms callus through cell division
 Callus is irregular unorganized and undifferentiated mass of dividing cells
 Darkness and solids medium containing agar stimulate callus formation
 The medium contain auxins
and BAP(benzyl amino purines) which acts as growth regulators for the stimulation of
all division of explant.
 Callus is obtained with in 2-3 weeks.

4. EXPLANT PART
EXPLANT PART IN
AGAR MEDIUM
GROWTH
OF EXPLANT CALLED
AS CALLUS IN AGAR
MEDIUM

5.  After formation of callus, the medium under goes following changes:
*depletion of nutrients in medium
*gradual loss of water
*accumulation of toxins
 To avoid the above changes, the medium is sub cultured for maintenance
of growth in callus.
 Sub cultured should be repeated after 4-5 weeks.
Cell suspension culture:-
Suspension culture is a type of culture in which single cell/
small aggregates of callus suspended in liquid medium
It is also referred as cell culture.

6. CALLUS CULTURE EXPLANT IN LIQUID MEDIUM CELL CLUMP IN LIQIUD MEDIUM

7. Types of cell suspension culture:-
These are of two types:
*Batch culture
*Continues culture

8. Batch culture:-
In this the cells are grown in a fixed volume of nutrient
culture medium
It involves 5 phases:
i. Lag phase: where cell prepare to divide
ii. Log phase/exponential phase: where cell
start division in drastic number
iii. Linear phase: where the cell division slow but cell
size increased
iv. Decline phase: where the cell size and shape is reduced
v. Stationary phase: where the cell size and shape is
constant

9. Contineous culture:-
 In this culture, a fresh medium is
continuously supplied with nutrient there are the
culture volume is normally constant
 It is further divided into two types
*close continuous culture
*open continues culture