flower development

1. ABC model of flower development
Jatindra Nath Mohanty, PhD scholar
Regd no - 1581611002

2. What is a flower?
Flower is the reproductive part of the plant
developed from vegetative meristem

3. Metamorphosis of plant
• It involves 3 physiological changes
(a) Transition towards flowering
(b) Inflorescence
(c) Individual floral organ development

4. (a)Transition towards flowering
• The transition from the vegetative phase to reproductive
phase involves a dramatic change which contains both
endogenous and exogenous elements:
• Eg- leaves(biomass) , photoperiod, hormones
• In molecular biology this state is control by
Genes in Arabdopsis thaliana: FLOWERING LOCUS
T (FT), LEAFY (LFY), SUPPRESOR OF OVEREXPRESSION OF
CONSTANS1 (SOC1)

5. (b) Inflorescence
• Inflorescence or floral meristem formation
depends on cell fate determination
mechanism.
• In floral meristem development certain gene
in veg. meristem negatively regulate the
possible differentiation of the stem cells.
• Eg-WUS gene , SHOOTMERISTEMLESS (STM)
gene etc.

6. (c) Individual floral organ
development
The flower arises from the activity of three classes of
genes, which regulate floral development: meristem
identity gene, organ identity gene and cadastral gene

7. MOLECULAR AND DEVELOPMENTAL
BIOLOGY ON FLOWER DEVELOPMENT

8. ABC model

9. ABC genes & their control
AP3 & PI AGAP1 & AP2

10. wild type and mutant gene analysis

11. Function of D class of gene
Function D specifies the identity of the ovule
Eg-FLORAL BINDING PROTEIN7 (FBP7) and
FLORAL BINDING PROTEIN1L (FBP1l).

12. Conclusion
• The ABC classes of gene act alone, or with
combination to specify the four types of floral
organ.
• The ABC genes are sufficient to convert
vegetative meristem to floral meristem and
finally flowers are generated.
• The ABC model is applicable to all flowering
plants.

13. Thank you