Seed Sampling

Seed Sampling

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All certified seed lots should meet the prescribed seed standards with respect to germination, physical purity and moisture content apart from meeting the prescribed genetic purity standards for certification (see Seed Standards). Soon after the completion of seed processing and allotment of lot number, the Seed Certification Officer with the assistance of the Senior Seed Processing Assistant / Seed Processing Assistant will draw a representative sample as per procedure in the presence of the seed producer/grower and send the sample to laboratory for analysis.

Seed sampling is aimed at obtaining a sample of the required size and consisting of the same components as the whole lot of seeds. So every effort is made to ensure that the sample drawn for analysis accurately represent the lot in question. A sample from seed lot is obtained by taking small portions (primary sample) at random throughout the lot and combining them (composite sample). The size of the composite sample should be thrice the size sufficient to provide three-sub-samples of the size required (prescribed for each crop) to be submitted for testing (see Grading of Crop Seeds). From this composite sample three sub-samples are obtained out of this, one sample is sent to the seed testing laboratory for analysis, one sub sample shall be given to the seed producer and one sample shall be retained by the seed certification officer as a guard sample. For all crop seeds where genetic purity test is a prerequisite to certification one additional sample is drawn and sent to the head office for conducting grow-out test.

Sampling intensity for drawing seed sample is as follows:-

 

Up to 5 containers; Sample form each container and always take at least 5 primary samples.
6 to 30 containers Sample is drawn from 5 containers or at least one in every 3 containers, whichever is the greater number.
31 to 400 containers Sample is drawn from 10 containers or atleast one in every 5 containers, whichever is the greater number.
401 to more containers Sample is drawn from 80 containers or atleast one in every seven containers, whichever is the greater number.

Bulk seed

 

Less than 50 Kg At least 3 primary seed samples
50 to 500 Kg At least 5 primary seed sample
501 to 3000 kg One primary samples for each 300 kg. but not less than 5 primary samples.
3001 to 20000 kg One primary samples for each 500 kg. but not less than 10 primary samples.
20,001 kg and above One primary samples for each 700 kg. but not less than 40 primary samples.

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 legumes unless prescribed.

GROW-OUT-TEST FOR GENETIC PURITY
The Agency conducts grow-out-test to determine genetic purity of a seed drawn from a 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 
All certified seed lots shall conform to the following minimum standards for genetic purity unless otherwise 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
Castor hybrids 85.0

*Off-type plants other than selfed plants such as segregants, out crosses and plants of other varieties should not exceed 1.5%

 

The Agency conducts grow-out-test to determine genetic purity of a seed drawn from a lot wherever it is a prerequisite for grant of certificate and also on the seed lots where doubt has arisen about the genetic purity. Further, in order to regulate the quality of certified seeds GOT has been made mandatory for all seed lots of Hybrids, their parents, all foundation seed lots Ragi (Finger Millet), Greengram, Blackgram, Soybean, Sunflower and all vegetable crop verities and hybrids.
Control GOT is also mandatory for the source material procured by the seed producers and certified by other State Certification Agencies and also wherever Stage-II certification is requested.
Note : However, in order to make the seeds available in time for sowing provision has been made for “Pending GOT Certification” as per the request of the seed producers. But release order (Form-II) will not be issued for such lots and also undertaking is obtained by the producers to withdraw such seed lot that have failed in GOT from the certification chain and surrender the seed certification tag for cancellation.

SEED STANDARDS FOR GENETIC PURITY
All certified seed lots shall conform to the following minimum standards for genetic purity unless
otherwise prescribed.
Class Minimum genetic purity (%)
Foundation 99.0
Certified
a. Varieties, Composites, Synthetics and Multilines 98.0
b. Hybrids 95.0
c. Certified Hybrids of Cotton, Brinjal, Tomato & Muskmelon 90.0
Castor
a. Foundation 95.0
b. Hybrids 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 and checked for proper entry and 26 calculations before reporting. The results are then decoded and transferred to the seed analysis report for further communication to the sender of the sample.
Note:
1. Brine (10%) solution is prepared by dissolving 10g common salt (sodium chloride) in 100 ml of water. Soaking in brine has to be done only where ergot infection is noticed but within the prescribed field standard. The seed is to be dipped in brine solution for 5-10 min and ergot sclerotia removed. The seed is washed thoroughly with water.
2. The seed is to be treated only if loose smut infection is suspected or detected in the seed.