organogenesis - dr amit kr dutta
TRANSCRIPT
Organogenesis
Dr. Amit Kumar Dutta, Ph.D
The Explant develops into callus tissue in a medium containing either a particular concentration of Auxin or definite Auxin- Cytokinin ratio.
Organogenesis
The Production of Adventitious roots & shoots from cells of tissue culture is called Organogenesis.
Organogenesis
Look Back Before……………..!
F. Skoog (1944)
First Indicate that In-vitro organogenesis could be chemically regulated to some extent.
F. Skoog & C Tsui (1948)
Adenine sulphate – active in promoting Shoot Initiation.
Reversed Inhibitory effect of Auxin.
F. Skoog & C. O. Miller (1957)
Organogenesis is controlled by a balance between Auxin & Cytokinin (Hypothesis)
J. G. Torrey (1966)
Organogenesis in the callus tissue starts with the formation of clusters of meristematic cells
(Hypothesis)
Look Back Before……………..!
T. A. Thorpe (1980)
Advanced StudyKey factor of Organogenesis is the ratio of
Endogenous Auxin – Cytokinin.
N. Everett (1982)
Endogenous Ethylene was identified as a factor in the induction of shoot buds from cultured
tobacco cotyledons.
Look Back Before……………..!
Organogenesis means the development of adventitious organs or primordia from undifferentiated cell mass in tissue culture by the process of differentiation.
Organogenesis
Factors ..…….!
Size of Explant
Source of Explant
Seasonal Variation
Quality & Intensity of Light
Oxygen Gradient
Temperature
Plant Hormones
Factors ..…….!
Agar- Agar
pH of the Medium
Ploidy Level
Age of Culture
Factors ..…….!
Size of Explant
Organogenesis is basically dependent upon the size of
the explant.
Source of Explant
Important in determining the potential of Organogenesis.
The rate of shoot formation on cotyledons is correlated with the growth rate of the parent tree and with the size of the seed.
Seasonal Variations
Effect of it on Plant is another factor which exercises an influence on organ formation.
Oxygen Gradient
Shoot Bud formation takes place when the gradient of available oxygen inside the culture vessel is reduced.
Rooting requires a high oxygen gradient.
Quality & Intensity of Light
Play an important and effective role in the promotion of organogenesis.
Artificial fluorescent light favours rooting and inhibits in others.
Temperature
TC normally grown successfully at 250C. Number of Bulbous species, the Temperature may be lower 150C.
Tropical species require Higher temperatures : 27- 300C.
Importance ..…….!
Regeneration of Plant from Cell and Callus Culture via Organogenesis.It a wide field of Plant Science.Importance & Applications of Organogenesis are vast & varied.
Conti……..
Uniqueness of cellular and molecular genetics in higher plants is dependent upon the potential for regeneration of the plants from cell cultures via Organogenesis.
Importance ..…….!
Conti……..
The success of genetic engineering of higher plant, clonal multiplication of new genotype, somatic hybridization via fusion & isolation of mutants from single cell and callus culture.
Importance ..…….!
Thank You…!
Any Difficulties Contact to Respective
Teacher…….!