SWI 132.1.1 Seed Program
Specific Work Instruction
Official Seed Sampling

13.0 Obtaining the Submitted Sample

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The composite sample is frequently too large and must be reduced to obtain the sample for submission to the laboratory. This latter sample is known as the submitted sample.

Sample reduction by appropriate mixing and dividing methods is a requirement so that no more variation than what would be expected in simple random sampling is introduced.

If separate sub-samples from one seed lot are required for different tests (e.g., purity and/or germination, disease, or VV), these sub-samples must be taken by:

a. sampling the seed lot again, using the same approved sampling method and intensity for each sub-sample required; or

b. mixing the entire composite sample (large seeded crop kinds only) using the approved mixing and dividing method (riffle divider) to obtain each sub-sample required; or

c. submitting the entire composite sample to the seed testing laboratory as directed by the laboratory.

The samples or sub-samples should be submitted to the appropriate CFIA laboratory on a timely basis. The sampler must state on the SSF (Appendix V) if the sample has been mixed and divided. All sub-samples must be sealed as indicated in Section 15.2. Samples should not be left unprotected and should not be exposed to moisture, heat or direct sunlight.

13.1 Mixing and Dividing Method for Large-Seeded Crop Kinds

The riffle divider method is the approved mixing and dividing method for those kinds listed in Grade Tables I to III, V and VI, and XVIII. When the sampler is required to mix and divide a composite sample of these kinds, this procedure must be followed.

The divider consists of a hopper with attached channels or ducts, a frame to hold the hopper, four receiving pans and a pouring pan. Ducts or channels lead from the hopper to the collecting pans, alternate ones leading to opposite sides. The size of the channels of the riffle divider must be a minimum of two times the largest diameter of the seed being mixed and divided. This divider is suitable for most kinds of seeds, including pulse crops.

13.1.1 Riffle Divider Method for Mixing Large Seeded Crop Kinds

The composite sample must be removed from the container in which it was placed in such a manner that all seeds are retained. Therefore, if the composite sample is in:

a. a cloth bag, carefully remove the contents and turn the bag inside out and check the seams for seeds. Seed with barbs, awns, hairs etc. may adhere to the bag or become caught in the seams;

b. containers (e.g., pails), carefully remove contents and check for seeds adhering to the sides and bottom of the container.

The entire composite sample should be placed into a clean pail/seed scoop or one of the riffle divider collection containers.

Caution: Care should be taken when mixing and dividing pulses crops such as peas and soybeans as the impact of the seed in the pan may cause seed breakage.

The sampler must use the following procedures for the various phases of mixing/dividing using the riffle divider:

Mixing Operation

a. verify that the divider and four collection pans/containers are clean. Before each use, check all channels, joints and seams of the divider and collection pans to verify there are no seeds or other plant matter present;

b. place the riffle divider on a firm, level clean surface;

c. two clean empty containers are to be placed under the channels to receive the seed;

Placing the Seed into the Divider for Mixing

d. pour the whole sample into the divider by running the collection pan/ container backwards and forwards along the edge of the divider so that all the channels and spaces of the divider receive an equal amount of seed;

e. the two full containers must be replaced with two clean empty containers;

Mixing Process Now Begins

f. the contents of one full collection pan/container are to be poured into the divider by holding the long edge of the pan against the long edge of the riffle hopper and then rotating the bottom up so that the seeds pour across all channels at the same time; followed by the other full container using the same procedure. This process of mixing the entire composite sample must be repeated a minimum of three times before successive halving begins;

Dividing to Obtain the Sub-Samples for Submission to the Laboratory

g. the contents of one full collection pan/container are set aside. Empty collection pans/containers are placed under each outlet, and the contents of the other collection pan/container is poured into the hopper by holding the long edge of the pan against the long edge of the riffle hopper and then rotating the bottom up so that the seeds pour across all channels at the same time;

h. continue the successive halving process until a sub-sample of not less than the minimum weight required is obtained;

i. if the sub-samples do not meet the required size, the set aside portions can be recombined and passed through the divider as necessary to obtain the required weights of the sub-samples for submission as long as the full amount of the set-aside portion is used. It is incorrect to further subdivide a sub-sample by spooning or pouring off or weighing out a portion from the collection pan. Only a pass through the riffle divider may be used to reduce the sample size at any step;

j. continue this process until all the required sub-samples are obtained, e.g., sub-sample for the purity and/or germination and/or VV;

k. verify that the divider and containers are clean after each mixing operation. Check all channels of the divider, the joints and seams and verify that the collection pans are clean.

13.1.2 Care and Handling of the Riffle Divider

The riffle divider must be placed on a firm, level surface and be kept and stored in a clean, dry environment. The sampler must verify that the divider and the collection pans/ containers are not damaged. The divider or the collection pans must not be banged together to clean nor tools such as mallet, hammer or knife used to clean them. Whenever possible, compressed air should be used to clean the divider and collection containers. If the divider is being transported, it should be packaged in a padded box or carrying case so that it will not be damaged. If the divider or collection pans are dirty or oily, they can be washed with warm water and mild detergent. The divider should be dried thoroughly with a soft lint free cloth that will not leave any residue on the equipment and left to dry at least overnight.

13.2 Method for Small-Seeded Crop Kinds (Grade Tables IV, III-XVII and XIX-XX)

The entire composite sample must be submitted to the laboratory. To reduce the risk of cross contamination (which is greater with small-seeded species), the laboratory must conduct all mixing and dividing operations and submit any required sub-samples to the appropriate testing laboratories. The sampler must state on the SSF what tests are required.

13.3 Types of Sub-Samples

The following are the types of sub-samples routinely taken by a seed sampler. When requests to sub-sample for other purposes are received, the seed sampler must consult, as appropriate, with the Area Program Specialist and/or the CFIA seed laboratory.

13.3.1 Sub-Sample for Variety Verification (VV)

Varietal verification tests are performed to verify that the pedigreed seed has maintained its original purity and identity during multiplication, conditioning and marketing. This program for variety verification testing of pedigreed seed is necessary to fulfill Canada's obligations to the OECD Seed Schemes and is a vital check on the Canadian seed certification system.

The levels of monitoring for variety verification are:

  1. all seed lots labelled with OECD tags are to be sampled;
  2. seed lots of Foundation, Registered seed and Certified seed-only seed lots for which there are concerns regarding the purity or identity of variety should be sampled. Direction for sampling will be given through Seed Section. These samples are to be designated VV on the SSF. The sampler should indicate in the Comments section of the SSF any additional information deemed necessary;
  3. a specified percentage of seed lots from fields that were inspected by licensed crop inspectors are to be sampled. Samples may be taken by official seed samplers, if requested, or may be supplied by the authorized seed crop inspection service;
  4. Samples may be requested for specific projects identified in the I-memo from year to year. Samples submitted for these projects should be clearly identified to link to the I-Memo item or project.

The VV sample should be drawn from the seed lot or taken from the composite/submitted sample as indicated in Appendix III. When this is not possible, the sample may be taken from the retained sample as described in Section 11.5. The following identification information must be included: crop kind, variety name, grower's name, crop certificate number, lot number and seed program (e.g., licensed crop inspector, I-Memo project, OECD).

Samples to be tested under the OECD Schemes must be identified with the complete CDN lot number, including the province code. If a seed lot is re-labelled or re-fastened, the previous reference number must also be mentioned. The sampler must refer to QSP 152.1 Implementation and Administration of the OECD Seed Schemes and EU Seed Directives for further details. The SSF must fully document all the information.

Each shipment of samples must be accompanied by a list organized by the crop kind and variety, the sampler's number, OECD reference number or seed sealing number. The sampler's number and CDN lot number must also be stated on each sample. If there are ten or fewer samples in a shipment, there is no need to prepare the list, provided a copy of a SSF is enclosed for each sample.

13.3.1.1 Sample Submission Form for VV Testing

For technical reasons, samples for VV testing may not be entered into the LSTS system. Inspectors are requested to print blank SSFs from the system and complete them by hand.

13.3.1.2 Submission of Samples for VV Testing

For sample sizes, addresses and deadlines for submission, the sampler must refer to Appendix III for further details. To submit samples for VV testing, the sampler must use the following method:

  1. either, the seed lot must be sampled as described in Section 11 to obtain the VV sample or the composite sample must be sub-sampled (large seeded crop kinds only) following the approved mixing and dividing method to obtain the sub-sample as described in Section 13;
  2. the seed lot information must be fully documented on the SSF. A copy of the SSF must accompany each sample.

13.3.1.3 VV Sample Containers

The seed for VV samples should be enclosed in good quality manilla envelopes or clean unused cotton bags. Envelopes containing small grass seeds and legumes such as timothy, bluegrass, bentgrass, clovers, bird's-foot trefoil and alfalfa should be taped with masking tape (not scotch tape) or official sealing tape to avoid escaping and mixing of seeds. Samples of beans and peas should be enclosed in clean unused cotton bags. All samples must be sealed.

The sample container must be labelled with: crop kind, complete variety name, crop certificate number (if Canadian origin), or establishment lot no., grower's name or dealer where sampled, inspection sample number, date of sampling and signature of the sampler. All samples must be properly sealed (Sections 8.2 and 15.2). Samples should then be packed in strong cardboard boxes to avoid damage during transit.

Samples to be tested for VV under the OECD Seed Schemes must be identified with complete reference number, including the country code. If a seed lot is re-labelled or re-fastened, the previous reference number must also be mentioned. The sample submission form must fully document all the information. The sample must be labelled as described in Section 14.3.

13.3.2 Sampling for Moisture Test

Sampling for moisture must not be conducted when it will result in the sample being in transit over a weekend or a holiday, as the moisture test must be initiated as soon as possible after sampling. In addition, oilseeds, such as flax, rapeseed, mustard, oilseed radish or soybeans must not be sampled in a time-frame that there is any chance that the sample will arrive at the laboratory for testing on a Friday as the test requires a 17-hour drying period versus a 2-hour drying period for other crop kinds.

13.3.2.1 Sampling Requirements for Moisture Test (Oven Test)

The sample for moisture determination must be obtained immediately after sampling by:

  1. mixing the entire composite sample, by either stirring the sample in its container with a spoon or placing the opening of the original container against the opening of a similar container and pouring the seed back and forth between the two containers. This procedure must be done as quickly as possible in order to minimize the loss or gain of moisture during the mixing and sub-sampling operation. The sampler must take a minimum of three sub-samples with a spoon from different positions in the container until the minimum sample size in Appendix III has been obtained.
  2. the official seed sampler must quickly place the sub-samples into a moisture-proof container which, at minimum, is labelled with the lot number or inspection sample number. The moisture-proof container must be strong enough to prevent spillage or leakage of the seed. The sampler must verify that moisture-proof container has as much air as possible is removed and the container is closed in such a manner that no moisture can escape or air can enter.

Suitable moisture-proof containers include:

  1. non woven plastic (heavy weight plastic bags with a sealing top), re-sealable plastic bags;
    When zip-lock bags or whirl-top bags are used, they are not considered moisture-proof if just zipped or the ends of the wired ties twisted together. As much air as possible must be removed and the top of the bag must be folded over at least twice and then taped all around the top (securing the entire folded opening) with official sealing tape or masking tape (not scotch tape);
  2. polyethylene, or foil packages that can be hermetically sealed. Polyethylene, or foil packages must be hermetically sealed immediately after filling;
  3. tins or glass bottles with an airtight top. If tins or glass bottles with an airtight top are used, they must be filled to the top and the entire lid secured with official sealing tape or masking tape.

The moisture-proof container, containing the sample for moisture testing, must be placed into a clean unused cotton bag. Samples for moisture determination must be labelled as described in Section 15.3. All samples drawn for moisture determination must be sealed (Section 15.2). The moisture sample must not be enclosed inside the sample container containing the seed for the other test(s) (e.g., purity or germination), as this destroys the integrity of the sample for the latter test(s).

A SSF (Appendix V) must accompany the sample. When more than one sample (e.g., purity and/or germination) from the same seed lot is being submitted to the same laboratory, only one SSF is required. The samples can be attached and sealed together as indicated in Section 15.2.

13.3.3 Requirements for Sub-Sampling for Disease Test

Note that to avoid concerns about contamination, triers and riffle dividers need to be disinfected between each sampling and mixing operation.

The seed lot must be either:

  1. sampled by the same approved sampling method as was used to obtain the composite sample for purity and/or germination as described in Section 7; or
  2. the entire composite sample (large-seeded crop kinds only) is to be subdivided using the procedure in Section 13.

A sample of a sufficient size as described in Appendix III must be taken for submission to the laboratory.

The sub-sample for testing should be placed into a clean unused cotton bag or manilla envelope which has been labelled with the required information as described in Section 15.3. The sampler must not enclose the sample inside the sample container containing the seed for other test(s) (e.g., purity, germination, moisture) as this destroys the integrity of the sample for those tests. All samples drawn for disease testing must be sealed as indicated in Section 15.2. An SSF must accompany the sample. If more than one sample (e.g., purity and/or germination) from the same seed lot is being submitted to the same laboratory, the samples can be attached and sealed together as indicated in Section 15.2, and only one SSF is required.

13.3.4 Sampling at a Private Seed Testing Laboratory

In order to conduct monitoring of AE laboratories, a seed sampler may be required to visit a private seed testing laboratory for the purposes of obtaining a sample and the related documentation. Sampling at a private seed testing laboratory may also be required at the direction of the Seed Section or the SSTS.

The sampler must:

  1. request that the laboratory mix and divide the remaining unanalysed portion of the sample using the appropriate method described in the Canadian Methods and Procedures for Testing Seed to provide a sample of a sufficient size for the testing purpose; or
  2. obtain the entire submitted sample including the laboratory's analysed portions.

The sample taken should be placed into a clean unused cotton bag or manilla envelope which has been labelled with the required information. The sample must be sealed as described in Section 15.2. The sampler must request a copy of the laboratory's report/Certificate of Analysis and all related worksheets. A completed SSF must accompany the sample.

The sampler must provide the laboratory with a written, dated and signed notice that CFIA has removed part or all of the sample from the laboratory. The documentation is to include the laboratory's sample/test number, the crop kind, variety if applicable and any other information pertinent to the sample.

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