Procedure of Sampling

The main objective of seed sampling is to obtain a representative sample of each lot of seed under certification.

 

DEFINITIONS

A. SEED LOT

The term seed lot is used to represent a fixed quantity of agri­cultural seeds i.e.

·         For seeds, the size of which is equal to or more than that of wheat. Permissible limit is 200 quintals.

·         For seeds, the size of which is less than that of wheat- 100 quintals.

B. PRIMARY SAMPLE

When a seed lot is sampled either from containers or in bulk several individuals samples are drawn from different containers, each such sample is called a primary sample.

C. COMPOSITE SAMPLE

All the primary samples drawn from one lot are combined to form a bulk and is called composite sample which is generally much larger than required for analysis.

D. SUBMITTED SAMPLE

A portion of seed derived from the composite sample to be submit­ted for analysis to Seed Testing Laboratory is called submitted sample.

E. WORKING SAMPLE

The sample derived in the Laboratory from the submitted sample and is used for analysis is called as working sample.

 

PROCEDURE OF SAMPLING

·         Ensure that the entire quantity of seed to be sampled be­longs to one lot.

·         Ensure that the containers are so arranged that they are conveniently accessible.

·         Check the name of kind/variety.

·         Determine the number of containers in the lot and the number of containers to be sampled for the lot.

 

INTENSITY

A. FOR PACKED SEED

1

Upto 5 containers

Sample from each container at least 5 primary samples

2

6 to 30 containers

Sample is drawn from 5 containersor at least one in every 3 containers whichever is greater

3

More than 30 containers

Sample from at least in every  5 containers or at least from 10 containers whichever is greater.

 

B. FOR BULK SEED

1

 Less than 50 kg

At least 3 primary samples

2

50 to 500 kg

At least 5 primary samples

3

Above 500 kg

upto 3000 kg

One primary sample for each 300 kg but the number should not be less than 5

4

Above 3000 kg

 One primary seed sample for each 500 kg but the number of primary seed samples should not be less than 10

·         While drawing samples as per sampling intensity, draw approximately equal amounts of primary samples.

·         For sampling seeds in containers such as coarsely woven jute bags or burlap bags and cloth bags triers can be used. For cloth bag few stitches at one of the top corners may be opened and be closed after sampling. For plastic or polyethylene bags samples by trier, probe or by hand may be taken.

·         For sampling by hand in heats as in case of cotton seeds insert hand into the seed in tight close position, open it after reaching any location inside the seed mass, collect seed and take out hand in tightly closed position.

·         For sampling by triers, insert the trier into the bag in an inverted position i.e. cavity or slot of trier facing down, reverse the trier after it has gone sufficiently into the seed mass and draw out steadily with decreasing speed.