1. PLANT HORMONES
Prof. Ms. Vrushali S. Dighe Department Of Botany S. M. Joshi College, Hadapsar, Pune.

2. What is plant physiology?
What is plant anatomy?
ANATOMY: study of the structure of organisms… looking at cells, tissues
(Morphology: Study of form)
What is plant physiology?
PHYSIOLOGY: study of the function of cells, tissues, organs of living things;
and the physics/chemistry of these functions…

3. “Structure correlates to function”
Always keep in mind that in plant anatomy, morphology & physiology…
“Structure correlates to function”

4. Plant Hormones Chemical compounds produced by plants
Effective at very low concentrations
Five major hormone groups are:
Auxins
Gibberellins
Cytokinins
Abscisic Acid
Ethylene

5. 1. AUXINS Promote cell growth Involved in gravitropism
and phototropism
Control fruit development

6. 2. Gibberellins 3. Cytokinins 4. Abscisic Acid Promote stem elongation
Promote cell division and
organ differentiation
4. Abscisic Acid
Promotes seed dormancy
Causes stomata closing

7. 5. ETHYLENE Gaseous hormone, very simple formula (C2H4)
Ethylene promotes
fruit ripening!
Air Ethylene

8. “One rotten apple spoils the barrel”
Why?
Probably due to ethylene!
Rotten apple producing
lots of ethylene!
Autocatalytic
As a response to injury

9. Avocado ripening…
Place in a paper bag, with a ripe banana!