SEED TESTING The main objective of seed testing ... - SeedNet India

SEED TESTING
The main objective of seed testing is to assess the actual planting value of the seed in
terms of its germination capacity besides determination of percentage composition of the
pure seeds, weed seeds, other crop species, extraneous matter and moisture content of the
submitted sample.
Seed testing procedures
Registration of seed samples: The submitted samples should be of the specified weight.
The accepted sample is registered for testing and is given a code number so as to maintain
the secrecy about its identity during testing. The details of the samples such as crop,
variety, class of seed, tests required etc. are entered in individual seed analysis cards.
Working sample of specified size is obtained from the submitted sample by using the seed
dividers.
Physical purity analysis: The purity analysis is done on a working sample of prescribed
weight drawn from the submitted sample. The working sample is separated into different
components like pure seed, other crop seed, weed seed and inert matter by physical
examination and the details are recorded in the individual analysis card. The composition of
different components is expressed either in percentage by weight or as numbers per
kilogram.
Germination testing: The pure seed fraction from the purity test is used for germination
analysis. A minimum of four hundred seeds in replications as per convenience are tested for
germination. The most important requirements for seed germination testing are substrata,
moisture, temperature and light.
Substrata
The substrate serves as a moisture reservoir and acts as a medium for the seeds to
germinate and the seedlings to grow. The commonly used substrates are paper and sand.
The standard Kraft paper (towel), filter paper and blotters are the widely used paper
substrates. Sterilized sand with a particle size between 0.045 mm to 0.85mm is used for
germination test.
Methods of using substrata
Top of paper (T.P): In this method seeds are placed directly on one or more layers of
moist filter or blotter papers in Petri dishes or plastic boxes which are in turn kept for
incubation. This method is used for small sized crop seeds like ragi, jute, onion, tomato etc.
Between paper (B.P.): Seeds are placed in between two moist germination papers and
rolled together to look like a rolled towel. The rolled towels are placed inside the
germination cabinet/room for incubation.
Sand substrata: Plastic boxes are filled with sterilized sand of recommended particle size
upto 3/4th of box height. The sand is moistened upto 50% of its water holding capacity.
The seeds are planted on the leveled layer of moist sand and covered with 10-20 mm of
uncompressed sand depending on the size of the seed. Irrespective of the method, the
substratum is made wet sufficiently and uniformly before putting the seeds for germination
test and they are incubated either in a cabinet seed germinator or a walk-in germinator
room where the temperature and relative humidity are regulated as per the prescribed

specifications. For most of the agricultural and horticultural seeds the temperature range of
20° C to 35°C and the relative humidity level of 90% and above is maintained in the seed
germinator/germinator room. Light is not very much essential for seed germination except
for crops like lettuce and tobacco.
Duration of the test
The duration of sample incubation varies from crop to crop. For most of the crops first
'count is taken' on the 4th or the 5th day and the final count between 7 to 10 days. The
time for count is fixed in such a way that it is sufficient to allow seedlings to reach a stage
of development which allows for accurate evaluation. In case of sand media tests, the first
count is omitted. The test can be terminated before the end of prescribed test period, if the
sample under test meets the minimum limits of germination during the first count.
Seedling, Evaluation
During each count, the germinated seedlings and the remaining ungerminated seeds are
classified in to any of the following 5 categories.
Normal seedlings: Seedlings which shows the capacity for continued development into
mature plant when grown under favorable conditions and having well developed root and
the shoot system.
Abnormal seedlings: Seedlings with any abnormality in their root or shoot system thus
which do not have the capacity to develop into a normal plant when grow.
Hard seeds: Seeds which remain hard at the end of the prescribed test period because of
the non absorption of moisture due to the presence of impermeable seed cost. Usually hard
seeds are seen in leguminous crops.
Fresh ungerminated seeds: Seeds other than hard seeds, which remain firm, fresh and
apparently viable, even at the end of the test period.
Dead seeds: Seeds which at the end of the test period are neither hard nor fresh and
have not produced seedlings are classified as dead seeds. Dead seeds often show the
symptoms of decaying and fungal growth which can be felt by pressing the seed under
test.
Germination percentage
The replication wise details of all categories of seedlings / seeds observed during evaluation
are recorded in the seed analysis card. The result of germination test is calculated as the
average of the replicates and is expressed as percentage by number of normal seedlings.
The percentage is calculated to the nearest whole number. The percentage of abnormal
seedlings, hard, fresh ungerminated and
dead seeds is also calculated the same manner.
Retesting
When the test results are unsatisfactory due to out of tolerance performance between
replicates or : wrong evaluation of seedlings or : errors in testing conditions, a second test
is conducted by the same method or by alternative method to confirm the results before
they are declared.
Moisture determination
Seed moisture content is determined by using hot air oven or moisture meter. Seed
moisture content is expressed as percentage by weight.
Hot air oven method
Here the seed moisture is removed by drying the pre-weighted sample at a specified
temperature. The difference in weight is taken as moisture content and is expressed as a
percentage of original weight. This is the most standard and accurate method of seed
moisture determination.

Moisture meter method
Here the moisture content is determined using moisture meter which is calibrated and
standardized against air oven method. Moisture test is conducted in two replications and
the average is recorded in the seed analysis card.
Back

1/
PRESCRIBE SEED STANDARDS FOR CROPS UNDER CERTIFICATION
f
Crop
Germination Moisture Pure Seed Inert Matter O.C.S.' O.D.V.4 O.W.S.s
(minimum) (maximum) (minimum) (maximum)(maximum) (maximum) (maximum)
F C F C F C F C F C F C F C
% Number per Kg
Paddy
80 80 13.0 13.0 98.0 98.0 2.0' 2.0 10 20 10 20 10 20
Ragi
75 75 12.0 12.0 97.0 97.0 3.0 3.0 10 20
10 20
Jowar
75 75 12,0 12.0 97.0 97.0 3.0 3.0 10 20 10 20 5 10
Wheat
85 85 12.0 12.0 98.0 98.0 2.0 2.0 10 20
10 20
Maize
a. Hybrids
90 12.0 - 98.0 - 2.0 10 10 none
b. Inbredsand 80 12.0 - 98.0 - 2.0 5 5
none -
singlecrosses
c. Compositesand 90 90 12.0 12.0 98.0 98.0 2.0 2.0 10 20
none none
synthetics
Bajra
75 75 12.0 12.0 98.0 98.0 2.0 2.0 10 20
10 20
Redgram
75** 75** 9.0 9.0 98.0 98.0 2.0 2.0 5 10 10 20 5 10
Greengram and 75** 75** 9.0 9.0 98.0 98.0 2.0 2.0 5 10 10 20 5 10
blackgram
Horsegram
80 80 9.0 9.0 98.0 98.0 2.0 2.0 none 10 5 20 none none
Bengalgram
85** 85** 9.0 9.0 98.0 98.0 2.0 2.0 none 10 5 20 none none
Cowpea
75** 75** 9.0 9.0 98.0 98.0 2.0 2.0 none 10 5 20 none 10
Castor
70 70 8.0 9.0 98.0 98.0 2.0 2.0 none 10 5 10 none none
Groundnut
70 70 8.0 9.0 98.0 98.0 4.0 4.0 none - 10 none none
Sunflower
70 70 9.0 9.0 98.0 98.0 2.0 2.0 none none none none 5 10
Safflower
80 80 9.0 9.0 98.0 98.0 2.0 2.0 none none none none 5 10
Sesamum
80 80 9.0 9.0 97.0 97.0 3.0 3.0 10 20 10 20 10 20
Niger
80 80 9.0 9.0 98.0 98.0 2.0 2.0 10 20 10 20 10 20
Soyabean
70*' 70*' 12.0 12.0 98.0 98.0 2.0 2.0 none 10 5 10 5 10
Cotton
65 65 10.0 10.0 98.0 98.0 2.0 2.0 5 10
5 10
Jute
80 80 9.0 9.0 97.0 97.0 3.0 3.0 10 20 10 20 10 20
Bhendi
65*' 65** 10.0 10.0 99.0 99.0 1.0 1.0 none 5 10 20 none none
Brinjal
70 70 8.0 8.0 98.0 98.0 2.0 2.0 none none -
none none
Tomato
70 70 8.0 8.0 98.0 98.0 2.0 2.0 5 10
none none
Capsicumand 60 60 8.0 8.0 98.0 98.0 2.0 2.0 5 10 0 0 5 10
chilli
Cluster bean
70 70 9.0 9.0 98.0 98.0 2.0 2.0 10 20 10 20 none none
Peas
75 75 9.0 9.0 98.0 98.0 2.0 2.0 none 5 5 10 none none
Bottlegourd
60 60 7.0 7.0 98.0 98.0 2.0 2.0 none none -
none none
and pumpkin
Watermelonand
ridgelbitter gourd
Frenchbean
60
75
60
75
7.0
9.0
7.0
9.0
98.0
98.0
98.0
98.0
2.0
2.0
2.0
2.0
none none 5
none none 5
10
10
none none
none 10
"F' foundation, 2'C'-~ertified, 30.C.S.-other crop seeds, 40.D.V.-other distinguisha.blevarieties, 5W.S.- weed seeds,
.OW.S. - objectionable weed seeds, ** - including hard seeds.
SEED STANDARDS FOR INSECT DAMAGE
A seed lot under certification shall not have apparent or visible evidence of damage by insects for both
foundation and certified seed classes in excess of 1.0% for the seeds of maize and legumes and 0.50%
for seeds other maize and 'Iegumes unless prescribed. .
~F;

GROW-OUTTEST FOR G~!>JETIl;PURITY
The Agency conducts grow-out test to determine
genetic purity of a seed lot wherever it is a prerequisite
for grant of certificate and also on the seed lots where doubt has arisen about the genetic purity
SEED STANDARDS FOR GENETIC PURITY
otherwise
All certified seed lots shall conform to the following minimum standards for genetic purity unless
prescribed.
Class Minimum genetic;: purity (%)
Foundation
99.0
Certified
a. Varieties, composites, synthetics 98.0
b. Hybrids (except cotton and castor hybrids) 95.0
Cotton hybrids . 90.0
Castorhybrids . 85.0
*Off-type plants other than selfed plants such as segregants, out crosses and plants of other
varieties should not exceed 1.5%
REPORTING OF RESULTS
All the observations recorded in the seed analysis card are checkedfor proper entry and calculations
before reporting. The results are then decoded and transferred to the seed analysis report for further
communication to the sender of the sample. .
RECOMMENDED SEED TREATMENTS
Crop Chemical Name Quantity of chemical (g)/ Method of
100 kg seed Water (litre) treatment
I'
Paddy Thiram 75 WDP 100
(except Jyothi)
Jyothi Bavistin 100
Bajra Thiram 75 WDP or 100 0.5 Slurry treatment
Thiram 75 Dust or 300 -
Dry dressing
Captan 75 Dust 300 - Dry dressing
Brine 10% solution Solution to completely immerse seed
Sorghum Thiram 75 WDP 100 0.5 Slurry treatment
Captafol 100 0.5 Slurry treatment
Wheat Thiram 75 WDP of 100 0.5 Slurry treatment
Mancozeb or 100 0.5 Slurry treatment
Carboxin or 50 - Dry dressing
Carbendazim2 '250 -
Dry dressing
Maize Thiram 75 WDP 100 0.5 Slurry treatmnt
':1.1':

"
-
Crop Chemical Name Quantity of chemical (g)/ Method of
100 kg seed Water (litre) treatment
Bengalgram Captafol 250 - Drydressing
Blackgram Thiram 75 Dust 250 - Drydressing
Cowpea Captan 75 WDP or 100 0.5 Slurrytreatment
Thiram 75 Dust 250 - Drydressing
Greengram Thiram 75 WDP 100 0.5 Slurrytreatment
Redgram Thiram 75 WDP 100 0.5 Slurrytreatment
Sunflower ." Thiram75 Dust 250 - Drydressing
Groundnut Captan75 Dustor 250 - Drydressing
Thiram 75 WDP or 125 0.5 Slurrytreatment
.
Captafol 200 - Drydressing
Castor Organomercurial (1%) 250 -
Drydressing
Soyabean Captan75 Dustor 150 - Drydressing
Thiram 75 Dust or
Mancozeb or 300 - Drydressing
Captafol. 300 -
Drydressing
Sesamum Thiram 75 Dust 300 - Drydressing.
Cotton Captan75 Dustor 250 - Drydressing
Thiram 75 WDP 100 0.5 Slurrytreatment
Jute Captan 75 WDP 80 0.5 Slurrytreatment
Mesta Captan 75 Dust' 250 -
Drydressing
Beans Captan 75 WDP or 100 0.5 Slurrytreatment
Thiram 75 Dust 250 - Drydressing
Bhendi Thiram 75 Dust or 100 0.5 Slurrytreatment
Captan 75 Dust 250 -
Drydressing
Brinjal Thiram 75 Dust or. 250 -
Drydressing
Captan75 Dust 250 - Drydressing
Chilli Thiram75 Dust. 250 - Drydresing
Clusterbean Thiram 75 WDP ..100 0.5 Slurrytreatment
Colecrops Thiram '75Dust 250 - Diy dressing
. Cucurbits Thiram 75 Dust 250 - Drydressing
Captan75 WDP 250 -
Drydressing
Onion Thiram75 Dust 250 -
Dry dressing
Tomato Thiram 75 Dust 250 -
Dry dressing
7

Note: 1. Brine (10%) is prepared by dissolving 10g common salt (sodium ehlorh:le)in 100ml of
water. Soaking in brine has to be done only where ergot infection i5 noticed byt within the
prescribed field standard. The seed is to be dipped in brine solution for 5-1 a min and ergot
sclerotia removed. The send is washed thoroughly with water.
2. The seed is to be treated only if loose smut infection is suspected or detected in the seed.
BAGGING, TAGGING, SEALING AND GRANT OF CERTIFICATE
Every seed lot meeting the prescribed seed standard!;; for certification is duly treated with the
recommended seed-treatment chemical and is bagged in required si~es affixing ;:;eed certification tags
(blue tags for certified seed and' white tags for foundation seed) and the containtJf ig seal@d. This is
followed by issue of the Release Order (Form-II) for each seed lot.
VALIDITY PERIOD OF THE CERTIFICATE
The validity period of the seed lot will be nine months from the date of test at the time of initi(!1
certification. The validity period may be further extended for six months provided the seed conforms to
, the prescribed standards on retesting. A seed lot will be eligible for extension of the validity period as long
as it conforms to the prescribed standards. The procedure for extension of validity is as follows.
Holder of the certified seed stock or authorized representative may request the Agency for
extension of the validity of certified seed before expiry of the previous validity, Informatjc;>n regarding
name of the crop, variety, class of seed, quantity of seed in lot, lot number, size andtype of container;:;,
Release Order No. etc., should be fumished to the Agency at the time of submission of application,
The Agency will arrange for the drawing of seed sample and its analysis after verifying the tags,
labels, seals and validity period. The sample is tested for physical purity, germination and insect damage.
If reprocessing, testing and rebagging at the time of extension of validity period is requested, it may also
be considered if the Agency is of the opinion that such operation may improve the quality of seed,
After analysis of the'seed sample, if seed is found to conform to the prescribed standards, the
Agency will extend the validity of the seed for a further period of six months from the date of test. The date
of test and the validity period shall be stamped
on existing tags or new tags shall be issued. The signature
and address of the Seed Certification Officer attending to the validity work are also affixed on the tag. If
new tags are issued the information in the old tags will be transferred to the new tags allotted, A complete
record of the validation process will be maintained by the Agency.
REVOCATION OF CERTIFICATE
If the Agency is satisfied, either on reference made to it in this behalf of or otherwise that (a) the
certificate granted by it under Section-9(3) of the Seed Act has been obtained by misrepresentation as to
an essential fact or (b) the holder of the certificate has, without reasonable cause, failed to comply with
the conditions subject to which the certificate has been granted or has contravened any of the provisions
of the Act or the Rules made there-under, then, without prejudice to any other penalty to which the holder
of the certificate may be liable under the Act, the Agency may, after giving the holder of the certificate an
opportunity of showing cause, revoke the certificate under the provisions of Section -10 of the Act.
REFUSAL FOR CERTIFICATION AND APPEALS
The Agency shall have the authority. to refuse certification of any seed production field or,any
seed that does not conform to the minimum standards prescribed for the that particular crop either for
38

field or for seed or for both. Such refusal will be subject to appeal made to the Appellate authority constituted
under Section -11 (1) of the Seeds Act. 1966.
All such appeals should be made within 30 days from the date on which the decision of the
Agency is communicated, enclosing a copy of the decision of Agency against which appeal is being
preferred with the grounds for objection to such decision and a bank draft for Rs. 100.00 (Rupees one
hundred only) towards
appeal fees.
DOWNGRADING
OF SEED CLASS
If a seed field or a seed lot registered but is not found meeting prescribed standards for the class for
,
I
.
r
I
I
I
which it hasb~!3n confirms to the prescribed standards to the immediate lower class, the certification
Agency may accept such seed fields/seed lots for certification to immediate lower class provided request
has been made to this effect by the seed producer. However, downgrading of the seed class shall not be
applicable
in case of Hybrids their parents.
RECLEANING, RESAMPLING &. RETESTING
When a seed lot does not meet the prescribed seed standards certification agency on the request of seed
producer may permit Recleaning, Resampling and Retesting duly collecting the necessary charges. The
recleaning, resampling and retesting shall be permitted only once.
RETENTION OF CERTIFICATION RECORD
The certification agency shall preserve in order all the documents including the guard samples pertaining
to certification of each seed lot for two (2) years from the date of grant / extension of the certificate and
four (4) years in respect of rejected seed crops or lots from the date of communication of rejection unless
and otherwise required for longer period.
LEGAL STATUS OF CERTIFICATION
SYSTEM:
/Under Seeds Act 1966 "Seed Certificatiol')" has become a legally sanctioned system of quality control of
Seed during Production/Multiplication and distribution stages and relates to:
1
a) Section-8
b) Section-8(A)
c) Section-9
d) Section-10
e) Section-11
f) Part-IV
Refers establishment of Seed Certification Agency at state level to
discharge the function of certification.
Refers to establishment of Central Certification Board primarily to render
advisory on scientific and operational matters.
Refers to grant of Certificate by the Certificate Agency as prescribed to a
Seed lot offered for Certification.
Refers to 'evocation of Certificate issued, on breach of trust or non
accomplishment of procedure prescribed.
Refers to appeals by Growers against the decision(s) of the Seed
Certification Agency to an appelant authority.
Refers to function of Seed Certification Agency to regulate seed quality
(S€ed Rule-6) Prescribing procedure for growing, processing storage
etc. of seed crop
'On

Arranging notification of varieties,processing plants, field inspections etc. for the confirmation of field
standards.
Carrying out the education programmes to promote the use of certified Seed. Sampling Seed lots for
testing to confirm Seed Standards.
Issuance of Certificate, tag seal etc.
INTRODUCTION OF SEED ACT 1966
The Government of India enacted the sed act in 1966 and the seed rules under the act are framed in
1968. The seeds Act 1966 and the seed Rules 1968 with the amendements carried out from time to
time are in existence and inforce as on to day. -'
DECLARING THE SEED AS ESSENTIAL COMMODITY
The Government of India on 24th February, 1983 have declared the seeds of food crops, fruits and
vegetables, cotton seeds, seeds of cattle fodder and jute seeds as essential commodities under section
2 of Essential Commodity Act 1955 (10 of 1955) 'and a seeds (control) order was issued in December'
1983. This control order provide to control and regulate the production, supply and distribution of seeds
by effective check on the activities of the dealers and producers of seed.
The salient features of the Seeds Act 1966, seeds rules 1968 and the seeds (control) order 1983.
THE SEED ACT 1966
The Seeds Act 1966 is mainly applicable to the notified kind of variety in relation to any seed under
section 5. It is basically regulatory in nature and mainly to ensure that seeds of notified varieties offered
for sale conform to certain minimum limits of purity and remination,
The act provides -the onstruction of central seed committee to advice central govemment on all
matters arising out of the administration of this Act.
(section 3) to establish a central seed laboratory or declare the laboratories as central or state
(section 4)
" (section 5)
(section 6)
(section 7)
(section 8)
seed laboratorieswhere analysis of seeds of anyh notified kind or variety shall be
carried
out by seed analyst.
to notify any kind or variety to be sold for the purpose
of agriculture.
to presribe minimum limits of germination and purity standards for each category
of seeds and label the seed indicating the standards. .
Regulation of sale of seeds of notified kinds of varities,
to establish certification agency for the states.
to establish central seed certification Board and other committees,
(pection 8A to 8E)
to appoint seed Analysts, seed inspectors and specify their powers, functions and
duties.
(section 12 to 16) ti regulate, impose certain restrictions on export of seeds of notified kinds of
varieties.
(section 17) to impose certain penalities for the offences committed under Act.
" . (section 18) '- to make rules and gives proteqtion of action taken in good faith.
(section 25 and" 22)

V
THE SEED RULES 1968
The seed rules. are framed in the year 1968 giving wider scoppe of understanding various provisions of
the seeds Act 1966. The function of Cental Seed Laboratory, Sees Ceertification Agency are elaborated
dealth with. It made labelling of any notified kind of variety of seed compulsory. It provided certain
requirement to be compiled with the person carrying on the business of selling seed. These rules also
dealt the following issues.
Categorised the certified seed in to three distinct classes.
Certification procedures are dealt in detail.
Qualification of seed Analysts and his duties are specified.
'Qualification of seed inspectors and his duties are qidely defined.
Seed samplihg prodecures are dealt in detail.
Maintence of various records and issung of memorandum in form VII by seed inspector to the
dealer.' .
SEEDS (CONTROL) ORDER 1983
The seeds (control) order 1983 is promulgated under essential commodities Act of 1955 mainly with a
view to evolve a mechanism for registration of seed dealers, get regular floe of information on seed
production ;and sales and to ensure suitable
of seeds all over the country.
The order provides for drawing of samples of seeds including truthful labelled seeds and does not
envisage any requirement of sale of only notified seed. The seed control order 1983 envisages the
obligations on the part of the dealer to obtain licence (clause 3)
Display stock board and price list (clause 8).
Gice memorandum of cash or credi(ta:the purchaser (clause 9).
Maintain records and submission of reports (clause 18)
Ensure suitable distribution of seeds (clause 10)
SEED PRODUCTION
MANAGEMENT
Several factors are responsible for successful seed production of hybrids, as seed production is a highly
commercial venture, it is essential to maintain high level of crop management in order to maximise
production. -
Selection of Site and Field Preparations: The main consideration for selection of site are suitable
climatic conditions, assured rainfall or irrigation facilitity, and dry weather at harvest. The land selected for
seed production should be uniform with good drainage. The seed procluction programmes are to be
organised primarily in areas which are suitable for producing good quality seeds. The seed plot must also
have the required isolation distance to maintain purity of the seed, The seed production is to be taken up
with enterprising farming community in areas where the seed yields are high and is more economical.
The seed production is to be concentrated in few clusters of villages. Each cluster can have 2-3 continuous
villages. The number of clusters can be decided on the total seed required as per the estimation of the
demand and supply. Compact blocks are easy for supervision and maintenance of quality with I~ss isolation
problems, These clusters will minimize the nicking problems to a major extent and will also Serve as
demonstration blocks.
41

FACTORS INFLUENCING HYBRID SEED PRODUCTION
i. Planting ratio: The ideal planting ratio between male and female lines is two male rows alternated
by 4 to 6 female rows. Where the male line has smaller earheads and shorter span of flowering
compared to the female ones, it is desirable to allow only four female rows.for each pair of male
rows. The female rows can be increased to six where the male line has larger panicle and longer
span of flowering5-row thick border all round the seed production plots, must always be provided.
ii.
Plant height: Differencein heightbetween the two parents has considerable bearing on seed setting.
Where the parents are of similar height or ~here the male parent is taller than the seed parent, no
difficultyis usually experienced for good- set. But, if the pollen parent is considerably shorter than
the seed parent obtaining good seed set even when the niking is proper is rather difficult.This
problem can be avoided to some extent by planting the short parent on the raised ridges and the
taller parent in the furrows below. Urea sprays also enable to increase the height to some extent by
elongating the penduncle.
iii. Nicking: The most serious problem faced in hybrids seed production is proper nicking or
synchronizationoffloweringbetween the two parents. Allseed producers must understand thoroughly
about the floweringtime of the p~rents indifferentseasons and at differentlocations, receptivityof
stigma, pollen dispersal and its viabilityaccordingly the planting of the parents willbe undertaken in
seed production plots. Several methods are employed to overcome this problem depending upon
the situation. The commonly followedtechnique is staggered planting, Le. ,adjusting the planting
dates of the parents so that they flowersimultaneusly. Ifthe difference in 'floweringbetween the two
parents is only 2 to 4 days. It is possible to bridge the gap through selective application of foliar
sprays. (spray of urea @ 2% z to the late flowering).The application of urea sprays has to be taken
up at flowerprimordialinitiationstage (between 30-40 days after planting) and repeated 3 to 5 times
on alternative days. If the 'gap between the parents is of greater magnitude (more than 15 days)
transplanting or ratooningof the earlyparent at appropriate time could be followed.As an emergency
measure dusting or spraying of pollen collected from the male parent, ifavailable in the vicinitycan
be done.
iv.
v.
Flowering and pollen dispersal: The longer the duration of floweringin the male line is better as
pollen is available for more number of days. Since pollen is viable only for few hours after flower
opening which usually takes place in the early hourse, there is need to prolong the duration of
floweringof male line to ensure better seed set. This can be achieved by pollination,itis not safe to
rely entirely on natural wind to aid in pollen dispersal. It is desirable using artificialaids of pollen
dispersal liketapping the male plants or blowingair through empty dusters over the male heads. Itis
also advisable to spray 0.2% Borax to improve the pollen production and dispersal.
Stigma receptivity and pollen production: Generally, the stigma retains good receptivityupto 5
days after floweropening, although insome lines it is extended beyond that period. However,during
hot summer months the production is also influenced by temperatures. During winter months.
especially in areas in where the night temperatures are rather low,pollen production is appreciably
reduced. 0.2% Borax spray on both male and female lines two times from ear head emergence till
the completion of anthesis would greatly solve the problem;
4

stEPS TOIMPROVESEED QUALITY
Th important seed quality parameters are maintenance of high standards of genetic purity, germination
and physical purity,
I) Roguing: The problem of genetic purity can be solved by adopting timely roghlng In the seed plots
and mainthenal1ce of prescribed isolation distance. The removal of off-types and diseased plants
Horti tlie seeos field before they start flowering is known as rouging. This is done to avoid
contamination, out ct6Ssing and transmission of seed borne dieseases. Scientifically, roguing is the
process of negative mass selection in which 'off types' are removed and only 'true to' plants are
retained, in the whole population of seed crop. In self pollinated cops rouging should be continuously
practlMd while In cross pollinated crops. It must be completed well before the commencement of
anthesis. The anthers start shedding of pollen after anthesis and thus become the source of
contamination.
rows.
In hybrid seed production, this procedure is to be carried out both in seed and pollinator
Ii) Control of pests' and diseases: The incidence of pest and diseases 'could cause serious yield
losses both in quantity and quality if not controlled in time. Complete immunity from designated
diseases in cultivated crops is perhaps difficult. But a fair degree of resistance is always kept in view
by the breeder while evaluating crop varities for release. The environmental conditions playa key
role in the perpetuation and spred of the disease inoculum or multiplication of insects which effect
the seed crop at different growth phases. The necessitates prophylatic control measures right from
the stage of seedbed preparation to the harvesting stage. Use of prescribed fungicides!insecticides
as may be available at regular intervals not only ensures the helath of the crop but also increases
the seed yield considerably. Common practices for the control of pests and diseases are: (a) Soil
and Seed treatment, (b) Spraying! dusting on the standing crop at various stages. The concentration
of fungicides! insecticides should be adjusted in such a way that there is no scorching effect on the
crop and the objectives to arrest the spread of inoculum! insect activity is fulfilled.
iii) Harvesting and post-harvesting handling of seed crop: Supervising harvesting and after-care
during' post harvest handling of seed crops are integral part of the certification scheme. The time,
energy and money spent on growing genetically and disease-free seed crops may go waste if the
harvested seed crops are left to the vagaris of weather conditions
or if steps are not taken to complete
its processing such as threshing, winnowing, drying, cleaning, grading seed treatment, packaging,
labelling and sealing later movement of the seed lots of safe storage.
STAGES OF PRECAUTIONS
a. Harvesting and threshing: seed, on attaining physiological maturity in the field should be harvested.
b.
since it acquiries the highest degree of vigour and viability which gradually declines as it approaches
the field maturity. Moisture content is the major criteria for keeping quality.
Dryings: Seed produce, after harvesting and threshing, is subjected to sun drying to reduce the
moisture content at the production site itself before transporting it to the processing plant. Seed
produce should not be exposed to direct sunlight as it affects its quality, therefore, if necessary seed
IS dried under diffused sunflight in shade.
Grading: Grading is done by using different models of graders with prescribed aperture-size screens.
4::\

d. Seed treatment: Treatment of seed with the prescribed doses of fungicides and insecticides avoids
the diseases-causing pathogens and insects carried with seeds or their fresh entry in to it. The
cliemicals generally used for seed tretment are (a) organomercurials such as agrosan, (b) organononmetallics
such as Capton and Thlram, and (c) Inorganlc-metallics and non-mettallics like copper and
e.
f.
iv.
sulphur
compounds.
Packing: It is necessary to use the right type of unit packing material or containers to maintain the
quality to seed. The moisture content of the seed should be bought down to 6 to 8% if the seed is to
be packed in vapour-proof containers, and to 12% level for non vapour-proof containers (Jute or
cloth bag).
Labelling and sealing: Each package should be labelled in the prescribed manner and thoroughly
sealed to prevent tampering. It is necessary to mention on the lable the pedigree and the identity of
the seeds lot with respect to its status of purity, germinations, health etc. as per the requirements of
the seed legislation.
Storage: Ample precautions'should be taken to prevent the seed lots from deteribrating while in
transit and / or in storage. Emphasis should be laid on controlling stored pests and diseases and the
temperature and relative humidity status of the storage. For longer and safer storage, dry and cool
conditions are preferred, the ideal conditions can be maintained if the sum of RH.and temperature
does not exceed 100. Temperature of 60-70° F and relative humidity of 30-40% are ideally suited for
safe storage. Specific combination is to be arrived according to the ambient..