Seed science and technology

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Seed Science and Technology
Preprint · March 2018
DOI: 10.13140/RG.2.2.14540.31369
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SEED SCIENCE AND TECHNOLOGY
Dr. Vishwanath Koti. Assitant Professor, Seed Science and Technology
University of Agricultural Sciences, GKVK, Bangalore-560065
vishwakoti@gmail.com
Evolution of Seed
The evolution of plants has resulted in increasing levels of complexity, from the earliest
algal mats, through bryophytes, lycopods, ferns to the complex gymnosperms and angiosperms
of today. While the groups which appeared earlier continue to thrive, especially in the
environments in which they evolved, each new grade of organisation has eventually become
more "successful" than its predecessors by most measures.
1. Evidence suggests that an algal scum formed on the land 1,200 million years ago
2. To thrive and to avoid extinction, plant are made mechanisms and evolved seed plant during
200 million years ago
3. The latest major group of plants to evolve were the grasses, 40 million years ago
4. The grasses, as well as many other groups, evolved new mechanisms of metabolism to
survive the low CO2 and warm, dry conditions of the tropics over the last 10 million years.
SEED DEVELOPMENT, MATURATION AND SEED STRUCTURE
A true seed is defined as a fertilized mature ovule consisting of embryo, stored food
material and protective coats.
The important events involved in seed development and maturation include
1. Pollination
2. Fertilization
3. Development of the fertilized ovule by cell division
4. Accumulation of reserve food material
5. Loss of moisture content.
1. Pollination
The mature anthers dehisce and release pollen -grains (haploid microspores). When pollen
grains are transferred from an anther to the stigma of the same flower the process is called self-

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pollination or autogamy. If they are transferred to the stigma of another flower, cross-
pollination or allogamy is said to have occurred.
Self-pollination occurs in those plants where bisexual flowers achieve anther dehiscence and
stigma receptivity simultaneously called as chasmogamy. The majority of angiosperms bear
chasmogamous flowers.
In some plants, flowers do not open before pollination such flowers are called
cleistogamous, and this is the most efficient floral adaptation for promoting self-pollination.
Cross-pollination is ensured in plants which bear unisexual flowers. In bisexual flowers also
self-pollination may be prevented by
a. Self-sterility : inability to produce viable pollen Eg:Sunflower
b. Dichogamy: maturation of male and female organs at different times Eg:Bajra
c. Herkogamy : where the structure of male and female sex organs proves a barrier to self
pollination Eg: Lucernae
d. Heterostyly :where flowers are of different types depending on the length of the style
and stigma and pollination occurs only between 2 dissimilar types Eg: Brassica
e. Self incompatibility: Inability to viable pollen to fertilize ovule of same flower Eg: Cole
crops
Self-pollinated crops: wheat, rice, barely, mungbean and cowpea
Cross pollinated Crops: Maize, rye, carrot, cauliflower and onion.
Often cross pollinated crops: cotton and pigeon pea where there may be 10-40 % cross
pollination.
Agents bring about the dissemination of pollen grains
1. Abiotic : wind (anemophily) and water (hydrophily)
2. Biotic including insects (entomophily) and bats (cheiropterophily).
2. Fertilization
After landing on the stigma, the pollen grain germinates and pollen tube grows through
the style. The surface of the stigma secretes substances, which may provide optimum conditions
for pollen germination. The pollen tubes traversing the style pectinase which dissolves
intercellular substances of the style tissue. After traversing the style, the pollen tube enters
embryosac of the ovule. The embryosac consists of 8 cells. The end near the micropyle has the
egg apparatus, which consists of egg cell and 2 synergids. There are 2 polar nuclei in the centre
and the chalazal end has 3 antipodal cells.
In angiosperms, fertilization involves the participation of 2 male nuclei (double
fertilization). One fuses with the egg nucleus to form the diploid zygote and the other with 2
polar nuclei to produce a triploid nucleus, which is the primary endosperm nucleus.

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Diagram to Show the various parts of a fully formed ovule
3. Seed Development
Diagram to Show Development of Seed
1 Embryo Development
The first division of the zygote is transverse in dicots and it results in a small apical cell
and a large basal cell . Cell ca divides vertically forming 2 juxtaposed cells and cb undergoes a
transverse division forming 2 superimposed cells. These results in a T-shaped, 4 celled
proembryo.
Cell ci divides transversely giving rise to n and n'. These 2 cells divide further resulting in
a row of 3 or 4 cells, forming suspensor.
Nucellus

Integuments

Antipodal
cells

Polar
Nuclei

+
Male
Nuclei

à
Triploid
Nucleus
à
Primary
endosperm
Nucleus

Egg
Cell
+
Male
Nuclei
à
Zygote
à
Embryo

Synergid
cells

Funiculus
Micropyle

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Cell m and its derivatives undergo vertical divisions forming a group of 4 to 6 cells. This
group divides by oblique-perclinal wall forming a set of inner cells and a row of outer cells. The
inner cells form the initials of the root apex and the outer cells form the root cap.
The 2 cells formed as a result of the division of ca again divide vertically forming
quadrant. Each cell of the quadrant divides transversely and thus an octant containing 2 tiers of
cell l and p is formed.
The cells of the octant undergo vertical division resulting in a globular proembryo.
Periclinal divisions occur in the peripheral cells of the globular proembryo that delimit an outer
layer, the dermatogen. The tier l gives rise to cotyledons and shoot apex and l forms hypocotl-
radicle axis.
Certain deviations from the above pattern of embryo development are found in different
plants. Different types of embryogeny are distinguished depending on the plane of division of the
apical and the extent of contribution of the basal cell towards embryo development (in some
plants cb remains undivided and does not take part in embryo development at all).
In monocotyledons, the cell cb remains undivided and develops into a haustorial of the
suspension. Cell ca divides into 2 by a transverse division. The terminal cell of these 2 by
repeated divisions in different planes gives rise to a single cotyledon. The embryo development
in grasses is different from that of other monocotyledons. A dorsiventral symmetry is established
as a result of the peculiar oblique position of cell walls early in the embryogeny. The single
cotyledon is reduced to absorptive scutellum and additional structures like coleptile and
coleorrhiza are formed.
2 Endosperm Development
There are 3 types of endosperm development (a) nuclear - where the endosperm nucleus
undergoes several divisions prior to cell wall formation, e.g., wheat apple, squash, (b) cellular -in
which there is no free nuclear phase, and (c) helobial where the free nuclear division is preceded,
and is followed by cellularization as in some monocots. During the course of seed development,
reserve food materials are accumulated in the endosperm from the adjacent tissues.
In endospermic dicot seeds, endosperms are retained as a permanent storage tissue. In
non-endospermic dicot seeds, endosperm reserves are depleted and occluded by the developing
embryo. The reserves are then reorganized in the cotyledons, which in turn act as the source of
stored reserved food for embryo after germination. A part of the endosperm is depleted in cereals
during embryo maturation and this lies as a layer between the starchy endosperm and scutellum.
3 Seed-coat Development
Integument's of the ovule undergo marked reorganization and histological changes during
maturation to form seed coats. In bitegmic ovules (which have 2 integument's), the seed coat
may be derived from both the integument's or from the outer integument only; the inner
integument may disintegrate.

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4 Seed Structure and Functions
Seeds may be broadly classified as dicotyledons and monocotyledons, depending on the
number of cotyledons. Dicotyledons seeds may be either non-endospermic (exalbuminous) e.g.
chickpea, pea and bean or endospermic (albuminous) e.g., castorbean, fenugreek, etc.,
Monocotyledons seeds are mostly albuminous.
A typical non-endospermic dicot seed is made up of seed coat and embryo. The seed coat
consists of 2 layers that may be united or free, the outer layer, which is hard and made of thick
walled cells is called testa and the inner thin membranous layer is called tegument. The seed coat
is of considerable importance because it is the only protective barrier for the embryo from the
external environment.
1. The seed coat bears a scar called hilum, marking the point at which seed is attached
to stalk.
2. The funicle or the stalk forms a ridge called raphe along the margin of the seed.
3. At one end of the hilum, there is a small hole called micropyle. There is an outgrowth
below the hilum in leguminous seeds, which is called strophiole.
4. Certain other seeds (castorbean, nutmeg) have outgrowths called arials.
5. Arillar contents may important in attracting animals, which aid in seed dispersal.

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The embryo consists of embyonic axis and 2 fleshy cotyledons. The axis includes
embyonic root (radicle), hypocotyl to which 2 cotyledons are attached and plumule (shoot apex
with first true leaves). The cotyledons of non-endospermic e.g., pea are bulky and account for
over 90% of the mass of the seed.
Cotyledons of epigeal, non-endopermic species become leaf like and photosynthetic after
germination. In endospermic dicot seeds, the endosperm is bulky and stores food reserves. In
these cases, the cotyledons are small or haustorial in nature.
The nucleus of the ovary after fertilization becomes perisperm. The perisperm in the
majority of seeds fails to pass beyond an incipient stage of development but in a few cases this
tissue becomes the store for food reserves such as coffee.
Poaceae seeds are generally enclosed in one seeded fruit called caryopsis. The seed coat
is fused with fruit wall to form pericarp. The endosperm forms the main bulk of the grain and is
the tissue for food storage. It is separated from the embryo by a definite layer known as
epithelium.
The outer most layer of the endosperm is the aleurone layer, which unlike the rest of the
endosperm, is made up of living cells devoid of galactomannan reserves. This layer secretes
alpha-amylase and proteolytic enzymes which hydrolyse reserves of endosperm.
The embryo is very small and lies in a groove at one end of the endosperm. It consist of a
shield shaped cotyledon (Scutellum) and a short axis with plumule and radicle protected by
root cap.
The plumule as a whole is surrounded by coleptile, a protective sheath, and similarly the
radicle including the root cap is surrounded and protected by coleorrhiza.
Scutellum supplies growing embryo with food material absorbed from endosperm
through epithelium. The initial synthesis of alpha-amylase and certain proteolases also occurs in
scutellum.
4.2 Seed Growth and Maturation
Wheat and soybean representing monocots and dicots may illustrate the changes in the
pattern of accumulation of reserve materials at different stages of seed maturation.
In wheat, the dry weight of the seed increases rapidly in about 35 days after anthesis. The
water content of the grain is maximum between 14 and 21 days after anthesis, and then it
declines rapidly. The amounts of reducing sugar and sucrose are high between 7 and 14 days and
decline rapidly thereafter due to conversion to starch. Since in wheat, starch is the major reserve
material of the seed, the pattern of starch accumulation is similar to that of dry matter
accumulation.
The speed of germination is faster in wheat varieties that begin to lose water early during
seed development. The seed is said to have physiologically matured only when it attains
maximum dry weight, germinability and vigour. Normally the seed is harvested at field maturity,

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a stage when the moisture content is reduced to about 6-10 % in wheat. Field maturity is a crop
specific character.
A soybean seed attains maximum dry weight between 48 and 54 days after flowering. Oil
accumulation is less during 12-18 days after fertilization; maximum oil accumulates between 24
and 42 days after flowering, after which the rate decreases. The protein content in the seed is
maximum during 12-18 days after fertilization and decreases subsequently. The initial high
percentage of protein may be due to the high content of non-protein nitrogen, which decreases
with seed.
Components of Seed
Seed coat
It is the outer covering of seed and gives protection. It develops from the 2 integuments
of ovule. Outer layer of the seed coat which is smooth and rough is known as the testa and is
formed from the outer integument. The inner layer of the seed coat is called the tegmen and is
formed from inner integument.
Embryo
It is the mature ovule consisting of an embryonic plant together with a store of food, all
surrounded by a protective coat, which gives rise to a plant similar to that of its mother. It is a
miniature plant consists of plumule, radicle and cotyledon. The plumule and radical without the
cotyledon is known as primary axis.
Radicle
Rudimentary root of a plant compressed in the embryo is the radicle, which forms the
primary root of the young seedling. It is enclosed in a protective cover known as coleorhiza.
Plumule
It is the first terminal bud of the plant compressed in the embryo and it gives rise to the
first vegetative shoot of the plant. It is enclosed in a protective cover known as coleoptile.
Cotyledon
Cotyledons are the compressed seed leaves. A single cotyledon (Scutellum) is present in
monocots while two cotyledons are present in dicots, hence they are named as monocots and
dicots, respectively. In dicots they serve as storage tissue and are well developed, while
scutellum is a very tiny structure in monocots.
Endosperm
Endosperm develops from the endosperm nuclei which is formed by the two polar nuclei
and one sperm nuclei. It stores food for the developing embryo.
Appendages of seeds
Some seeds will have appentages that are attached to the seed coat. They vary with kind
of seed. The appendages sometimes help in dispersal of seeds or in identification of genotypes.
Some of the appendages are Awn, Hilum, Caruncle, Aril, Hair and Wings.
Awn : The thorn like projection at tip of the seeds. (eg) Paddy - The bract tip was elongated into
the awn.

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Hilum : It is the scar mostly white in colour present on the lateral side of the seed. It represents
attachment of the seed stalk to placenta of the fruit to mother plant (eg) Pulses.
Micropyle : The point where the integuments meet at the nucellar apex has been referred as
micropyle.
Chalaza : At region of integumentary origin and attachment opposite to micropyle is called
chalaza.
Rapha : The area between the micropyle and chalaza is the rapha. The rapha may be visible on
the seed coat of some species.
Caruncle: It is the white spongy outgrowth of the micropyle seen in some species (eg) Castor,
Tapioca.
Aril : It is the coloured flesh mass present on the outside of the seed (eg) Nutmeg.
Hairs : They are the minute thread like appendages present on the surface of the seed (eg)
Cotton.
Wings: It is the papery structure attached to the side of the seed coat either to a specific side of
the seed coat or to all sides (eg) Moringa.
SEED TECHNOLOGY -DEFINATION, OBJECTIVE AND ITS ROLEIN INCREASING
AGRICULTURAL PRODUCTION
SEED TECHNOLOGY
The role of seed technology is to protect the biological entity of seed and look after its
welfare.
COWAN, 1973: Defined Seed Technology as that “discipline of studies having to do with
seed production, maintenance, quality and preservation”.
FEISTRITZER, 1975: Seed technology as “the methods through which the genetic and
physical characteristics of seeds could be improved. It involves such activities as variety
development, evaluation and release, seed production, processing, storage and certification”
Seed technology includes the development of superior crop plant varieties, their
evaluation and release, seed production, processing, seed storage, seed testing, seed quality
control, seed certification, seed marketing, distribution and research on seed these aspects. Seed
production, seed handling based on modern botanical and agricultural sciences.
NATURE: It is a multidisciplinary science encompassing a range of disciplines such as:
1. Development of superior varieties
2. Evaluation
3. Release
4. Production
5. Processing
6. Storage
7. Testing
8. Certification/quality control
9. Storage
10. Marketing and distribution
11. Seed pathology
12. Seed entomology
13. Seed physiology
14. Seed ecology

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SCOPE
India is a vast country and bestowed with varied soils and has got different agro climatic
zones, enabling year round cultivation of crops. By and large, most seed crops are grown during
Kharif season. However most of the vegetable crops are produced in Rabi season and they posses
better quality seeds than the crop grown in kharif. Indian farmers can practice with multiple
cropping systems.
The farmers can opt for different crops like cereals, pulses oil seeds, vegetables, fibre
crops, etc., in all the three seasons viz., Kharif, Rabi and summer.
With the advancement of agriculture, the government of India felt that there is a need to
establish Seed Technology department in Agricultural Universities and ICAR institutes in India
after the recommendations and suggestions given by National Commission on Agriculture.
Accordingly, the Seed technology department was initiated throughout the country with the
following main objectives.
1. To teach seed technology course.
2. Research on seed production/processing/testing.
3. To strengthen the seed technology research.
4. To give training to those who are involved in seed production, processing, testing, etc.
Objectives /Goals of Seed technology
1. Rapid multiplication: To increase agricultural production.
2. Timely supply: New varieties must be available in time.
3. Assured high quality of seeds: Good vigour and viability.
4. Reasonable price: Cost of seed must be low to reach the average farmers.
Role of Seed Technology
Feistritzer (1975) outlined the following as roles of improved seed.
• A carrier of new technologies
• A basic tool of secured food supply
• The principal means to secure crop yields in less favorable production areas.
• A medium and rapid rehabilitation of agriculture in cases of natural disaster
Status
India is considered as a developed country as for as the seed sector is concerned. By
volume of seed we produce and distribute, we surpass many (western) nations in this trade. The
Indian seed industry at present consists of two national organizations (NSC and SFCI), 12 state
seed corporation about 150 large size private seed companies, 19 state seed certification agencies
and 86 notified seed testing labs.

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Area under seed production
India:
The estimated requirement by 2020 is 156.55 lakh quintals. The quantity of buffer stock
under seed security programmes in India has been fixed as follows
Certified - Self pollinated crops 5 per cent
- Hybrids 10 per cent
- Foundation seed 25 per cent
- Breeder seed 50 per cent
Karnataka:
35 lakh quintals of seeds required for Karnataka state. At present state is producing 26
field crop seeds viz., 6 cereals, 7 pulses; 9 oil seeds, 2 fibre crops and 2 commercial crops,
covering an area of 25,000 ha under certified seed production.
More than 50 per cent of area i.e., 11,000 ha is concentrated in Haveri, Dharwad,
Bellary, Raichur as they are best-suited zones for seed production. Presently 150 seed producers,
68 registered seed processing plant and 3 official seed-testing laboratories are operating in the
state.
Private sector: Accounts for 50 per cent of quality seed production in cereals and 90 per cent of
vegetable seed production is met out by the private sector.
Craze of hybrids/hybrid vegetables gaining popularity
In vegetable seed trade the craze is for F1 hybrids. At present less than 1 per cent of
vegetable are covered in F1 hybrids.
Hybrids in Karnataka
There are many number of hybrids are available as F1 in vegetable crop, viz., Tomato,
Capsicum, Brinjal, Watermelon, Okra, Chilli, Carrot, Radish, etc,.

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SEED DORMANCY
It is common observations that seeds of many plants species do not germinate when
freshly harvested even under favourable conditions. They need a period of rest/ storage before
they become capable of germination.
Inability of viable and mature seeds to resume growth immediately after harvest in an
environment normally favourable for the germination of the concerned plant species is known as
seed dormancy.
The period of rest after harvest that is necessary for germination is referred as after
ripening period. The period of dormancy varies from a few days to several years depending on
the plant species.
1. True dormancy/primary dormancy/innate dormancy: due to chemicals/ anatomical
features of seed.
2. Enforced dormancy/imposed dormancy/quiescence/ secondary dormancy: due to
unfavourable environmental conditions.
Ex: Exposure of dry barley seed to temperature of 50-900
C
Seven days storage of winter barley at high moisture content at 200
C
Placement of seed under water in dark condition for 3 days 20
C
Biological significance of Dormancy
Advantages:
1. Storage of seeds is prolonged, it is a survival mechanism
2. Seed can pass through adverse situation /conditions
3. Prevents the insitue germination i.e., vivipary
Disadvantages:
1. No uniform germination
2. Difficult to maintain plant population
3. Interferes in seed testing procedure
Nikolaeva (1969 and 1977) classified dormancy into three broad class are as below;
I. Exogenous Dormancy: Dormancy is due to some features of the seed located outside the
embryo
a. Impermeability of seed coat to water: due to seed coat structure, which is hard
enough to restrict the entry of moisture into the seeds, thereby preventing seed
germination. Ex: Malvaceae, Leguminoseae, Lilaceae
b. Impermeability of seed coat to gases; is related to the insufficient intake of oxygen
by seeds due to impermeability of seed structure enclosing embryo. Ex: Graminaceae,
fruit crops & forest trees
c. Mechanical resistances of seed coat: growth of embryo is checked due to extremely
hard seed/fruit structure such as seed coat, endosperm per carp etc., Ex: Acacia
species.
d. Inhibitors present in seed coat/endosperm: biochemical substances present in seed
coat or endosperm block the germination of embryo.

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Ex: Iris app- inhibitors present in the endosperm
Barley- Aflotoxin
Squash-Dichlobenil
Tomato-Feruline and Caffeie acid
All spp.- Coumarin
II. Endogenous dormancy: the reason for dormancy is present within the embryo
a. Incomplete embryo development: due to an incomplete development of the embryo.
In such cases, germination does not occur until the embryos develop to their normal
size. Ex: Palmaceae, Amgnoliaceae
b. Inhibitors present within the embryo: Dormancy arises from metabolic blocks
produced by biochemical substances called inhibitors present within the embryo. In
such cases germination can commence only when these inhibitors are leached out of
the embryo Ex: Xanthium, Fraximus
III. Combined Dormancy: dormancy is produced by a combination of two or more
factors which act in complementary fashion.
Ex: Fraximus
Methods of breaking dormancy
I. Natural breaking of dormancy: in nature dormancy terminates when embryo gets
suitable environment such as adequate moisture, aeration and temperature. The
impermeable seed coat present in many species became permeable due to the rupturing of
softening action of natural agents like micro organism, high or low temperature, humidity
fiber and abrasion due to wind or digestive tracts of birds and animals which feed on
these seeds. Ex: Rhizoctonia damages seed coat
I. Treatments to break Dormancy: the various treatments for overcoming dormancy
may be divided into the following three groups
1. Seed coat treatments: These treatments aim at making hard seed coat permeable
to water or gases either cracking or softening them. The process is usually
referred as scarification. These treatments are either physical or chemical in
nature.
a. Scarification:
i. Acid scarification: treating seeds with concentrated acids like sulphuric acid,
Hydrochloric acid etc.,
ii. Thermal scarification: the seeds are treated with different temperatures and
gases
iii. Mechanical scarification: The seed coat is damaged using mechanical
means. Viz.,
- rubbing seeds on sand paper or by using mechanical scarifier as in subabul
- Making small incision by piercing a needle as in bittergourd
- Removing of entire seed coat as in rubber
2. Embryo treatments:

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1. Stratification: the incubation of seeds at a suitable low temperature (Usually 0-
50
C) over a moist substratum before transferring them to a temperature optimum
for germination. Ex. Cherry (Prunus cerasus), Mustard and rape seeds
2. High temperature treatment: in some species, incubation at 40-500
C for few
hours to 1-5 days may be effective in overcoming dormancy. Ex. Rice seeds more
than 15% seed moisture treated in hot water of 400
C for 4-5 hours.
3. Chemical treatments: alternatively growth regulators or other chemicals may be
applied to induced germination growth regulators commonly used GA3 (100ppm),
kinetin (10-15ppm) and thio-urea (0.5-3%)
3. Miscellaneous approaches:
i. Exposing seeds to light
ii. Pressure treatment
iii. Infra red radiation treatment
iv. Magnetic treatment
SEED GERMINATION
In seed germination process, the seed’s role is that of reproductive unit; it is the thread of
life that assures the survival of all plant species. Furthermore, because of its role in stand
establishment, seed germination remains a key to modern agriculture.
Seed would normally germinates only after they have undergone a predefined period of
growth and development accumulating food reserves and finally becoming air dry.
Seed germination depends on a favourable combination of several external and internal
factors; in nature, seed must wait for this combination to occur for their germination.
Definition: Seed germination is the resumption of active growth of the embryo that
results in the rupture of the seed coat and the emergence of the young plant under favourable
conditions.
Types of germination:
1. Hypogeal germination: the cotyledons or storage organs do not emerges above the
soil surface; only plumule emerges above the ground. Ex: Most of the monocots and
pea
2. Epigeal Germination: The cotyledon or storage organs emerge above the soil
surface. Ex: Most of the dicots and pine
Phases of Seed Germination
1. Imbibiton: Rapid water uptake
2. Active Metabolism: Major metabolic events begin
3. Cell expansion: Seedling protrusion

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Fig. Phases of Seed Germination
Factors affecting seed germination;
1. Internal factor: Seed Maturity, Mechanical damages
2. External factors: a) Water b) Oxygen c)Temperature d)Light and e) Soil Factors
a. Water: Water is a basic requirement for germination. It is essential for enzyme
activation, breakdown, translocation and use of reserve storage materials.
b. Oxygen: atmospheric air is composed of 79.9 % Nitrogen, 20% oxygen and 0.03 %
carbon dioxide. Oxygen is required for germination of most of species. If CO2
concentration is higher than 0.03 % it retards germination. Respiration increases sharply
during seed germination. Since respiration is essentially an oxidative process, an
adequate supply of oxygen is a must.
c. Temperature: Seed germination is a complex process involving many individual
reactions and phases, each of which is affected by temperature. The effect on
germination can be expressed in terms of cordial temperature i.e., minimum, optimum
and maximum temperature. The optimum temperature for most of the seeds is between
15 to 30 0
C. maximum temperature is between 30 to 400
C. Some species will germinate
even at freezing point also ex. Alpine
d. Light: Some species required light for seed germination. Both light intensity (lux) and
light quality (colour and wavelength) influence seed germination
e. Soil factor: Soil structure, soil texture and soil temperature influences on seed
germination.
Volume

Time

Phase-‐I
Phase-‐II

Phase-‐III

Initiation
of

Visible

germination

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Seed Industry in India
Pre Independence:
In the early years of the twentieth century, as a result of the beginning of agricultural research at
agricultural colleges and research station, a few improved strains of cotton, wheat, groundnut
and sugarcane into existence.
The state depart of agriculture adopted two methods for the distribution of seeds on improved
varieties
1. Multiplication at one location and distributed over a larger area; so that the area under local
varieties could be replaced by improved varieties.
2. Seeds were distributed in small packets to a maximum number of farmers and it was
expected that farmers would multiply their own seed
However, second methods was tried in Bengal by distributing Jute and paddy, but this did
not increase coverage of new strains. Then concentrated on first method.
United province (UP) started producing seeds on the farms of landlords
United province in 1922- Established seed store in each Tehsil
1925: The royal commission on agriculture: examined introduction and spread of improved
varieties and progress of seed distribution
It made following suggestions
1. There should be separate department with agriculture to deal with seed distribution and
seed testing
2. The seed distribution enterprises should be self sustaining
3. Seed distribution should be organized through co-operatives, associations, seed
merchants, seed agents and agriculture department and any other agency which could be
considered suitable
4. Seed merchants should be given every encouragement.
Due to this GOT and state governments established several research institutes. Several
improves varieties were identified, However, the work of seed multiplication and distribution
did not keep pace with the research and development.
After RCA several similar analysis were made notable were:
John Russel (1937)
ICAR (1940)
Dr. Burns (1944)
Famine Enquiry Commission (1944)
Food Grains Policy Committee (1944). These reviews revealed that;
1. Crop botanists were involved in evaluation of improved varieties
2. The initial seed was multiplied on seed farms of agricultural department subsequent with
registered growers under close supervision of agricultural department.
3. Department of agriculture purchased seed from growers and distributed to farmers at
concessional price.

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1939: 2nd
world war- vegetable seed importing from abroad stopped
1945: Private seed companies established and started producing temperate vegetables at
Quetta and Kashmir valley
1946: The seeds men handling vegetable seeds organized themselves into an association.
The All India seed growers, merchants and nurserymen’s association with the objective of
ensuring the rapid development of the vegetable seed industry.
After Independence:
I Five year Plan (1951-56):
Greater emphasis was given by considering improved as basis for calculating the additional
production potential of food grains
1952; grow more food enquiry committee- noted non availability of pure seeds to farmers
1952; ICAR formulated Expert Standing Committee
As a result of these developments, the schemes for seed multiplication and distribution come
into existence in all the states of India.
Inspite of this, the progress was poor and seed programmes were confined primarily to seed
distribution after with subsidy
II Five year Plan (1956-61):
Improved seed was made the basis for ten percent additional food grain production. All
India co-ordinated maize programme was started. 4328 farms of 10 hectare established for
seed multiplication. Establishment of Seed testing labs and Co-operative stores.
1957: AICRP on Maize In ICAR collaborated with Rock Feller Foundation can be
considered as most significant turning point in Indian Agriculture.
1960: AICRP on sorghum and Bajra
1964: First hybrid sorghum was developed and released
1965: First hybrid bajra was developed and released
1959; Indo-American agricultural Team; to review food production problems given
suggestions to educate the farmers about use of quality seed. STL were established
1960; Review by programme evaluation organization. They identified problems associated
with seed multiplication and distribution.
1961: seed multiplication Team review. They gave recommendation on seed multiplication,
distribution and maintenance of quality
III Five year Plan (1961-66):
Serious efforts to overcome short coming of these seed programes
1961; Release of first hybrid maize; necessary to create separate organization for seed
production to exploit the full production potential of these hybrids.
1963; Central Seed Corporation (National Seed Corporation) the responsibilities were;
multiplication of newly released hybrids

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Development of seed industry in India
Establishment of quality control systems in India
1966: production of high yielding varieties. 9.2mha seed production area in 1968-69 was
increased to 25mha in 1973-74.
1965; Private seed industry named Indo-American Hybrid seeds was established
Annual Plan (1966- 69):
Seed legislation was forms
1968; Seed review team was established and they gave 101 recommendations for quality
seed production in the country.
IV Five year Plan (1969-74):
1969 Tarai Development Corporation Ltd. with the assistance of World Bank was started. Its
unique features were;
1. Involvement of G.B.Pant University of Agriculture and technology
2. Integrated development approach
3. Participation of seed growers as the share holders of the corporation
4. Compact area Approach
5. Strict quality control
6. Money back guarantee
7. Integrated approach for marketing of seeds
1970: Mini kit Programme was launched with paddy to spread new
1971; Indian Society of Seed Technologists (ISST) Provides opportunities for exchange
of ideas to persons engaged in seed production. ISST publishes Journal of Seed Research
and News letter Seed tech. News.
V Five year Plan (1974-79):
1971: National Commission of Agriculture was established and in 1976 they submitted a
report and suggested that;
1. Foreign collaboration of Seed Industry
2. Seed processing should made compulsory
3. Compulsory certification
4. Rigours enforcement of the seed act
5. GOT should be made an integral part of seed testing
1976: National seed programme was started with assistance of world bank.
Phase-I State Seed Corporation was established in 4 states Punjab, Haryana, Maharashtra
and Andra Pradeah
Phase II- State Seed Corporation in 5 states were started viz., Karnataka, Rajasthan,
Uttar Pradesh, Bihar and Orissa.

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IV Five year Plan (1980-85);
1983; Seed Control order was passed and included seed as an essential commodity
VII Five year Plan (1985-90);
Higher targets for quality seed production was fixed. Other objectives were
strengthening of Infra structure, establishment of National Seed Project
Phase III; State Seed Corporation in 4 states were established
Strengthening of seed technology research and training facilities were made
VIII Five year plan (1992-97);
Emphasis on hybrids seed production was made.
Review of progress in seed certification
The methods of seed certification
Indian minimum seed certification standards were published
Central Seed Certification Board for coordination
Review of Progress in Seed Testing
96 STLs were started with the potential of testing 4 lakhs samples per year
IX Five Year Plan (1998-2001)
The Seed Crop Insurance Scheme was started during 2000-01, with the objective to
motivate the farmers to take up the Seed Production Programme thereby increasing the
availability of certified seeds.
X Five year Plan (2002-2007):
• Maintenance of Seed Bank Scheme financial support has been provided to State Seed
Corporations (SSCs), National Seeds Corporation (NSC), State Farms Corporation of
India (SFCI) and State Seed Certification Agencies (SSCs).
• Department of Agriculture & Cooperation (DAC) has established Seed Bank at National
and State level in order to ensure that this basic input of agriculture is all the time
available to the farmers in all situations.
• Seed Plan Vision-2020: production of certified/quality seeds to meet at least 25% of the
total seed requirement by 2020
XI Five year Plan (2007-2012):
• National Food Security Mission (2007)
• Rashtriya Krishi Vikas Yojna (2007)

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GENERAL PRINCIPLES OF SEED PRODUCTION
Production of good quality seed is an exacting task requires high technical skills and
heavy financial investments. During seed production strict attention must be given to maintain
genetic purity and exploit its potentiality in next generation. In other words, seed production
must be carried out under standardized and well organized condition.
GENETIC PRINCIPLES
Causes for Deterioration of Genetic Purity
The genetic purity of a variety or trueness to its type deteriorates due to several factors during
the production cycles.
Kadam (1942) listed the following important factors responsible for deterioration of varieties.
1. Developmental variations
2. Mechanical mixtures
3. Mutations
4. Natural crossing
5. Minor genetic variations
6. Selected influence of pest and diseases
7. The technique of the plant breeder
1. Developmental Variations
When seed crops are grown under environments with differing soil, fertility, climate
photoperiods, or at different elevations for several consecutive generation's developmental
variations may set in as differential growth responses. It is therefor, preferred to grow the
varieties of crops in the areas of their natural adaptation to minimize developmental shifts.
2. Mechanical Mixtures
Mechanical mixtures, the most important reason for varietal deterioration, often take
place at the time of sowing if more than one variety is sown with the same seed drill, through
volunteer plants of the same crop in the seed field, or through different varieties grown in
adjacent fields. Two varieties growing next to each other field is usually mixed during harvesting
and threshing operations. The threshing equipment is often contaminated with seeds of other
varieties. Similarly, the gunny bags, seed bins and elevators are also often contaminate, adding to
the mechanical mixtures of varieties. Roguing the seed fields critically and using utmost care
during seed production and processing are necessary to avoid such mechanical contamination.
3. Mutations
Mutations do not seriously deteriorate varieties. It is often difficult to identify or detect
minor mutations occurring naturally. Mutants such as 'fatuoids' in oats or 'rabbit ear' in peas may
be removed by roguing from seed plots to purify the seeds.
4. Natural Crossing
Natural crossing can be an important source of varietal deterioration in sexually
propagated crops. The extent of contamination depends upon the magnitude of natural cross-
pollination. The deterioration sets in due to natural crossing with undesirable types, diseased
plants, or off types. In self-pollinated crops, natural crossing is not a serious source of

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contamination unless variety is male sterile and is grown in close proximity with other varieties.
The natural crossing, however, can be major source of contamination due to natural crossing.
Extent of genetic contamination in seed field due to natural crossing depends up on
1. The breeding system of the species
2. Isolation distance
3. Varietal mass
4. Pollinating agent.
The isolation of seed crops is the most important factor in avoiding contamination of the
cross-pollinated crops. The direction of prevailing winds, the number of insects present and their
activity, and mass of varieties are also important considerations is contamination by natural
crossing.
5. Minor Genetic Variations
Minor genetic variations can occur even in varieties appearing phenotypically uniform
and homogenous when released. The variations may lost during later production cycles owing to
selective elimination by the nature. The yield trials of lines propagated from plants of breeder's
seed to maintain the purity of self-pollinated crop varieties can overcome these minor variations.
Due care during the maintenance of nucleus and breeder's seed of cross-pollinated varieties of
crop is necessary.
6. Selected Influence of Pest and Diseases
New crop varieties often are susceptible to newer races of pests and diseases caused by
obligate parasites and thus selectively influence deterioration. The vegetatively propagated stock
also can deteriorate quickly if infected by virus, fungi or bacteria. Seed production under strict
disease free conditions is therefore essential.
7. The Techniques of the Plant Breeder
Serious instabilities may occur in varieties owing to cytogenetic irregularities in the form
of improper assessments in the release of new varieties. Premature release of varieties, still
segregating for resistance and susceptibility to diseases or other factors can cause significant
deterioration of varieties. This failure can be attributed to the variety-testing programme.
In addition to these factors, other heritable variations due to recombination's and
polyploidization may also take place in varieties during seed production, which can be avoided
by periodical selection during maintenance of the seed stock.
GENETIC PURITY MAINTENANCE
Hartmann and Kester (1968) & Agarwal (1980) described steps to maintain the genetic purity of
variety during seed production.
The following measures have been suggested to safeguard the genetic purity
1. Adoption of Crop: Growing crops only in areas of their adaptation to avoid genetic shifts.
2. Approved Class of Seeds: Use of only approved class of seed in seed multiplication and
adopt generation system.
3. Preceding Crop Requirement: Inspection and approval of seed plots prior to planting

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3. Isolation: Isolation of seed crops from various sources of contamination by natural crossing or
mechanical mixtures.
4. Roguing: Roguing of off types differing in characteristics from those of the seed variety.
5. Field Inspection: Qualified and experienced personnel of seed certification agency should
inspect seed crops at all appropriate stages of growth and verify seed lots or purity and
quality.
6. GOT: Periodic testing of varieties for genetic purity
AGRONOMIC PRINCIPLES
Standardized seed production, besides genetic principles, involves the application of the
following agronomic principles to preserve good seed quality and abundant seed yields.
1. Selection of suitable Agro-climatic region
Ø The seed crops have to be grown only in areas well adapted to the photoperiodic and
temperature conditions prevailing.
Ø Region of moderate rainfall and humidity are much more suited to seed production than
regions of high rainfall and humidity.
Ø In general, regions with extreme summer heat and very cold winters should also be
avoided for seed production unless particular crops are especially adapted to grow and
product under these conditions.
2. Selection of seed plot
Ø Seed production plot should have good texture and fertility.
Ø Should be free from volunteer plants weeds and other crop plants.
Ø Soil should be free from soil borne diseases and insect pests.
Ø The previous crops should not be same crop.
Ø The plot should get adequate isolation distance.
3. Isolation of seed crops
Ø The seed crop must be isolated from other nearby fields from the same crop
or any contaminating crop as per certification standards.
Ø Time isolation could also be used in some crops. This is a must to meet the
standards for genetic purity of seeds.
Ø Isolation of seed production of different varieties is also necessary to avoid
mechanical contamination.
4. Preparation of land:
Ø The land must be prepared well.
Ø Good land preparation helps in improved & uniform germination resulted in good stand
establishment.
5. Selection of variety:
Ø Variety should be adopted to agro-climatic condition
Ø Variety should be high yielder

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Ø Variety should posses other desirable characters like disease resistance, earliness, grain
quality etc
6. Selection of Seed:
Ø Seed purity: The seed used for raising a seed crop should be of known purity,
appropriate class and invariably obtained from authorized official agency.
7. Seed Treatment:
Ø If the seed is not treated already, it should be treated with appropriate
fungicides/insecticide prior to sowing.
8. Time of sowing:
Ø Should be sown at their normal planting time
9. Seed rate:
Ø Lower seed rate than usual to facilitate rogunig operation/seed inspection.
10. Method/depth of sowing:
Ø Invariably sown in rows at right depth.
11. Rouging
Ø To rouge plants (off types, pollen shedders, diseased plants, etc.,) at the earliest possible
but before flowering
Ø The number of rouging varies with the crop, purity of the source seed and the stage of the
multiplication of the seed crops.
Ø Rouging in most of the field crops may be done at - Vegetative, Pre-flowering, Flowering
and Maturity stages
12. Supplementary pollination
Ø In cross-pollinated crops supplementing the natural pollination is very much essential to
increase the seed yield.
Ø Provision of honeybees, hand pollination, floral mechanism, and rope pulling are some of
the techniques used in crosspollinated crops to increase the seed set and there by seed
yield.
13. Weed Control:
Ø Compete with seed crop and reduces seed yield and quality
Ø Presence of weed seeds at the time of harvest leads to mixing of weed seeds with crops
seeds and difficult to separate during seed processing
Ø Harbors pests and diseases
14. Disease and Insect management:
Ø Reduces seed yield and quality
Ø Infection of seeds with spores
15. Nutrition:
Ø Important role for proper development of plant and seeds
Ø N-Good healthy growth P-Fruiting and seed development K- flowering and seed
development
Ø Proper nutrition to achieve synchronization

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16. Irrigation:
Ø Required for translocation of all the nutrients
Ø Seed production areas should be dry regions with assured irrigation
17. Harvesting of seed crops
Ø Time and method of harvesting are important.
Ø Harvest when the seed is fully matured (Moisture content less than 20%)
Ø Early or late harvesting affect seed quality.
Ø Every effort should be made to avoid chance of mechanical mixing, mechanical injury to
seeds during harvesting, threshing, cleaning drying and packing.
18. Drying of seeds
Ø In order to preserve seed viability and vigour, it necessary to dry seeds to safe moisture
content levels as early as possible without heaping wet seed pods.
19. Storage of Raw Seeds
After sun drying, the seed should be filled in clean bags.
Ø The bags should be dipped in 2 % Melathion, dried and cleaned before they are filled.
Ø Mark the bag with name of variety and other details.
Ø The bags should be stacked on wood pallets but not directly on the floors.
Ø The height of the stack should not be more than 3 to 4 m for cereals, 2.5 to 3 m for other
crops.
Ø The godowns should be dry, cool and clean and spray with Melathion and later fumigate
as and when necessary.
SEED MULTIPLICATION RATIO
It is nothing but the number of seeds to be produced from a single seed when it is sown and
harvested. According to expert group on seeds (1989), the seed multiplication ratio for different
crops are as follows.
CROP SEED MULTIPLICATION RATIO
Wheat 1:20
Paddy 1:80(Variety)
1:100 (Hybrids)
Maize 1:100( Hybrids)
1:80 (Varieties)
Sorghum 1:100
Bajra 1:200
Ragi 1:80
Gram 1:10
lack gram 1:40
Green gram 1:40
Cowpea 1:40
Horse gram 1:40

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Moth bean 1:40
Red gram 1:100
Colecrops 1:433
Potato 1:4
Ground nut 1:8
Mustard and rape 1:100
Soy bean 1:16
Sunflower 1:50
Sesame 1:250
Safflower and castor 1:60
Linseed 1:50
Cotton 1:50
Jute 1:100
Mestha 1:40
Sun hemp 1:30
Berseem 1:10
Crops Seed Replacement Rate
SRR: Seed Replacement Rate is the percentage of area sown out of total area of crop planted in
the season by using certified/quality seeds other than the farm saved seed.
Crop SRR (%) Crop SRR (%)
Paddy 29 Cowpea 20
Jowar 23 Fieldgreen 8
Ragi 27 Bengalgram 21
Maize 30 Groundnut 13
Bajra 26 Sesamum 13
Wheat 19 Sunflower 23
Redgram 23 Soyabean 16
Horsegram 7 Safflower 17
Greengram 20 Castor 13
Blackgram 20 Cotton 15

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GENERATION SYSTEM OF SEED MULTIPLICATION
Generation system of seed multiplication is nothing but the production of a particular
class of seed from specific class of seed up to certified seed stage. The choice of a proper seed
multiplication model is the key to further success of a seed programme. This basically depends
upon,
a. The rate of genetic deterioration
b. Seed multiplication ratio and
c. Total seed demand (Seed replacement rate)
Based on these factors different seed multiplication models may be derived for each crop
and the 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. In view of the basic factors, the chain
of seed multiplication models could be.,
a. THREE - Generation model - Breeder seed - Foundation seed - Certified seed
b. FOUR - Generation model- Breeder seed - Foundation seed (I)- Foundation seed (II) -
Certified seed
c. FIVE - Generation model Breeder seed - Foundation seed (I)- Foundation seed (II) -
Certified seed (I) - Certified seed (II)
The chain of these models has been easily explained in the diagram. For most of the often
cross pollinated and cross pollinated crops 3 & 4 generation models is usually suggested for seed
multiplication .e.g. Castor, Red gram, Jute, Green gram, Rape seed, Mustard ,Sesame ,
Sunflower & most of the vegetable crops.

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Opel Green

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Classes of seed
The four generally recognized classes of seeds are: Breeder's seed, foundation seed,
registered seed and certified seed.
a) Nuclus seed: The initial hand full of seeds obtained from selected individual plants of a
particular variety, for the purpose of purifying and maintain that variety, by originating plant
breeder.
b) Breeder's seed: Progeny of Nucleus seeds, its production is directly controlled by the
originating or the sponsoring breeder or institution, providing for the initial and recurring
increase of foundation seed.
b) Foundation seed: The Progeny of breeders or foundation seed handled to maintain specific
genetic purity and identity. This seed is the source of all other certified seed classes.
d) Certified seed: The progeny of foundation or certified seed that is handled so as to maintain
satisfactorily genetic identity and purity and that has been approved and certified by the
certifying agency.
DIFFERENCES BETWEEN CERTIFIED SEED AND TRUTH FUL SEED
Certified seed Truthful labelled seed
Certification is voluntary Truthful labelling is compulsory for
notified kind of varieties
Applicable to notified kinds only Applicable to both notified and released
varieties
It should satisfy minimum field and seed standards Tested for physical purity and
germination
Seed certification officer, seed inspectors can take
samples for inspection
Seed inspectors alone can take samples
for checking
MALE STERILITY
The first documentation of male sterility came in Joseph Gottlieb Kölreuter observed
anther abortion within species and specific hybrids. Cytoplasmic male sterility has now been
identified in over 150 plant species. It is more prevalent than female sterility, either because the
male sporophyte and gametophyte are less protected from the environment than the ovule and
embryo sac, or because it results from natural selection on mitochondrial genes which are
maternally inherited and are thus not concerned with pollen production. Male sterility is easy to
detect because a large number of pollen grains are produced and are easily studied. Male sterility
is assayed through staining techniques (carmine, lactophenol or iodine); while detection of
female sterility is detectable by the absence of seeds. Male sterility has propagation potential in
nature since it can still set seed and is important for crop breeding, while female sterility does
not. Male sterility can be aroused spontaneously via mutations in nuclear and/or cytoplasmic
genes.
Male sterility can be either cytoplasmic or cytoplasmic-genetic. Cytoplasmic male
sterility (CMS) is caused by the extra nuclear genome (mitochondria or chloroplast) and shows

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maternal inheritance. Manifestation of male sterility in CMS may be either entirely controlled by
cytoplasmic factors or by the interaction between cytoplasmic and nuclear factors.
Genetic Male sterility
Ø Also known as nuclear male sterility as this type of male sterility is controlled by nuclear
geans.
Ø The expression of gene is not influenced by cytoplasmic genes.
Ø Inheritence is in Mendalien pattern.
Ø Majority of times sterility is controlled by recessive geans.
Cytoplasmic male sterility
Ø Cytoplasmic male sterility, as the name indicates, is under extra nuclear genetic control.
Ø They show non-Mendelian inheritance and are under the regulation of cytoplasmic factors.
Ø In this type, male sterility is inherited maternally.
Ø In general there are two types of cytoplasm: N (normal) and the aberrant S (sterile)
cytoplasms.
Cytoplasmic Genetic-male sterility
The male sterility system is the result of interaction between malesterility inducing cytoplasm
and nuclear fertility restorer genes.

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SEED CERTIFICATION
Seed certification
It is a legally sanctioned system for quality control and seed multiplication and
production. It involves field inspection, pre and post control tests and seed quality tests.
Objective of seed certification
To maintain and make available to the farmers, high quality seeds and propagating
materials of notified kind and varieties. The seeds are so grown as to ensure genetic identity and
genetic purity.
Eligibility for certification of crop varieties
Seed of only those varieties which are notified under section 5 of the seeds Act, 1966
shall be eligible for certification.
Breeder seed is exempted from certification. Foundation and certified class seeds come
under certification. Breeder seed is produced by the plant breeder and seed technologist which is
inspected by a monitoring team consisting of the breeder, representative of seed certification
agency (Deputy Director of Agriculture), representative of State Dept of Agriculture,
representative of National Seed Corporation (NSC, Deputy Manger), representative of State Seed
Corporation and nominee of crop co-ordinator (S-11). The crops shall be inspected at appropriate
stage.
Concept of Seed Certification
Concept of seed certification was originated in Sweden during twentieth century by
visiting agronomist and plant breeder to the progressive farmers, who took seeds from them,
primarily with the objective of educating them on how to avoid contamination. This initiated
field inspection process.
Seed Certification Agency
Principles for forming seed cetification agency:
1. It should not involve in seed production and marketing
2. It should have autonomy
3. Seed certification procedure adopted should be uniform throughout the country
4. It should closely associated with technical institutes
5. It should operate on a no profit and no loss basis
6. It should have adequate technical staff and facilities for timely inpection of seed fields
7. It should serve the interests of seed producers and buyers
PHASES OF SEED CERTIFICATION
1. Receipt and scrutiny of application
2. Verification of seed source
3. Field inspection
4. Post harvest supervision of seed crops
5. Seed sampling and testing
6. Labelling, tagging, sealing and grant of certificate.

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I. RECEIPT AND SCRUTINY OF APPLICATION
a. Application for registration
Any person, who wants to produce certified seed shall register his name with the
concerned Assistant Director of seed certification by remitting prescribed fee per crop, per
season. There are 3 seasons under certification viz., kharif (June - September), rabi (October -
January) and summer (February - May).
b. Sowing report (Application for the registration of seed farm)
The seed producer who wants to produce certified seeds shall apply to the Assistant
Director of Seed Certification in the prescribed sowing report form in quadruplicate with
prescribed certification fees along with other documents such as tags to establish the seed source.
Separate sowing reports are required for different crop varieties, different classes,
different stages and if the seed farm fields are separated by more than 50 meters. Separate
sowing reports are also required if sowing or planting dates differ by more than 7 days and if the
seed farm area exceeds 25 acres. The sowing report shall reach concerned Assistant Director of
Agriculture Seed Certification within 35 days from the date of sowing or 15 days before
flowering whichever is earlier.
In the case of transplanted crops the sowing report shall be sent 15 days before
flowering. The producer shall clearly indicate on the reverse of sowing report, the exact location
of the seed farm in a rough sketch with direction, distances marked from a permanent mark like
mile stone, building bridge, road, name of the farm if any, crops grown on all four sides of the
seed farm etc., to facilitate easy identification of the seed farm by the seed certification officer.
The Assistant Director, Seed Certification on receipt of the sowing report, scrutinises and
register the seed farm by giving a Seed Certification number for each sowing report. Then he
will send one copy of the sowing report to the Seed Certification officer, on to the Deputy
Director of Seed Certification and the third to the producer after retaining the fourth copy.
2. VERFICATION OF SEED SOURCE
During his first inspection of seed farm the Seed Certification officer will verify whether
the seed used to raise the seed crop is from an approved source.

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3. FIELD INSPECTION
OBJECTIVE
The objective in conducting field inspection is to verify the factors which can cause
irreversible damage to the genetic purity or seed health.
INSPECTION AUTHROITY
The seed certification officer authorized by the registering authority shall attend to field
inspections.
CROP STAGES FOR INSPECTION
The number of field inspections and the stages of crop growth at which the field
inspections should be conducted vary from crop to crop. It depends upon duration and nature of
pollination of the seed crop.
If the crop is grown for hybrid seed production, the number of field inspections during
the flowering stage should be more than one in the case of self-pollinated / cross / often cross
pollinated varieties.
In hybrid seed production and variety seed production of cross pollinated crops the
inspection during flowering should be made without any prior notice of the seed grower to judge
the quality of operation undertaken by him to maintain the genetic purity of the crop. But in the
case of self-pollinated crop the seed grower may be informed about the date of inspection.
In the former case if prior notice is given to the seed grower, it may not be possible to
detect the damage by the contaminants whereas in the latter case prior notice will lead to
improvement of the quality of the seed production work and thus the quality of seed.
The key points to be observed at each stage of inspection
Stage of crop
Key points to be observed at inspection
Stage of crop Key points to be observed at inspection
I. Pre flowering stage
(Vegetative Stage)
a. Verification of seed source
b. Confirmation of acreage given in the report.
c. Proceeding crop requirement
d. Planting ratio
e. Border rows
f. Isolation distance
g. Guide the grower in identification of offtypes, pollen
shedder, diseased plants, shedding tassels etc.,
II. Flowering Stages
(May be II and III inspections
when 50% of plants begin to
flower).
a. Confirm the observation of plants inspection were correct.
b. Confirm whether grower had continued thorough rouging,
after the previous inspection.
c. Verify the removal and occurrence of offtypes, pollen
shedders, shedding tassels, objectionable weed plants and
diseased plants.

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III. Inspection during post
flowering and pre-
harvesting stage.
a. Confirm the correctness of observations, made in earlier
inspections.
b. Guide the grower on rouging, based on pods, earhead, seed
and chaff characters such as colour, shape and size.
c. Explain to the grower when and how to harvest the crop and
process.
IV. Inspection during
harvest
(This is the last inspection
conducted on a seed crop).
a. Verify that male parent rows have been harvested separately.
b. Ensure complete removal of offtypes, other crops, weeds and
diseased plants etc.,
c. Seal properly by the certification agency of the threshed
produce after initial cleaning and drying.
d. Instruct the seed growers for sage storage and transportation.

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Bangalore-‐65
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Field counts
The purpose of field inspection is to find out field standards of various factors in the seed
farm. It is impossible to examine all the plants in the seed farm. Hence, to assess the field
standards of various random counting is followed.
Points to be observed before counting
1. All plants falling in each count must be examined for each factor
2. In hybrid seed field the prescribed number of the field counts should be taken in each parent
separately.
Number of counts to be taken
The number of counts taken and the method employed in taking counts vary from crop to
crop. It is necessary to take minimum of 5 counts upto 5 acres and an additional count for every
5 acres or part of as given below.
Area of the field (in acres)
Double count
In any inspection. if the first set of counts shows that the seed crop does not confirm to
the prescribed standard for any factor, a second set of counts should be taken for the factor.
However, when the first set of counts shows a factor more than twice the maximum permitted, it
is not necessary to take a second count.
On completion of double count assess the average for the two counts. It should not
exceed the minimum permissible limit.
Number of plants for a count
Sources of contamination or factors to be observed

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The contaminants are
1. Physical contaminants
2. Genetical contaminants
Physical contaminants are inseparable other crop plants, objectionable weed plants and
diseased plants. Genetical contaminants consists off-types, pollen shedders and shedding tassels.
a. Off type
Plant that differs in morphological characters from the rest of the population of a crop
variety.
Off type may belong to same species or different species of a given variety. Plants of a
different variety are also included under off types. Volunteer plants and mutants are also off
types.
b. Volunteer plant
Volunteer plants are the plants of the same kind growing naturally from seed that remains
in the fields from a previous crop.
c. Pollen shedders
In hybrid seed production involving male sterility, the plants of 'B' line present in 'A' line
are called pollen shedders.
Some times 'A' line tends to exhibit symptoms of fertile anthers in the ear heads of either
on the main tiller or side tiller and these are called partials. These partials are also counted as
pollen shedders.
d. Shedding tassels
These plants which shed or shedding pollen in female parent rows. When 5 cm or more
of the entire spike, which shed or shedding are counted.
e. Inseparable crop plants
These are plants or different crops which have seed similar to seed crop
f. Objectionable weed plants
These are weeds
1. Whose seeds are difficult to be separated once mixed
2. Which are poisonous
3. Which have smothering effect on the main crop
4. Which are difficult to eradicate once established
5. Difficult to separate the seeds. These seeds cause mechanical admixtures
g. Designated diseases
The diseases which may reduce the yield and quality of seeds are termed as designated diseases.
Inspection report
The seed certification officer after taking field counts and comparing them with the
minimum field standards, the observations made on the seed farm field should be reported in the
prescribed proforma to
1. Deputy Director of Agriculture (Seed Certification)
2. To the Seed Producer

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3. Assistant Director of Agriculture (Seed Certification) and
4. Fourth copy retained with seed certification officer
Assessment of seed crop yield
It is necessary to avoid malpractice's at the final stage during harvest operation. The seed
certification officer is expected to fix the approximate seed yield.
Liable For Rejection Report (L.F.R)
If the seed crop fails to meet with any one factor as per the standards, Liable for
Rejection report is prepared and the signature of the producer is obtained and sent to Deputy
Director of Agriculture Seed Certification within 24 hours.
Re-inspection
For the factors which can be removed without hampering the seed quality, the producer
can apply for re-inspection to the concerned Deputy Director of Agriculture Seed Certification
within 7 days from the date of first inspection order. For reinspection half of the inspection
charge is collected.
Post harvest supervision of seed crop
The post harvest inspection of a seed crop covers the operations carried out at the
threshing floor, transport of the raw seed produce to the processing plant, precleaning, drying,
cleaning, grading, seed treatment, bagging and post processing storage of the seed lot.
Pre-requisites for processing
1. Processing report should accompany the seed lot
4. Seed should be processed only in approved processing unit.
2. ODV test for paddy should be done at the time of sealing and issue of processing report or
before processing. If the result exceeds 1% of the produce may be rejected.
3. It should be correlated with the estimated yield
5. Field run seed should be brought to the processing unit within the 3 months from the date of
final inspection. Processing and sampling should be done within 2 months in oil seed crops and 4
months for other crops from the date of receipt in the processing unit. In cotton the kapas from
the passed lot should be moved to the ginning factory within 5 days from the date of issue of
processing report. The ginning should be done within 3 months from the date of final harvest
inspection report. Ginned seeds should be moved to seed processing unit within in 5 days of
ginning. Inspection and sampling should be done within 3 months after ginning.
Intake of raw produce and lot identification
The seed certification officer in-charge of the seed processing plant may, after
verification of the above stated documents and total amount of seed accept the produce for
processing. After verification he should be issue a receipt to the seed grower. Each seed lot has
tobe allocated a separate lot number for identification.
Processing of seed lot
1. It is done to remove chaff, stones, stempieces, leaf parts, soil particles etc from the raw seed
lot.

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2. Grading to bring out uniformity in the seed lot.
3. Seed treatment to protect it from storage pests and diseases.
Processing inspection
1. The processing should be done in the presence of concerned seed certification officer.
2. The recommended sieve size should be used for grading
3. While processing of paddy, the work of perfect processing have to be evaluated then and
there.
This is done by conducting a float test. Take 400 seeds from the processed seed and put in to a
tumbler of water. Count the floating paddy seeds. Maximum float admissible is 5%. If the float
seeds exceed the limit, adjust the air flow or feeding to perfect the processing.
4. In maize before shelling the cobs should be examined for off type and off coloured kernels.
Individual cobs should be examined with reference to its vareital characters. The cobs of off
types and off coloured kernels should be rejected.
5. Seed sorting in cotton.
The ginned seeds will be evaluated for its quality. A maximum of 3 % for the following factors
can be taken into accounts.
1. Immature seeds
2. Ill filled seeds
3. Broken seeds
4. Stained seeds and
5. Over fuzzy seeds
5. Seed sampling and testing
During packaging Seed Certification officer will draw samples according to ISTA
Procedure and send the sample to Assistant Director of Agriculture (See Certification) concerned
within a day of sampling. The ADASC will in turn send the sample to the Seed Testing
Laboratory within 3 days of receipt of the sample to testing seed standards viz., physical purity,
germination, moisture content and seed health as prescribed. The Seed Testing Officer will
communicate the result to the ADASC concerned within 20 days.
On receipt of the analytical report the ADASC will communicate the result to the
producer and Seed Certification officer.
6. Labelling, tagging, sealing and grant of certificate
After receiving the seed analytical report the Seed Certification officer will get the tag
from the ADASC and affixes labels (producer's label) and tags (blue for Certified Seed and
White for Foundation Seeds) to the containers and seals them to prevent tampering and grants
certificate fixing a validity period for 9 months. Tagging should be done within 60 days of
testing.
7. Resampling and reprocessing
When a seed lot does not meet the prescribed seed standards in initial test, on request of
the producer Seed Certification Officer may take resample.

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If the difference in germination analysed and required is within 10, then straight away
resampling can be done. If it is >10, reprocessing and resampling may be done.
The producer should request the Seed Certification Officer concerned in writing within
10 days from the receipt of the result. No charge is collected for resampling.
When a seed lot, fails even after free sampling reprocessing can be taken upon special
permission from Deputy Director Seed Certification. For such reprocessing a fee of Rs.20/- Q
and lab charges Rs.10/- Q is collected.

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Seed production in cereal crops
Seed Production Techniques in Rice (Oryzae sativa. L)
Paddy is the staple food of India botanically known as Oryzae sativa L. belongs to the
family Poaceae. It is an economic crop of India since most of the Indians are having rice based
food habits. It is also used as a raw material for cottage industries and infant food industry. The
straw is fed to cattle and oil extracted from bran is used for cooking and has got high medicinal
value.
Important cultural Practices that maintain different seed quality characters
Choice of field, Isolation, Parent seed selection, Roguing Genetic purity
Fertilizer, Spacing, Insect and Disease control, Harvesting Physiological Quality
Choice of field, Harvesting, Threshing, Processing Physical purity
Land/Proceeding crop requirement
ü It should be a fertile one.
ü Saline /alkaline problem soils should be avoided
ü Should have adequate irrigation facilities and drainage facilities
ü Previous crops should not be other paddy (for 6months) varieties
ü Clay loamy soils with pH around 6.5 are best suited
Isolation Requirement: Isolate seed field by at least 3 m
Source of Seed
Ø Must be from authenticated source (UAS’s/KSSC)
Ø Must be suitable generation class for further multiplication (Eg. BS/FS/CS)
Ø Must be checked by certification officer before sowing
Seed Rate
Bold Varieties: 25 Kgs
Medium/fine Varieties: 20-25 kg/ha
Season: Kharif: June-July (Up to Aug)
Summer: December-February
Seed Treatment
Ø Can grade using salt water (1.06 density) to separate choppy seeds
Ø Dress with fungicide @ 2g /kg. (Thiram/Capton/Carbandizim)
Ø If dormant soak the seed with 0.5 % KNO
3
for 16 h
Seed bed (Nursery) preparation
v Select the land which should be fertile & puddle for good tilth
v Sunken Nursery for easy operation (2 x 50m)
v 200 sq.m. Nursery is needed for planting
v Let the water stand in nursery to a tune of 2-3 cm throughout the nursery period.
Seed Preparation
Ø Loosely pack the seed in jute (pervious container).
Ø Soak in water for 24 hours (Running H
2
O)

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Ø Incubate for 24 hours in dark
Ø At slight radicle emergence the seed in ready for sowing
Nursery Sowing
v Broadcast the germinated seed on the thin film of water carefully and uniformly
v After emergence irrigate and raise the level according to the seedling height
v Based on the growth if needed give some fertilizer (N and P)
Mainfield preparation
ü Put cultivator at dry condition
ü Harrow the soil to loosen the soil (fine tilth)
ü Flood the field with water
ü Puddle for 2-3 times using cage wheel
ü Apply P and K at last puddling
ü The bunds must be plastered well to have a check on weed growth and water control
Transplanting
v At the age 25-30 days pull out the seedlings (10-15 cm height) from the nursery bed
and transfer to mainfield.
v Use 25 x 20cm spacing for planting soil
v Planting depth may be 3-5 cm.
v Transplant the seedlings at the rate of 1-2 seedlings / hill
v On growing season – standing water should be 5 cm (always).
Fertilizer
v Apply full dose of P and K at last puddling / ploughing
v Apply N in 2 split doses 1
st
at tillering phase, 2
nd
at Panicle initiation stage.
v Dosage (vary with area) (Eg.: 120:60:60 kg/ha)
v Better if based on soil analysis.
Weeding
Ø Use pre-emergence weedicide to control weeds at early stage.
Ø Hand weed the crop at 20 days after transplanting and before panicle initiation stage
Ø Common weeds : Cyprus spp., Echinocloa sp.
Insects and Diseases
ü Apply insecticides and fungicides as recommended to the area.
ü Common Diseases are : Rust, Bunt, leaf spot, Rust.
ü Common insects are : Brown plant hopper, leaf roller etc.
Roguing
Ø Is important to maintain for maintenance of genetic purity
Ø Remove all off types (deviants of the variety) and Rogues (variant of the crop)
Ø “Remove when doubt” – rule.
Roguing characters for paddy
Ø General appearance (Tall, medium, short)
Ø Leaf colour (Dark green, Pale green).

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Ø Leaf shape (Broad, narrow).
Ø Panicle shape (open, close).
Ø Awns (appendages) (Awned, Awnless)
Ø Glume colour (Pink, green)
Ø Boot leaf (Rectangle, erect)
Ø Tillering (Heavy, Medium)
Ø Maturity (Late, early – Uniform)
Ø Grain type (long, slender, short, bold).
Ø Hull colour (Dark yellow, light).
Ø Kernal colour (Red, white)
Field Inspection
- Done by the Seed Certification Officer on registration for certification.
- Done at
1. Tillering phase
2. Heading phase
3. Before harvest
Field condition required at field inspection
Ø The field should be free of rogues / off types at the time of inspection
Ø If the percent of rogues is above the certification standards then the field is rejected
(e.g. 0.2% Max. limit in India).
Ø Wild rice should not be there in the field
Ø The objectionable weed also should be below the maximum limit (e.g.: 0.02% India)
for getting the crop certified.
Ø Look for: At the times of inspection the characters of variety grown will be checked
with the description of the varieties.
Physiological maturity
v Earheads turn golden yellow color and will droop. (Lodging should be avoided)
v When 85% are so crop is ready for harvest
v The moisture content will be about 18-20%
Crop duration
- 90-160 days highly depends on varieties specified (eg. : THANU : 130 days)
Harvesting
- At 85% maturity, drain the field and allow drying (field) for easy harvest.
Manual
Ø Harvest with straw with sickle (manual)
Ø Bundle the produce.
Ø Transfer to thrashing floor for thrashing and drying
Mechanical
ü Machine should be cleaned thoroughly to avoid mechanical mixtures
ü Machin harvesting should be done at moisture content of 18-20%.

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Threshing
Threshing must be done carefully in order to reduce the risks of damaging the seeds
and to avoid mechanical mixtures.
v M/C should be 18-23%.
v Clean the threshing floor, equipments, containers to avoid genetic and physical mixture.
v Produce can be threshed using tractor (with rubber tiers with deep grooves) or
mechanical thresher.
v Winnow immediately after threshing
Drying
When seeds has just been harvested, it is still moist and therefore dried, since well-dried
seeds keeps longer, insect attack and fungus diseases are reduced.
Ø Spread the seed in the open air for few days.
Ø Avoid drying seed under hot sun.
Ø Dry the seed (harvested/threshed producer) under sun to bring the m/c to 12-14%
Ø Frequent stirring of material is necessary while drying.
Ø Can also mechanically dried using driers (avoid high temperature to high moist seed)
Seed processing
ü Use air screen cleaner with oblong sieve
ü At processing the certification officer will check and will take sample and will sent it
the STL for seed standard verification.
Expected yield
3 – 5 tons/ha (depending upon the area and variety)
Field standards for certification
Class of Seed C.S. F.S.
Off types (max.) 0.20 0.050
Plants affected by seed borne
disease
Nil Nil
Seed Standards :
Pure seed (min.) 98 98
Inert matter (max.) 2 2
Other crop seed (max.) 20 No/kg 10 No/kg
Total weed seed (max.) 20 No/kg 10 No/kg
Other distinct variety 20 No/kg 10 No/kg
Objectionable weed seed
(max.)
5 No/kg 2 No/kg
Germination % (min.) 80 % 80%
Moisture content (%)

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(i) Ordinary container 13% 13%
(ii) Vapour proof container 8% 8%
Huskless grain (max.) 2% by number 2% by number
Hybrid seed production
Hybrids and their parentage
Hybrid Female Male
KRH-1 IR58025A IR 9761
KRH-2 IR58025A KMR-3
KRH-4 CRMS32A MSN36
Rice is a self-pollinated crop, where the extent of natural out-crossing ranges from 0.3 to
3.0%. The success of hybrid seed production however demands higher out-crossing rate to obtain
high seed yield. Therefore, hybrid rice seed production requires specialized techniques, which
need to be thoroughly understood before embarking upon this venture.
Hybrid seed production tool: CGMS
a. BS or FS: Maintenance of A, B and R lines
b. Certified seed production: hybrid seed production (A×R)
Choice of location:
As it is well known that rice hybrid seed production is a cumbersome practice, a viable seed
production requires specific location having fertile field with proper irrigation and drainage
system, sufficient sunshine during flowering, and no serious disease and insect problems.
Therefore, while choosing location for hybrid seed production above said requirements should be
considered.
Favourable climatic conditions:
• Overall daily mean temperature of 240– 30 ˚C
• Relative humidity ranging from 70 – 80 %
• The differences between day and night temperatures should not be more than 80–10 ˚C
(50-7 0C is optimum).
• Sufficient sunshine with moderate wind velocity (2-3m/sec).
• There should not be rains continuously for three days during the period of flowering.
• Yield will be adversely affected if overall daily mean temperature during flowering is
below 20 ˚C and above 35 ˚C
Isolation
Spatial isolation: Unwanted varietal contamination in hybrid seed production can be prevented
by maintaining at least 100 meter distance between hybrid seed production for certified and 200
m for foundation seed.
Time isolation: Wherever it is difficult to have space isolation, a time isolation of over 21 days
would also be effective. It means that the heading stage of the parental lines in hybrid seed

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production plot should be 21 days earlier or later than that of other varieties grown in the
vicinity.
Barrier isolation: In some places, the natural topographic features such as mountains, rivers,
forests etc. can serve as the most effective barrier. A crop barrier with maize, sugarcane and
Sesbania covering a distance of 30 m would also serve the purpose of isolation. Artificial barrier
with polythene sheets and seed nets of about 3 m height can also be used in case of small scale
seed production.
Nursery management and seed rate
• Prepare raised seedbeds (5-10 cm height) of 1m width of any convenient length.
• Provide drainage channels (30 cm) in between seedbeds to drain excess water.
• Sow pregerminated seed uniformly on the seedbed (@ of 1-2kg seed/20m2
)
• Use 15 kg of `A’ line seed and 5 kg of `R’ line seed to produce sufficient seedlings to
grow in one hectare each.
• Manage the seedbed properly for getting healthy and vigorous seedlings for transplanting.
Seeding and transplanting sequence
In case seed parent (A line) has 10 days longer growth duration than pollen parent (R line):
Seed/pollen parent Seeding sequence Seedling age for
transplanting (days)
A line 0 day 25
First R line 6th day 29
Second R line 10th day 25
Third R line 14th day 21
In case seed parent (A line) has 10 days shorter growth duration than pollen parent (R
line):
First R line 0 day 29
Second R line 4th day 25
A line 14th day 25
In case seed parent (A line) has same growth duration as pollen parent (R line):
First R line 0 day 29
Second R line and A line 4th day 25

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Transplanting
• In hybrid rice seed production, the seed parent and pollen parent are planted in a certain
row ratio at certain spacing
• To encourage out-crossing, the rows of male and female in the seed production plot
should be perpendicular to the prevailing wind direction expected at flowering time of the
parents.
• Planting ratio of 8:2 or 6:2 is preferred
• Spacing:
Male :male - 30 cm,
Male :female - 20 cm
Female: female -15 cm
Plant :plant – 15 cm
Fertilizer management: 10 t/ha FYM and 120:60:40 kg/ha NPK
Out-crossing encouragement:
Most of the male sterile lines based on WA cytoplasm have imperfect exsertion of panicle. As a
result, as much as 15-20% spikelets remain enclosed in the flag leaf and are not exposed for out
crossing. By adopting following methods, the exsertion of the panicles can be promoted to a
great extent.
Application of gibberellic acid (GA3): It is an efficient and effective plant growth regulator,
which stimulates the cell elongation, thus can be used to enhance panicle exsertion in CMS line.
Besides, GA3 has the following favorable effects:
• Increases the duration of floret opening
• Increases stigma exsertion and receptivity
• Promotes plant height
• Influences flowering and hence flowering in parental lines can be adjusted
• Widens the flag leaf angle
• Promotes exsertion and growth rate of secondary and tertiary tillers.
In hybrid seed production plots of rice, 8-10% panicle emergence stage is most appropriate for
first spraying (40%) and the remaining 60% of GA3 should be sprayed on the following day.
Flag leaf clipping: Normally the flag leaves are erect and longer than the panicles and they
come on the way of easy pollen dispersal thus affecting the out-crossing rate. The clipping of
flag leaf helps in free movement and wide dispersal of pollen grains to give higher seed
production. The flag leaves should be clipped when the main culms are in booting stage. Only
half or two-third portion of flag leaf should be removed. However, flag leaf cutting is not
advisable in the plots infested with diseases as this operation may spread the disease further.
Supplementary pollination: Rice is basically a self-pollinated crop and hence in order to
enhance the extent of out-crossing there is a need to go for supplementary pollination.
Supplementary pollination is a technique of shaking the pollen parent so that the pollen is shed
and effectively dispersed over the A line plants. Supplementary pollination can be done either by
rope pulling or by shaking the pollen parent with the help of two bamboo sticks. Timing and

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material,
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Vishwanath
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Asst.
Professor,
UAS,
GKVK,
Bangalore-‐65
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frequency of supplementary pollination is very important. The first supplementary pollination
should be done at peak anthesis time i.e. 8.30 a.m. to 10.30 a.m. when 30-40 % of the spikelets
are opened. This process is repeated 3–4 times during the day at an interval of 30 minutes.
Supplementary pollination has to be done for 7-10 days during the flowering period.
Field Inspection: A minimum of four inspections shall be made (1st
before flowering, 2nd
and 3rd
during flowering and 4th
during maturity)
Stages of rouging
Stages Off types Characters
Vegetative stage Based on plant characters like plant height, leaf color, leaf
size, leaf shape and pigmentation color on stem.
Flowering stage Differences in days of flowering, panical type and awenness,
any plant on a line row having complete panicle exertion with
yellow plumpy anthers ,flower color.
Free harvesting stage Based on grain color ,grain size any disease affected plants.
Harvesting: All R line rows are to be harvested first. The R line harvest is to be removed and
kept in a safe place separately. The left over R line panicles in the field should also be removed.
After R line harvesting, a final roguing in seed parent has to be done carefully, removing the
plants showing more than 70% seed setting. Then the seed parent plants are to be harvested.
Threshing: During threshing, the `A’ line parent and `R’ line parent harvests must be kept
separate from each other. The A and R lines should be threshed separately. Before starting
threshing, all the threshing equipment, threshing floor and tarpaulin to be thoroughly cleaned.
Grading:
Seed yield: 6-8 q ha-1
Seed production techniques in wheat (Triticum aestivum)

Wheat (Triticum aestivum) belongs to family Poaceae. It is staple food od many Indian
communities
Land/Proceeding crop requirement
ü It should be a fertile one.
ü Saline /alkaline problem soils should be avoided
ü Should have adequate irrigation facilities and drainage facilities
ü Previous crops should not be wheat
Isolation Requirement
ü Highly is mainly self pollinated crop and cross pollination varies from 0.1 to 4.0 per
cent.
ü Isolate seed field by at least 3 m
ü Fields of wheat, triticale and rye with infection of Loose smut (Ustilago tritici (Pers.)
Jens.) disease in excess of 0.10% and 0.50% in case of Foundation and Certified seed,
respectively the isolation distance will be 150 m respectively

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Professor,
UAS,
GKVK,
Bangalore-‐65
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Source of Seed
Ø Must be from authenticated source (UAS’s/KSSC)
Ø Must be suitable generation class for further multiplication (Eg. BS/FS/CS)
Ø Must be checked by certification officer before sowing
Seed Rate: 140-150Kg/ha
Season: Middle October to first week November
Seed Treatment: Dress with fungicide @ 2g /kg. (Thiram/Capton/Carbandizim)
Method of sowing
v Prepare the land to fine tilth
v Seeds are sown in rows of 20cm with help of seed drill or behinf plough the plough in
furrow
v Depth of sowing should not more than 5cm
Fertilizer
v Apply 7.5 tonns of FYM
v 50:75:50=N:P:K/ha
v Top dressing 30DAS
v Zinc 20Kg/ha
Igrrigation
Ø 8-10 days for sandy loam
Ø Once in 15 days for heavy soils
Weeding
Ø Post emergent weedicide to control weeds at early stage.
Ø Hand weed the crop at 30 days after transplanting and before panicle initiation stage
Ø Common weeds : Convolvulus arvensis, Lathrys spp and Vicia spp
Insects and Diseases
ü Common Diseases are : Rust, leaf blight and smut
ü Common insects are : Termite, stem borer, Stink bug, Aphid, Plant hopper and Root
grub
Roguing
Ø Remove all off types (deviants of the variety) and Rogues (variant of the crop)
Ø Remove inseparable crops plants like barley, oats, triticle and gram
Ø “Remove when doubt” – rule.
Roguing characters for wheat
Ø General appearance (Tall, medium, short)
Ø Leaf colour (Dark green, Pale green).
Ø Leaf shape (Broad, narrow).
Ø Awns (appendages) (Awned, Awnless)
Ø Boot leaf (Rectangle, erect)
Ø Tillering (Heavy, Medium)
Ø Maturity (Late, early – Uniform)

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UAS,
GKVK,
Bangalore-‐65
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Ø Kernal colour (Red, white)
rouguing should be done as and when required from the beginning upto last (Harvest)
Field Inspection
- Done by the Seed Certification Officer on registration for certification.
- Done at
1. Tillering phase
2. Before harvest
Physiological maturity
v Earheads turn golden yellow colour
v The moisture content will be about 18-20%
Harvesting and threshing soon after maturity
- Delay- pre harvest sprouting
- MC (%) should be 16%
Drying, cleaning and Bagging
- In north India harvesting at 9-10% MC
- To maintain good quality clean/process/treat and bag the seeds before monsoon
Yield: 30-40qtls/ha
Seed standards
Seed Standards :
Pure seed (min.) 98 98
Inert matter (max.) 2 2
Other crop seed (max.) 20 No/kg 10 No/kg
Total weed seed (max.) 20 No/kg 10 No/kg
Objectionable weed seed
(max.)
5 No/kg 2 No/kg
Germination % (min.) 85 % 85%
Moisture content (%)
(i) Ordinary container 12% 12%
(ii) Vapour proof container 8% 8%

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Vishwanath
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Asst.
Professor,
UAS,
GKVK,
Bangalore-‐65
Page
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Hybrid Seed Production in Maize (Zea mays)

Scientific name : Zea mays Family : Poaceae
Maize (Zea mays) is one of the most important cereal crop in the world grown over an area of
132 Mha with a production of 570m.t. It is the crop with the highest productivity.
Maize is serving as staple food for vulnerable segment of the population and it rank first in
importance as feed crop and also important source of raw material used in numerous industrial
materials.
Floral biology
• The monoecious corn plant has female flowers that develop on the side of the plant and
emerge from the leaf node.
• The inflorescence is unisexual and monoecious.
• Staminate inflorescence is terminal and known as tassel and pistillate is axillary and
called as cob
Anthesis and Pollination
ü Maize is an example for protandry.
ü Pollen shedding begins 1-3 days before the silks emerge from the cob.
ü It is estimated that a normal tassel produces 2,50,00,000 pollen grains.
ü Pollen is viable for 12-18 hours. Silk remains receptive for 8-10 days.
ü Anthesis continues up to 2 weeks
In maize, in addition to varieties and hybrids, composites and synthetics are also available.
Synthetics and composites seed production
Varieties: Vijay, Vikram, Amber, Sona, NAC-6002, NAC-6004 and shakthi
Climatic requirement
• Maize grown in wide range of environmental conditions
• About 85 % of total acreage under maize is grown during monsoon because of the fact
that crops stops growing if the night temperature falls below 15 ˚C
• Its needs bright sunny days for its accelerated photosynthetic activity and rapid growth of
plants
• Prolonged cloudy period is harmful to the crop
• Maize is cultivated during June – July, September- October and January - February
seasons
Land requirement: Loamy soil with high organic matter with neutral pH is the best for maize.
The land should meet preceding crop requirement
Isolation: Since maize is a cross pollinated crop, it is necessary to isolate seed field from maize
crops of any other variety. The seed field must be isolated at least by 400 meters for foundation
and 200 metres for certified class seed from seed of other varieties of maize.
Field preparation and sowing
ü Plough the field five to six times to get fine tilth.

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