Seed technology concept, Seed formation, Structure, types of seed germination, role, goals and classes of seeds”.

1. Topic
on
“Seed technology concept, Seed formation, Structure, types
of seed germination, role, goals and classes of seeds”
Department of Agriculture Botany

2. What is Seed ?
 An embryonic plant enclosed in a protective outer covering.
 A fertilized mature ovule consisting of the embryo, stored material,
and protective coats.
 The basic unit of Agriculture.
Seed Technology
 “Seed technology is the science dealing with the methods of improving
physical and genetical characteristics of seed.
 It involves such activities as variety development, evolution and release
of varieties, seed production, seed processing, seed certification and
storage.

3. S.N. Seed Grain
1 Used to Growing plant Consumption
2 Necessary Genetic Purity and Seed
viability
Not Necessary
3 Important Embryo Endosperm
4 Compulsory Certified Not compulsion
5 Treated with Fungicide and pesticides Not treated with
• What is the difference between Seed and grain ?
 Seed viability- Ability of embryo to germinate, and is affected by a
number of different conditions (flooding, heat, pathogen, etc.)
Concept of seed technology

4. • Pollination
• Fertilization
• Double fertilization - when both male and female gametophytes are fully mature.
This usually occurs in a dual fusion process.
• A seed is formed when fertilized ovule divides by mitosis.
S.N. Pollination Fertilization
1 Transfer of pollen grains from the male
anther of a flower to the female stigma.
Fusion of male and female
gamete.
2 Physical process Cellular, genetic, and
biochemical process.
3 Occurs- early stage of sexual reproduction After pollination.
 What is Seed Development?
• The process by which seeds are formed from the end of fertilization to
the production of a mature seed body.
How to Seed Formation?

6.  Seeds of different plants may vary in many ways, but the basic anatomy remains
the same.
 A typical seed consists of the following parts:
 Testa: It is the outer coat of the seed that
protects the embryonic plant.
 Micropyle /(tiny pore): Small opening of
present in seeds through which water enters
them.
 Present- ovule of seed.
 Radicle: It is an embryonic root that will develop into the primary root of the plant.
 It is 1st part of the embryo to push its way out of the seed during germination.
 Cotyledon: In some plants, this contains high quantities of starch and will provide
a source of food for the developing embryo to germination.
In other plants this role is performed by an endosperm.
Structure of Seed

7.  In monocotyledons, there is just one cotyledon whereas in dicotyledons there are two .
 Monocotyledons- (Non-legume/cereals)
 Contain only one embryonic leaf.
 e.g. Wheat, Bajra, Okra, Maize etc.
 Dicotyledons- (Legume/cereals)
 Contain two embryonic leaf.
 e.g. Pea, Tur, groundnut, green gram etc.
 Polycotyledon-
 Contain more than two embryonic leaf.
 e.g Pine.

8.  Depending on the type of germination (epigeous or hypogeous) the cotyledons may
remain below ground or be pulled above ground.
 Seed germination required optimum 25-300 C temperature.
 There are 3 types of seed germination.
1. Epigeal (Epi- Above/ out of soil)
 e.g Bean, cotton, Onion etc. (Mostly – dicot seeds).
2. Hypogeal (Below)
 e.g Wheat, Rice, Maize, etc.
 (mostly- monocot seeds but, In dicot- gram, groundnut, Mango).
3. Viviparous (inside fruit)-
 Seed that develops into a seedling before it separates from the parent plant.
 e.g Coconut, Date palm, Tomato.
Type of Seed germination

9. • Epigeal
• Hypogeal
• Viviparous

10. 1. External Factors
• Water
• Air
• Temperature
• Light - a) Light Intensity.
b) Light Quantity.
2. Internal Factors
• Food Auxin
• Seed Viability/ Vigor/Quality
• Genetic
• Seed complete its resting period

12. Role of seed technology
1. Improved seed – a carrier of new technologies-
 Introduction of quality seeds of new varieties significantly increase yield levels.
 In India, the cultivation of high yielding varieties have helped to increase food
production from 52 million tonnes to nearly 180 million tonnes over a period of 40
years.
2. Improved seed – a basic tool for secured food supply. (Bez. rapid increase in
population)
3. Improved seed – the principal means to secure crop yields in less favourable
areas of production.
• The supply of god quality seeds of improved varieties suitable to these areas is
one of the important contribution to secure higher crop yields.
4. Improved seed – a medium for rapid rehabilation of agriculture in cases of
natural disaster.
• In case of floods and drought affected areas the Govt. will provide the
improved seeds from national seed stocks to rehabilate the agricultural production of
foods grains in the country.

13. Goals of Seed Technology
Increase
Agricultural
Production
Reasonable
price
Rapid
multiplicat
ion
Timely
supply
Assured
high
quality of
seeds
Developed by the Plant Breeders
Planting schedule of farmer is not disturbed
Cost of high quality seed should be
with in reach of the average farmer.

14. Classes of seeds
Nucleus/
Breeder
Foundation
/ Mother
Registered
Certified
Truthful

15. Seed Class Progeny of Tag
Colour
Tag Size
(cm)
Genetic
Purity
Quality
check by
Use for Seed
Prodn of
1 Nucleus Breeder
Originated
- - 100 % Breeder
only
Breeder
2 Breeder Nucleus seed Golden
Yellow
12 x 6 100 % Plant
breeder
Foundation
3 Foundation/
Mother
Breeder seed White 15 x 7.5 99.5 % SCA,
NSC,
SSCA.
Certified /
Registered
4 Registered Foundation
seed
Purple 15 x 7.5 - SSCA -
5 Certified Foundation
seed
Blue 15 x 7.5 99.0 % SSCA,
Pvt. Sector
Source for
farmer
commercial
crop Prodn
6 Truthful Foundation
seed
Green 15 x 10 99.0 % Any
Agency/
Farmer
Used in
private seed
company
 Seed certification agency (SCA)
 National Seed Corporation (NSC)
 State Seed Certification Agency (SSCA)
 In India registered seed is not practiced and certified seed is produced from foundation seed.

16.  Seed lot certification colour – Green/ Orange.
 Seed sample certification colour – Blue.
 Farmer grown which type of seed and its Tag colour ?

17.  The production of a particular class of seed from specific class of seed up to
certified seed stage. This basically depends upon
 The rate of genetic deterioration, Seed multiplication ratio and Total seed demand.
 Based on these factors different seed multiplication models may be derived for each
crop.
 Seed multiplication agency should decide how quickly the farmers can be
supplied with the seed of newly released varieties after the nucleus seed stock has
been handed over to the concerned agency, so that it may replace the old varieties.
 Given the basic factors, the chain of seed multiplication models could be.
 In India 3rd generation seed production.
1. Three - Generation model
Breeder seed - Foundation seed - Certified seed
2. Four - Generation model
Breeder seed - Foundation seed (I) Foundation seed (II) - Certified seed
3. Five - Generation model
Breeder seed - Foundation seed (I)- Foundation seed (II) -Certified seed
(I) - Certified seed (II)
Generation system of Seed
multiplication

18. Q.1. Define Seed and Seed Technology ? Give its scope and importance ?
Q.2. Define seed germination? Enlist its types and explain it with example and
Factors affecting seed germination ?
Q.3. Describe the stages of seed multiplication for seed production of varieties.
Or Describe the Classes of seeds.

19. .
• Related Articles:
• Howard C . Potts (1971) SEEDS - DEVELOPMENT , STRUCTURE AND FUNCTION.
Page.no.37-51.
• The Parts of a Seed and Their Functions in Seed and Plant Development – Cropsreview.com.
• Agarwal, P.K. 1994. Principles of Seed Technology. ICAR, New Delhi.
• Agarwal, P.K. and Dadlani, M. 1986. Techniques in Seed Science and Technology.
South Asian Publishers, New Delhi.
• Agarwal, R.L. 1996. Seed Technology. Oxford and IBH Publication Co., New Delhi.
• Thomson, J.R. 1979. An Introduction to Seed Technology. Leonard Hill, London.