Certifying a Wheat Seed Crop Next to a Volunteer Stand
Sunita is producing certified seed of wheat cv. HD-3086 on 2.0 ha. The field grew a different wheat variety last season, and volunteer wheat plants are present. At the tillering-stage field inspection, the inspector records 0.8% off-type plants, about 5 volunteer spikes per square metre, and 0.3% loose smut-infected ears. The nearest wheat field of another variety is 4 m away across a field bund. The crop is otherwise vigorous and free of weeds. Sunita argues that wheat is self-pollinated, so the nearby field and the volunteers cannot matter, and that she can remove the off-types after flowering. She has already harvested 1,200 kg of seed from the previous crop, which tested 88% germination, 98.0% physical purity, 0.4% other crop seed, 0.1% weed seed and 12% moisture. She wants to label this old lot as certified seed and sell it along with the new crop.
1. Evaluate the field for certification: which observations are disqualifying or manageable, and what should the inspector require before accepting it?
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The nearby field is the least serious issue because wheat is largely self-pollinated and the isolation distance for certified wheat is usually small; 4 m may be acceptable, but the current standard must be checked. The serious issues are the volunteers and the off-types. Volunteer wheat from last year's different variety is a genetic contaminant, and 5 spikes/m2 is not trivial; by flowering it will shed pollen and produce seed that cannot be separated. The 0.8% off-types are also above what a certification field inspection normally tolerates for certified seed; the exact limit depends on the class, but this level requires immediate roguing. Loose smut at 0.3% is a seed-borne disease; infected ears should be removed and destroyed before they shed spores, and the field may still be rejected if the standard is exceeded. Sunita's proposal to rogue after flowering is too late for the volunteers and smut. The inspector should require volunteer removal now, repeated roguing at tillering and before flowering, a re-inspection, and a check that the field's previous crop and variety history are documented. Acceptance should not be promised until the re-inspection shows the contaminants are below the prescribed limits.
2. Advise Sunita on the old seed lot: can it be sold as certified seed, and what tests and actions are needed?
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The old 1,200 kg lot cannot automatically be labeled certified seed just because its test numbers look close to the standards. Certification applies to a lot produced from an approved seed crop, processed and sampled under the certification protocol, and labeled with the correct class and lot number. If the lot was grown from certified seed and was already approved, its certification may still be valid only if it has been stored properly and re-tested within the prescribed period. The 88% germination is the main concern: it may meet a minimum, but it is close enough to the line that a fresh germination test is essential before sale. Physical purity 98.0%, other crop seed 0.4% and weed seed 0.1% must be compared with the current standards for the class; one failing factor fails the lot. Moisture at 12% is acceptable for wheat storage but should be confirmed. My advice: keep the old lot separate, draw a fresh representative sample, test germination, purity and moisture, verify its certification papers and source, and sell it only under the correct label-if it fails, sell as truthfully labeled non-certified grain, not as certified seed.