gite for topic dr.k.suresh gide for theaching dr. p. backiya raj sir

1. DEVELOPMENTAL BOTANY
IN
SEED DEVELOPMENT
M. CHINNAKARUPPAN
19PGBY04
I- M.Sc., Botany
S.N.College, Perungudi.
Dr. K. SURESH M.Sc., M.Phil., Ph.D.
Assistant Professor
department of Botany
S.N.College, Perungudi.

2. Definition of Seed
• Seed was fertilized mature ovule.
• Seeds are unit of the reproduction of a flowering plant, which is
capable of developing into a single plant.
• In some species of plant, like walnuts, groundnuts, and
chickpeas, seeds are also used as sources of food.
• The plumule is present in the seed embryo, which develops into
a new plant.
• After fertilization that is post fertilization ovule developed from
seed.
• The seeds are innumerable variation in size, shape, color and
surface.
• The seed size from tiny dust particle found in orchid (25
milligram) to large double coconut – Lodoicea maldivica (6 kg )
• The seeds are differentiated into species to species

3. Structure and development of seed
• A fully grown and developed seed has three primary
parts: the embryo, endosperm, and seed coat.

4. Endosperm
• Fertilized and developed polar nuclei are called endosperm. This
fertilization was double fertilization and treble fusion.
• The endosperm was most important plant product on humans.
• The endosperms are used for food and food materials in cooking oil, rice in
also.
• Endosperm is the most common nutritive tissue for the developing embryo
in angiosperm.

5. Types of endosperm
Nuclear endosperm
• This endosperm the further division are
not followed by wall formation.
• Present in free nuclear stage.
Cellular endosperm
• This endosperm the further division are
immediate wall formation.
• Absence of free nuclear stage

6. Helobial endosperm
• This endosperm was intermediate structure.
Present in nuclear and cellular type.
Ruminant endosperm
• Mature endosperm with any degree of irregular
and unevenness in its surface contour is called
Ruminant endosperm

7. Embryo
• The fertilized egg is called zygote. Following a
predetermined mode of development it gives rise to
embryo.

8. Types of embryo
Dicot embryo
• The embryo containing two
cotyledons is called dicot embryo
Monocot embryo
• The embryo containing only one
cotyledons is called monocot embryo

9. Seed coat
• The ovule develops into seed. The integuments
mature into seed-coat
• The ovule has either two integuments or just one.
• The inner integument was companied as 4 zones
and outer integument was developed from fibers in
cotton plant
Function of seed-coat
• Protect by embryo and endosperm.
• Help into dispersal of seed
• Provide nutrition to the developing embryo

10. Types of seed
Albuminous or endospermous seed
• Where are endosperm is present as in
cereals and castor-bean
Ex-albuminous or non-endospermous
seed
• Where are endosperm is absent as in
beans and cucurbits

11. Dicot seed
Monocot seed

12. Importance of seed
• Seeds are helps into spread and mulltify species in
all the areas
• Some seeds are used for food and food materials in
all animals in humans.

13. Dispersal of seed
• Seed Dispersal is an adaptive mechanism in all
seed-bearing plants, which is involved in the
movement or transport of seeds away from their
parent plant to ensure the germination and survival
of some of the seeds to adult plants.
• There are two main modes of seed dispersal in
autochory and allochory.

14. Autochory
• Autochorous plants disperse their seed without any
help from an external vector, as a result this limits
plants considerably as to the distance they can
disperse their seed.

15. Gravity dispersal
• The plant use of gravity for dispersal is a simple means of achieving
seed dispersal. The effect of gravity on heavier fruits causes them to
fall from the plant when ripe.
• Gravity dispersal also allows for later transmission by water or
animal.

16. Ballistic dispersal
• This type of dispersal where the seed is forcefully ejected
by explosive dehiscence of the fruit. Often the force that generates
the explosion results from turgor pressure within the fruit.
• The explosions are powerful enough to throw the seed up to 100
meters.

17. Allochory
• Allochory refers to any of many types of seed
dispersal where a vector or secondary agent is used
to disperse seeds.

18. Wind dispersal
• Wind dispersal mechanisms, have a feathery like
structure is attached to their seeds and can be
dispersed long distances.

19. Water dispersal (or) hydrochory
• Seeds can travel for extremely long distances,
depending on the specific mode of water dispersal.

20. Ant dispersal (or) myrmecochory
• Ants carry such seeds into their colonies, feed the
elaiosome to their larvae and discard the otherwise
intact seed in an underground chamber

21. Animal’s dispersal (or) zoochory
• Animals can disperse plant seeds in several ways,
• Which a plant surrounds seeds with an edible, nutritious fruit as a
good food for animals that consume it. Birds and mammals are the
most important seed dispersers,

22. Human’s dispersal (or) anthropochory
• Dispersal on human clothes (up to 250 m), on shoes
(up to 5 km), or by cars (regularly ~ 250 m, singles
cases > 100 km).

23. Conclusion
• Seed is very important source in the world.
• This world is coverd by a varius type of plant in the
plants are germinate into the seed.
• Seeds are always used for food in humans.